Correlation between segmental Phase Angles and motor function of DMD children and predictive value of Phase angels for lower limb motor function loss

Correlation between segmental Phase Angles and motor function of DMD children and predictive value of Phase angels for lower limb motor function loss | 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 Correlation between segmental Phase Angles and motor function of DMD children and predictive value of Phase angels for lower limb motor function loss Qin Hu, Xiaoyong Chen, Shaojie Luo, Yanhong Wang, Peicong Fan, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3892999/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: Duchenne muscular dystrophy (DMD) is a prevalent X-linked recessive muscle degeneration disorder that involves the gradual loss of functional muscle mass. The Phase Angle (PhA) can indicate changes in cell membrane integrity and intercellular space. It has been recognized as a valuable tool for assessing disease severity and predicting patient outcomes. However, there is limited research on the application of PhA in children with neuromuscular diseases, including DMD. Objective： we investigated the relationship between Phase Angle (PhA) and motor function in children with DMD. We specifically examined the correlation between segmental PhAs and motor function and evaluated the effectiveness of segmental PhAs as a measure for assessing motor function in DMD children Method: 399 DMD patients were divided into loss of lower limb motor function group (n = 57) and preserve lower limb motor function group (n = 342). The correlation between PhA and motor function were analyzed through spearman correlation analysis. The predictive value of PhA and PhA combining age for lower limb motor function loss was analyzed by ROC curve. Result: TR-PhA reaches its peak at 6 years old, while other PhAs reaches its peak at 5-6years old and subsequently declines over time. There was a significant correlation between PhAs and the NSAA score, with the strongest correlation observed in leg PhA (r=0.753, P<0.001). ROC curve was used and showed that PhAs (LA, RA, LL, RL, TR, and whole) can predict the loss of lower limb function in DMD children (AUC from 0.725 to 0.863).The corresponding cut-off PhA values were 2.55°, 2.95°, 2.65°, 2.55°, 4.25°, and 2.85°, respectively. Additionally, PhAs combined with age had more excellent predictive ability for lower limb function loss than PhAs((AUC from 0.929 to 0.951). Conclusion: The time of peak of PhAs are earlier than NNSA score (peak at 6-7years old). PhAs in legs demonstrate the strongest correlation and highest predictive value for lower limb motor function loss. PhA could serve as a simple, fast, and non-invasive marker to predict the loss of lower limb motor function in DMD children. Duchenne muscular dystrophy phase angle children motor function Figures Figure 1 Figure 2 Figure 3 Figure 4 1. Introduction Duchenne muscular dystrophy (DMD) is an x-linked recessive muscle degenerative disease that affects approximately 1 in 5,000 to 1 in 6,000 live male births [1]. It is characterized by the rapid and irreversible replacement of normal skeletal muscle with connective and adipose tissue, resulting in the loss of motor function and muscle degeneration. Unfortunately, the prognosis for DMD patients is poor, with many succumbing to heart failure or respiratory failure in their twenties. Extensive research has demonstrated that the underlying cause of DMD is a defect in the dystrophin protein [1,2] . The absence of dystrophin renders muscle cell membranes unstable and more susceptible to mechanical damage [1,2] . This instability leads to uncontrolled calcium influx, inflammation, necrosis, and the replacement of muscle tissue with fibrotic tissue and fat, resulting in severe muscle wasting and weakness [3] . It has been shown that therapies targeting the restoration of dystrophin expression or improvement of membrane stability can effectively mitigate the symptoms of DMD. Therefore, assessing muscle cell membrane function may serve as an indicator of DMD progression. Bioelectrical impedance analysis (BIA) is a useful method for assessing body composition in different populations. In recent studies, particular attention has been given to phase angle (PhA) as it has been identified as a relevant indicator of cellular health, body cell mass, and the integrity of the cell membrane [4,5] . It has also been suggested as a potential marker of muscle mass in skeletal and muscular diseases. Previous research has demonstrated that a lower phase angle is associated with reduced muscle mass in conditions such as sarcopenia (age-related muscle loss), cachexia (muscle wasting associated with chronic disease), and muscular dystrophy. In addition to its role in assessing muscle mass, phase angle has also been investigated as a marker of muscle function. Studies have shown that phase angle is associated with muscle strength and physical function decline [ 6,7] . However, the relationship between phase angle and the decline of muscle function in children with Duchenne muscular dystrophy (DMD) remains unclear. Therefore, the objective of this study was to evaluate the relationship between phase angle (PhA) and motor function parameters in DMD patients. Additionally, we aimed to determine the threshold of phase angle that can predict motor function in DMD patients. We believe that PhA could serve as a useful and convenient indicator to evaluate the loss of ambulatory function. 2. Methods 2.1 Participants In this study, a total of 399 patients diagnosed with DMD through muscle histopathology or genetic evaluation using multiplex ligation-dependent probe amplification were recruited. Exclusion criteria were applied to ensure data quality and patient safety. The exclusion criteria included: (1) patients with poor cognitive ability who could not be effectively evaluated, (2) patients with incomplete data, (3) patients with a metal stent or metal device in their body, and (4) patients with ascites or edema of the limbs. The recruited patients were then divided into two groups based on the loss of ambulation function. The study protocol was approved by the Ethics Committee of West China Second Hospital, and all enrolled patients provided informed consent. 2.2 Data collection In this study, we collected various patient information, including age, gender, disease, and diagnosis. Bioelectrical impedance and phase angle measurements were obtained using an Inbody device (Biospace) to assess body composition. This included measurements of skeletal muscle, percentage of fat and body fat, visceral fat area, phase angle, and body cell volume. The phase angle (°) was calculated using the formula: arctangent (reactance/resistance × 180/π). In our investigation, we specifically focused on segmental phase angles in patients with DMD, including the right arm (RA), left arm (LA), right leg (RL), left leg (LL), trunk (TR), and whole body (Whole). To evaluate ambulatory performance in children with DMD, we utilized the North Star Ambulatory Assessment (NSAA) scale. This scale consists of 17 items and was designed to measure changes in gross motor ability. Scores on the NSAA scale range from 0 to 34, with higher scores indicating better motor function. 2.3 Statistical analysis Quantitative variables with a normal distribution were expressed as means and standard deviations, and variables that did not meet the Gaussian model were presented as interquartile ranges. The relationship between PhA and North Star Ambulatory Assessment（NSAA）was analyzed using the Pearson correction coefficient. ROC curves and areas under the curve (AUCs) were used determine the cut-off values of PhA on the loss of the ambulation function in DMD children. The cutoff value for maximizing the sensitivity and specificity for each analyses was calculated using the Youden index. All statistical analyses were performed using SPSS 25.0 software, with a two-sided P value of ＜0.05 indicating statistical significance. 3. Results 3.1 Participant Characteristics A total of 399 male patients with DMD were enrolled in this study. The age range of the participants was from 3 years to 17 years and 6 months, with a median age of 8 years old. The anthropometric and bioimpedance parameters, along with phase angle (PhA) values, are presented in Table 1. When analyzing the phase angle results across different age groups, we observed that TR-PhA reached its peak at5- 6 years old, while other segmental PhAs reached its peak about 5 years old (Figure 3). However, as shown in Figure 4, all PhAs declined over time after reaching their respective peaks(Table 2 and Figure 3). Table.1 BIA result of Patient With DMD Median (IQR) Age (yr) 8.00 (5.00 to 10.00) BMI (kg/m2) 17.00 (15.70 to19.50) ICW (L) 7.60 (6.60 to 8.90) ECW (L) 5.10 (4.40 to 6.00) SMM (kg) 8.00 (6.60 to 9.60) FFM (kg) 17.50 (15.10 to 20.40) BFM (kg) 5.20 (3.60 to 11.70) PBF (%) 24.80 (18.10 to 37.30) VFA (cm2) 33.60 (23.40 to 81.50) SMI (kg/m2) 3.20 (2.70 to 3.90) BCM (kg) 11.00 (9.40 to 12.70) BMR (kcal) 747.00 (695.00 to 811.00) LA-PhA (°) 2.90 (2.50 to 3.30) RA-PhA (°) 2.90 (2.50 to 3.20) LL-PhA (°) 3.00 (2.50 to 3.60) RL-PhA (°) 3.00 (2.50 to 3.50) TR-PhA (°) 5.20 (4.25 to 6.20) Whole-PhA (°) 3.00 (2.60 to 3.50) NNSA score 16.00 (7.00 to 24.00) Table.2 PhAs and NNSA Score change with age Age(yr) 3 4 5 6 7 （n=17） （n=49） （n=45） （n=37） （n=44） RA-PhA（°） 2.68±0.27 3.04±0.50 3.23±0.64 3.18±0.68 3.03±0.56 LA-PhA（°） 2.77±0.47 3.07±0.55 3.14±0.60 3.06±0.52 3.02±0.50 RL-PhA（°） 2.94±0.25 3. 