Evaluation of Environmental Tobacco Smoke Exposure of Pediatric Patients with Chronic Lung Diseases

Evaluation of Environmental Tobacco Smoke Exposure of Pediatric Patients with Chronic Lung Diseases | 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 Evaluation of Environmental Tobacco Smoke Exposure of Pediatric Patients with Chronic Lung Diseases Merve Setenay Akyüzlüer Güneş, Gizem Ozcan, Fazilcan Zirek, Mervenur Tekin, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7228175/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 Purpose: It is very important to minimize the environmental risks that may increase respiratory morbidity in children with chronic lung diseases (CLD). We aimed to determine environmental tobacco smoke (ETS) exposure in children with CLD. Methods: Two hundred and fifty patients with the diagnosis of CLD were included in this study. Parents of the children with CLD were asked about their smoking habits through a questionnaire. ETS exposure was also determined by the measurement of plasma cotinine level of these children, and levels ≥12 ng/ml were considered exposed to ETS. Results: Although according to parental reports 58% of patients lived in the same household with at least one smoker, 72% of patients had a plasma cotinine level of ≥12 ng/ml. Cotinine values of children who lived in the same house with at least one smoker, were exposed to ETS in the last 7 days and whose parents allowed smoking in their car were significantly higher than the opposite groups (34,76±28,16 versus 21,57±12,76; 42,58±33,61 versus 23,66±14,94; and 40,71±30,52 and 21,00±13,94 ng/ml respectively). Conclusions: This study revealed that children with CLD exhibited significantly elevated plasma cotinine levels. It emphasizes the critical need to reduce ETS exposure in CLD patients. Objective measures like plasma cotinine can provide reliable assessments of exposure, complementing parental reports which may underestimate actual exposure levels. Moving forward, efforts to mitigate ETS exposure among CLD patients should include targeted smoking cessation interventions and stricter enforcement of smoke-free policies in homes and public spaces. cotinine children environmental tobacco smoke chronic lung disease second hand tobacco smoke third hand tobacco smoke What is known? There are studies in the literature showing the rate of secondhand tobacco exposure in healthy children and children with bronchopulmonary dysplasia (BPD) and cystic fibrosis (CF) through questionnaires or objective measurements. What is new? Our study points the tobacco smoke exposure of children with CLD, which includes many different disease groups, both with the help of a questionnaire and objective measurement. Since there is a very high level of tobacco smoke exposure in CLD patients, an objective biomarker can be used in addition to questioning to determine tobacco smoke exposure in these patients. Introduction Environmental tobacco smoke (ETS) exposure is also referred to as secondhand tobacco smoke (SHS). It is known that tobacco smoke has many negative effects not only on users but also on those who are exposed to ETS (1, 2). Children are most affected by ETS, especially those with preexisting lung diseases (3). Exposure to tobacco smoke can also negatively affect children's physical development, particularly lung development (1, 4). With recent advancements in diagnosis and treatment methods, the number of patients being monitored for chronic lung diseases (CLD) during childhood has been increasing. SHS increases respiratory tract infections, and changes in conducting airway structure can lead to decreased airflow and pulmonary function (5, 6). Recovery in patients with CLD depends on adequate postnatal lung growth and avoiding lung injury, making it crucial to minimize environmental risks that may increase respiratory morbidity in this patient group (6-9). There are studies in the literature evaluating tobacco smoke exposure in children with bronchopulmonary dysplasia (BPD) and cystic fibrosis (CF) (7-10). It is important to evaluate tobacco smoke exposure in children with BPD and CF as well as in children with other CLD groups. Since the exposure of this sensitive population to tobacco smoke is as important as the exposure of the healthy population, we aimed to determine ETS exposure in children with CLD in our study. Material and Method Patients In this cross-sectional study, 250 patients diagnosed with CLD, aged between 1 month and 18 years, who were followed up in the Pediatric Pulmonology Department of our hospital between June 2019 and January 2021, were included. Informed consent was obtained from the parents of all patients, and from patients older than nine years. During this period, approximately 600 CLD patients were admitted to the department, and out of 600 patients, 250 who consented to participate were included in the study. Definition and Classification of CLD There is no exact definition of childhood CLD in pediatric pulmonary disease textbooks and reviews, and the same diseases are classified differently in various sources. For example, pulmonary hypoplasia is discussed in both lung malformations and developmental disorder sections of interstitial lung diseases. Additionally, CLD can cause respiratory problems through multiple mechanisms, such as neuromuscular diseases affecting respiratory functions via chest wall weakness and swallowing dysfunction. We grouped patients who required continuous follow-up and treatment in the Pediatric Pulmonology Department as CLD (Table 2). Measurements Patients Characteristics and Parental Questionnaire-Based Evaluation Patients’ gender, age, race, height and weight percentiles, their CLD group and respiratory support status were recorded. A pediatrician conducted face-to-face questionnaire surveys with parents of CLD patients. The parents were asked about their smoking habits, types of tobacco products they use (such as electronic cigarettes, hookahs), current smoking status, daily cigarette consumption, places where they smoke, whether they allow smoking at home and/or in the car, and whether their children were exposed to ETS in the last 