Added Value of Adjuvant Breathing-Based Physiotherapy in the Management of Patients with Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial

Added Value of Adjuvant Breathing-Based Physiotherapy in the Management of Patients with Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Added Value of Adjuvant Breathing-Based Physiotherapy in the Management of Patients with Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial Mohamed AbdElmoniem Mohamed, Mohamed Rafat Borham, Mohammed Ahmed Ibrahim This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8725910/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background : Chronic obstructive pulmonary disease (COPD) is a progressive disorder marked by persistent airflow limitation and systemic manifestations, including respiratory muscle dysfunction and reduced exercise tolerance. Breathing-based physiotherapy is a key component of pulmonary rehabilitation, yet its isolated effects on functional and physiological outcomes remain incompletely defined. Objective to evaluate the effectiveness of a structured breathing exercise–based physiotherapy program in patients with stable COPD, compared with standard medical therapy alone . Methods : This randomized clinical trial at Mansoura University Hospitals (October 2024–2025), 100 clinically stable COPD patients were allocated to a control group receiving optimized medical therapy or an intervention group receiving medical therapy plus structured breathing exercises. Pre- and post-intervention assessments included arterial blood gases (PaO₂, PaCO₂, SaO₂), pulmonary function tests, body mass index, and six-minute walk test (6MWT). Results: The intervention group showed significant improvements compared with controls. Mean 6MWT increased from 326 ± 80 m to 399 ± 85 m (p < 0.001), while the control group showed insignificant change (362 ± 82 m to 375 ± 79 m; p = 0.34). FEV₁ improved from 62 ± 12% to 70 ± 10% (p < 0.001) and FVC from 72 ± 14% to 79 ± 12% (p < 0.001); controls had nonsignificant changes. PaO₂ increased (70 ± 12 to 78 ± 10 mmHg; p = 0.04), SaO₂ improved (92 ± 6% to 95 ± 4%; p = 0.05), and PaCO₂ decreased (45 ± 6 to 41 ± 5 mmHg; p = 0.03) in the intervention group. Conclusion : Structured breathing exercise–based physiotherapy significantly enhances exercise capacity, pulmonary function, and gas exchange in stable COPD when added to standard medical therapy, supporting its integration into routine management. Trial registration : ClinicalTrials.gov identifier: NCT06472167 chronic obstructive pulmonary disease breathing exercises pulmonary rehabilitation physiotherapy Figures Figure 1 Figure 2 Background Chronic obstructive pulmonary disease (COPD) is a major global health problem and a leading cause of morbidity and mortality worldwide [ 1 ]. It is characterized not only by persistent airflow limitation but also by significant systemic manifestations, including respiratory muscle dysfunction, exercise intolerance, and reduced health-related quality of life [ 2 ]. Beyond pulmonary impairment, COPD is associated with systemic inflammation, oxidative stress, skeletal muscle dysfunction, and nutritional imbalance, all of which contribute to disease progression and poor clinical outcomes [ 3 ]. Respiratory muscle dysfunction, particularly diaphragmatic impairment, plays a pivotal role in ventilatory limitation and dyspnea in COPD patients [ 4 ]. Pulmonary rehabilitation is recognized as a cornerstone in the management of COPD and has been shown to improve dyspnea, exercise capacity, and quality of life [ 5 ]. Breathing exercises represent a fundamental component of pulmonary rehabilitation programs, aiming to optimize ventilatory mechanics, reduce dynamic hyperinflation, and improve respiratory efficiency [ 6 ]. Specific breathing techniques, such as diaphragmatic breathing and pursed-lip breathing, have demonstrated beneficial effects on ventilation, oxygenation, and symptom control in COPD patients [7,8]. Incentive spirometry has also been utilized to promote sustained maximal inspiration and improve lung volumes, particularly in patients with impaired ventilatory patterns [ 9 ]. Despite these potential benefits, evidence from randomized controlled trials evaluating breathing exercise–based physiotherapy as a standalone intervention compared with standard medical therapy remains limited. Identifying its impact on functional capacity and physiological parameters may help refine rehabilitation strategies and improve individualized COPD management [ 10 ]. Therefore, the present study aimed to evaluate the effectiveness of a structured breathing exercise–based physiotherapy program in COPD patients and to compare its effects on exercise tolerance, pulmonary function, and gas exchange with those receiving optimized medical treatment alone. Unlike most previous studies that evaluated comprehensive pulmonary rehabilitation programs, this randomized controlled trial specifically investigates the isolated effect of breathing exercise–based physiotherapy in chronic obstructive pulmonary disease (COPD) patients. This study uniquely compares a structured breathing exercise program added to optimized medical therapy versus medical therapy alone, allowing for clearer attribution of observed functional and physiological improvements to physiotherapy itself. Furthermore, the study incorporates a comprehensive pre- and post-intervention assessment using spirometry, lung volume measurements (residual volume and total lung capacity), arterial blood gas analysis. However, the use of exercise capacity (six-minute walk test parameters: walking distance, heart rate, and oxygen saturation) as primary outcomes provides clinically meaningful evidence to support the role of breathing-focused physiotherapy as an effective adjunctive intervention in COPD management. This multidimensional evaluation offers a more detailed understanding of the physiological and functional benefits of breathing-focused physiotherapy in COPD. Methods Study Design and Setting This randomized controlled clinical trial was conducted at the Chest Medicine Department, Mansoura University Hospitals, Egypt. A total of 100 clinically stable COPD patients were enrolled between October 2024 and October 2025 and randomly allocated into two equal groups: a control group (n = 50) receiving optimized medical therapy and intervention group (n = 50) receiving optimized medical therapy plus a structured breathing exercise program. All participants were followed up for six months, with reassessment of functional and physiological outcomes at the end of the follow-up period. The study protocol was approved by the Mansoura Faculty of Medicine Institutional Research Board (MFM-IRB: R.24.5.2638), and written informed consent was obtained from all participants prior to enrollment. Sample Size Considerations The sample size was calculated to detect clinically meaningful differences in functional capacity between the study groups following breathing exercise–based physiotherapy. Based on previous studies evaluating pulmonary rehabilitation and breathing exercises in patients with chronic obstructive pulmonary disease, an expected moderate effect size was assumed [ 11 ]. Using a two-sided significance level (α) of 0.05 and a statistical power of 80%, the minimum required sample size was estimated to be 88 patients. To enhance the statistical robustness of the study and account for potential dropouts, a total of 100 patients were enrolled and randomly allocated into two equal groups (50 patients each). Sample size calculation was performed using Power Analysis and Sample Size (PASS) software, version 8.0. Study Population Inclusion criteria Patients were included if they fulfilled the diagnostic criteria of COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD), defined as post-bronchodilator FEV₁/FVC < 0.70 with FEV₁ < 80% predicted [ 12 ]. Only clinically stable patients with no exacerbation or medication change for at least 30 days were included. All patients were ex-smokers and were receiving optimized medical therapy according to GOLD recommendations. Exclusion criteria Patients were excluded if they were current smokers, unable to perform exercise testing, or had significant comorbidities, neuromuscular disorders, or diaphragmatic paralysis, or refusal to participate. Patient Screening and Group Allocation A total of 100 COPD patients were initially screened. Following application of eligibility criteria, patients were randomly allocated into two equal groups: Group I (Control Group): receiving optimized medical therapy only and Group II (intervention Group): receiving optimized medical therapy plus a structured breathing exercise–based physiotherapy program. Both groups were reassessed after six months. Clinical and Laboratory Assessment: Clinical Assessment Collected demographic and clinical data included age, sex, smoking history (pack-years), and comorbidities such as cardiovascular disease, diabetes mellitus, and allergic rhinitis. Symptom severity was assessed using the modified Medical Research Council (mMRC) dyspnea scale. All participants underwent baseline and post-intervention evaluation including: Pulmonary Function Testing using body plethysmography Spirometry was performed in accordance with ATS/ERS standards to measure post-bronchodilator FEV₁, forced vital capacity (FVC), and FEV₁/FVC ratio. COPD severity was classified according to GOLD staging. Six-minute walk test (6MWT) performed according to American Thoracic Society guidelines [ 13 ] Laboratory Assessments Arterial blood gas analysis (PaO₂, PaCO₂, SaO₂) Intervention Educational Program Both groups completed a standardized educational program prior to the intervention, consisting of 2 weekly sessions lasting 2 hours each. The program included disease pathophysiology, medication use, self-monitoring techniques, and strategies for environmental control and symptom management [ 11 ]. Both groups received identical educational sessions to isolate the physiological effect of breathing exercise–based physiotherapy. Breathing Exercise–Based Physiotherapy In addition to the educational program, the intervention group participated in a structured breathing exercise program focusing on: Diaphragmatic Breathing – performed in supine and sitting positions to enhance abdominal expansion, slow respiratory flow, and increase expiratory efficiency. Pursed-Lip Breathing (PLB) – to prolong exhalation, improve ventilatory control, and generate a small positive end-expiratory pressure, guided initially by the therapist and gradually performed independently. Incentive Spirometry – using a flow-oriented device (e.g., Triflow) to encourage slow, deep inhalations with end-inspiratory breath hold, improving inspiratory capacity and ventilatory control. The program was delivered in progressive phases over six months, with intensity gradually increased every 8 sessions, while patients maintained their regular pharmacological regimen throughout the study [ 7 – 9 ]. Treatment Pattern Assessment Patients received optimized medical treatment according to guidelines recommendations with selection according to patient indication and presence of non-indications or contraindications[ 12 ]. COPD pharmacotherapy was documented, including long-acting β₂-agonists (LABA), long-acting muscarinic antagonists (LAMA), inhaled corticosteroids (ICS) alone or in combination with LABA, systemic corticosteroids (oral or intravenous), and combination regimens such as triple therapy (LABA/LAMA/ICS). Outcome Measures (Pre- and Post-intervention) Pulmonary function was assessed before and after the intervention using spirometry, including forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC). Lung volumes, including residual volume (RV) and total lung capacity (TLC), were measured using body plethysmography. Gas exchange was evaluated using arterial blood gas analysis. Exercise capacity was assessed using the six-minute walk test, recording walking distance, heart rate, and peripheral oxygen saturation (SpO₂). Ethical considerations The study was approved by the Institutional Research Board of the Faculty of Medicine, Mansoura University (R.24. 5.2638). Written informed consent was obtained from all participants. Statistical analysis Data were analyzed using SPSS version 22. Quantitative variables were expressed as mean ± standard deviation or median (range). Between-group comparisons were performed using Student’s t-test or Mann–Whitney test, and categorical variables were analyzed using the Chi-square test. A p-value < 0.05 was considered statistically significant. Results A total of 100 patients with COPD were included in the analysis. There were no significant differences in age, sex, BMI, smoking status, or comorbidities between groups, confirming baseline comparability. (Table 1). Table [1]: Sociodemographic characteristics of the studied patients. Variable Control group (n=50) intervention group (n=50) P value Age (years) Mean ± SD 58.3 ± 9.3 59.9 ± 8.8 0.42 BMI (kg/m²) Mean ± SD 28.3 ± 6.4 28.8 ± 6.8 0.68 Variable N (%) N (%) P value Sex Male Female 46 (92%) 4 (8%) 47 (94%) 3 (6%) 0.81 0.79 Smoking status Nonsmokers passive smokers Ex- smokers 4 (8%) 7 (14%) 39 (78%) 2 (4%) 8 (16%) 40 (80%) 0.68 0.74 0.88 Smoking severity (among ex-smokers, n=79) according to smoking index / pack-year exposure Mild Moderate Severe N=39 6 (15.3%) 24 (61.5%) 9 (23%) N=40 5 (12.5%) 25 (62.5%) 10 (25%) 0.54 0.83 0.73 Comorbidities N (%) N (%) P value Hypertension (HTN) Diabetes mellitus (DM) Ischemic heart disease (IHD) Chronic Liver disease History of DVT History of Pulmonary embolism (PE) History of ischemic Stroke Controlled Atrial fibrillation (AF) Benign prostatic hyperplasia (BPH) 30 (60%) 28 (56%) 8 (16%) 1 (2%) 1 (2%) 1 (2%) 0 (0%) 3 (6%) 0 (0%) 38 (76%) 35 (70%) 10 (20%) 5 (10%) 4 (8%) 3 (6%) 3 (6%) 0 (0%) 2 (4%) 0.13 0.21 0.79 0.20 0.35 0.61 0.24 0.24 0.47 Overall Comorbidity Burden N (%) N (%) P value COPD only COPD + Comorbidity 16 (32%) 34 (68%) 12 (24%) 38 (76%) 0.50 AF: Atrial fibrillation; BMI: body mass index; BPH: Benign prostatic hyperplasia; COPD: chronic obstructive pulmonary disease; DM: diabetes mellitus; DVT, Deep venous thrombosis; HTN: hypertension; IHD: Ischemic heart disease; PE, Pulmonary Embolism; SD: Standard Deviation. Table (2) illustrated that there were no significant differences observed in baseline