07±0.51 3.50±0.80 3.53±0.79 3.43±1.01 LL-PhA（°） 2.92±0.30 3.08±0.52 3.49±0.78 3.48±0.81 3.44±1.00 TR-PhA（°） 4.68±0.74 5.72±1.13 5.78±1.31 5.81±1.09 5.71±1.13 Whole body-PhA（°） 2.85±0.23 3.14±0.41 3.42±0.59 3.40±0.66 3.27±0.68 NNSA Score 13.00±4.78 16.88±5.03 20.78±6.26 23.65±6.81 22.50±9.18 Age(yr) 8 9 10 11 ≥12 （n=42） （n=39） （n=46） （n=32） （n=38） RA-PhA（°） 3.09±0.61 2.78±0.53 2.81±0.50 2.89±0.66 2.63±0.69 LA-PhA（°） 3.04±0.38 2.72±0.61 2.80±0.49 3.05±1.15 2.55±0.77 RL-PhA（°） 3.27±1.00 3.01±1.10 2. 85±0.75 2. 85±0.96 2.16±0.58 LL-PhA（°） 3.29±0.98 3.04±1.08 2.90±0.77 2.90±0.84 2.10±0.54 TR-PhA（°） 5.22±1.16 4.91±1.17 4.95±1.51 4.78±2.21 4.57±2.35 Whole body-PhA（°） 3.23±0.70 2.94±0.71 2.90±0.55 2.93±0.66 2.49±0.55 NNSA Score 20.26±9.82 13.82±10.61 13.29±10.07 11.88±10.76 0.84±1.443 3.2 Associations between PhAs and NNSA total score In the Pearson correlation analysis, we observed that all segmental phase angles (PhAs) and the whole-body PhA were positively correlated with the North Star Ambulatory Assessment (NSAA) total score. Notably, the correlation coefficients of the segmental PhAs in the legs were higher compared to those of the other segments. The relationship between PhAs and the NSAA total score is summarized in Table 3. Specifically, both LL-PhA and RL-PhA demonstrated a strong and identical correlation with the NSAA total score (r = 0.753, p < 0.001). On the other hand, TR-PhA exhibited weaker correlations with the NSAA total score (|r| ≤ 0.50). For a visual representation of these correlations, refer to Figure 1, which presents the scatter plot of the PhAs. Table.3 Correlation coefficient between PhAs and NNSA total score NNSA Score r P LA-PhA 0.536 <0.001 RA-PhA 0.549 <0.001 LL-PhA 0.753 <0.001 RL-PhA 0.753 <0.001 TR-PhA 0.360 <0.001 Whole body-PhA 0.714 <0.001 3.3 Comparison of phase Angle results between the two groups and its prediction of lower limb motor function loss in DMD children We divided the DMD children into two groups based on their motor function: group 1 (preserved ambulation function) and group 2 (loss of ambulation function). Significant differences were observed in age, North Star Ambulatory Assessment (NSAA) scores, and segmental phase angles between the two groups. To further assess the potential of phase angles (PhAs) in predicting lower limb motor function loss in DMD children, we performed receiver operating characteristic (ROC) curve analysis. Figure 4 displays the ROC curves for predicting lower limb motor function loss using PhA values. The corresponding area under the curve (AUC) values for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA were 0.726, 0.725, 0.832, 0.863, 0.813, and 0.704, respectively(Table 5). Based on the ROC curve analysis, we identified optimal cutoff points for each segmental PhA to predict lower limb motor function loss. The cutoff points were determined as follows: 2.95° for RA-PhA, 2.55° for LA-PhA, 2.55° for RL-PhA, 2.65° for LL-PhA, 2.85° for whole-PhA, and 4.25° for TR-PhA. We also performed the ROC curve of combination of PhA and age.The combined prediction ROC curve results are presented in the figure4(b). The areas under the ROC curves for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA, when combined with age to predict the loss of lower limb motor function, were determined to be 0.933, 0.929, 0.944, 0.951, 0.943, and 0.932, respectively. These results indicate that all the indexes possess high predictive values for the loss of lower limb motor function in DMD patients (all P<0.001). Notably, the combined prediction value of LL-PhA and age demonstrated the highest predictive capability. The result show that the combination of PhA and age compared to PhAs alone provide more accurate predictive value. Table 4.Comparison of phase Angle results between the two groups Group 1（ N=342) Group 2（ N=57） P Age(yr) 7.00（5.00，9.00） 12.00（10.50,14.00） <0.001 NNSA score 19.00（12.00，25.00） 1.00（0.00，1.00） <0.001 LA-PhA（°） 2.90(2.60,3.30) 2.50(2.10,2.85) <0.001 RL-PhA（°） 3.00(2.60,3.40) 2.50(2.20,2.85) <0.001 LL-PhA（°） 3.20±0.85 2.20(1.70,2.50) <0.001 RL-PhA（°） 3.24±0.84 2.10(1.80,2.60) <0.001 TR-PhA（°） 5.30(4.50,6.20) 4.00(3.25,5.20) <0.001 Whole-PhA（°） 3.10(2.70,3.55) 2.50（2.10，2.70） <0.001 Table.5 ROC curve utilized to evaluate the PhAs for the lower limb motor function loss. Cut-off AUC 95%CI sensitivity % specificity % P LA-PhA 2.55 0.725 0.645 0.804 59.6 62.2 0.00 RA-PhA 2.95 0.726 0.654 0.797 86 50.6 0.00 LL-PhA 2.65 0.863 0.812 0.915 84.2 76.3 0.00 RL-PhA 2.55 0.832 0.772 0.892 73.7 80.1 0.00 TR-PhA 4.25 0.704 0.613 0.794 59.6 80.9 0.00 WB-PhA 2.85 0.813 0.752 0.875 84.2 68.1 0.00 4. Discussion Duchenne muscular dystrophy (DMD) is a prevalent X-linked recessive muscle degeneration disorder characterized by progressive loss of functional muscle mass over time [6-8] . The disease follows a natural history that includes a gradual decline in muscle function, leading to the loss of independent ambulation in teenage years and eventual dependence on assistance for mobility and daily activities. Bioelectrical impedance analysis (BIA) is based on the principle of treating the human body as a conductive cylinder. It utilizes the electrical properties of intracellular and extracellular fluids, as well as cell membranes, to measure resistance (R) and capacitive reactance (Xc) at different electrical frequencies. These measurements are then used to estimate body composition and changes through empirical regression equations. Phase Angle (PhA) reflects the health status of cells by assessing the integrity of cell membranes and the conductive properties of fluids, providing insights into tissue and organ function. PhA is considered a comprehensive indicator of nutrition, inflammation, and immunity in assessing disease severity and patient prognosis [9,10] . Previous studies have demonstrated a positive association between PhA and muscle strength [11,12] , leading to its wide discussion and application in sarcopenia. High PhA has been correlated with better muscle function in sarcopenia patients [13] . Conversely, lower PhA has been associated with increased disease severity, decreased quadriceps strength in knee and hip osteoarthritis patients [14,15] , and reduced quadriceps strength and walking speed in older adults [8] . In the context of DMD, a study by Karina M evaluated anthropometric and bioimpedance parameters in 43 individuals with DMD, revealing lower PhA values compared to reference values in DMD boys. However, the use of PhA for assessing motor function in children with DMD is rarely described. In clinical practice and scientific research, the North Star Ambulatory Assessment (NSAA) is commonly employed to specifically measure ambulatory performance in children with DMD [16-18] . This research studies the relationship between them. Our findings demonstrate a consistent trend between the NNSA score and PhAs, indicating a correlation between motor function and PhA in DMD. The Pearson correlation analysis revealed that all segmental PhAs and the whole-PhA were positively associated with the NNSA total score. Notably, the correlation coefficient of segmental PhAs in the legs was higher compared to other segments. A Brazilian study investigating changes in PhA across different age groups (1-80 years) demonstrated an age-dependent pattern, with PhA increasing during childhood, stabilizing during most of adulthood, and decreasing in late adulthood [19] . In our study, we observed that PhAs reached their peak around five to six years of age and subsequently declined. This trend is significantly different from that observed in the normal population. Additionally, we found that the NSAA total score gradually declined over time after six to seven years old, consistent with previous reports in the literature [20,21] . In the typical course of DMD, patients begin to exhibit abnormal gait at around three years of age. Initially, motor development continues, but they gradually encounter difficulties in climbing, running, jumping, and standing up. Signs such as Gower sign, lordosis, and bilateral gastrocnemius pseudohypertrophy may become evident. After the plateau period between five and seven years old, motor abilities begin to regress. In our study, we observed that PhAs decline at 5-6 years old, earlier than the change observed in the NNSA score at 6-7 years old. This suggests that PhA may reflect changes in muscle cell function earlier than changes in motor function, indicating its potential as a predictor of clinical motor function. Furthermore, we found that the loss of lower limb motor function was closely related to the WB-PhA and the segmental PhAs. ROC curve analysis demonstrated that PhAs have predictive ability for the loss of lower limb function in children with DMD. The areas under the ROC curves for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA predict the loss of lower limb motor function were 0.726, 0.725, 0.832, 0.863, 0.813, and 0.704, respectively. This indicates that PhAs, particularly the PhA in