7 days. Measurement of Plasma Cotinine Levels Five milliliters of venous blood from each patient were collected in EDTA tubes, centrifuged, and plasma samples stored at -80 degrees Celsius. Plasma cotinine levels were measured using the ELISA method (Bioassay Technology Laboratory, China). The analytical sensitivity was 0.019 pg/ml, with intra-assay and inter-assay coefficients of variation less than 8% and 10%, respectively. Patients with plasma cotinine levels ≥ 12 ng/ml were considered exposed to ETS (11). Statistical Analysis Data analysis was performed using SPSS 11.5. Descriptive statistics included counts (n), percentages (%), mean ± standard deviation (SD), and median (minimum-maximum) values. The Mann-Whitney U test compared quantitative variables between two categories of qualitative variables, due to non-normal distribution assumptions. The Kruskal Wallis H test evaluated differences among qualitative variable categories with more than two categories. Post hoc tests included the Mann-Whitney U test with Bonferroni correction for multiple comparisons. The Chi-square test examined relationships between qualitative variables, and Spearman correlation analyzed relationships between quantitative variables, with significance set at p < 0.05. Results Patient Characteristics The mean patient age was 5.97 ± 5.44 years (range: 1 month-18 years), with 42.4% females. All patients were Caucasian. Among the patients, 29.2% had a weight below the 3rd percentile and 27.2% had a height below the 3rd percentile. The demographic characteristics of the patients and their families are presented in Table 1. Table 2 displays the distribution of 250 CLD cases by diagnosis. Aspiration syndromes (17.6%) constituted the largest group, followed by BPD (14.8%), pectus deformities (13.2%), non-CF bronchiectasis (9.2%), CF (8%), bronchiolitis obliterans syndrome (post-infectious or hematopoietic stem cell transplantation) (6.8%), central hypoventilation syndromes (6.8%), and lung/respiratory problems due to neuromuscular diseases (5.2%). Less prevalent groups, such as childhood interstitial and diffuse lung diseases and congenital lung malformations, were grouped as "Others" (18.4%). Seventy patients (28%) required respiratory support: 32 receive nasal oxygen, 30 invasive mechanical ventilation, and 8 non-invasive mechanical ventilation. Environmental Tobacco Smoke Exposure One hundred and forty-five patients (58%) lived with at least one smoker (Table 3). All smokers were smoking cigarettes; among these families, 69 (47.6%) were smoking > 20 cigarettes/day. Detailed ETS exposure based on the parental survey is presented in Table 3 Approximately one-fourth of mothers and half of fathers were smokers. Regardless of their own smoking status, 41.7% of families allowed smoking in the car and 82% at home. Eighty-four patients (33.6%) were exposed to ETS in the past seven days, with 34.5% of those exposures occurring indoors (Table 3). ETS exposure rates by disease groups are summarized in Table 4. Plasma Cotinine Levels The mean plasma cotinine level among all 250 patients was 30.02 ± 24.59 ng/ml. When cotinine levels were compared according to variables, cotinine levels were found to be significantly higher in children living with at least one smoker, in children who were recently exposed to tobacco smoke, in children whose mothers smoke, and in children whose families allow smoking at home and in the car. Additionally, children of parents smoking > 20 cigarettes/day had higher cotinine levels compared to those whose parents smoked < 10 or 10-20 cigarettes/day. No significant differences were found in cotinine levels based on outdoor vs. indoor exposure, number of household smokers, or household type (Table 5). Environmental tobacco smoke exposure rates of disease groups based on plasma cotinine values is presented in Table 6. Plasma cotinine levels were ≥ 12 ng/ml in 181 of 250 patients (72.4%). Seventy six percent of children who are not exposed to tobacco smoke at home; 30% of those not exposed to tobacco smoke in the past week; and 29% of those living in smoke-free homes had cotinine levels ≥ 12 ng/ml. Among 105 children (76.1%) not exposed to tobacco smoke at home, 50 out of 166 children (30.1%) not exposed to tobacco smoke in the last week, and 13 out of 45 children (28.8%) living in homes where tobacco consumption is not allowed, had plasma cotinine levels ≥ 12 ng/ml. Discussion This study shows that many children with chronic lung disease have elevated plasma cotinine levels even when their parents report no exposure to tobacco smoke, highlighting the importance of using objective biomarkers to assess environmental tobacco smoke exposure accurately. In this study, 250 patients with chronic lung disease (CLD) were evaluated for exposure to environmental tobacco smoke (ETS) using a questionnaire and measurement of plasma cotinine levels. Although approximately half of the patients included in the study reported ETS exposure based on parental questionnaires, approximately 70% of the patients had cotinine levels ≥ 12 ng/ml based on plasma cotinine measurements. Maternal smoking status, presence of smokers at home, recent tobacco exposure, number of cigarettes smoked at home, and allowance of smoking at home and in vehicles significantly affected plasma cotinine levels.Global studies have shown that an estimated 40% of children were exposed to ETS in 2004 (12); this is lower than the exposure rate found in our study population (58%) but similar to the ETS exposure rate in the last week (33.6%). In another study conducted in Turkey, in which 642 healthy children aged 8-12 participated, it was determined that 74% of the children had at least one parent smoking at home. (13). Although the rate in our study was lower, the 58% exposure rate for CLD patients is alarming. Since there is no known safe threshold for ETS that does not harm the respiratory system, any exposure is likely harmful. The indoor exposure to tobacco smoke detected in our study (34.5%) is consistent with data from the USA (40.6%) (14) but higher than in England (12.7%) (15). However, it is important to note that while our study focused on