respiratory symptoms, mMRC score, exacerbation rates and GOLD classifications between groups. Also, pharmacological treatment was balanced between the two groups, ensuring comparability. Table [2]: Baseline Clinical and laboratory Characteristics, and Pharmacological treatment Profile of the Studied COPD Patients Variable Control group (n=50) intervention group (n=50) P value Clinical severity Median (IQR) Median (IQR) P value mMRc dyspnea scale 3 (2-4) 3 (2-4) 0.88 GOLD classification N (%) N (%) P value GOLD B GOLD E 27 (54.0%) 23 (46.0%) 26 (52.0%) 24 (48.0%) 0.91 0.88 Exacerbations (per year), mean ± SD 2.6 ± 0.9 2.7 ± 0.9 0.58 Symptoms N (%) N (%) P value Dyspnea Cough Expectoration wheezes 50 (100%) 40(80%) 13(26%) 22(44%) 49 (98%) 36(72%) 12(24%) 19(38%) 0.82 0.34 0.88 0.53 Medication N (%) N (%) P value single therapy SABA LABA LAMA ICS Systemic steroid 23 (46%) 44 (88%) 18 (36%) 15 (30%) 14 (28%) 26 (52%) 48 (96%) 22 (44%) 18 (36%) 12 (24%) 0.21 0.18 0.40 0.51 0.65 Combined therapy LABA+LAMA LABA+ICS LABA+LAMA+ICS 8 (16%) 5 (10%) 10 (20%) 10 (20%) 6 (12%) 12 (24%) 0.61 0.75 0.63 CBC Median (IQR) Median (IQR) P value Eosinophils (%) NLR PLR 0.63 (0.04–1.4) 4.3 (1.5–6.1) 0.54 (0.09–0.77) 0.59 (0.02–1.5) 4.3 (1.3–7.2) 0.66 (0.05–1.38) 0.81 0.88 0.72 Mean ± SD Mean ± SD P value Neutrophils (%) Lymphocytes (%) Hemoglobin (g/dL) Platelets (×10³/µL) 70.6 ± 13.3 21.5 ± 9.0 12.8 ± 1.8 251 ± 96 68.9 ± 15.1 21.6 ± 10.2 12.7 ± 1.6 249 ± 92 0.55 0.97 0.77 0.89 Data are presented as mean ± standard deviation (SD), median (interquartile range, IQR), or number (percentage), as appropriate. mMRC, modified Medical Research Council; GOLD, Global Initiative for Chronic Obstructive Lung Disease; LABA, long-acting β₂-agonist; LAMA, long-acting muscarinic antagonist; ICS, inhaled corticosteroids; SABA, short-acting β₂-agonist.; SD: Standard Deviation. NLR: Neutrophil/ lymphocyte ratio; PLR: Platelet/Lymphocyte Ratio Table (3) demonstrated that breathing exercise–based physiotherapy led to significant improvements in pH, pO₂, and SaO₂ and reduction of pCO₂ compared with controls, reflecting enhanced gas exchange. Table [3]: ABG parameters (Baseline ± Follow-up) in COPD Patients ABG Parameter Control group (Baseline) Control group (Follow-up) P value intervention group (Baseline) intervention group (Follow-up) P value p-value (group comparison) PH pCO₂ (mmHg) HCO₃⁻ (mmol/L) pO₂ (mmHg) SaO₂ (%) 7.37 ± 0.04 46 ± 7 27 ± 4 68 ± 13 91 ± 5 7.38 ± 0.04 44 ± 6 27 ± 3 73 ± 12 93 ± 4 0.42 0.56 0.44 0.38 0.38 7.37 ± 0.04 45 ± 6 28 ± 4 70 ± 12 92 ± 6 7.41 ± 0.03 41 ± 5 26 ± 3 78 ± 10 95 ± 4 0.02 0.03 0.05 0.04 0.05 0.04 0.05 0.12 0.03 0.04 ABG: arterial blood gas; pCO₂: partial pressure of carbon dioxide; pO₂: partial pressure of oxygen; SaO₂: arterial oxygen saturation. Table (4) disclosed that there was Significant improvements in FEV₁ and FVC were observed in the intervention group compared to controls, supporting functional benefit. Furthermore, Physiotherapy reduced air trapping (RV, RV/TLC) and slightly increased TLC, indicating improved lung mechanics. Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive value of baseline spirometric parameters. ROC curve analysis demonstrated that baseline FEV₁ (%) was a significant predictor of response to breathing exercises in COPD patients (AUC = 0.76 (95% CI: 0.65–0.87), p < 0.001). A cutoff value of approximately 55% predicted provided the best balance between sensitivity and specificity (figure 1). Table [4]: Spirometer and Lung volumes parameters (Baseline ± Follow-up) in COPD Patients Spirometer Parameter Control group (Baseline) Control group (Follow-up) P value intervention group (Baseline) intervention group (Follow-up) P value p-value (group comparison) FEV1/FVC FEV1 (%) FVC (%) MMEF25-75 (%) 55 ± 10 61 ± 13 71 ± 15 48 ± 12 56 ± 9 63 ± 12 73 ± 13 49 ± 11 0.87 0.31 0.40 0.76 54±9 62 ± 12 72 ± 14 47 ± 13 58 ± 8 70 ± 10 79 ± 12 60 ± 12 0.04 0.001 0.001 <0.001 0.02 <0.001 <0.001 <0.001 Lung volumes RV (%) TLC (%) RV\TLC 95 ± 13 102 ± 14 0.51±0.11 92 ± 12 103 ± 13 0.49 ± 0.10 0.56 0.62 0.58 92 ± 12 101 ± 15 0.52 ± 0.12 78 ± 10 104 ± 13 0.42 ± 0.10 0.001 0.04 0.002 <0.001 0.08 <0.001 A p value < 0.05 was considered statistically significant. FEV₁, forced expiratory volume in one second; FVC, forced vital capacity; MMEF, maximal mid-expiratory flow; RV, residual volume; TLC, total lung capacity. Based on a predefined clinically meaningful threshold, patients were classified into responders and non-responders according to post-physiotherapy improvement in FEV₁. Thirty-seven patients (74%) were classified as responders, achieving an increase in FEV₁ ≥12% following breathing exercise–based physiotherapy [6, 11], whereas 13 patients (26%) were classified as non-responders. Responders demonstrated a significantly greater improvement in FEV₁, supporting its role as a key functional marker of treatment response. Although reductions in RV/TLC were observed in both groups, a greater magnitude of improvement was observed in the overall intervention group compared with controls, without reaching statistical significance, suggesting comparable improvements in air trapping. Similarly, both responders and non-responders showed clinically meaningful increases in six-minute walk distance, without significant differences between groups. These findings support the presence of distinct responder and non-responder phenotypes, with FEV₁ emerging as the most sensitive parameter for discriminating treatment response (Table 5). Table [5]: Responder and non-responder analysis in the intervention group Variable Responder (n=37) Non-responder (n=13) P value No. of patients (%) 37 patients (74%) 13 patients (26%) - Baseline FEV1 (%) 53.7 ± 20.3 48.7 ± 15.5 0.37 Follow-up FEV₁ (%) 63.9 ± 24.1 54.0 ± 17.1 0.12 ΔFEV₁ (%) 18.9 ± 3.6 10.9 ± 0.6 <0.001 Baseline 6MWT (m) 355.5± 87.9 344.0± 77.2 0.66 Follow-up 6MWT (m) 404.2± 49.0 409.2± 41.2 0.72 Δ6MWT (m) 48.8±92.9 65.2±84.0 0.56 Baseline RV/TLC 0.49± 0.23 0.45± 0.19 0.54 Follow-up RV/TLC 0.41± 0.08 0.44± 0.09 0.14 ΔRV/TLC −0.11±0.07 −0.08±0.06 0.52 Data are presented as mean ± standard deviation (SD); Responders were defined as patients achieving an increase in FEV₁ ≥12% from baseline following breathing exercise–based physiotherapy; Δ indicates change from baseline to follow-up; FEV₁, forced expiratory volume in one second; FVC, forced vital capacity; 6MWT = six-minute walk test;; RV, residual volume; TLC, total lung capacity. Table (6) shows that 6MWT distance and SpO₂ improved significantly in the intervention group, confirming enhanced exercise capacity. Table [6]: 6MWT parameters (Baseline ± Follow-up) in COPD Patients Parameter Control group (Baseline) Control group (Follow-up) P value intervention group (Baseline) intervention group (Follow-up) P value p-value (group comparison) Distance (m) SaO₂ mean (%) HR mean (bpm) 362 ± 82 95 ± 3 105 ± 14 375 ± 79 95 ± 2 104 ± 13 0.34 0.77 0.52 326 ± 80 94 ± 3 104 ± 15 399 ± 85 96 ± 2 99 ± 12 0.001 0.001 0.002 <0.001 0.002 0.04 *p < 0.05 was considered statistically significant 6MWT = six-minute walk test; SaO₂: arterial oxygen saturation; HR= Heart rate. Table (7) displayed that Physiotherapy strengthened correlations between lung function, gas exchange, and exercise capacity, demonstrating a physiological link between improvements in mechanics and functional performance. Table [7]: Correlation between pulmonary function and 6MWT in intervention group (Baseline versus Follow-up) Variable 1 Variable 2 r (Baseline) p value r (Follow-up) p value FEV₁ 6MWT Distance 0.48 0.01 0.65 <0.001 FVC 6MWT Distance 0.42 0.02 0.60 0.001 FEV₁/FVC 6MWT Distance 0.31 0.05 0.42 0.01 RV/TLC 6MWT Distance -0.40 0.008 -0.52 0.002 SaO₂ 6MWT Distance 0.35 0.03 0.48 0.004 pCO₂ FEV₁ -0.28 0.06 -0.39 0.02 RV FEV₁ -0.43 0.005 -0.55 0.001 TLC 6MWT Distance 0.30 0.05 0.41 0.01 HR Mean 6MWT Distance -0.25 0.08 -0.35 0.03 FEV1: Forced expiratory volume at 1st second; 6MWT = six-minute walk test; SaO₂: arterial oxygen saturation; HR= Heart rate; pCO₂: partial pressure of carbon dioxide; RV, residual volume; TLC, total lung capacity. *p < 0.05 was considered statistically significant Discussion This randomized controlled trial investigated the isolated effect of a structured breathing exercise–based physiotherapy program in patients with stable chronic obstructive pulmonary disease. The main findings demonstrate that adding breathing-focused physiotherapy to optimized medical treatment leads to significant improvements in gas exchange, pulmonary function, lung volumes, and exercise capacity compared with optimized medical therapy alone. Importantly, this study provides evidence that breathing exercises, even when applied without comprehensive pulmonary rehabilitation programs, can induce clinically and physiologically meaningful benefits in COPD patients. COPD is increasingly understood as a multisystem disease characterized by airflow limitation, respiratory muscle dysfunction, impaired gas exchange, and reduced exercise tolerance, all of which contribute to disability and poor prognosis [ 1 – 4 ]. While pharmacological therapy remains the cornerstone of symptom control and exacerbation prevention, its effect on ventilatory mechanics and functional capacity is limited, particularly in patients with advanced disease [ 12 ]. Consequently, non-pharmacological interventions such as pulmonary rehabilitation have gained a central role in comprehensive COPD management [ 5 , 6 ]. Most previous studies evaluating pulmonary rehabilitation have focused on multidisciplinary programs incorporating aerobic exercise training, resistance training, education, and breathing techniques [ 5 , 6 , 10 ]. These studies consistently demonstrated improvements in dyspnea, exercise tolerance, and quality of life; however, the contribution of individual components—particularly breathing exercises—has remained unclear. The present study addresses this gap by isolating breathing exercise–based physiotherapy as the primary intervention, allowing a more precise evaluation of its physiological and functional effects. The significant improvement in arterial blood gas parameters observed in the intervention group reflects enhanced ventilatory efficiency and alveolar ventilation. These findings are in agreement with earlier studies by Thomas et al. [ 7 ], who reported that breathing retraining techniques improve ventilatory control and reduce dyspnea in patients with obstructive airway diseases. Similarly, pursed-lip breathing has been shown to prolong expiration, reduce expiratory flow limitation, and alleviate dynamic hyperinflation, resulting in improved oxygenation and reduced carbon dioxide retention [8]. The present study extends these observations by demonstrating that such physiological benefits translate into measurable improvements in arterial blood gases within a randomized controlled design. Regarding pulmonary function, the observed improvements in FEV₁ and FVC in the intervention group contrast with the minimal or absent changes typically reported with pharmacological therapy alone [ 12 ]. Previous rehabilitation studies have reported modest spirometric improvements, often attributed to reduced hyperinflation rather than true reversal of airflow obstruction, [ 6 , 10 ]. The significant improvement in MMEF25–75% suggests enhanced small airway function, which may partially explain the observed reduction in air trapping and improvement in exercise capacity. In line with this concept, the current study demonstrated significant reductions in residual volume and RV/TLC ratio, suggesting decreased air trapping and improved lung mechanics. These findings support the hypothesis that breathing exercises enhance expiratory efficiency and diaphragmatic function, thereby improving lung volume distribution rather than directly altering airway caliber. The role of diaphragmatic dysfunction in COPD has been well documented using imaging and physiological studies [ 4 ]. Smargiassi et al. [ 4 ] demonstrated impaired diaphragmatic mobility and thickness in COPD patients, which correlated with disease severity and dyspnea. While that study focused on diagnostic assessment, the present trial provides interventional evidence that targeted breathing exercises can partially reverse the functional consequences of diaphragmatic impairment, as reflected by improved lung volumes and ventilatory indices. Exercise intolerance is a hallmark of COPD and a strong predictor of morbidity and mortality [ 1 , 11 ]. In the current study, the intervention group showed a significant increase in six-minute walk distance, accompanied by improved oxygen saturation and a more favorable heart rate response. These improvements exceeded the minimal important difference for the six-minute walk test reported by Holland et al. [ 11 ], underscoring their clinical significance. Previous pulmonary rehabilitation studies have attributed improvements in exercise capacity primarily to peripheral muscle conditioning and cardiovascular adaptations [ 5 , 10 ]. However, the present findings suggest that improving ventilatory efficiency alone—through breathing-focused physiotherapy—can substantially enhance exercise performance. This observation is particularly relevant for patients who are unable to participate in high-intensity exercise training due to comorbidities or severe dyspnea. A distinctive strength of this study lies in the correlation analysis between pulmonary function, gas exchange, and exercise capacity. At baseline, correlations between spirometric parameters, lung volumes, arterial blood gases, and six-minute walk distance were modest, reflecting the complex and multifactorial nature of exercise limitation in COPD. Following physiotherapy, these correlations became stronger and more consistent, particularly between FEV₁, RV/TLC, SaO₂, and walking distance. This finding suggests that breathing exercise–based physiotherapy improves not only individual physiological parameters but also the functional integration between respiratory mechanics and exercise performance. Few previous studies have explored how rehabilitation modifies the relationships between physiological variables [ 10 ]. The strengthening of correlations between pulmonary function parameters (particularly FEV₁ and RV/TLC) and six-minute walk distance after intervention further supports that responders achieved physiologically