legs, can serve as indicators to evaluate the loss of lower limb motor function in children with DMD and even as markers to assess the degree of lower limb muscle injury. We further analyzed the ROC curve of PhA combined with age, which revealed that both PhAs and PhAs combined with age had predictive ability for the loss of lower limb function in DMD children. The areas under the ROC curves for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA combined with age to predict the loss of lower limb motor function were 0.933, 0.929, 0.944, 0.951, 0.943, and 0.932, respectively. These results indicate that all the indexes possess high predictive values for the loss of lower limb motor function in DMD patients (all P<0.001). PhA in legs combined with age exhibited the highest predictive values for the loss of lower limb motor function in DMD patients. The combination of PhA and age compared to PhAs alone provide more accurate predictive value. It is also important to acknowledge several limitations of our study. First, we did not have data on muscle strength, other motor parameters, and muscle pathology, which could have provided further insights into the relationship between PhAs and motor function in DMD children. Second, our study design was cross-sectional, meaning that we could not establish causal relationships between PhAs and motor function. Future research should include larger cohorts and prospective studies to explore these relationships in more depth. Third, our sample size for participants aged 12 years and older was insufficient to analyze the trend of phase Angle in older children. In future studies, it would be valuable to investigate the correlation between PhA and muscle pathological changes, muscle strength, and other motor function parameters. In conclusion, our findings suggest that PhAs are associated with motor function in DMD children, and PhAs, especially when combined with age, have predictive ability for the loss of lower limb function. PhA could potentially serve as a simple, fast, and non-invasive marker to predict the loss of lower limb motor function in children with DMD. Abbreviations BMI body mass index ICW intracellular water ECW extracellular water SMM skeletal muscle mass FFM fat-free mass BFM body fat mass PBF percentage of body fat VFA visceral fat area SMI skeletal muscle index BCM body cell mass BMR Basal metabolic rate LA-PhA left arm phase angle RA -PhA right arm phase angle LL-PhA left leg phase angle RL-PhA right leg phase angle TR-PhA trunk phase angle WB-PhA whole body phase angle NNSA North Star Ambulatory Assessment ROC curve Receiver operating characteristic curve Declarations Ethics approval and consent to participate and Consent for publication The research protocol was reviewed and approved by the Research Ethics Committee of West China Second Hospital of Sichuan University.This retrospective study was carried out using the opt-out method for the caseseries of our hospital and was conducted in accordance with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Informed consent was waived by our Institutional Review Board because of the retrospective nature of our study. This study was approved by the Medical Ethics Committee of West China Second University Hospital (2023(091)), Sichuan University, Chengdu, China. Availability of data and materials The datasets used and analysed during the current study are available from the corresponding author on reasonable request. Conflict of interest Qin Hu, Xiaoyong Chen, Shaojie Luo, YanhongWang, Peicong Fan, Xiaona Wu, Hui Zhou1 Huayan Xu, Na Li, and Xiaotang Cai declare that they have no conflicts of interest. Funding This study was supported by the Sichuan Science and Technology Support Program(2023YFG0284), the Chengdu Municipal Health Commission Project(21PJ048) and Science and Technology Department of Sichuan Province( 23ZDYF0395). Authors' contributions All authors were involved in the design of the study. Also, they participate in data collection, statistical analysis and data interpretation, write the submitted articles, and complete the final approval of the submitted version. Acknowledgements Thanks to our team, the days we work together are happy and the days we struggle together are unforgettable. Thank you to every colleague for all the effort they put into this project. References Hoffman EP, Brown RH Jr,Kunkel LM. Dystrophin: the protein product of the Duchenne muscular dystrophy locus. Cell 987;51919-928. Petrof BJ, Shrager JB, Stedman HH， Kelly AM，Sweeney HL. Dystrophin protects the sarcolemma from stresses developed during muscule contraction. Proc NatlAcad Sci USA 1993;90: 3710-3714. Bettica P, Petrini S, D'Oria V, et al. Histological effects of givinostat in boys with Duchenne muscular dystrophy. Neuromuscul Disord. 2016;26(10):643-649. doi:10.1016/j.nmd.2016.07.002 Akamatsu Y, Kusakabe T, Arai H, et al. 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Long term natural history data in ambulant boys with Duchenne muscular dystrophy: 36-month changes. PLoS One. 2014;9(10): e108205. pmid:25271887; PubMed Central PMCID: PMC4182715. 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-3892999","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":270395162,"identity":"e4c8800c-b680-4d6f-a0aa-b7b256169b0b","order_by":0,"name":"Qin Hu","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Qin","middleName":"","lastName":"Hu","suffix":""},{"id":270395163,"identity":"e443e564-a874-4195-b193-d56bc580b800","order_by":1,"name":"Xiaoyong Chen","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Xiaoyong","middleName":"","lastName":"Chen","suffix":""},{"id":270395164,"identity":"cbb60a48-3ba8-46ab-ac11-e3c31c2b938a","order_by":2,"name":"Shaojie Luo","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Shaojie","middleName":"","lastName":"Luo","suffix":""},{"id":270395165,"identity":"14fb9f5e-b122-42f9-af8a-1df0571219b4","order_by":3,"name":"Yanhong Wang","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Yanhong","middleName":"","lastName":"Wang","suffix":""},{"id":270395166,"identity":"625a28f1-4621-4eed-87d7-11b81529eddb","order_by":4,"name":"Peicong Fan","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Peicong","middleName":"","lastName":"Fan","suffix":""},{"id":270395167,"identity":"c734ae3e-b582-4d61-b0bf-19e23a38f9d6","order_by":5,"name":"Xiaona Wu","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Xiaona","middleName":"","lastName":"Wu","suffix":""},{"id":270395168,"identity":"c60b9182-0247-4063-9de0-6fb863f77d3c","order_by":6,"name":"Hui Zhou","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Hui","middleName":"","lastName":"Zhou","suffix":""},{"id":270395169,"identity":"f44c0fff-88a7-41bb-8efe-15cc214a7d85","order_by":7,"name":"Huayan Xu","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Huayan","middleName":"","lastName":"Xu","suffix":""},{"id":270395170,"identity":"9956f09f-cc73-4e78-b211-16105db9ae0b","order_by":8,"name":"Na Li","email":"","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":false,"prefix":"","firstName":"Na","middleName":"","lastName":"Li","suffix":""},{"id":270395171,"identity":"79371941-a9bd-40a6-b593-5e3ddcefae6b","order_by":9,"name":"Xiaotang Cai","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwUlEQVRIiWNgGAWjYLCChAobOX5m5oMPiFTPzMDw4EyasWQ7W7IB0VoYH7YdTtxwnsdMgCgN/DPyDzAkArVsPsxgxsBQYxNNUIvEmcNAv5xLN952mCHtAcOxtNwGQloM2JuBWsqsZYFajhswNhwmQgsz0PsJbMyMm5sZ2ySI0wK2pc1ZcQMzMxtxWoB+MWBIAAayxGE2ZoMEYvzCPyPxAeMPUFT2n//44EONDWEtQMD+A85MIEL5KBgFo2AUjAIiAAAgzzv3JbxwQAAAAABJRU5ErkJggg==","orcid":"","institution":"West China Second University Hospital of Sichuan University (WCSUH- SCU)","correspondingAuthor":true,"prefix":"","firstName":"Xiaotang","middleName":"","lastName":"Cai","suffix":""}],"badges":[],"createdAt":"2024-01-24 05:30:55","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3892999/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3892999/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":50576902,"identity":"84123aeb-6b70-4852-83e3-c948b3b020ff","added_by":"auto","created_at":"2024-02-02 17:52:44","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":320847,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelation analysis of PhA and NNSA（a-f: LA-PhA，RA-PhA，TR-PhA，LL-PhA，RL-PhA，WB-PhA）\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-3892999/v1/7fba942acfd521495079f304.png"},{"id":50576899,"identity":"209b64b4-4224-46a1-a9e1-87749614a23b","added_by":"auto","created_at":"2024-02-02 17:52:44","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":110377,"visible":true,"origin":"","legend":"\u003cp\u003eScatter plot and fitted curve of NNSA score changes with age\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-3892999/v1/dd600a504ec7b424e09ba658.png"},{"id":50577561,"identity":"a9385e9b-29bc-4813-acbe-f1b0614585da","added_by":"auto","created_at":"2024-02-02 18:00:44","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":430465,"visible":true,"origin":"","legend":"\u003cp\u003eScatter plot and fiitted curve of different PhAs change with age（a-f: LA-PhA，RA-PhA，TR-PhA，LL-PhA，RL-PhA，WB-PhA）\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-3892999/v1/100158d2bf447407e7081dc1.png"},{"id":50576900,"identity":"36aee664-496f-441f-80d2-e05dc32c4129","added_by":"auto","created_at":"2024-02-02 17:52:44","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":79759,"visible":true,"origin":"","legend":"\u003cp\u003e(a) ROC curve utilized to evaluate the PhAs for the lower limb motor function loss. (b) ROC curve utilized to evaluate the PhAs combine age for the lower limb motor function loss.