children with CLD, the aforementioned studies were conducted on healthy children, and there may be differences due to cultural norms and legislative measures. For instance, the US and many European countries have implemented bans on tobacco use in public places since 2008. Although there are reports on ETS exposure in children with BPD and CF in other countries, according to our knowledge, there have been no reports specifically on Turkish children with CLD. This study is significant as it examines not only BPD and CF patients but also other CLD patients, which includes BPD and CF. In a study evaluating tobacco exposure through a questionnaire administered to the parents of 113 BPD patients, it was found that 56% of them were exposed to tobacco smoke. In the same study, 131 preterm babies without BPD were also evaluated, and it was observed that these preterm babies had a similar ETS exposure rate (53%) to BPD patients (16). We found that 62.1% of 37 BPD patients in our study lived with at least one smoker in the same house, a rate higher than in the aforementioned study. In the literature, survey-based ETS exposure rates for CF patients have been reported between 10% and 76% (9, 10, 17, 18). In our study, 70% of the 20 CF patients lived with at least one smoker in the same house. According to our results, not only BPD and CF patients but also nearly all CLD patients have very high ETS exposure rates, which is highly alarming. However, caution is needed when interpreting these results, as our study may reflect cultural norms that are not applicable to all children with chronic lung disease. It is known that people with higher cotinine levels are more likely to be affected by ETS exposure. In our study, based on plasma cotinine values, 72.4% of patients were exposed to ETS (plasma cotinine ≥12 ng/ml). In a study conducted in the USA between 2013 and 2016, which measured ETS exposure among healthy children aged 3-17 years using plasma cotinine, exposure was found to be 35.4%. In that study, plasma cotinine levels of 0.05-10 ng/ml were considered indicative of ETS exposure (19). Although our study used a higher plasma cotinine cutoff to define ETS exposure, it is concerning to find a higher exposure rate than reported in the aforementioned study, as ETS exposure can exacerbate existing lung and respiratory tract diseases in CLD patients. Another reason for the difference may be ethnic and racial differences in nicotine metabolism. Turkish people may have a slower nicotine metabolism than other nationalities. In a study comparing different ethnic groups living in the United States, Benowitz et al. suggested using ethnic-specific limit values (28). A review examining tobacco smoke exposure based on nicotine metabolites (urine or salivary cotinine) in CF patients reported exposure rates ranging from 44% to 54.8% (7). In our study, ETS exposure rates among CF patients based on plasma cotinine levels were higher (65%) compared to rates reported in the literature. We investigated variables affecting cotinine levels in children's plasma. We found that, maternal smoking status, presence of smokers at home, recent tobacco exposure, number of cigarettes smoked at home, and allowance of smoking at home and in vehicles significantly affected plasma cotinine levels. The number of smokers at home, type of home, and smoking location (indoors or outdoors) did not affect children's plasma cotinine levels. This suggests that where smoking occurs in the house, how many people smoke, or the type of household does not alter children's exposure. Although one study found that children whose parents smoke indoors have more respiratory symptoms than those whose parents smoke only outdoors (20) we found no significant difference in plasma cotinine levels between those exposed to ETS outdoors or indoors. This is important evidence suggesting that outdoor ETS exposure is as harmful as indoor exposure. Since ETS negatively affects children's physical development, particularly lung development, and adversely affects respiratory tract and lung diseases (1), preventing ETS exposure is crucial, especially for children with CLD. Additionally, using an objective biomarker for ETS rather than just a questionnaire, may be useful in demonstrating that the belief that " smoking outdoors is less harmful than smoking indoor" is incorrect. Among 105 children (76.1%) not exposed to tobacco smoke at home, 50 out of 166 children (30.1%) not exposed to tobacco smoke in the last week, and 13 out of 45 children (28.8%) living in homes where tobacco consumption is not allowed, had plasma cotinine levels ≥ 12 ng/ml. This result suggests that questionnaire-based information alone may not be reliable in determining ETS exposure; it may be more reliable to use a questionnaire supported by biomarkers. One of the reasons for the discrepancy between the survey and plasma cotinine results in our study may be that parents provided incorrect information. Many previous studies have also shown discrepancies between parental reports and cotinine measurements in body fluids (21-24). A study of 115 children correlating parental reports with children's urinary cotinine levels found detectable urinary cotinine levels in 14% of children whose parents did not smoke (25). Similarly, in a study of 310 healthy and asthmatic children, 139 had detectable urinary cotinine levels despite being reported as unexposed by parental surveys (26). The accuracy of reporting ETS exposure by parents depends on the tools and population studied. Therefore, objective assessment of ETS exposure is crucial because the prevalence of ETS exposure is likely underestimated by survey results. Furthermore, most parental surveys cannot accurately distinguish between unexposed children and those mildly exposed to ETS. These findings underscore the need for increased awareness of ETS exposure risks and the implementation of comprehensive tobacco control strategies that go beyond eliminating active smoking to prevent chronic ETS exposure, particularly in pediatric CLD populations. One of the main strengths of this study is its relatively large and heterogeneous sample of pediatric