meaningful improvements that translated into functional capacity. Importantly, responder status was not associated with baseline demographic characteristics, body mass index, comorbidity burden, baseline symptoms, or pharmacological treatment, suggesting that response to breathing exercise–based physiotherapy is driven primarily by physiological reserve rather than clinical profile. ROC curve analysis revealed that baseline FEV₁ (%) has good discriminatory ability for predicting response to breathing exercises. This finding suggests that baseline spirometric assessment may serve as a simple, clinically applicable tool to identify patients most likely to benefit from breathing-focused physiotherapy, allowing more individualized and efficient implementation of non-pharmacological interventions. The concept of heterogeneous responses to rehabilitation is consistent with previous pulmonary rehabilitation literature describing responder and non-responder phenotypes among COPD patients [ 14 , 15 ]. The responder analysis further emphasizes the heterogeneous nature of response to breathing exercise–based physiotherapy in COPD. Despite comparable improvements in exercise capacity, only a subset of patients achieved a clinically meaningful improvement in airflow limitation and lung hyperinflation. This finding is consistent with previous pulmonary rehabilitation literature describing responder and non-responder phenotypes and inter-individual variability in treatment response [ 6 , 14 , 15 ]. Although baseline characteristics were comparable between responders and non-responders, responders demonstrated a significantly greater improvement in FEV₁, supporting its role as a key functional marker of response to breathing exercise–based physiotherapy. Importantly, correlation analysis showed that post-intervention pulmonary function parameters, particularly FEV₁ and RV/TLC, were more strongly associated with six-minute walk distance compared with baseline. This finding suggests that responders achieved physiologically meaningful improvements in ventilatory mechanics and reduced air trapping that translated into functional exercise capacity. However, non-responders, despite showing clinically relevant improvements in six-minute walk distance, did not exhibit comparable physiological changes, indicating that functional gains alone may not fully reflect underlying ventilatory improvement. Together, these findings support the presence of distinct responder and non-responder phenotypes and highlight FEV₁ as the most sensitive parameter for discriminating meaningful treatment response. In contrast, the control group receiving optimized medical therapy alone showed no significant improvements in pulmonary function, gas exchange, or exercise capacity. This finding aligns with GOLD recommendations, which acknowledge that bronchodilators and inhaled corticosteroids primarily improve symptoms and exacerbation rates but have limited effects on exercise tolerance and lung mechanics in stable COPD [ 12 ]. The lack of significant physiological change in the control group further emphasizes the added value of breathing exercise–based physiotherapy beyond standard pharmacological management. Hence, these results have important clinical implications. Breathing exercise–based physiotherapy represents a low-cost, safe, and easily implementable intervention that can be incorporated into routine COPD care, even in resource-limited settings. Unlike comprehensive pulmonary rehabilitation programs, which require specialized equipment and multidisciplinary teams, breathing-focused physiotherapy can be delivered in outpatient clinics or at home with minimal supervision. This makes it particularly attractive for healthcare systems with limited access to full rehabilitation services. Moreover, the ability to identify responders using baseline FEV₁ may further enhance the cost-effectiveness and clinical impact of this intervention by targeting patients most likely to benefit. This multidimensional analysis strengthens causal inference by linking physiological improvement to functional outcomes. However, Future studies with larger cohorts and multivariable analyses are warranted to identify demographic and clinical predictors of response and to support personalized physiotherapy strategies in COPD patients. Conclusion Addition of a structured breathing exercise–based physiotherapy program to optimized medical therapy results in significant improvements in gas exchange, pulmonary function, and exercise capacity in patients with stable chronic obstructive pulmonary disease. These findings support the role of breathing-focused physiotherapy as an effective and clinically relevant adjunctive intervention, contributing to improved physiological efficiency and functional performance beyond pharmacological treatment alone Limitations This study has limitations. First, the study was conducted at a single center, which may limit the generalizability of the findings to broader COPD populations. Second, the follow-up period was relatively short, and long-term sustainability of the observed improvements could not be assessed. Third, although the study focused on isolating the effect of breathing exercise–based physiotherapy, quality-of-life measures and patient-reported outcomes were not included, which could have provided additional insight into the clinical impact of the intervention. Finally, the absence of direct measurements of diaphragmatic function or dynamic hyperinflation during exercise limits mechanistic interpretation of the observed improvements. Recommendations Structured breathing exercise–based physiotherapy should be considered an effective adjunct to optimized medical therapy in stable COPD patients, particularly for improving gas exchange and exercise tolerance. Future studies should include multicenter designs with larger sample sizes and longer follow-up periods to assess the durability of benefits. Incorporation of patient-reported outcomes, diaphragmatic imaging, and dynamic assessments during exercise may further elucidate the mechanisms underlying physiotherapy-induced improvements. Additionally, comparative studies evaluating breathing-focused physiotherapy against comprehensive pulmonary rehabilitation programs may help optimize individualized rehabilitation strategies in COPD management Abbreviations • ABG Arterial Blood Gases • AF Atrial Fibrillation • BMI Body Mass Index • BPH Benign Prostatic Hyperplasia • COPD Chronic Obstructive Pulmonary Disease • DM Diabetes Mellitus • DVT Deep Venous Thrombosis • FEV₁ Forced Expiratory Volume in the First Second • FVC Forced Vital Capacity • GOLD Global Initiative for Chronic Obstructive Lung Disease • HTN Hypertension • ICS Inhaled Corticosteroids • IHD Ischemic Heart Disease • LABA Long-Acting β₂-Agonist • LAMA Long-Acting Muscarinic Antagonist • mMRC Modified Medical Research Council Dyspnea Scale • pCO₂ Partial Pressure of Carbon Dioxide • PE Pulmonary Embolism • pO₂ Partial Pressure of Oxygen • RV Residual Volume • SaO₂ Arterial Oxygen Saturation • SD Standard Deviation • TLC Total Lung Capacity Declarations The authors have no relevant financial or non-financial interests to disclose. Ethics approval and consent to participate This study was approved by the research ethics committee of the chest medicine department of the Faculty of Medicine at Mansoura University. Reference number of approval: R.24. 5.2638. Consent for publication : All patients included in this study gave written informed consent to publish the data contained in this study. Competing interests : The authors declare that they have no competing interests. Funding: Not applicable (no funding was received for this study). Author Contribution MAM and MAI conceived and designed the study. MAM and MRB performed patient enrollment and data collection. MAM analyzed the data and drafted the manuscript. MAM, MAI, and MRB critically reviewed and revised the manuscript for important intellectual content. All authors read and approved the final version of the manuscript. Acknowledgement: Not applicable Data Availability Available on request with the corresponding author. References López-Campos, J. L., Tan, W., & Soriano, J. B. (2016). Global burden of COPD. Respirology, 21 (1), 14–23. https://doi.org/10.1111/resp.12660 Brassington, K., Selemidis, S., Bozinovski, S., & Vlahos, R. (2019). Comorbid cardiovascular disease in chronic obstructive pulmonary disease. Clinical Science, 133 (8), 885–904. https://doi.org/10.1042/CS20180764 Fischer, B. M., Pavlisko, E., & Voynow, J. A. (2011). Pathogenic triad in COPD: Oxidative stress, protease–antiprotease imbalance, and inflammation. International Journal of Chronic Obstructive Pulmonary Disease, 6 , 413–421. https://doi.org/10.2147/COPD.S10770 Smargiassi, A., Inchingolo, R., Tagliaboschi, L., Di Marco, F., Valente, S., & Corbo, G. M. (2014). Ultrasonographic assessment of the diaphragm in chronic obstructive pulmonary disease. Respiration, 87 (5), 364–371. https://doi.org/10.1159/000358672 Spruit, M. A., & Singh, S. J. (2013). Pulmonary rehabilitation: Key concepts. Chest, 144 (3), 1091–1093. https://doi.org/10.1378/chest.13-1028 Rochester, C. L., Vogiatzis, I., Holland, A. E., et al. (2015). An official American Thoracic Society/European Respiratory Society policy statement: Pulmonary rehabilitation. American Journal of Respiratory and Critical Care Medicine, 192 (11), 1373–1386. https://doi.org/10.1164/rccm.201510-1966ST Thomas, M., McKinley, R. K., Freeman, E., & Foy, C. (2003). Breathing retraining for dysfunctional breathing in asthma and chronic obstructive pulmonary disease: A randomized controlled trial. Thorax, 58 (2), 110–115. https://doi.org/10.1136/thorax.58.2.110 Nguyen, J., & Duong, H. (2020). Pursed-lip breathing . In StatPearls. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK545289/ Watchie, J. (2010). Cardiovascular and pulmonary physical therapy: Evidence and practice (2nd ed.). Saunders Elsevier. Nishiyama, O., Taniguchi, H., Kondoh, Y., et al. (2005). Factors that maintain the long-term benefits of pulmonary rehabilitation in patients with COPD. Quality of Life Research, 14 (10), 2315–2321. https://doi.org/10.1007/s11136-005-8418-4 Holland, A. E., Hill, C. J., Rasekaba, T., Lee, A., Naughton, M. T., & McDonald, C. F. (2010). Updating the minimal important difference for six-minute walk distance in patients with chronic obstructive pulmonary disease. Archives of Physical Medicine and Rehabilitation, 91 (2), 221–225. https://doi.org/10.1016/j.apmr.2009.10.017 Global Initiative for Chronic Obstructive Lung Disease. (2024). Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease . GOLD. https://goldcopd.org ATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. (2002). ATS statement: Guidelines for the six-minute walk test. American Journal of Respiratory and Critical Care Medicine, 166 (1), 111–117. https://doi.org/10.1164/ajrccm.166.1.at1102 Spruit, M. A., Singh, S. J., Garvey, C., et al. (2013). An official American Thoracic Society/European Respiratory Society statement: Key concepts and advances in pulmonary rehabilitation. American Journal of Respiratory and Critical Care Medicine, 188 (8), e13–e64. https://doi.org/10.1164/rccm.201309-1634ST Jones, S. E., Green, S. A., Clark, A. L., et al. (2014). Pulmonary rehabilitation following acute exacerbation of COPD: A randomized controlled trial. Thorax, 69 (2), 181–186. https://doi.org/10.1136/thoraxjnl-2013-203808 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8725910","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":588367456,"identity":"343a1d80-01a0-428c-992e-0450db0d3840","order_by":0,"name":"Mohamed AbdElmoniem Mohamed","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA60lEQVRIiWNgGAWjYDCCA0CcUGFjxw/lMzYQpeXBmbRkyQZStDA+bDvMuOEAsVr4bh9g3ZDYdpjZ+NrhZw9/MNjIbjjAfPgFPi2S5xLYbiScS+czu51mbszDkGa84QBbmgU+LQZnGIBayqyZzW4nmEkzMBxO3HCAx8yAsBY2ZsbNs9O/Sf5g+A/Uwv+NCC1tzowbpHPMJHgYDoBsYX6A1y9nGNtuJAADWeJ2Tpk0j0Gy8czDbGb4dDDwnWE+dvMHKCpnp2+T/FFhJ9t3vPnxB7x6UCMC5AlmBjYJ/FqwAGYCtoyCUTAKRsEIAwDHtlAivAc7mQAAAABJRU5ErkJggg==","orcid":"","institution":"Mansoura University","correspondingAuthor":true,"prefix":"","firstName":"Mohamed","middleName":"AbdElmoniem","lastName":"Mohamed","suffix":""},{"id":588367458,"identity":"bb698805-f7d7-4d29-a4b7-2e45b27094f5","order_by":1,"name":"Mohamed Rafat Borham","email":"","orcid":"","institution":"Mansoura University","correspondingAuthor":false,"prefix":"","firstName":"Mohamed","middleName":"Rafat","lastName":"Borham","suffix":""},{"id":588367463,"identity":"38b79739-be7f-46ed-9b2e-5be923194ca5","order_by":2,"name":"Mohammed Ahmed Ibrahim","email":"","orcid":"","institution":"Mansoura University","correspondingAuthor":false,"prefix":"","firstName":"Mohammed","middleName":"Ahmed","lastName":"Ibrahim","suffix":""}],"badges":[],"createdAt":"2026-01-29 01:38:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8725910/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8725910/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":102442244,"identity":"6acdc564-6e8d-4123-b077-a4b7ae4856bf","added_by":"auto","created_at":"2026-02-11 17:03:46","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":115263,"visible":true,"origin":"","legend":"\u003cp\u003eROC curve of baseline FEV₁ (%) for predicting response to breathing exercises in patients with chronic obstructive pulmonary disease. Response was defined as a ≥12% improvement in FEV₁ following intervention.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eThe area under the curve (AUC) indicates good discriminatory ability of baseline FEV₁\u003c/em\u003e\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8725910/v1/b8d713e7ec5b2354df5af7cc.png"},{"id":102442245,"identity":"71e79d36-3a8d-4ebf-bc27-8996b3dff34c","added_by":"auto","created_at":"2026-02-11 17:03:46","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":64045,"visible":true,"origin":"","legend":"\u003cp\u003eSix-minute walk test parameters in physiotherapy and control groups at baseline and six-month follow-up. (A) 6MWT distance, (B) mean arterial oxygen saturation (SaO₂), and (C) mean heart rate.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8725910/v1/dd7893ccf91ee812a25ef9cd.png"},{"id":105977948,"identity":"1efda3c0-449b-4962-855a-d68717fa4088","added_by":"auto","created_at":"2026-04-02 05:56:49","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1806464,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8725910/v1/f122e21e-3221-4604-bc7e-0d440b3c44a0.