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-3892999/v1/b0015acca120b29ef0c0f283.png"},{"id":54509920,"identity":"0eaf9546-74d8-46d8-9eb9-203dd9c9baa5","added_by":"auto","created_at":"2024-04-11 15:18:02","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":945447,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3892999/v1/11d3d5fa-4d7e-46cf-a672-41512a527a8a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Correlation between segmental Phase Angles and motor function of DMD children and predictive value of Phase angels for lower limb motor function loss","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eDuchenne muscular dystrophy (DMD) is an x-linked recessive muscle degenerative disease that affects approximately 1 in 5,000 to 1 in 6,000 live male births [1]. It is characterized by the rapid and irreversible replacement of normal skeletal muscle with connective and adipose tissue, resulting in the loss of motor function and muscle degeneration. Unfortunately, the prognosis for DMD patients is poor, with many succumbing to heart failure or respiratory failure in their twenties. Extensive research has demonstrated that the underlying cause of DMD is a defect in the dystrophin protein \u003csup\u003e[1,2]\u003c/sup\u003e. The absence of dystrophin renders muscle cell membranes unstable and more susceptible to mechanical damage \u003csup\u003e[1,2]\u003c/sup\u003e. This instability leads to uncontrolled calcium influx, inflammation, necrosis, and the replacement of muscle tissue with fibrotic tissue and fat, resulting in severe muscle wasting and weakness\u003csup\u003e\u0026nbsp;[3]\u003c/sup\u003e. It has been shown that therapies targeting the restoration of dystrophin expression or improvement of membrane stability can effectively mitigate the symptoms of DMD. Therefore, assessing muscle cell membrane function may serve as an indicator of DMD progression.\u003c/p\u003e\n\u003cp\u003eBioelectrical impedance analysis (BIA) is a useful method for assessing body composition in different populations. In recent studies, particular attention has been given to phase angle (PhA) as it has been identified as a relevant indicator of cellular health, body cell mass, and the integrity of the cell membrane\u003csup\u003e[4,5]\u003c/sup\u003e. It has also been suggested as a potential marker of muscle mass in skeletal and muscular diseases. Previous research has demonstrated that a lower phase angle is associated with reduced muscle mass in conditions such as sarcopenia (age-related muscle loss), cachexia (muscle wasting associated with chronic disease), and muscular dystrophy. In addition to its role in assessing muscle mass, phase angle has also been investigated as a marker of muscle function. Studies have shown that phase angle is associated with muscle strength and physical function decline [\u003csup\u003e6,7]\u003c/sup\u003e. However, the relationship between phase angle and the decline of muscle function in children with Duchenne muscular dystrophy (DMD) remains unclear. Therefore, the objective of this study was to evaluate the relationship between phase angle (PhA) and motor function parameters in DMD patients. Additionally, we aimed to determine the threshold of phase angle that can predict motor function in DMD patients. We believe that PhA could serve as a useful and convenient indicator to evaluate the loss of ambulatory function.\u003c/p\u003e"},{"header":"2. Methods","content":"\u003cp\u003e2.1 Participants\u003c/p\u003e\n\u003cp\u003eIn this study, a total of 399 patients diagnosed with DMD through muscle histopathology or genetic evaluation using multiplex ligation-dependent probe amplification were recruited. Exclusion criteria were applied to ensure data quality and patient safety. The exclusion criteria included: (1) patients with poor cognitive ability who could not be effectively evaluated, (2) patients with incomplete data, (3) patients with a metal stent or metal device in their body, and (4) patients with ascites or edema of the limbs. The recruited patients were then divided into two groups based on the loss of ambulation function. The study protocol was approved by the Ethics Committee of West China Second Hospital, and all enrolled patients provided informed consent.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.2 Data collection\u003c/p\u003e\n\u003cp\u003eIn this study, we collected various patient information, including age, gender, disease, and diagnosis. Bioelectrical impedance and phase angle measurements were obtained using an Inbody device (Biospace) to assess body composition. This included measurements of skeletal muscle, percentage of fat and body fat, visceral fat area, phase angle, and body cell volume. The phase angle (\u0026deg;) was calculated using the formula: arctangent (reactance/resistance \u0026times; 180/\u0026pi;). In our investigation, we specifically focused on segmental phase angles in patients with DMD, including the right arm (RA), left arm (LA), right leg (RL), left leg (LL), trunk (TR), and whole body (Whole). To evaluate ambulatory performance in children with DMD, we utilized the North Star Ambulatory Assessment (NSAA) scale. This scale consists of 17 items and was designed to measure changes in gross motor ability. Scores on the NSAA scale range from 0 to 34, with higher scores indicating better motor function.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.3 Statistical analysis\u003c/p\u003e\n\u003cp\u003eQuantitative variables with a normal distribution were expressed as means and standard deviations, and variables that did not meet the Gaussian model were presented as interquartile ranges. The relationship between PhA and North Star Ambulatory Assessment（NSAA）was analyzed using the Pearson correction coefficient. ROC curves and areas under the curve (AUCs) were used determine the cut-off values of PhA on the loss of the ambulation function in DMD children. The cutoff value for maximizing the sensitivity and specificity for each analyses was calculated using the Youden index. All statistical analyses were performed using SPSS 25.0 software, with a two-sided P value of ＜0.05 indicating statistical significance.\u003c/p\u003e"},{"header":"3.\tResults","content":"\u003cp\u003e3.1 Participant Characteristics\u003c/p\u003e\n\u003cp\u003eA total of 399 male patients with DMD were enrolled in this study. The age range of the participants was from 3 years to 17 years and 6 months, with a median age of 8 years old. The anthropometric and bioimpedance parameters, along with phase angle (PhA) values, are presented in Table 1. When analyzing the phase angle results across different age groups, we observed that TR-PhA reached its peak at5- 6 years old, while other segmental PhAs reached its peak about 5 years old (Figure 3). However, as shown in Figure 4, all PhAs declined over time after reaching their respective peaks(Table 2 and Figure 3).\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"2\"\u003e\n \u003cp\u003eTable.1 BIA result of Patient With DMD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"null\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"null\"\u003eMedian (IQR)\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eAge (yr)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e8.00 (5.00 to 10.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eBMI (kg/m2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e17.00 (15.70 to19.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eICW (L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e7.60 (6.60 to 8.90)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eECW (L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e5.10 (4.40 to 6.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eSMM (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e8.00 (6.60 to 9.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eFFM (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e17.50 (15.10 to 20.40)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eBFM (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e5.20 (3.60 to 11.70)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003ePBF (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e24.80 (18.10 to 37.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eVFA (cm2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e33.60 (23.40 to 81.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eSMI (kg/m2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e3.20 (2.70 to 3.90)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eBCM (kg)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e11.00 (9.40 to 12.70)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eBMR (kcal)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e747.00 (695.00 to 811.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eLA-PhA (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e2.90 (2.50 to 3.