patients with CLD, covering a broad range of diagnoses beyond only BPD and CF. The use of both parental questionnaires and an objective biomarker (plasma cotinine) enhances the reliability of ETS exposure assessment. Moreover, it is one of the few studies in the Turkish pediatric population to investigate ETS exposure using biochemical validation. However, the study also has certain limitations. First, the possibility of including adolescent participants who may have been active smokers, despite self-reporting as non-smokers, cannot be excluded. Accurately assessing exposure to active and passive smoking is essential, particularly for children (27). In adolescents, active smoking is also a significant health issue. Second, the heterogeneity of the study group limits disease-specific interpretations. Finally, the absence of a nationally validated plasma cotinine cutoff value for ETS exposure in Turkish children may affect the generalizability of the biochemical classification. Future studies could examine each disease group separately to reveal more specific results. Furthermore, large-scale population studies could be conducted to determine the cotinine cutoff value for Turkish children. Conclusion In conclusion, the rate of exposure to ETS was high in our study among patients with CLD. Parents of these patients should be questioned about their smoking status, reminded of the dangers of ETS exposure to their children and encouraged to quit smoking. Measurement of plasma cotinine could be routinely used for objective data screening for tobacco smoke exposure in this vulnerable population. However, since there is no generally accepted plasma cotinine level to detect ETS exposure in Turkish children, further studies are necessary to determine a cutoff value specific to this population. Abbreviations BPD: Bronchopulmonary dysplasia CF: Cystic fibrosis CLD: Chronic lung diseases ETS: Environmental tobacco smoke SHS: Secondhand tobacco smoke Statements and Declarations Funding This work was supported by Ankara University Scientific Research Projects (Project Number: 20L0230009). Competing Interests The authors have no relevant financial or non-financial interests to disclose. Author Contributions Material preparation, data collection, analysis and writing were performed by Merve Setenay Akyüzlüer Güneş. Data collection, study design were performed by Fazılcan Zirek, Gizem Özcan, Mervenur Tekin. Analysis of the samples was performed by Filiz Bakar Ateş, Erva Özkan. Study conception, design and writing were performed by Nazan Çobanoğlu. The first draft of the manuscript was written by Merve Setenay Akyüzlüer Güneş and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Ethical Approval: This study was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval was obtained from the Clinical Research Ethics Committee of Ankara University (Decision No: 10-793-19, May 27, 2019). Consent to participate Informed consent was obtained from all individual participants included in the study. References Health UDo, Services H. The health consequences of smoking—50 years of progress: a report of the Surgeon General. Atlanta, GA: US Department of Health and Human Services, Centers for Disease …; 2014. Brook I, Gober AE. Recovery of potential pathogens in the nasopharynx of healthy and otitis media—prone children and their smoking and nonsmoking parents. Annals of Otology, Rhinology & Laryngology. 2008;117(10):727-30. Strachan DP, Cook DG. Health effects of passive smoking. 1. Parental smoking and lower respiratory illness in infancy and early childhood. Thorax. 1997;52(10):905. Stocks J, Dezateux C. The effect of parental smoking on lung function and development during infancy. Respirology. 2003;8(3):266-85. Wongtrakool C, Wang N, Hyde DM, Roman J, Spindel ER. Prenatal nicotine exposure alters lung function and airway geometry through α7 nicotinic receptors. American journal of respiratory cell and molecular biology. 2012;46(5):695-702. Cheraghi M, Salvi S. Environmental tobacco smoke (ETS) and respiratory health in children. European journal of pediatrics. 2009;168(8):897-905. Kopp BT, Ortega-García JA, Sadreameli SC, Wellmerling J, Cormet-Boyaka E, Thompson R, et al. The impact of secondhand smoke exposure on children with cystic fibrosis: a review. International journal of environmental research and public health. 2016;13(10):1003. Collaco JM, Aherrera AD, Breysse PN, Winickoff JP, Klein JD, McGrath-Morrow SA. Hair nicotine levels in children with bronchopulmonary dysplasia. Pediatrics. 2015;135(3):e678-e86. Sanders DB, Emerson J, Ren CL, Schechter MS, Gibson RL, Morgan W, et al. Early childhood risk factors for decreased FEV1 at age six to seven years in young children with cystic fibrosis. Annals of the American Thoracic Society. 2015;12(8):1170-6. Verma A, Clough D, McKenna D, Dodd M, Webb AK. Smoking and cystic fibrosis. Journal of the Royal Society of Medicine. 2001;94(40_suppl):29-34. Avila-Tang E, Al-Delaimy WK, Ashley DL, Benowitz N, Bernert JT, Kim S, et al. Assessing secondhand smoke using biological markers. Tobacco control. 2013;22(3):164-71. Oberg M, Jaakkola M, Woodward A, Peruga A, Prüss-Ustün A. Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries [published online ahead of print November 26, 2010]. Lancet.61388-8. Karakoç F, Dağlı E, Kut A, Pamukçu A. Çocuklarda pasif sigaraya maruziyetin serum kotinin düzeyi ile değerlendirilmesi. Türkiye Klinikleri J Pediatr. 1998;7(2):77-82. Homa DM, Neff LJ, King BA, Caraballo RS, Bunnell RE, Babb SD, et al. Vital signs: disparities in nonsmokers’ exposure to secondhand smoke—United States, 1999–2012. MMWR Morbidity and mortality weekly report. 2015;64(4):103. Jarvis MJ, Feyerabend C. Recent trends in children's exposure to second‐hand smoke in England: cotinine evidence from the Health Survey for England. Addiction. 2015;110(9):1484-92. Martinez S, Garcia-Meric P, Millet V, Aymeric-Ponsonnet M, Alagha K, Dubus J-C. Tobacco smoke in infants with bronchopulmonary dysplasia. European journal of pediatrics. 2015;174(7):943-8. Kopp BT, Sarzynski L, Khalfoun S, Hayes Jr D, Thompson R, Nicholson L, et al. Detrimental effects of secondhand smoke exposure on infants with cystic fibrosis. Pediatric Pulmonology. 