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Added Value of Adjuvant Breathing-Based Physiotherapy in the Management of Patients with Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial","fulltext":[{"header":"Background","content":"\u003cp\u003eChronic obstructive pulmonary disease (COPD) is a major global health problem and a leading cause of morbidity and mortality worldwide [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. It is characterized not only by persistent airflow limitation but also by significant systemic manifestations, including respiratory muscle dysfunction, exercise intolerance, and reduced health-related quality of life [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBeyond pulmonary impairment, COPD is associated with systemic inflammation, oxidative stress, skeletal muscle dysfunction, and nutritional imbalance, all of which contribute to disease progression and poor clinical outcomes [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Respiratory muscle dysfunction, particularly diaphragmatic impairment, plays a pivotal role in ventilatory limitation and dyspnea in COPD patients [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePulmonary rehabilitation is recognized as a cornerstone in the management of COPD and has been shown to improve dyspnea, exercise capacity, and quality of life [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Breathing exercises represent a fundamental component of pulmonary rehabilitation programs, aiming to optimize ventilatory mechanics, reduce dynamic hyperinflation, and improve respiratory efficiency [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSpecific breathing techniques, such as diaphragmatic breathing and pursed-lip breathing, have demonstrated beneficial effects on ventilation, oxygenation, and symptom control in COPD patients [7,8]. Incentive spirometry has also been utilized to promote sustained maximal inspiration and improve lung volumes, particularly in patients with impaired ventilatory patterns [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite these potential benefits, evidence from randomized controlled trials evaluating breathing exercise\u0026ndash;based physiotherapy as a standalone intervention compared with standard medical therapy remains limited. Identifying its impact on functional capacity and physiological parameters may help refine rehabilitation strategies and improve individualized COPD management [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTherefore, the present study aimed to evaluate the effectiveness of a structured breathing exercise\u0026ndash;based physiotherapy program in COPD patients and to compare its effects on exercise tolerance, pulmonary function, and gas exchange with those receiving optimized medical treatment alone.\u003c/p\u003e \u003cp\u003eUnlike most previous studies that evaluated comprehensive pulmonary rehabilitation programs, this randomized controlled trial specifically investigates the isolated effect of breathing exercise\u0026ndash;based physiotherapy in chronic obstructive pulmonary disease (COPD) patients. This study uniquely compares a structured breathing exercise program added to optimized medical therapy versus medical therapy alone, allowing for clearer attribution of observed functional and physiological improvements to physiotherapy itself.\u003c/p\u003e \u003cp\u003eFurthermore, the study incorporates a comprehensive pre- and post-intervention assessment using spirometry, lung volume measurements (residual volume and total lung capacity), arterial blood gas analysis. However, the use of exercise capacity (six-minute walk test parameters: walking distance, heart rate, and oxygen saturation) as primary outcomes provides clinically meaningful evidence to support the role of breathing-focused physiotherapy as an effective adjunctive intervention in COPD management. This multidimensional evaluation offers a more detailed understanding of the physiological and functional benefits of breathing-focused physiotherapy in COPD.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design and Setting\u003c/h2\u003e \u003cp\u003eThis randomized controlled clinical trial was conducted at the Chest Medicine Department, Mansoura University Hospitals, Egypt. A total of 100 clinically stable COPD patients were enrolled between October 2024 and October 2025 and randomly allocated into two equal groups: a control group (n\u0026thinsp;=\u0026thinsp;50) receiving optimized medical therapy and intervention group (n\u0026thinsp;=\u0026thinsp;50) receiving optimized medical therapy plus a structured breathing exercise program. All participants were followed up for six months, with reassessment of functional and physiological outcomes at the end of the follow-up period. The study protocol was approved by the Mansoura Faculty of Medicine Institutional Research Board (MFM-IRB: R.24.5.2638), and written informed consent was obtained from all participants prior to enrollment.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eSample Size Considerations\u003c/h3\u003e\n\u003cp\u003eThe sample size was calculated to detect clinically meaningful differences in functional capacity between the study groups following breathing exercise\u0026ndash;based physiotherapy. Based on previous studies evaluating pulmonary rehabilitation and breathing exercises in patients with chronic obstructive pulmonary disease, an expected moderate effect size was assumed [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Using a two-sided significance level (α) of 0.05 and a statistical power of 80%, the minimum required sample size was estimated to be 88 patients. To enhance the statistical robustness of the study and account for potential dropouts, a total of 100 patients were enrolled and randomly allocated into two equal groups (50 patients each). Sample size calculation was performed using Power Analysis and Sample Size (PASS) software, version 8.0.\u003c/p\u003e\n\u003ch3\u003eStudy Population\u003c/h3\u003e\n\u003cp\u003e \u003cstrong\u003eInclusion criteria\u003c/strong\u003e \u003cp\u003ePatients were included if they fulfilled the diagnostic criteria of COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD), defined as post-bronchodilator FEV₁/FVC\u0026thinsp;\u0026lt;\u0026thinsp;0.70 with FEV₁ \u0026lt; 80% predicted [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Only clinically stable patients with no exacerbation or medication change for at least 30 days were included. All patients were ex-smokers and were receiving optimized medical therapy according to GOLD recommendations.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eExclusion criteria\u003c/strong\u003e \u003cp\u003ePatients were excluded if they were current smokers, unable to perform exercise testing, or had significant comorbidities, neuromuscular disorders, or diaphragmatic paralysis, or refusal to participate.\u003c/p\u003e \u003c/p\u003e\n\u003ch3\u003ePatient Screening and Group Allocation\u003c/h3\u003e\n\u003cp\u003eA total of 100 COPD patients were initially screened. Following application of eligibility criteria, patients were randomly allocated into two equal groups: Group I (Control Group): receiving optimized medical therapy only and Group II (intervention Group): receiving optimized medical therapy plus a structured breathing exercise\u0026ndash;based physiotherapy program. Both groups were reassessed after six months.\u003c/p\u003e\n\u003ch3\u003eClinical and Laboratory Assessment:\u003c/h3\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eClinical Assessment\u003c/h2\u003e \u003cp\u003eCollected demographic and clinical data included age, sex, smoking history (pack-years), and comorbidities such as cardiovascular disease, diabetes mellitus, and allergic rhinitis. Symptom severity was assessed using the modified Medical Research Council (mMRC) dyspnea scale.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eAll participants underwent baseline and post-intervention evaluation including:\u003c/h3\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003ePulmonary Function Testing using body plethysmography\u003c/h2\u003e \u003cp\u003eSpirometry was performed in accordance with ATS/ERS standards to measure post-bronchodilator FEV₁, forced vital capacity (FVC), and FEV₁/FVC ratio. COPD severity was classified according to GOLD staging.\u003c/p\u003e \u003cp\u003e\u003cspan type=\"BoldUnderline\" class=\"BoldUnderline\" name=\"Emphasis\"\u003eSix-minute walk test (6MWT)\u003c/span\u003e performed according to American Thoracic Society guidelines [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eLaboratory Assessments\u003c/h2\u003e \u003cdiv id=\"Sec12\" class=\"Section3\"\u003e \u003ch2\u003eArterial blood gas analysis (PaO₂, PaCO₂, SaO₂)\u003c/h2\u003e \u003cdiv id=\"Sec13\" class=\"Section4\"\u003e \u003ch2\u003eIntervention\u003c/h2\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e\n\u003ch3\u003eEducational Program\u003c/h3\u003e\n\u003cp\u003eBoth groups completed a standardized educational program prior to the intervention, consisting of 2 weekly sessions lasting 2 hours each. The program included disease pathophysiology, medication use, self-monitoring techniques, and strategies for environmental control and symptom management [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Both groups received identical educational sessions to isolate the physiological effect of breathing exercise\u0026ndash;based physiotherapy.\u003c/p\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eBreathing Exercise\u0026ndash;Based Physiotherapy\u003c/h2\u003e \u003cp\u003eIn addition to the educational program, the intervention group participated in a structured breathing exercise program focusing on:\u003c/p\u003e \u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eDiaphragmatic Breathing\u003c/b\u003e \u0026ndash; performed in supine and sitting positions to enhance abdominal expansion, slow respiratory flow, and increase expiratory efficiency.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003ePursed-Lip Breathing (PLB)\u003c/b\u003e \u0026ndash; to prolong exhalation, improve ventilatory control, and generate a small positive end-expiratory pressure, guided initially by the therapist and gradually performed independently.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eIncentive Spirometry\u003c/b\u003e \u0026ndash; using a flow-oriented device (e.g., Triflow) to encourage slow, deep inhalations with end-inspiratory breath hold, improving inspiratory capacity and ventilatory control.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e \u003cp\u003eThe program was delivered in progressive phases over six months, with intensity gradually increased every 8 sessions, while patients maintained their regular pharmacological regimen throughout the study [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eTreatment Pattern Assessment\u003c/h2\u003e \u003cp\u003ePatients received optimized medical treatment according to guidelines recommendations with selection according to patient indication and presence of non-indications or contraindications[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. COPD pharmacotherapy was documented, including long-acting β₂-agonists (LABA), long-acting muscarinic antagonists (LAMA), inhaled corticosteroids (ICS) alone or in combination with LABA, systemic corticosteroids (oral or intravenous), and combination regimens such as triple therapy (LABA/LAMA/ICS).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eOutcome Measures (Pre- and Post-intervention)\u003c/h2\u003e \u003cp\u003ePulmonary function was assessed before and after the intervention using spirometry, including forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC). Lung volumes, including residual volume (RV) and total lung capacity (TLC), were measured using body plethysmography. Gas exchange was evaluated using arterial blood gas analysis. Exercise capacity was assessed using the six-minute walk test, recording walking distance, heart rate, and peripheral oxygen saturation (SpO₂).\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eEthical considerations\u003c/strong\u003e \u003cp\u003e The study was approved by the Institutional Research Board of the Faculty of Medicine, Mansoura University (R.24. 5.2638). Written informed consent was obtained from all participants.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eStatistical analysis\u003c/strong\u003e \u003cp\u003eData were analyzed using SPSS version 22. Quantitative variables were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation or median (range). Between-group comparisons were performed using Student\u0026rsquo;s t-test or Mann\u0026ndash;Whitney test, and categorical variables were analyzed using the Chi-square test. A p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 100 patients with COPD were included in the analysis. There were no significant differences in age, sex, BMI, smoking status, or comorbidities between groups, confirming baseline comparability. (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [1]: \u0026nbsp;Sociodemographic characteristics of the studied patients.