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eRA-PhA (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e2.90 (2.50 to 3.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eLL-PhA (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e3.00 (2.50 to 3.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eRL-PhA (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e3.00 (2.50 to 3.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eTR-PhA (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e5.20 (4.25 to 6.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eWhole-PhA (\u0026deg;)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e3.00 (2.60 to 3.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"40%\"\u003e\n \u003cp\u003eNNSA score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"60%\"\u003e\n \u003cp\u003e16.00 (7.00 to 24.00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable.2 PhAs and NNSA Score change with age\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"5\"\u003e\n \u003cp\u003eAge(yr)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=17）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=49）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=45）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=37）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=44）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRA-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.68\u0026plusmn;0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.04\u0026plusmn;0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.23\u0026plusmn;0.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.18\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.03\u0026plusmn;0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLA-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.77\u0026plusmn;0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.07\u0026plusmn;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.14\u0026plusmn;0.60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.06\u0026plusmn;0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.02\u0026plusmn;0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.94\u0026plusmn;0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3. 07\u0026plusmn;0.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.50\u0026plusmn;0.80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.53\u0026plusmn;0.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.43\u0026plusmn;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.92\u0026plusmn;0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.08\u0026plusmn;0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.49\u0026plusmn;0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.48\u0026plusmn;0.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.44\u0026plusmn;1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eTR-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.68\u0026plusmn;0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.72\u0026plusmn;1.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.78\u0026plusmn;1.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.81\u0026plusmn;1.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.71\u0026plusmn;1.13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eWhole body-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.85\u0026plusmn;0.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.14\u0026plusmn;0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.42\u0026plusmn;0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.40\u0026plusmn;0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.27\u0026plusmn;0.68\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNNSA Score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e13.00\u0026plusmn;4.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e16.88\u0026plusmn;5.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20.78\u0026plusmn;6.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e23.65\u0026plusmn;6.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e22.50\u0026plusmn;9.18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd colspan=\"5\"\u003e\n \u003cp\u003eAge(yr)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026ge;12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=42）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=39）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=46）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=32）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e（n=38）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRA-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.09\u0026plusmn;0.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.78\u0026plusmn;0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.81\u0026plusmn;0.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.89\u0026plusmn;0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.63\u0026plusmn;0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLA-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.04\u0026plusmn;0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.72\u0026plusmn;0.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.80\u0026plusmn;0.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.05\u0026plusmn;1.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.55\u0026plusmn;0.77\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.27\u0026plusmn;1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.01\u0026plusmn;1.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2. 85\u0026plusmn;0.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2. 85\u0026plusmn;0.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.16\u0026plusmn;0.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.29\u0026plusmn;0.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.04\u0026plusmn;1.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.90\u0026plusmn;0.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.90\u0026plusmn;0.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.10\u0026plusmn;0.54\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eTR-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.22\u0026plusmn;1.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.91\u0026plusmn;1.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.95\u0026plusmn;1.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.78\u0026plusmn;2.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.57\u0026plusmn;2.35\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eWhole body-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.23\u0026plusmn;0.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.94\u0026plusmn;0.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.90\u0026plusmn;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.93\u0026plusmn;0.66\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.49\u0026plusmn;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNNSA Score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e20.26\u0026plusmn;9.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e13.82\u0026plusmn;10.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e13.29\u0026plusmn;10.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e11.88\u0026plusmn;10.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.84\u0026plusmn;1.443\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e3.2 Associations between PhAs and NNSA total score\u003c/p\u003e\n\u003cp\u003eIn the Pearson correlation analysis, we observed that all segmental phase angles (PhAs) and the whole-body PhA were positively correlated with the North Star Ambulatory Assessment (NSAA) total score. Notably, the correlation coefficients of the segmental PhAs in the legs were higher compared to those of the other segments. The relationship between PhAs and the NSAA total score is summarized in Table 3. Specifically, both LL-PhA and RL-PhA demonstrated a strong and identical correlation with the NSAA total score (r = 0.753, p \u0026lt; 0.001). On the other hand, TR-PhA exhibited weaker correlations with the NSAA total score (|r| \u0026le; 0.50). For a visual representation of these correlations, refer to Figure 1, which presents the scatter plot of the PhAs.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable.3\u0026nbsp;Correlation coefficient between PhAs and NNSA total score\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" align=\"\" width=\"570\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"61.228070175438596%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eNNSA Score\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003er\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003eLA-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e0.536\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003eRA-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e0.549\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003eLL-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e0.753\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003eRL-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e0.753\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003eTR-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e0.360\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"38.771929824561404%\" valign=\"top\"\u003e\n \u003cp\u003eWhole body-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"27.894736842105264%\" valign=\"top\"\u003e\n \u003cp\u003e0.714\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"33.333333333333336%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e3.3 Comparison of phase Angle results between the two groups and its prediction of lower limb motor function loss in DMD children\u003c/p\u003e\n\u003cp\u003eWe divided the DMD children into two groups based on their motor function: group 1 (preserved ambulation function) and group 2 (loss of ambulation function). Significant differences were observed in age, North Star Ambulatory Assessment (NSAA) scores, and segmental phase angles between the two groups.