2015;50(1):25-34. Ren CL, Rosenfeld M, Mayer OH, Davis SD, Kloster M, Castile RG, et al. Analysis of the associations between lung function and clinical features in preschool children with cystic fibrosis. Pediatric pulmonology. 2012;47(6):574-81. Brody DJ, Lu Z, Tsai J. Secondhand smoke exposure among nonsmoking youth: United States, 2013–2016. 2019. Johansson A, Halling A, Hermansson G. Indoor and outdoor smoking: Impact on children's health. The European Journal of Public Health. 2003;13(1):61-6. Clark S, Warner J, Dean T. Passive smoking amongst asthmatic children. Questionnaire or objective assessment? Clinical & Experimental Allergy. 1994;24(3):276-80. Derauf C, Katz AR, Easa D. Agreement between maternal self-reported ethanol intake and tobacco use during pregnancy and meconium assays for fatty acid ethyl esters and cotinine. American Journal of Epidemiology. 2003;158(7):705-9. Gunay F, Cullas Ilarslan NE, Bakar‐Ates F, Deniz K, Kadioglu YK, Kiran S, et al. Evaluation of hair cotinine and toxic metal levels in children who were exposed to tobacco smoke. Pediatric pulmonology. 2020;55(4):1012-9. Nafstad P, Botten G, HAGEN JA, ZAHLSEN K, Nilsen OG, Silsand T, et al. Comparison of three methods for estimating environmental tobacco smoke exposure among children aged between 12 and 36 months. International Journal of Epidemiology. 1995;24(1):88-94. Jurado D, Muñoz C, Luna JDD, Fernández-Crehuet M. Environmental tobacco smoke exposure in children: parental perception of smokiness at home and other factors associated with urinary cotinine in preschool children. Journal of exposure science & environmental epidemiology. 2004;14(4):330-6. Callais F, Momas I, Roche D, Gauvin S, Reungoat P, Zmirou D. Questionnaire or objective assessment for studying exposure to tobacco smoke among asthmatic and healthy children: The French VESTA Study. Preventive medicine. 2003;36(1):108-13. Florescu A, Ferrence R, Einarson T, Selby P, Soldin O, Koren G. Methods for quantification of exposure to cigarette smoking and environmental tobacco smoke: focus on developmental toxicology. Therapeutic drug monitoring. 2009;31(1):14. Benowitz NL, Bernert JT, Caraballo RS, Holiday DB, Wang J. Optimal serum cotinine levels for distinguishing cigarette smokers and nonsmokers within different racial/ethnic groups in the United States between 1999 and 2004. American journal of epidemiology. 2009;169(2):236-48. Tables Table 1. Demographic characteristics of the patients and their parents Age (years) Mean±SD 5,97±5,44 Median (Min.-Max.) 4,00 (0,08-18,00) Gender, n (%) Female 106 (42.4) Male 144 (57.6) Body Weight, n (%) <3p 73 (29.2) ≥3p 177 (70.8) Height, n (%) <3p 68 (27.2) ≥3p 182 (72.8) Birth Week, n (%) <37 week 86 (34.4) ≥37 week 164 (65.6) Birth Weight, n (%) 4000 gram 9 (3.6) Mother's Educational Status, n (%) Illiterate 17 (6.8) Primary education 178 (71.2) Undergraduate and higher 55 (22) Father's Educational Status, n (%) Illiterate 2 (0.8) Primary education 175 (70) Undergraduate and higher 73 (29.2) Income, n (%) Minimum wage and lower 80 (32.8) More than minimum wage 170 (67.2) Types of house, n (%) Private 31 (12.4) Apartment 219 (87.6) Table 2. Diseases in the study group Disease Number of Patients (n) % Aspiration Syndromes 44 17.6 BPD 37 14.8 Pectus Deformities 33 13.2 Non-CF Bronchiectasis 23 9.2 CF 20 8 Bronchiolitis Obliterans 17 6.8 Central Hypoventilation Syndromes 17 6.8 Lung and Respiratory Problems Due to Neuromuscular Diseases 13 5.2 Others 46 18.4 - Childhood Interstitial and Diffuse Lung Diseases 10 4 -Tracheobronchomalacia 8 3.2 -Congenital Lung Malformations 7 2.8 -Diaphragmatic Hernia 5 2 -Obstructive Sleep Apnea Syndrome 5 2 -Subglottic Stenosis 3 1.2 -Alpha-1 Antitrypsin Deficiency 3 1.2 -Diaphragmatic eventration 2 0.8 -Hepatopulmonary syndrome 2 0.8 -Plastic Bronchitis 1 0.4 Total 250 100 Table 3. Environmental tobacco smoke exposure information of patients based on survey Are there any tobacco consumers living in the same house?; n(%) No 105 (42.0) Yes 145 (58.0) Smoker mother; n(%) No 188 (75.2) Yes 62 (24.8) Smoker father; n(%) No 141 (56.4) Yes 109 (43.6) Tobacco consumption allowed in the car; n(%) No 112 (58.3) Yes 80 (41.7) Do not have a car 58 Tobacco consumption allowed in the house; n(%) No 45 (18.0) Yes 205 (82.0) In which areas of the house is tobacco consumption allowed?; n(%) Indoors 32 (15.6) Outdoors 173 (84.4) Has the child been exposed to tobacco smoke in the last seven days?; n(%) No 166 (66.4) Yes 84 (33.6) Where the child has been exposed to tobacco smoke in the last seven days?; n(%) Indoors 29 (34.5) Outdoors 55 (65.5) Amount of Cigarettes Smoked Daily; n (%) Less than 10 38 (26.2) 10-20 38 (26.2) More than 20 69 (47.6) Table 4. Environmental tobacco smoke exposure rates of disease groups based on survey. BPD: Bronchopulmonary dysplasia, CF: Cystic fibrosis, HSCT: Hematopoetic stem cell transplantation. Disease Groups (n) Disease Groups (%) Patients living in the same house with at least one smoker , n(%) Tobacco consumption allowed in the car, n(%) Tobacco consumption allowed in the house, n(%) Patients has been exposed to tobacco smoke in the last seven days, n(%) Aspiration Syndromes (44) 17.6 30(68.1) 16(36) 37(84) 11(25) BPD (37) 14.8 23(62.1) 10(27) 25(67.5) 8(21.6) Pectus Deformities (33) 13.2 16(48.4) 8(24.2) 30(90.9) 14(42.4) Non-CF Bronchiectasis (23) 9.2 14(60.8) 7(30.4) 18(78.2) 9(39.1) CF (20) 8 14(70) 7(35) 16(80) 8(40) Bronchiolitis Obliterans Syndrome (post-infectious or post HSCT) (17) 6.8 8(47) 4(23.5) 14(82.3) 4(23.5) Central Hypoventilation Syndromes (17) 6.8 8(47) 3(17.6) 13(76.4) 4(23.5) Lung and Respiratory Problems Due to Neuromuscular Diseases (13) 5.2 2(15.3) 3(23) 8(61.5) 1(7.6) Others (46) - Childhood Interstitial and Diffuse Lung Diseases -Tracheobronchomalacia -Congenital Lung Malformations -Diaphragmatic Hernia -Obstructive Sleep Apnea Syndrome -Subglottic Stenosis -Alpha-1 Antitrypsin Deficiency -Diaphragmatic eventration -Hepatopulmonary syndrome -Plastic Bronchitis 18.4 31(67.3) 10(21.7) 38(82.6) 10(21.7) Table 5. Comparison of patients' cotinine levels according to the variables Variables Cotinine (ng/ml) Mean.