\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl group\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=50) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eintervention group (n=50) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003eAge (years)\u003cstrong\u003e\u0026nbsp;Mean \u0026plusmn; SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e58.3 \u0026plusmn; 9.3 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e59.9 \u0026plusmn; 8.8 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.42 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003eBMI (kg/m\u0026sup2;) \u003cstrong\u003eMean \u0026plusmn; SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e28.3 \u0026plusmn; 6.4 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e28.8 \u0026plusmn; 6.8 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.68 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSex\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;Male\u003cbr\u003e\u0026nbsp;Female\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e46 (92%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;4 (8%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e47 (94%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;3 (6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.81\u003c/p\u003e\n \u003cp\u003e0.79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking status\u003c/strong\u003e\u003cbr\u003e\u0026nbsp;Nonsmokers\u003cbr\u003e\u0026nbsp;passive smokers\u003c/p\u003e\n \u003cp\u003eEx- smokers\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e4 (8%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;7 (14%)\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e39 (78%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e2 (4%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;8 (16%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;40 (80%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.68\u003c/p\u003e\n \u003cp\u003e0.74\u003c/p\u003e\n \u003cp\u003e0.88 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\" style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking severity\u0026nbsp;\u003c/strong\u003e(among ex-smokers, n=79)\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eaccording to smoking index / pack-year exposure\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 41px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eMild \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003cbr\u003e\u0026nbsp;Moderate \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eSevere \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003eN=39\u003c/p\u003e\n \u003cp\u003e6 (15.3%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;24 (61.5%)\u003c/p\u003e\n \u003cp\u003e9 (23%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003eN=40\u003c/p\u003e\n \u003cp\u003e5 (12.5%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;25 (62.5%)\u003c/p\u003e\n \u003cp\u003e10 (25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.54\u003c/p\u003e\n \u003cp\u003e0.83\u003c/p\u003e\n \u003cp\u003e0.73 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eComorbidities\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003eHypertension (HTN) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eDiabetes mellitus (DM) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eIschemic heart disease (IHD)\u003c/p\u003e\n \u003cp\u003eChronic Liver disease\u003c/p\u003e\n \u003cp\u003eHistory of DVT\u003c/p\u003e\n \u003cp\u003eHistory of Pulmonary embolism (PE)\u003c/p\u003e\n \u003cp\u003eHistory of ischemic Stroke \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eControlled Atrial fibrillation (AF) \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003eBenign prostatic hyperplasia (BPH)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e30 (60%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;28 (56%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;8 (16%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;1 (2%)\u003c/p\u003e\n \u003cp\u003e1 (2%)\u003c/p\u003e\n \u003cp\u003e1 (2%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e3 (6%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e38 (76%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;35 (70%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;10 (20%)\u0026nbsp;\u003cbr\u003e\u0026nbsp;5 (10%)\u003c/p\u003e\n \u003cp\u003e4 (8%)\u003c/p\u003e\n \u003cp\u003e3 (6%)\u003c/p\u003e\n \u003cp\u003e3 (6%)\u003c/p\u003e\n \u003cp\u003e0 (0%)\u003c/p\u003e\n \u003cp\u003e2 (4%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.13\u003c/p\u003e\n \u003cp\u003e0.21\u003c/p\u003e\n \u003cp\u003e0.79\u003c/p\u003e\n \u003cp\u003e0.20\u003c/p\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003cp\u003e0.61\u003c/p\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003cp\u003e0.24\u003c/p\u003e\n \u003cp\u003e0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOverall Comorbidity Burden\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 41px;\"\u003e\n \u003cp\u003eCOPD only\u003cbr\u003e\u0026nbsp;COPD + Comorbidity\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e16 (32%)\u003cbr\u003e\u0026nbsp;34 (68%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e12 (24%)\u003cbr\u003e\u0026nbsp;38 (76%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 11px;\"\u003e\n \u003cp\u003e0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eAF: Atrial fibrillation; BMI: body mass index; BPH: Benign prostatic hyperplasia; COPD: chronic obstructive pulmonary disease; DM: diabetes mellitus; DVT, Deep venous thrombosis; HTN: hypertension; IHD: Ischemic heart disease; PE, Pulmonary Embolism; SD: Standard Deviation.\u003c/p\u003e\n\u003cp\u003eTable (2) illustrated that there were no significant differences observed in baseline respiratory symptoms, mMRC score, exacerbation rates and GOLD classifications between groups. Also, pharmacological treatment was balanced between the two groups, ensuring comparability.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [2]: Baseline Clinical and laboratory Characteristics, and Pharmacological\u003c/strong\u003e \u003cstrong\u003etreatment Profile of the Studied COPD Patients\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl group (n=50) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eintervention group\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(n=50) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eClinical severity\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedian (IQR)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedian (IQR)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003emMRc \u0026nbsp;dyspnea scale\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e3 (2-4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e3 (2-4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.88 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGOLD classification\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGOLD B\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eGOLD E\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e27 (54.0%) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e23 (46.0%) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e26 (52.0%) \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e24 (48.0%) \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.91\u003c/p\u003e\n \u003cp\u003e0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eExacerbations (per year), mean \u0026plusmn; SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e2.6 \u0026plusmn; 0.9 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e2.7 \u0026plusmn; 0.9 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.58 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSymptoms\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003eDyspnea\u003c/p\u003e\n \u003cp\u003eCough\u003c/p\u003e\n \u003cp\u003eExpectoration\u003c/p\u003e\n \u003cp\u003ewheezes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e50 (100%)\u003c/p\u003e\n \u003cp\u003e40(80%)\u003c/p\u003e\n \u003cp\u003e13(26%)\u003c/p\u003e\n \u003cp\u003e22(44%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e49 (98%)\u003c/p\u003e\n \u003cp\u003e36(72%)\u003c/p\u003e\n \u003cp\u003e12(24%)\u003c/p\u003e\n \u003cp\u003e19(38%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.82 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.34 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.88\u003c/p\u003e\n \u003cp\u003e0.53 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedication\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eN (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003esingle therapy\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eSABA\u003c/p\u003e\n \u003cp\u003eLABA\u003c/p\u003e\n \u003cp\u003eLAMA\u003c/p\u003e\n \u003cp\u003eICS\u003c/p\u003e\n \u003cp\u003eSystemic steroid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e23 (46%)\u003c/p\u003e\n \u003cp\u003e44 (88%)\u003c/p\u003e\n \u003cp\u003e18 (36%)\u003c/p\u003e\n \u003cp\u003e15 (30%)\u003c/p\u003e\n \u003cp\u003e14 (28%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e26 (52%)\u003c/p\u003e\n \u003cp\u003e48 (96%)\u003c/p\u003e\n \u003cp\u003e22 (44%)\u003c/p\u003e\n \u003cp\u003e18 (36%)\u003c/p\u003e\n \u003cp\u003e12 (24%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.21\u003c/p\u003e\n \u003cp\u003e0.18\u003c/p\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003cp\u003e0.51\u003c/p\u003e\n \u003cp\u003e0.65\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCombined therapy\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eLABA+LAMA\u003c/p\u003e\n \u003cp\u003eLABA+ICS\u003c/p\u003e\n \u003cp\u003eLABA+LAMA+ICS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e8 (16%)\u003c/p\u003e\n \u003cp\u003e5 (10%)\u003c/p\u003e\n \u003cp\u003e10 (20%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e10 (20%)\u003c/p\u003e\n \u003cp\u003e6 (12%)\u003c/p\u003e\n \u003cp\u003e12 (24%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.61\u003c/p\u003e\n \u003cp\u003e0.75\u003c/p\u003e\n \u003cp\u003e0.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 42px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCBC\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedian (IQR)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMedian (IQR)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003eEosinophils (%) \u0026nbsp;\u003c/p\u003e\n \u003cp\u003eNLR \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003ePLR\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e0.63 (0.04\u0026ndash;1.4) \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e4.3 (1.5\u0026ndash;6.1) \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.54 (0.09\u0026ndash;0.77)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e0.59 (0.02\u0026ndash;1.5) \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e4.3 (1.3\u0026ndash;7.2) \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.66 (0.05\u0026ndash;1.38)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.81\u003c/p\u003e\n \u003cp\u003e0.88\u003c/p\u003e\n \u003cp\u003e0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean \u0026plusmn; SD\u003c/strong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean \u0026plusmn; SD\u003c/strong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 42px;\"\u003e\n \u003cp\u003eNeutrophils (%)\u003c/p\u003e\n \u003cp\u003eLymphocytes (%)\u003c/p\u003e\n \u003cp\u003eHemoglobin (g/dL)\u003c/p\u003e\n \u003cp\u003ePlatelets (\u0026times;10\u0026sup3;/\u0026micro;L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e70.6 \u0026plusmn; 13.3\u003c/p\u003e\n \u003cp\u003e21.5 \u0026plusmn; 9.0 \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e12.8 \u0026plusmn; 1.8 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e251 \u0026plusmn; 96 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e68.9 \u0026plusmn; 15.1\u003c/p\u003e\n \u003cp\u003e21.6 \u0026plusmn; 10.2 \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e12.7 \u0026plusmn; 1.6 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e249 \u0026plusmn; 92 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.55\u003c/p\u003e\n \u003cp\u003e0.97\u003c/p\u003e\n \u003cp\u003e0.77\u003c/p\u003e\n \u003cp\u003e0.89\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData are presented as mean \u0026plusmn; standard deviation (SD), median (interquartile range, IQR), or number (percentage), as appropriate. mMRC, modified Medical Research Council; GOLD, Global Initiative for Chronic Obstructive Lung Disease; LABA, long-acting \u0026beta;₂-agonist; LAMA, long-acting muscarinic antagonist; ICS, inhaled corticosteroids; SABA, short-acting \u0026beta;₂-agonist.; SD: Standard Deviation. NLR: Neutrophil/ lymphocyte ratio; PLR: Platelet/Lymphocyte Ratio\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable (3) demonstrated that breathing exercise\u0026ndash;based physiotherapy led to significant improvements in pH, pO₂, and SaO₂\u0026nbsp;and reduction of pCO₂\u0026nbsp;compared with controls, reflecting enhanced gas exchange.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [3]: ABG parameters (Baseline \u0026plusmn; Follow-up) in COPD Patients\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"106%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 18px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eABG Parameter\u003c/strong\u003e\u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12px;\"\u003e\n \u003cp\u003eControl group (Baseline)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12px;\"\u003e\n \u003cp\u003eControl group (Follow-up)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eintervention group (Baseline)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003eintervention group (Follow-up)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003ep-value (group comparison)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 18px;\"\u003e\n \u003cp\u003ePH\u003c/p\u003e\n \u003cp\u003epCO₂ (mmHg)\u003c/p\u003e\n \u003cp\u003eHCO₃⁻ (mmol/L)\u003c/p\u003e\n \u003cp\u003epO₂ (mmHg)\u003c/p\u003e\n \u003cp\u003eSaO₂ (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12px;\"\u003e\n \u003cp\u003e7.37 \u0026plusmn; 0.04\u003c/p\u003e\n \u003cp\u003e46 \u0026plusmn; 7\u003c/p\u003e\n \u003cp\u003e27 \u0026plusmn; 4\u003c/p\u003e\n \u003cp\u003e68 \u0026plusmn; 13\u003c/p\u003e\n \u003cp\u003e91 \u0026plusmn; 5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12px;\"\u003e\n \u003cp\u003e7.38 \u0026plusmn; 0.04\u003c/p\u003e\n \u003cp\u003e44 \u0026plusmn; 6\u003c/p\u003e\n \u003cp\u003e27 \u0026plusmn; 3\u003c/p\u003e\n \u003cp\u003e73 \u0026plusmn; 12\u003c/p\u003e\n \u003cp\u003e93 \u0026plusmn; 4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e0.42\u003c/p\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003cp\u003e0.44\u003c/p\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003cp\u003e0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e7.37 \u0026plusmn; 0.04\u003c/p\u003e\n \u003cp\u003e45 \u0026plusmn; 6 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e28 \u0026plusmn; 4\u003c/p\u003e\n \u003cp\u003e70 \u0026plusmn; 12 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e92 \u0026plusmn; 6 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e7.41 \u0026plusmn; 0.03\u003c/p\u003e\n \u003cp\u003e41 \u0026plusmn; 5\u003c/p\u003e\n \u003cp\u003e26 \u0026plusmn; 3\u003c/p\u003e\n \u003cp\u003e78 \u0026plusmn; 10\u003c/p\u003e\n \u003cp\u003e95 \u0026plusmn; 4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e0.02\u003c/p\u003e\n \u003cp\u003e0.03\u003c/p\u003e\n \u003cp\u003e0.05\u003c/p\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003cp\u003e0.05\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e0.04 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.05 \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.12 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.03 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.04 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eABG: arterial blood gas; pCO₂: partial pressure of carbon dioxide; pO₂: partial pressure of oxygen; SaO₂: arterial oxygen saturation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable (4) disclosed that there was Significant improvements in FEV₁\u0026nbsp;and FVC were observed in the intervention group compared to controls, supporting functional benefit. Furthermore, Physiotherapy reduced air trapping (RV, RV/TLC) and slightly increased TLC, indicating improved lung mechanics. Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive value of baseline spirometric parameters. ROC curve analysis demonstrated that baseline FEV₁\u0026nbsp;(%) was a significant predictor of response to breathing exercises in COPD patients (AUC = 0.76 (95% CI: 0.65\u0026ndash;0.87), p \u0026lt; 0.001). A cutoff value of approximately 55% predicted provided the best balance between sensitivity and specificity (figure 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [4]: Spirometer and Lung volumes parameters (Baseline \u0026plusmn; Follow-up) in COPD Patients\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"108%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpirometer Parameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003eControl group (Baseline)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (Follow-up)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003eintervention group (Baseline)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003eintervention group (Follow-up)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003ep-value (group comparison)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17px;\"\u003e\n \u003cp\u003eFEV1/FVC\u003c/p\u003e\n \u003cp\u003eFEV1 (%)\u003c/p\u003e\n \u003cp\u003eFVC (%)\u003c/p\u003e\n \u003cp\u003eMMEF25-75 (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e55 \u0026plusmn; 10 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e61 \u0026plusmn; 13\u003c/p\u003e\n \u003cp\u003e71 \u0026plusmn; 15\u003c/p\u003e\n \u003cp\u003e48 \u0026plusmn; 12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e56 \u0026plusmn; 9\u003c/p\u003e\n \u003cp\u003e63 \u0026plusmn; 12\u003c/p\u003e\n \u003cp\u003e73 \u0026plusmn; 13\u003c/p\u003e\n \u003cp\u003e49 \u0026plusmn; 11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e0.87\u003c/p\u003e\n \u003cp\u003e0.31\u003c/p\u003e\n \u003cp\u003e0.40\u003c/p\u003e\n \u003cp\u003e0.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 13px;\"\u003e\n \u003cp\u003e54\u0026plusmn;9 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 62 \u0026plusmn; 12\u003c/p\u003e\n \u003cp\u003e72 \u0026plusmn; 14\u003c/p\u003e\n \u003cp\u003e47 \u0026plusmn; 13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e58 \u0026plusmn; 8 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e70 \u0026plusmn; 10\u003c/p\u003e\n \u003cp\u003e79 \u0026plusmn; 12\u003c/p\u003e\n \u003cp\u003e60 \u0026plusmn; 12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.02 \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 17px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLung volumes\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003eRV (%)\u003c/p\u003e\n \u003cp\u003eTLC (%)\u003c/p\u003e\n \u003cp\u003eRV\\TLC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e95 \u0026plusmn; 13 \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e102 \u0026plusmn; 14\u003c/p\u003e\n \u003cp\u003e0.51\u0026plusmn;0.11 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e92 \u0026plusmn; 12\u003c/p\u003e\n \u003cp\u003e103 \u0026plusmn; 13\u003c/p\u003e\n \u003cp\u003e0.49 \u0026plusmn; 0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003cp\u003e0.62\u003c/p\u003e\n \u003cp\u003e0.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e92 \u0026plusmn; 12\u003c/p\u003e\n \u003cp\u003e101 \u0026plusmn; 15 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.52 \u0026plusmn; 0.12 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e78 \u0026plusmn; 10\u003c/p\u003e\n \u003cp\u003e104 \u0026plusmn; 13 \u003c/p\u003e\n \u003cp\u003e0.42 \u0026plusmn; 0.10 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003cp\u003e0.04\u003c/p\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eA \u003cem\u003ep\u003c/em\u003e value \u0026lt; 0.05 was considered statistically significant. FEV₁, forced expiratory volume in one second; FVC, forced vital capacity; MMEF, maximal mid-expiratory flow; \u0026nbsp;RV, residual volume; TLC, total lung capacity.\u003c/p\u003e\n\u003cp\u003eBased on a predefined clinically meaningful threshold, patients were classified into responders and non-responders according to post-physiotherapy improvement in FEV₁. Thirty-seven patients (74%) were classified as responders, achieving an increase in FEV₁\u0026nbsp;\u0026ge;12% following breathing exercise\u0026ndash;based physiotherapy [6, 11], whereas 13 patients (26%) were classified as non-responders. Responders demonstrated a significantly greater improvement in FEV₁, supporting its role as a key functional marker of treatment response. Although reductions in RV/TLC were observed in both groups, a greater magnitude of improvement was observed in the overall intervention group compared with controls, without reaching statistical significance, suggesting comparable improvements in air trapping. Similarly, both responders and non-responders showed clinically meaningful increases in six-minute walk distance, without significant differences between groups. These findings support the presence of distinct responder and non-responder phenotypes, with FEV₁\u0026nbsp;emerging as the most sensitive parameter for discriminating treatment response (Table 5).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [5]: Responder and non-responder analysis in the intervention group\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eResponder\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e(n=37)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-responder\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e(n=13)\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eP value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo. of patients (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e37 patients (74%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e13 patients (26%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003eBaseline FEV1 (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e53.7 \u0026plusmn; 20.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e48.7 \u0026plusmn; 15.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003eFollow-up FEV₁ (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e63.9 \u0026plusmn; 24.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e54.0 \u0026plusmn; 17.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003e\u0026Delta;FEV₁ (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e18.9 \u0026plusmn; 3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e10.9 \u0026plusmn; 0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003eBaseline 6MWT (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e355.5\u0026plusmn; 87.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e344.0\u0026plusmn; 77.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003eFollow-up 6MWT (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e404.2\u0026plusmn; 49.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e409.2\u0026plusmn; 41.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.72\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003e\u0026Delta;6MWT (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e48.8\u0026plusmn;92.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e65.2\u0026plusmn;84.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003eBaseline RV/TLC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e0.49\u0026plusmn; 0.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e0.45\u0026plusmn; 0.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.54\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 32px;\"\u003e\n \u003cp\u003eFollow-up RV/TLC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 25px;\"\u003e\n \u003cp\u003e0.41\u0026plusmn; 0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e0.44\u0026plusmn; 0.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 32px;\"\u003e\n \u003cp\u003e\u0026Delta;RV/TLC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 25px;\"\u003e\n \u003cp\u003e\u0026minus;0.11\u0026plusmn;0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 30px;\"\u003e\n \u003cp\u003e\u0026minus;0.08\u0026plusmn;0.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 11px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eData are presented as \u003cstrong\u003emean \u0026plusmn; standard deviation (SD);\u0026nbsp;\u003c/strong\u003eResponders were defined as patients achieving an increase in FEV₁ \u0026ge;12% from baseline following breathing exercise\u0026ndash;based physiotherapy; \u003cstrong\u003e\u0026Delta;\u003c/strong\u003e indicates change from baseline to follow-up; FEV₁, forced expiratory volume in one second; FVC, forced vital capacity; 6MWT = six-minute walk test;; \u0026nbsp;RV, residual volume; TLC, total lung capacity.\u003c/p\u003e\n\u003cp\u003eTable (6) shows that 6MWT distance and SpO₂ improved significantly in the intervention group, confirming enhanced exercise capacity.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [6]: 6MWT parameters (Baseline \u0026plusmn; Follow-up) in COPD Patients\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"108%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameter\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12px;\"\u003e\n \u003cp\u003eControl group (Baseline)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003eControl group (Follow-up)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12px;\"\u003e\n \u003cp\u003eintervention group (Baseline)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003eintervention group (Follow-up)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003eP value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003ep-value (group comparison)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003eDistance (m) \u0026nbsp;SaO₂ mean (%)\u003c/p\u003e\n \u003cp\u003eHR mean (bpm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12px;\"\u003e\n \u003cp\u003e362 \u0026plusmn; 82 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 95 \u0026plusmn; 3\u003c/p\u003e\n \u003cp\u003e105 \u0026plusmn; 14 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e375 \u0026plusmn; 79 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 95 \u0026plusmn; 2 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e104 \u0026plusmn; 13 \u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7px;\"\u003e\n \u003cp\u003e0.34\u003c/p\u003e\n \u003cp\u003e0.77\u003c/p\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 12px;\"\u003e\n \u003cp\u003e326 \u0026plusmn; 80 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 94 \u0026plusmn; 3 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e104 \u0026plusmn; 15 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 13px;\"\u003e\n \u003cp\u003e399 \u0026plusmn; 85 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 96 \u0026plusmn; 2 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e99 \u0026plusmn; 12 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 9px;\"\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003cp\u003e0.001\u003c/p\u003e\n \u003cp\u003e0.002\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 15px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003cp\u003e0.002 \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e0.04 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*p \u0026lt; 0.05 was considered statistically significant 6MWT = six-minute walk test; SaO₂: arterial oxygen saturation; HR= Heart rate.\u003c/p\u003e\n\u003cp\u003eTable (7) displayed that Physiotherapy strengthened correlations between lung function, gas exchange, and exercise capacity, demonstrating a physiological link between improvements in mechanics and functional performance.