\u0026nbsp;To further assess the potential of phase angles (PhAs) in predicting lower limb motor function loss in DMD children, we performed receiver operating characteristic (ROC) curve analysis. Figure 4 displays the ROC curves for predicting lower limb motor function loss using PhA values. The corresponding area under the curve (AUC) values for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA were 0.726, 0.725, 0.832, 0.863, 0.813, and 0.704, respectively(Table 5). Based on the ROC curve analysis, we identified optimal cutoff points for each segmental PhA to predict lower limb motor function loss. The cutoff points were determined as follows: 2.95\u0026deg; for RA-PhA, 2.55\u0026deg; for LA-PhA, 2.55\u0026deg; for RL-PhA, 2.65\u0026deg; for LL-PhA, 2.85\u0026deg; for whole-PhA, and 4.25\u0026deg; for TR-PhA. We also performed the ROC curve\u0026nbsp;of combination of PhA and age.The combined prediction ROC curve results are presented in the figure4(b). The areas under the ROC curves for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA, when combined with age to predict the loss of lower limb motor function, were determined to be 0.933, 0.929, 0.944, 0.951, 0.943, and 0.932, respectively. These results indicate that all the indexes possess high predictive values for the loss of lower limb motor function in DMD patients (all P\u0026lt;0.001). Notably, the combined prediction value of LL-PhA and age demonstrated the highest predictive capability.\u0026nbsp;The result show that the combination of PhA and age compared to PhAs alone provide more accurate predictive value.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"4\"\u003e\n \u003cp\u003eTable 4.Comparison of phase Angle results between the two groups\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003eGroup 1（ N=342)\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003eGroup 2（ N=57）\u003cbr\u003e\u003c/td\u003e\n \u003ctd\u003e\u003cem\u003eP\u003c/em\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eAge(yr)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e7.00（5.00，9.00）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e12.00（10.50,14.00）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eNNSA score\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e19.00（12.00，25.00）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.00（0.00，1.00）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLA-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.90(2.60,3.30)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.50(2.10,2.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.00(2.60,3.40)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.50(2.20,2.85)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.20\u0026plusmn;0.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.20(1.70,2.50)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eRL-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.24\u0026plusmn;0.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.10(1.80,2.60)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eTR-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e5.30(4.50,6.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e4.00(3.25,5.20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eWhole-PhA（\u0026deg;）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e3.10(2.70,3.55)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e2.50（2.10，2.70）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"595\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"100%\" colspan=\"8\"\u003e\n \u003cp\u003eTable.5 ROC curve utilized to evaluate the PhAs for the lower limb motor function loss.\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003eCut-off\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eAUC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"22.689075630252102%\" colspan=\"2\"\u003e\n \u003cp\u003e95%CI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003esensitivity %\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003especificity %\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eLA-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e2.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003e0.725\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e0.645\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.092436974789916%\"\u003e\n \u003cp\u003e0.804\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003e59.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003e62.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eRA-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e2.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003e0.726\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e0.654\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.092436974789916%\"\u003e\n \u003cp\u003e0.797\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003e50.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eLL-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e2.65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003e0.863\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e0.812\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.092436974789916%\"\u003e\n \u003cp\u003e0.915\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003e84.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003e76.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eRL-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e2.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003e0.832\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e0.772\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.092436974789916%\"\u003e\n \u003cp\u003e0.892\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003e73.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003e80.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eTR-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e4.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003e0.704\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e0.613\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.092436974789916%\"\u003e\n \u003cp\u003e0.794\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003e59.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003e80.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003eWB-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e2.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.268907563025211%\"\u003e\n \u003cp\u003e0.813\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.596638655462185%\"\u003e\n \u003cp\u003e0.752\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.092436974789916%\"\u003e\n \u003cp\u003e0.875\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.621848739495798%\"\u003e\n \u003cp\u003e84.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.789915966386555%\"\u003e\n \u003cp\u003e68.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.764705882352942%\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eDuchenne muscular dystrophy (DMD) is a prevalent X-linked recessive muscle degeneration disorder characterized by progressive loss of functional muscle mass over time\u003csup\u003e[6-8]\u003c/sup\u003e. The disease follows a natural history that includes a gradual decline in muscle function, leading to the loss of independent ambulation in teenage years and eventual dependence on assistance for mobility and daily activities.\u003cbr\u003e Bioelectrical impedance analysis (BIA) is based on the principle of treating the human body as a conductive cylinder. It utilizes the electrical properties of intracellular and extracellular fluids, as well as cell membranes, to measure resistance (R) and capacitive reactance (Xc) at different electrical frequencies. These measurements are then used to estimate body composition and changes through empirical regression equations. Phase Angle (PhA) reflects the health status of cells by assessing the integrity of cell membranes and the conductive properties of fluids, providing insights into tissue and organ function. PhA is considered a comprehensive indicator of nutrition, inflammation, and immunity in assessing disease severity and patient prognosis\u003csup\u003e[9,10]\u003c/sup\u003e. Previous studies have demonstrated a positive association between PhA and muscle strength\u003csup\u003e[11,12]\u003c/sup\u003e, leading to its wide discussion and application in sarcopenia. High PhA has been correlated with better muscle function in sarcopenia patients\u003csup\u003e\u0026nbsp;[13]\u003c/sup\u003e. Conversely, lower PhA has been associated with increased disease severity, decreased quadriceps strength in knee and hip osteoarthritis patients\u003csup\u003e[14,15]\u003c/sup\u003e, and reduced quadriceps strength and walking speed in older adults\u003csup\u003e[8]\u003c/sup\u003e. In the context of DMD, a study by Karina M evaluated anthropometric and bioimpedance parameters in 43 individuals with DMD, revealing lower PhA values compared to reference values in DMD boys. However, the use of PhA for assessing motor function in children with DMD is rarely described. In clinical practice and scientific research, the North Star Ambulatory Assessment (NSAA) is commonly employed to specifically measure ambulatory performance in children with DMD \u003csup\u003e[16-18]\u003c/sup\u003e. This research studies the relationship between them.