±SD p value Gender Female 29,43±26,12 0,267 a Male 30,45±23,49 Body weight <3p 28,42±25,56 0,183 a ≥3p 30,68±24,22 Height <3p 29,40±25,76 0,480 a ≥3p 30,24±24,21 Living in the same house with at least one smoker No 21,57±12,76 0,005 a Yes 34,76±28,16 Tobacco smoke exposure in the last week No 23,66±14,94 <0,001 a Yes 42,58±33,61 Maternal Tobacco Consumption No 25,48±17,53 0,007 a Yes 43,76±35,65 Paternal Tobacco Consumption No 31,61±26,29 0,301 a Yes 27,96±22,15 Smoking Allowed in the Car No 21,00±13,94 <0,001 a Yes 40,71±30,52 Smoking Allowed at Home No 20,42±11,80 0,031 a Yes 32,12±26,14 Amount of Cigarettes Smoked Daily Less than 10 20,63±13,86 0,005 b 10-20 24,91±18,44 More than 20 38,82±30,15 Type of House Private 26,84±24,64 0,257 a Apartment 30,46±24,61 Respiratory Support No 29,14±23,09 0,862 b Yes 32,26±28,13 Respiratory Support Type Invasive mechanical ventilation 20,57±14,20 0,094 b Non-invasive mechanical ventilation 21,26±32,29 Nasal Oxygen 32,28±28,43 Locations Exposed to Tobacco Smoke in the Last Seven Days Outdoors 31,24±31,60 0,420 a Indoors 33,46±26,44 Number of People Using Tobacco in the Same House 1 31,43±24,89 0,184 a ≥2 28,40±25,83 Areas Where Tobacco Use Is Allowed at Home Indoors 27,84±22,73 0,540 a Outdoors 31,51±25,83 a:Mann-Whitney U test, b:Kruskal Wallis H test, SD: Standard deviation, Min: Minimum, Max: Maximum, p: Percentile Table 6. Environmental tobacco smoke exposure rates of disease groups based on plasma cotinine values. BPD: Bronchopulmonary dysplasia, CF: Cystic fibrosis, HSCT: Hematopoetic stem cell transplantation. Disease Groups (n) Plasma cotinine ≥ 12 ng/ml n(%) Non-CF Bronchiectasis (23) 20(86.9) Bronchiolitis Obliterans Syndrome (post-infectious or post HSCT) (17) 14(82.3) BPD (37) 30(81) Pectus Deformities (33) 25(75.7) Aspiration Syndromes (44) 31(70.4) Others (46) 30(65.2) CF (20) 13(65) Central Hypoventilation Syndromes (17) 11(64.7) Lung and Respiratory Problems Due to Neuromuscular Diseases (13) 8(61.5) 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. 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Since there is a very high level of tobacco smoke exposure in CLD patients, an objective biomarker can be used in addition to questioning to determine tobacco smoke exposure in these patients.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eEnvironmental tobacco smoke (ETS) exposure is also referred to as secondhand tobacco smoke (SHS). It is known that tobacco smoke has many negative effects not only on users but also on those who are exposed to ETS\u0026nbsp;(1, 2).\u0026nbsp;Children are most affected by ETS, especially those with preexisting lung diseases\u0026nbsp;(3).\u0026nbsp;Exposure to tobacco smoke can also negatively affect children's physical development, particularly lung development\u0026nbsp;(1, 4).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWith recent advancements in diagnosis and treatment methods, the number of patients being monitored for chronic lung diseases (CLD) during childhood has been increasing. SHS increases respiratory tract infections, and changes in conducting airway structure can lead to decreased airflow and pulmonary function (5, 6). Recovery in patients with CLD depends on adequate postnatal lung growth and avoiding lung injury, making it crucial to minimize environmental risks that may increase respiratory morbidity in this patient group\u0026nbsp;(6-9).\u003c/p\u003e\n\u003cp\u003eThere are studies in the literature evaluating tobacco smoke exposure in children with bronchopulmonary dysplasia (BPD) and cystic fibrosis (CF) (7-10). It is important to evaluate tobacco smoke exposure in children with BPD and CF as well as in children with other CLD groups. Since the exposure of this sensitive population to tobacco smoke is as important as the exposure of the healthy population, we aimed to determine ETS exposure in children with CLD in our study.\u003c/p\u003e"},{"header":"Material and Method ","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003ePatients\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn this cross-sectional study, 250 patients diagnosed with CLD, aged between 1 month and 18 years, who were followed up in the Pediatric Pulmonology Department of our hospital between June 2019 and January 2021, were included. Informed consent was obtained from the parents of all patients, and from patients older than nine years. During this period, approximately 600 CLD patients were admitted to the department, and out of 600 patients, 250 who consented to participate were included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eDefinition and Classification of CLD\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThere is no exact definition of childhood CLD in pediatric pulmonary disease textbooks and reviews, and the same diseases are classified differently in various sources. For example, pulmonary hypoplasia is discussed in both lung malformations and developmental disorder sections of interstitial lung diseases. Additionally, CLD can cause respiratory problems through multiple mechanisms, such as neuromuscular diseases affecting respiratory functions via chest wall weakness and swallowing dysfunction. We grouped patients who required continuous follow-up and treatment in the Pediatric Pulmonology Department as CLD (Table 2).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eMeasurements\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cu\u003ePatients Characteristics and Parental Questionnaire-Based Evaluation\u003c/u\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePatients’ gender, age, race, height and weight percentiles, their CLD group and respiratory support status were recorded. A pediatrician conducted face-to-face questionnaire surveys with parents of CLD patients. The parents were asked about their smoking habits, types of tobacco products they use (such as electronic cigarettes, hookahs), current smoking status, daily cigarette consumption, places where they smoke, whether they allow smoking at home and/or in the car, and whether their children were exposed to ETS in the last 7 days.