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable [7]: Correlation between pulmonary function and 6MWT in intervention group (Baseline versus Follow-up)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariable 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e\u003cstrong\u003er (Baseline)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e\u003cstrong\u003er (Follow-up)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003eFEV₁ \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.48 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e0.01 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e0.65 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e\u0026lt;0.001 \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003eFVC \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.42 \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e0.02 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e0.60 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e0.001 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 20px;\"\u003e\n \u003cp\u003eFEV₁/FVC \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.31 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e0.05 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e0.42 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.01 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eRV/TLC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e-0.40 \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.008 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e-0.52 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.002 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eSaO₂ \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.03 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e0.48 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.004 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003epCO₂\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003eFEV₁ \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e-0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 10px;\"\u003e\n \u003cp\u003e0.06 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e-0.39 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.02 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eRV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003eFEV₁ \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e-0.43 \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.005 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e-0.55 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.001 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eTLC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.30 \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.05 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e0.41 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.01 \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eHR Mean \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 22px;\"\u003e\n \u003cp\u003e6MWT Distance\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e-0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.08 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e-0.35 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 10px;\"\u003e\n \u003cp\u003e0.03 \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eFEV1: Forced expiratory volume at 1st second; 6MWT = six-minute walk test; SaO₂: arterial oxygen saturation; HR= Heart rate; pCO₂: partial pressure of carbon dioxide; RV, residual volume; TLC, total lung capacity.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;*p \u0026lt; 0.05 was considered statistically significant\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis randomized controlled trial investigated the isolated effect of a structured breathing exercise\u0026ndash;based physiotherapy program in patients with stable chronic obstructive pulmonary disease. The main findings demonstrate that adding breathing-focused physiotherapy to optimized medical treatment leads to significant improvements in gas exchange, pulmonary function, lung volumes, and exercise capacity compared with optimized medical therapy alone. Importantly, this study provides evidence that breathing exercises, even when applied without comprehensive pulmonary rehabilitation programs, can induce clinically and physiologically meaningful benefits in COPD patients.\u003c/p\u003e \u003cp\u003eCOPD is increasingly understood as a multisystem disease characterized by airflow limitation, respiratory muscle dysfunction, impaired gas exchange, and reduced exercise tolerance, all of which contribute to disability and poor prognosis [\u003cspan additionalcitationids=\"CR2 CR3\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. While pharmacological therapy remains the cornerstone of symptom control and exacerbation prevention, its effect on ventilatory mechanics and functional capacity is limited, particularly in patients with advanced disease [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Consequently, non-pharmacological interventions such as pulmonary rehabilitation have gained a central role in comprehensive COPD management [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMost previous studies evaluating pulmonary rehabilitation have focused on multidisciplinary programs incorporating aerobic exercise training, resistance training, education, and breathing techniques [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. These studies consistently demonstrated improvements in dyspnea, exercise tolerance, and quality of life; however, the contribution of individual components\u0026mdash;particularly breathing exercises\u0026mdash;has remained unclear. The present study addresses this gap by isolating breathing exercise\u0026ndash;based physiotherapy as the primary intervention, allowing a more precise evaluation of its physiological and functional effects.\u003c/p\u003e \u003cp\u003eThe significant improvement in arterial blood gas parameters observed in the intervention group reflects enhanced ventilatory efficiency and alveolar ventilation. These findings are in agreement with earlier studies by Thomas et al. [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], who reported that breathing retraining techniques improve ventilatory control and reduce dyspnea in patients with obstructive airway diseases. Similarly, pursed-lip breathing has been shown to prolong expiration, reduce expiratory flow limitation, and alleviate dynamic hyperinflation, resulting in improved oxygenation and reduced carbon dioxide retention [8]. The present study extends these observations by demonstrating that such physiological benefits translate into measurable improvements in arterial blood gases within a randomized controlled design.\u003c/p\u003e \u003cp\u003eRegarding pulmonary function, the observed improvements in FEV₁ and FVC in the intervention group contrast with the minimal or absent changes typically reported with pharmacological therapy alone [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Previous rehabilitation studies have reported modest spirometric improvements, often attributed to reduced hyperinflation rather than true reversal of airflow obstruction, [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The significant improvement in MMEF25\u0026ndash;75% suggests enhanced small airway function, which may partially explain the observed reduction in air trapping and improvement in exercise capacity.\u003c/p\u003e \u003cp\u003eIn line with this concept, the current study demonstrated significant reductions in residual volume and RV/TLC ratio, suggesting decreased air trapping and improved lung mechanics. These findings support the hypothesis that breathing exercises enhance expiratory efficiency and diaphragmatic function, thereby improving lung volume distribution rather than directly altering airway caliber.\u003c/p\u003e \u003cp\u003eThe role of diaphragmatic dysfunction in COPD has been well documented using imaging and physiological studies [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Smargiassi et al. [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e] demonstrated impaired diaphragmatic mobility and thickness in COPD patients, which correlated with disease severity and dyspnea. While that study focused on diagnostic assessment, the present trial provides interventional evidence that targeted breathing exercises can partially reverse the functional consequences of diaphragmatic impairment, as reflected by improved lung volumes and ventilatory indices.\u003c/p\u003e \u003cp\u003eExercise intolerance is a hallmark of COPD and a strong predictor of morbidity and mortality [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. In the current study, the intervention group showed a significant increase in six-minute walk distance, accompanied by improved oxygen saturation and a more favorable heart rate response. These improvements exceeded the minimal important difference for the six-minute walk test reported by Holland et al. [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e11\u003c/span\u003e], underscoring their clinical significance.\u003c/p\u003e \u003cp\u003ePrevious pulmonary rehabilitation studies have attributed improvements in exercise capacity primarily to peripheral muscle conditioning and cardiovascular adaptations [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. However, the present findings suggest that improving ventilatory efficiency alone\u0026mdash;through breathing-focused physiotherapy\u0026mdash;can substantially enhance exercise performance. This observation is particularly relevant for patients who are unable to participate in high-intensity exercise training due to comorbidities or severe dyspnea.\u003c/p\u003e \u003cp\u003eA distinctive strength of this study lies in the correlation analysis between pulmonary function, gas exchange, and exercise capacity. At baseline, correlations between spirometric parameters, lung volumes, arterial blood gases, and six-minute walk distance were modest, reflecting the complex and multifactorial nature of exercise limitation in COPD. Following physiotherapy, these correlations became stronger and more consistent, particularly between FEV₁, RV/TLC, SaO₂, and walking distance. This finding suggests that breathing exercise\u0026ndash;based physiotherapy improves not only individual physiological parameters but also the functional integration between respiratory mechanics and exercise performance. Few previous studies have explored how rehabilitation modifies the relationships between physiological variables [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The strengthening of correlations between pulmonary function parameters (particularly FEV₁ and RV/TLC) and six-minute walk distance after intervention further supports that responders achieved physiologically meaningful improvements that translated into functional capacity.\u003c/p\u003e \u003cp\u003eImportantly, responder status was not associated with baseline demographic characteristics, body mass index, comorbidity burden, baseline symptoms, or pharmacological treatment, suggesting that response to breathing exercise\u0026ndash;based physiotherapy is driven primarily by physiological reserve rather than clinical profile. ROC curve analysis revealed that baseline FEV₁ (%) has good discriminatory ability for predicting response to breathing exercises. This finding suggests that baseline spirometric assessment may serve as a simple, clinically applicable tool to identify patients most likely to benefit from breathing-focused physiotherapy, allowing more individualized and efficient implementation of non-pharmacological interventions. The concept of heterogeneous responses to rehabilitation is consistent with previous pulmonary rehabilitation literature describing responder and non-responder phenotypes among COPD patients [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe responder analysis further emphasizes the heterogeneous nature of response to breathing exercise\u0026ndash;based physiotherapy in COPD. Despite comparable improvements in exercise capacity, only a subset of patients achieved a clinically meaningful improvement in airflow limitation and lung hyperinflation. This finding is consistent with previous pulmonary rehabilitation literature describing responder and non-responder phenotypes and inter-individual variability in treatment response [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Although baseline characteristics were comparable between responders and non-responders, responders demonstrated a significantly greater improvement in FEV₁, supporting its role as a key functional marker of response to breathing exercise\u0026ndash;based physiotherapy. Importantly, correlation analysis showed that post-intervention pulmonary function parameters, particularly FEV₁ and RV/TLC, were more strongly associated with six-minute walk distance compared with baseline. This finding suggests that responders achieved physiologically meaningful improvements in ventilatory mechanics and reduced air trapping that translated into functional exercise capacity.\u003c/p\u003e \u003cp\u003eHowever, non-responders, despite showing clinically relevant improvements in six-minute walk distance, did not exhibit comparable physiological changes, indicating that functional gains alone may not fully reflect underlying ventilatory improvement. Together, these findings support the presence of distinct responder and non-responder phenotypes and highlight FEV₁ as the most sensitive parameter for discriminating meaningful treatment response.\u003c/p\u003e \u003cp\u003eIn contrast, the control group receiving optimized medical therapy alone showed no significant improvements in pulmonary function, gas exchange, or exercise capacity. This finding aligns with GOLD recommendations, which acknowledge that bronchodilators and inhaled corticosteroids primarily improve symptoms and exacerbation rates but have limited effects on exercise tolerance and lung mechanics in stable COPD [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The lack of significant physiological change in the control group further emphasizes the added value of breathing exercise\u0026ndash;based physiotherapy beyond standard pharmacological management.\u003c/p\u003e \u003cp\u003eHence, these results have important clinical implications. Breathing exercise\u0026ndash;based physiotherapy represents a low-cost, safe, and easily implementable intervention that can be incorporated into routine COPD care, even in resource-limited settings. Unlike comprehensive pulmonary rehabilitation programs, which require specialized equipment and multidisciplinary teams, breathing-focused physiotherapy can be delivered in outpatient clinics or at home with minimal supervision. This makes it particularly attractive for healthcare systems with limited access to full rehabilitation services. Moreover, the ability to identify responders using baseline FEV₁ may further enhance the cost-effectiveness and clinical impact of this intervention by targeting patients most likely to benefit.\u003c/p\u003e \u003cp\u003eThis multidimensional analysis strengthens causal inference by linking physiological improvement to functional outcomes. However, Future studies with larger cohorts and multivariable analyses are warranted to identify demographic and clinical predictors of response and to support personalized physiotherapy strategies in COPD patients.