\u003c/p\u003e\n\u003cp\u003eOur findings demonstrate a consistent trend between the NNSA score and PhAs, indicating a correlation between motor function and PhA in DMD. The Pearson correlation analysis revealed that all segmental PhAs and the whole-PhA were positively associated with the NNSA total score. Notably, the correlation coefficient of segmental PhAs in the legs was higher compared to other segments. A Brazilian study investigating changes in PhA across different age groups (1-80 years) demonstrated an age-dependent pattern, with PhA increasing during childhood, stabilizing during most of adulthood, and decreasing in late adulthood \u003csup\u003e[19]\u003c/sup\u003e. In our study, we observed that PhAs reached their peak around five to six years of age and subsequently declined. This trend is significantly different from that observed in the normal population. Additionally, we found that the NSAA total score gradually declined over time after six to seven years old, consistent with previous reports in the literature \u003csup\u003e[20,21]\u003c/sup\u003e. In the typical course of DMD, patients begin to exhibit abnormal gait at around three years of age. Initially, motor development continues, but they gradually encounter difficulties in climbing, running, jumping, and standing up. Signs such as Gower sign, lordosis, and bilateral gastrocnemius pseudohypertrophy may become evident. After the plateau period between five and seven years old, motor abilities begin to regress. In our study, we observed that PhAs decline at 5-6 years old, earlier than the change observed in the NNSA score at 6-7 years old. This suggests that PhA may reflect changes in muscle cell function earlier than changes in motor function, indicating its potential as a predictor of clinical motor function.\u003c/p\u003e\n\u003cp\u003eFurthermore, we found that the loss of lower limb motor function was closely related to the WB-PhA and the segmental PhAs. ROC curve analysis demonstrated that PhAs have predictive ability for the loss of lower limb function in children with DMD. The areas under the ROC curves for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA predict the loss of lower limb motor function were 0.726, 0.725, 0.832, 0.863, 0.813, and 0.704, respectively. This indicates that PhAs, particularly the PhA in legs, can serve as indicators to evaluate the loss of lower limb motor function in children with DMD and even as markers to assess the degree of lower limb muscle injury.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe further analyzed the ROC curve of PhA combined with age, which revealed that both PhAs and PhAs combined with age had predictive ability for the loss of lower limb function in DMD children. The areas under the ROC curves for RA-PhA, LA-PhA, RL-PhA, LL-PhA, whole-PhA, and TR-PhA combined with age to predict the loss of lower limb motor function were 0.933, 0.929, 0.944, 0.951, 0.943, and 0.932, respectively. These results indicate that all the indexes possess high predictive values for the loss of lower limb motor function in DMD patients (all P\u0026lt;0.001).\u0026nbsp;PhA in legs combined with age exhibited the highest predictive values for the loss of lower limb motor function in DMD patients. The combination of PhA and age compared to PhAs alone provide more accurate predictive value.\u003c/p\u003e\n\u003cp\u003eIt is also important to acknowledge several limitations of our study. First, we did not have data on muscle strength, other motor parameters, and muscle pathology, which could have provided further insights into the relationship between PhAs and motor function in DMD children. Second, our study design was cross-sectional, meaning that we could not establish causal relationships between PhAs and motor function. Future research should include larger cohorts and prospective studies to explore these relationships in more depth. Third, our sample size for participants aged 12 years and older was insufficient to analyze the trend of phase Angle in older children. In future studies, it would be valuable to investigate the correlation between PhA and muscle pathological changes, muscle strength, and other motor function parameters.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIn conclusion, our findings suggest that PhAs are associated with motor function in DMD children, and PhAs, especially when combined with age, have predictive ability for the loss of lower limb function. PhA could potentially serve as a simple, fast, and non-invasive marker to predict the loss of lower limb motor function in children with DMD.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eBMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ebody mass index\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eICW\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eintracellular water\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eECW\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eextracellular water\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSMM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eskeletal muscle mass\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eFFM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003efat-free mass\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eBFM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ebody fat mass\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ePBF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003epercentage of body fat\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eVFA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003evisceral fat area\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eSMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eskeletal muscle index\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eBCM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ebody cell mass\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eBMR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eBasal metabolic rate\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLA-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eleft arm phase angle\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eRA -PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eright arm phase angle\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eLL-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eleft leg phase angle\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eRL-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eright leg phase angle\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eTR-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003etrunk phase angle\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eWB-PhA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003ewhole body phase angle\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eNNSA\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eNorth Star Ambulatory Assessment\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eROC curve\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\"\u003e\n \u003cp\u003eReceiver operating characteristic curve\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate and Consent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe research protocol was reviewed and approved by the Research Ethics Committee of West China Second Hospital of Sichuan University.This retrospective study was carried out using the opt-out method for the caseseries of our hospital and was conducted in accordance with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Informed consent was waived by our Institutional Review Board because of the retrospective nature of our study. This study was approved by the Medical Ethics Committee of West China Second University Hospital (2023(091)), Sichuan University, Chengdu, China.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and analysed during the current study are available from the corresponding author on reasonable request.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eQin Hu, Xiaoyong Chen, Shaojie Luo, YanhongWang, Peicong Fan, Xiaona Wu, Hui Zhou1 Huayan Xu, Na Li, and Xiaotang Cai declare that they have no conflicts of interest.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by the Sichuan Science and Technology Support Program(2023YFG0284), the Chengdu Municipal Health Commission Project(21PJ048) and Science and Technology Department of Sichuan Province( 23ZDYF0395).