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cu\u003eMeasurement of Plasma Cotinine Levels\u003c/u\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFive milliliters of venous blood from each patient were collected in EDTA tubes, centrifuged, and plasma samples stored at -80 degrees Celsius. Plasma cotinine levels were measured using the ELISA method (Bioassay Technology Laboratory, China). The analytical sensitivity was 0.019 pg/ml, with intra-assay and inter-assay coefficients of variation less than 8% and 10%, respectively. Patients with plasma cotinine levels ≥ 12 ng/ml were considered exposed to ETS\u0026nbsp;(11).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eStatistical Analysis\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData analysis was performed using SPSS 11.5. Descriptive statistics included counts (n), percentages (%), mean ± standard deviation (SD), and median (minimum-maximum) values. The Mann-Whitney U test compared quantitative variables between two categories of qualitative variables, due to non-normal distribution assumptions. The Kruskal Wallis H test evaluated differences among qualitative variable categories with more than two categories. Post hoc tests included the Mann-Whitney U test with Bonferroni correction for multiple comparisons. The Chi-square test examined relationships between qualitative variables, and Spearman correlation analyzed relationships between quantitative variables, with significance set at p \u0026lt; 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003ePatient Characteristics\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mean patient age was 5.97 ± 5.44 years (range: 1 month-18 years), with 42.4% females. All patients were Caucasian. Among the patients, 29.2% had a weight below the 3rd percentile and 27.2% had a height below the 3rd percentile. The demographic characteristics of the patients and their families are presented in Table 1. Table 2 displays the distribution of 250 CLD cases by diagnosis. Aspiration syndromes (17.6%) constituted the largest group, followed by BPD (14.8%), pectus deformities (13.2%), non-CF bronchiectasis (9.2%), CF (8%), bronchiolitis obliterans syndrome (post-infectious or hematopoietic stem cell transplantation) (6.8%), central hypoventilation syndromes (6.8%), and lung/respiratory problems due to neuromuscular diseases (5.2%). Less prevalent groups, such as childhood interstitial and diffuse lung diseases and congenital lung malformations, were grouped as \"Others\" (18.4%). Seventy patients (28%) required respiratory support: 32 receive nasal oxygen, 30 invasive mechanical ventilation, and 8 non-invasive mechanical ventilation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003eEnvironmental Tobacco Smoke Exposure\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOne hundred and forty-five patients (58%) lived with at least one smoker (Table 3). All smokers were smoking cigarettes; among these families, 69 (47.6%) were smoking \u0026gt; 20 cigarettes/day. Detailed ETS exposure based on the parental survey is presented in Table 3 Approximately one-fourth of mothers and half of fathers were smokers. Regardless of their own smoking status, 41.7% of families allowed smoking in the car and 82% at home. Eighty-four patients (33.6%) were exposed to ETS in the past seven days, with 34.5% of those exposures occurring indoors (Table 3). ETS exposure rates by disease groups are summarized in Table 4.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003e\u003cu\u003ePlasma Cotinine Levels\u003c/u\u003e\u003c/em\u003e\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe mean plasma cotinine level among all 250 patients was 30.02 ± 24.59 ng/ml. When cotinine levels were compared according to variables, cotinine levels were found to be significantly higher in children living with at least one smoker, in children who were recently exposed to tobacco smoke, in children whose mothers smoke, and in children whose families allow smoking at home and in the car. Additionally, children of parents smoking \u0026gt; 20 cigarettes/day had higher cotinine levels compared to those whose parents smoked \u0026lt; 10 or 10-20 cigarettes/day. No significant differences were found in cotinine levels based on outdoor vs. indoor exposure, number of household smokers, or household type (Table 5). Environmental tobacco smoke exposure rates of disease groups based on plasma cotinine values is presented in Table 6.\u003c/p\u003e\n\u003cp\u003ePlasma cotinine levels were ≥ 12 ng/ml in 181 of 250 patients (72.4%). Seventy six percent of children who are not exposed to tobacco smoke at home; 30% of those not exposed to tobacco smoke in the past week; and 29% of those living in smoke-free homes had cotinine levels ≥ 12 ng/ml. Among 105 children (76.1%) not exposed to tobacco smoke at home, 50 out of 166 children (30.1%) not exposed to tobacco smoke in the last week, and 13 out of 45 children (28.8%) living in homes where tobacco consumption is not allowed, had plasma cotinine levels ≥ 12 ng/ml.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study shows that many children with chronic lung disease have elevated plasma cotinine levels even when their parents report no exposure to tobacco smoke, highlighting the importance of using objective biomarkers to assess environmental tobacco smoke exposure accurately.\u003c/p\u003e\n\u003cp\u003eIn this study, 250 patients with chronic lung disease (CLD) were evaluated for exposure to environmental tobacco smoke (ETS) using a questionnaire and measurement of plasma cotinine levels. Although approximately half of the patients included in the study reported ETS exposure based on parental questionnaires, approximately 70% of the patients had cotinine levels ≥ 12 ng/ml \u0026nbsp;based on plasma cotinine measurements. \u0026nbsp;Maternal smoking status, presence of smokers at home, recent tobacco exposure, number of cigarettes smoked at home, and allowance of smoking at home and in vehicles significantly affected plasma cotinine levels.Global studies have shown that an estimated 40% of children were exposed to ETS in 2004\u0026nbsp;(12);\u0026nbsp;this is lower than the exposure rate found in our study population (58%) but similar to the ETS exposure rate in the last week (33.6%). In another study conducted in Turkey, in which 642 healthy children aged 8-12 participated, it was determined that 74% of the children had at least one parent smoking at home.