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eAddition of a structured breathing exercise\u0026ndash;based physiotherapy program to optimized medical therapy results in significant improvements in gas exchange, pulmonary function, and exercise capacity in patients with stable chronic obstructive pulmonary disease. These findings support the role of breathing-focused physiotherapy as an effective and clinically relevant adjunctive intervention, contributing to improved physiological efficiency and functional performance beyond pharmacological treatment alone\u003c/p\u003e \u003cdiv id=\"Sec22\" class=\"Section2\"\u003e \u003ch2\u003eLimitations\u003c/h2\u003e \u003cp\u003eThis study has limitations. First, the study was conducted at a single center, which may limit the generalizability of the findings to broader COPD populations. Second, the follow-up period was relatively short, and long-term sustainability of the observed improvements could not be assessed. Third, although the study focused on isolating the effect of breathing exercise\u0026ndash;based physiotherapy, quality-of-life measures and patient-reported outcomes were not included, which could have provided additional insight into the clinical impact of the intervention. Finally, the absence of direct measurements of diaphragmatic function or dynamic hyperinflation during exercise limits mechanistic interpretation of the observed improvements.\u003c/p\u003e \u003cdiv id=\"Sec23\" class=\"Section3\"\u003e \u003ch2\u003eRecommendations\u003c/h2\u003e \u003cp\u003eStructured breathing exercise\u0026ndash;based physiotherapy should be considered an effective adjunct to optimized medical therapy in stable COPD patients, particularly for improving gas exchange and exercise tolerance. Future studies should include multicenter designs with larger sample sizes and longer follow-up periods to assess the durability of benefits. Incorporation of patient-reported outcomes, diaphragmatic imaging, and dynamic assessments during exercise may further elucidate the mechanisms underlying physiotherapy-induced improvements. Additionally, comparative studies evaluating breathing-focused physiotherapy against comprehensive pulmonary rehabilitation programs may help optimize individualized rehabilitation strategies in COPD management\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eABG\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eArterial Blood Gases\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eAF\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eAtrial Fibrillation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eBMI\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBody Mass Index\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eBPH\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eBenign Prostatic Hyperplasia\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eCOPD\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eChronic Obstructive Pulmonary Disease\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eDM\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eDiabetes Mellitus\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eDVT\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eDeep Venous Thrombosis\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eFEV₁\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eForced Expiratory Volume in the First Second\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eFVC\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eForced Vital Capacity\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eGOLD\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eGlobal Initiative for Chronic Obstructive Lung Disease\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eHTN\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eHypertension\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eICS\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eInhaled Corticosteroids\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eIHD\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eIschemic Heart Disease\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eLABA\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLong-Acting β₂-Agonist\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eLAMA\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eLong-Acting Muscarinic Antagonist\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003emMRC\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eModified Medical Research Council Dyspnea Scale\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003epCO₂\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePartial Pressure of Carbon Dioxide\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003ePE\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePulmonary Embolism\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003epO₂\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePartial Pressure of Oxygen\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eRV\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eResidual Volume\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eSaO₂\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eArterial Oxygen Saturation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eSD\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eStandard Deviation\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e\u0026bull; \u003cb\u003eTLC\u003c/b\u003e\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eTotal Lung Capacity\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":" \u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\u003cp\u003e \u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e \u003cp\u003e This study was approved by the research ethics committee of the chest medicine department of the Faculty of Medicine at Mansoura University. Reference number of approval: R.24. 5.2638.\u003c/p\u003e \u003ch2\u003e Consent for publication\u003c/b\u003e:\u003c/h2\u003e \u003cp\u003eAll patients included in this study gave written informed consent to publish the data contained in this study.\u003c/p\u003e \u003ch2\u003e Competing interests\u003c/b\u003e:\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e \u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eNot applicable (no funding was received for this study).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eMAM and MAI conceived and designed the study. MAM and MRB performed patient enrollment and data collection. MAM analyzed the data and drafted the manuscript. MAM, MAI, and MRB critically reviewed and revised the manuscript for important intellectual content. All authors read and approved the final version of the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgement:\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAvailable on request with the corresponding author.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eL\u0026oacute;pez-Campos, J. L., Tan, W., \u0026amp; Soriano, J. B. (2016). Global burden of COPD. \u003cem\u003eRespirology, 21\u003c/em\u003e(1), 14\u0026ndash;23. https://doi.org/10.1111/resp.12660\u003c/li\u003e\n \u003cli\u003eBrassington, K., Selemidis, S., Bozinovski, S., \u0026amp; Vlahos, R. (2019). Comorbid cardiovascular disease in chronic obstructive pulmonary disease. \u003cem\u003eClinical Science, 133\u003c/em\u003e(8), 885\u0026ndash;904. https://doi.org/10.1042/CS20180764\u003c/li\u003e\n \u003cli\u003eFischer, B. M., Pavlisko, E., \u0026amp; Voynow, J. A. (2011). Pathogenic triad in COPD: Oxidative stress, protease\u0026ndash;antiprotease imbalance, and inflammation. \u003cem\u003eInternational Journal of Chronic Obstructive Pulmonary Disease, 6\u003c/em\u003e, 413\u0026ndash;421. https://doi.org/10.2147/COPD.S10770\u003c/li\u003e\n \u003cli\u003eSmargiassi, A., Inchingolo, R., Tagliaboschi, L., Di Marco, F., Valente, S., \u0026amp; Corbo, G. M. (2014). Ultrasonographic assessment of the diaphragm in chronic obstructive pulmonary disease. \u003cem\u003eRespiration, 87\u003c/em\u003e(5), 364\u0026ndash;371. https://doi.org/10.1159/000358672\u003c/li\u003e\n \u003cli\u003eSpruit, M. A., \u0026amp; Singh, S. J. (2013). Pulmonary rehabilitation: Key concepts. \u003cem\u003eChest, 144\u003c/em\u003e(3), 1091\u0026ndash;1093. https://doi.org/10.1378/chest.13-1028\u003c/li\u003e\n \u003cli\u003eRochester, C. L., Vogiatzis, I., Holland, A. E., et al. (2015). An official American Thoracic Society/European Respiratory Society policy statement: Pulmonary rehabilitation. \u003cem\u003eAmerican Journal of Respiratory and Critical Care Medicine, 192\u003c/em\u003e(11), 1373\u0026ndash;1386. https://doi.org/10.1164/rccm.201510-1966ST\u003c/li\u003e\n \u003cli\u003eThomas, M., McKinley, R. K., Freeman, E., \u0026amp; Foy, C. (2003). Breathing retraining for dysfunctional breathing in asthma and chronic obstructive pulmonary disease: A randomized controlled trial. \u003cem\u003eThorax, 58\u003c/em\u003e(2), 110\u0026ndash;115. https://doi.org/10.1136/thorax.58.2.110\u003c/li\u003e\n \u003cli\u003eNguyen, J., \u0026amp; Duong, H. (2020).\u0026nbsp;\u003cem\u003ePursed-lip breathing\u003c/em\u003e. In StatPearls. StatPearls Publishing.\u003cbr\u003e\u0026nbsp;https://www.ncbi.nlm.nih.gov/books/NBK545289/\u003c/li\u003e\n \u003cli\u003eWatchie, J. (2010). \u003cem\u003eCardiovascular and pulmonary physical therapy: Evidence and practice\u003c/em\u003e (2nd ed.). Saunders Elsevier.\u003c/li\u003e\n \u003cli\u003eNishiyama, O., Taniguchi, H., Kondoh, Y., et al. (2005). Factors that maintain the long-term benefits of pulmonary rehabilitation in patients with COPD. \u003cem\u003eQuality of Life Research, 14\u003c/em\u003e(10), 2315\u0026ndash;2321. https://doi.org/10.1007/s11136-005-8418-4\u003c/li\u003e\n \u003cli\u003eHolland, A. E., Hill, C. J., Rasekaba, T., Lee, A., Naughton, M. T., \u0026amp; McDonald, C. F. (2010). Updating the minimal important difference for six-minute walk distance in patients with chronic obstructive pulmonary disease. \u003cem\u003eArchives of Physical Medicine and Rehabilitation, 91\u003c/em\u003e(2), 221\u0026ndash;225. https://doi.org/10.1016/j.apmr.2009.10.017\u003c/li\u003e\n \u003cli\u003eGlobal Initiative for Chronic Obstructive Lung Disease. (2024). \u003cem\u003eGlobal strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease\u003c/em\u003e. GOLD. https://goldcopd.org\u003c/li\u003e\n \u003cli\u003eATS Committee on Proficiency Standards for Clinical Pulmonary Function Laboratories. (2002). ATS statement: Guidelines for the six-minute walk test. \u003cem\u003eAmerican Journal of Respiratory and Critical Care Medicine, 166\u003c/em\u003e(1), 111\u0026ndash;117. https://doi.org/10.1164/ajrccm.166.1.at1102\u003c/li\u003e\n \u003cli\u003eSpruit, M. A., Singh, S. J., Garvey, C., et al. (2013). An official American Thoracic Society/European Respiratory Society statement: Key concepts and advances in pulmonary rehabilitation. \u003cem\u003eAmerican Journal of Respiratory and Critical Care Medicine, 188\u003c/em\u003e(8), e13\u0026ndash;e64. https://doi.org/10.1164/rccm.201309-1634ST\u003c/li\u003e\n \u003cli\u003eJones, S. E., Green, S. A., Clark, A. L., et al. (2014). Pulmonary rehabilitation following acute exacerbation of COPD: A randomized controlled trial. \u003cem\u003eThorax, 69\u003c/em\u003e(2), 181\u0026ndash;186. https://doi.org/10.1136/thoraxjnl-2013-203808\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"chronic obstructive pulmonary disease, breathing exercises, pulmonary rehabilitation, physiotherapy","lastPublishedDoi":"10.21203/rs.3.rs-8725910/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8725910/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cem\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e:\u003c/em\u003e \u003cbr\u003e\n Chronic obstructive pulmonary disease (COPD) is a progressive disorder marked by persistent airflow limitation and systemic manifestations, including respiratory muscle dysfunction and reduced exercise tolerance. Breathing-based physiotherapy is a key component of pulmonary rehabilitation, yet its isolated effects on functional and physiological outcomes remain incompletely defined.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eObjective\u003c/strong\u003e\u003c/em\u003e\u003cbr\u003e\n to evaluate the effectiveness of a structured breathing exercise–based physiotherapy program in patients with stable COPD, compared with standard medical therapy alone\u003c/p\u003e\n\u003cp\u003e.\u003cem\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThis randomized clinical trial at Mansoura University Hospitals (October 2024–2025), 100 clinically stable COPD patients were allocated to a control group receiving optimized medical therapy or an intervention group receiving medical therapy plus structured breathing exercises. Pre- and post-intervention assessments included arterial blood gases (PaO₂, PaCO₂, SaO₂), pulmonary function tests, body mass index, and six-minute walk test (6MWT).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eResults: \u003c/strong\u003e\u003c/em\u003e\u003cbr\u003e\n The intervention group showed significant improvements compared with controls. Mean 6MWT increased from 326 ± 80 m to 399 ± 85 m (p \u0026lt; 0.001), while the control group showed insignificant change (362 ± 82 m to 375 ± 79 m; p = 0.34). FEV₁ improved from 62 ± 12% to 70 ± 10% (p \u0026lt; 0.001) and FVC from 72 ± 14% to 79 ± 12% (p \u0026lt; 0.001); controls had nonsignificant changes. PaO₂ increased (70 ± 12 to 78 ± 10 mmHg; p = 0.04), SaO₂ improved (92 ± 6% to 95 ± 4%; p = 0.05), and PaCO₂ decreased (45 ± 6 to 41 ± 5 mmHg; p = 0.03) in the intervention group.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e:\u003c/em\u003e\u003cbr\u003e\nStructured breathing exercise–based physiotherapy significantly enhances exercise capacity, pulmonary function, and gas exchange in stable COPD when added to standard medical therapy, supporting its integration into routine management.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eTrial registration\u003c/strong\u003e\u003c/em\u003e\u003cem\u003e: \u003c/em\u003eClinicalTrials.gov identifier: NCT06472167\u003c/p\u003e","manuscriptTitle":"Added Value of Adjuvant Breathing-Based Physiotherapy in the Management of Patients with Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-11 17:03:42","doi":"10.21203/rs.3.rs-8725910/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"60e575cb-df2a-44ef-948a-1b341e5c89d6","owner":[],"postedDate":"February 11th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-02T05:55:15+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-11 17:03:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8725910","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8725910","identity":"rs-8725910","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}