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors were involved in the design of the study. Also, they participate in data collection, statistical analysis and data interpretation, write the submitted articles, and complete the final approval of the submitted version.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThanks to our team, the days we work together are happy and the days we struggle together are unforgettable. Thank you to every colleague for all the effort they put into this project.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHoffman EP, Brown RH Jr,Kunkel LM. Dystrophin: the protein product of the Duchenne muscular dystrophy locus. Cell 987;51919-928.\u003c/li\u003e\n\u003cli\u003ePetrof BJ, Shrager JB, Stedman HH， Kelly AM，Sweeney HL. Dystrophin protects the sarcolemma from stresses developed during muscule contraction. Proc NatlAcad Sci USA 1993;90: 3710-3714.\u003c/li\u003e\n\u003cli\u003eBettica P, Petrini S, D\u0026apos;Oria V, et al. Histological effects of givinostat in boys with Duchenne muscular dystrophy. Neuromuscul Disord. 2016;26(10):643-649. doi:10.1016/j.nmd.2016.07.002\u003c/li\u003e\n\u003cli\u003eAkamatsu Y, Kusakabe T, Arai H, et al. Phase angle from bioelectrical impedance analysis is a useful indicator of muscle quality. \u003cem\u003eJ Cachexia Sarcopenia Muscle\u003c/em\u003e. 2022;13(1):180-189. doi:10.1002/jcsm.12860\u003c/li\u003e\n\u003cli\u003eMatias CN, Nunes CL, Francisco S, et al. Phase angle predicts physical function in older adults. \u003cem\u003eArch Gerontol Geriatr\u003c/em\u003e. 2020;90:104151. doi:10.1016/j.archger.2020.104151\u003c/li\u003e\n\u003cli\u003eFlanigan, K. M. (2014). Duchenne and Becker muscular dystrophies. Neurologic Clinics, 32(3), 671-688.\u003c/li\u003e\n\u003cli\u003eMendell, J. R., Shilling, C., Leslie, N. D., Flanigan, K. M., Al-Dahhak, R., Gastier-Foster, J., ... \u0026amp; Connolly, A. M. (2012). Evidence-based path to newborn screening for Duchenne muscular dystrophy. Annals of Neurology, 71(3), 304-313.\u003c/li\u003e\n\u003cli\u003eHoffman, E. P., \u0026amp; McNally, E. M. (2019). Duchenne muscular dystrophy: A genetic and molecular update for the clinician. Pediatric Clinics, 66(3), 563-579.\u003c/li\u003e\n\u003cli\u003eKyle UG, Bosaeus I, De Lorenzo AD, et al. Bioelectrical impedance analysis--part I: review of principles and methods. \u003cem\u003eClin Nutr\u003c/em\u003e. 2004;23(5):1226-1243. doi:10.1016/j.clnu.2004.06.004\u003c/li\u003e\n\u003cli\u003eWang W, Liang S, Zhu F, et al. Association of the malnutrition-inflammation score with anthropometry and body composition mesure ments in patients with chronic kidney disease[J]. Ann Palliat Med,2019,8(5):596-603.\u003c/li\u003e\n\u003cli\u003eSelberg, O., \u0026amp; Selberg, D. (2002). Norms and correlates of bioimpedance phase angle in healthy human subjects, hospitalized patients, and patients with liver cirrhosis. European Journal of Applied Physiology, 509\u0026ndash;516.\u003c/li\u003e\n\u003cli\u003eMatias CN, Campa F, Nunes CL, et al. Phase Angle Is a Marker of Muscle Quantity and Strength in Overweight/Obese Former Athletes. \u003cem\u003eInt J Environ Res Public Health\u003c/em\u003e. 2021;18(12):6649. Published 2021 Jun 21. doi:10.3390/ijerph18126649\u003c/li\u003e\n\u003cli\u003eCRUZ JENTOFT AJ, BAEYENS JP, BAUER JM, et al. Sarcopenia: European consensus on definition and diagnosis: Report of the European Working Group on Sarcopenia in Older People.[J]. Age and Ageing: The Journal of the British Geriatrics Society and the British Society for Research on Ageing,2010,39(4):412-423. DOI:10.1093/ageing/afq034.\u003c/li\u003e\n\u003cli\u003eWada O, Kurita N, Yamada M, Mizuno K. Structural severity, phase angle, and quadriceps strength among patients with knee osteoarthritis: the SPSS-OK study. \u003cem\u003eClin Rheumatol\u003c/em\u003e. 2020;39(10):3049-3056. doi:10.1007/s10067-020-05056-w \u003c/li\u003e\n\u003cli\u003eGarlini LM, Alves FD, Ceretta LB, Perry IS, Souza GC, Clausell NO. Phase angle and mortality: a systematic review. \u003cem\u003eEur J Clin Nutr\u003c/em\u003e. 2019;73(4):495-508. doi:10.1038/s41430-018-0159-1\u003c/li\u003e\n\u003cli\u003eMcDonald CM, Campbell C, Torricelli RE, Finkel RS, Flanigan KM, Goemans N, et al. Ataluren in patients with nonsense mutation Duchenne muscular dystrophy (ACT DMD): a multicentre, randomised, double-blind, placebo-controlled, phase 3 trial. Lancet. 2017;390(10101):1489\u0026ndash;98. Epub 2017/07/22. pmid:28728956.\u003c/li\u003e\n\u003cli\u003eRicotti V, Ridout DA, Pane M, Main M, Mayhew A, Mercuri E, et al. The NorthStar Ambulatory Assessment in Duchenne muscular dystrophy: considerations for the design of clinical trials. J Neurol Neurosurg Psychiatry. 2016;87(2):149\u0026ndash;55. pmid:25733532; PubMed Central PMCID: PMC4752678.\u003c/li\u003e\n\u003cli\u003eMazzone ES, Pane M, Sormani MP, Scalise R, Berardinelli A, Messina S, et al. 24 month longitudinal data in ambulant boys with Duchenne muscular dystrophy. PLoS One. 2013;8(1): e52512. pmid:23326337; PubMed Central PMCID: PMC3543414.\u003c/li\u003e\n\u003cli\u003eMattiello R, Mundstock E, Ziegelmann PK. Brazilian Reference Percentiles for Bioimpedance Phase Angle of Healthy Individuals. \u003cem\u003eFront Nutr\u003c/em\u003e. 2022; 9:912840. Published 2022 Jul 6. doi:10.3389/fnut.2022.912840\u003c/li\u003e\n\u003cli\u003eMazzone E, Martinelli D, Berardinelli A, Messina S, D\u0026apos;Amico A, Vasco G, et al. North Star Ambulatory Assessment, 6-minute walk test and timed items in ambulant boys with Duchenne muscular dystrophy. Neuromuscul Disord. 2010;20(11):712\u0026ndash;6. pmid:20634072.\u003c/li\u003e\n\u003cli\u003ePane M, Mazzone ES, Sivo S, Sormani MP, Messina S, A DA, et al. Long term natural history data in ambulant boys with Duchenne muscular dystrophy: 36-month changes. PLoS One. 2014;9(10): e108205. pmid:25271887; PubMed Central PMCID: PMC4182715.\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":"Duchenne muscular dystrophy, phase angle, children, motor function","lastPublishedDoi":"10.21203/rs.3.rs-3892999/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3892999/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Duchenne muscular dystrophy (DMD) is a prevalent X-linked recessive muscle degeneration disorder that involves the gradual loss of functional muscle mass. The Phase Angle (PhA) can indicate changes in cell membrane integrity and intercellular space. It has been recognized as a valuable tool for assessing disease severity and predicting patient outcomes. However, there is limited research on the application of PhA in children with neuromuscular diseases, including DMD.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective：\u003c/strong\u003ewe investigated the relationship between Phase Angle (PhA) and motor function in children with DMD. We specifically examined the correlation between segmental PhAs and motor function and evaluated the effectiveness of segmental PhAs as a measure for assessing motor function in DMD children\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethod:\u003c/strong\u003e 399 DMD patients were divided into loss of lower limb motor function group (n = 57) and preserve lower limb motor function group (n = 342). The correlation between PhA and motor function were analyzed through spearman correlation analysis. The predictive value of PhA and PhA combining age for lower limb motor function loss was analyzed by ROC curve.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResult: \u003c/strong\u003eTR-PhA reaches its peak at 6 years old, while other PhAs reaches its peak at 5-6years old and subsequently declines over time. There was a significant correlation between PhAs and the NSAA score, with the strongest correlation observed in leg PhA (r=0.753, P\u0026lt;0.001). ROC curve was used and showed that PhAs (LA, RA, LL, RL, TR, and whole) can predict the loss of lower limb function in DMD children (AUC from 0.725 to 0.863).The corresponding cut-off PhA values were 2.55°, 2.95°, 2.65°, 2.55°, 4.25°, and 2.85°, respectively. Additionally, PhAs combined with age had more excellent predictive ability for lower limb function loss than PhAs((AUC from 0.929 to 0.951).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e The time of peak of PhAs are earlier than NNSA score (peak at 6-7years old). PhAs in legs demonstrate the strongest correlation and highest predictive value for lower limb motor function loss. PhA could serve as a simple, fast, and non-invasive marker to predict the loss of lower limb motor function in DMD children.\u003c/p\u003e","manuscriptTitle":"Correlation between segmental Phase Angles and motor function of DMD children and predictive value of Phase angels for lower limb motor function loss","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-02 17:52:39","doi":"10.21203/rs.3.rs-3892999/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":"2973c900-12fe-4c0e-9da1-7ba2a2056b08","owner":[],"postedDate":"February 2nd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-02T20:54:52+00:00","versionOfRecord":[],"versionCreatedAt":"2024-02-02 17:52:39","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3892999","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3892999","identity":"rs-3892999","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}