\u0026nbsp;(13).\u0026nbsp;Although the rate in our study was lower, the 58% exposure rate for CLD patients is alarming. Since there is no known safe threshold for ETS that does not harm the respiratory system,\u0026nbsp;any exposure is likely harmful.\u003c/p\u003e\n\u003cp\u003eThe indoor exposure to tobacco smoke detected in our study (34.5%) is consistent with data from the USA (40.6%)\u0026nbsp;(14)\u0026nbsp;but higher than in England (12.7%)\u0026nbsp;(15).\u0026nbsp;However, it is important to note that while our study focused on children with CLD, the aforementioned studies were conducted on healthy children, and there may be differences due to cultural norms and legislative measures. For instance, the US and many European countries have implemented bans on tobacco use in public places since 2008.\u003c/p\u003e\n\u003cp\u003eAlthough there are reports on ETS exposure in children with BPD and CF in other countries, according to our knowledge, there have been no reports specifically on Turkish children with CLD. This study is significant as it examines not only BPD and CF patients but also other CLD patients, which includes BPD and CF. In a study evaluating tobacco exposure through a questionnaire administered to the parents of 113 BPD patients, it was found that 56% of them were exposed to tobacco smoke. In the same study, 131 preterm babies without BPD were also evaluated, and it was observed that these preterm babies had a similar ETS exposure rate (53%) to BPD patients\u0026nbsp;(16).\u0026nbsp;We found that 62.1% of 37 BPD patients in our study lived with at least one smoker in the same house, a rate higher than in the aforementioned study. In the literature, survey-based ETS exposure rates for CF patients have been reported between 10% and 76%\u0026nbsp;(9, 10, 17, 18). In our study, 70% of the 20 CF patients lived with at least one smoker in the same house. According to our results, not only BPD and CF patients but also nearly all CLD patients have very high ETS exposure rates, which is highly alarming. However, caution is needed when interpreting these results, as our study may reflect cultural norms that are not applicable to all children with chronic lung disease.\u003c/p\u003e\n\u003cp\u003eIt is known that people with higher cotinine levels are more likely to be affected by ETS exposure. In our study, based on plasma cotinine values, 72.4% of patients were exposed to ETS (plasma cotinine ≥12 ng/ml). In a study conducted in the USA between 2013 and 2016, which measured ETS exposure among healthy children aged 3-17 years using plasma cotinine, exposure was found to be 35.4%. In that study, plasma cotinine levels of 0.05-10 ng/ml were considered indicative of ETS exposure\u0026nbsp;(19).\u0026nbsp;Although our study used a higher plasma cotinine cutoff to define ETS exposure, it is concerning to find a higher exposure rate than reported in the aforementioned study, as ETS exposure can exacerbate existing lung and respiratory tract diseases in CLD patients. Another reason for the difference may be ethnic and racial differences in nicotine metabolism. Turkish people may have a slower nicotine metabolism than other nationalities. In a study comparing different ethnic groups living in the United States, Benowitz et al. suggested using ethnic-specific limit values\u0026nbsp;(28).\u0026nbsp;A review examining tobacco smoke exposure based on nicotine metabolites (urine or salivary cotinine) in CF patients reported exposure rates ranging from 44% to 54.8%\u0026nbsp;(7).\u0026nbsp;In our study, ETS exposure rates among CF patients based on plasma cotinine levels were higher (65%) compared to rates reported in the literature.\u003c/p\u003e\n\u003cp\u003eWe investigated variables affecting cotinine levels in children's plasma. We found that, maternal smoking status, presence of smokers at home, recent tobacco exposure, number of cigarettes smoked at home, and allowance of smoking at home and in vehicles significantly affected plasma cotinine levels. The number of smokers at home, type of home, and smoking location (indoors or outdoors) did not affect children's plasma cotinine levels. This suggests that where smoking occurs in the house, how many people smoke, or the type of household does not alter children's exposure. Although one study found that children whose parents smoke indoors have more respiratory symptoms than those whose parents smoke only outdoors (20)\u0026nbsp;we found no significant difference in plasma cotinine levels between those exposed to ETS outdoors or indoors. This is important evidence suggesting that outdoor ETS exposure is as harmful as indoor exposure. Since ETS negatively affects children's physical development, particularly lung development, and adversely affects respiratory tract and lung diseases\u0026nbsp;(1),\u0026nbsp;preventing ETS exposure is crucial, especially for children with CLD. Additionally, using an objective biomarker for ETS rather than just a questionnaire, may be useful in demonstrating that the belief that \" smoking outdoors is less harmful than smoking indoor\" is incorrect.\u003c/p\u003e\n\u003cp\u003eAmong 105 children (76.1%) not exposed to tobacco smoke at home, 50 out of 166 children (30.1%) not exposed to tobacco smoke in the last week, and 13 out of 45 children (28.8%) living in homes where tobacco consumption is not allowed, had plasma cotinine levels ≥ 12 ng/ml. This result suggests that questionnaire-based information alone may not be reliable in determining ETS exposure; it may be more reliable to use a questionnaire supported by biomarkers. One of the reasons for the discrepancy between the survey and plasma cotinine results in our study may be that parents provided incorrect information. Many previous studies have also shown discrepancies between parental reports and cotinine measurements in body fluids\u0026nbsp;(21-24).\u0026nbsp;A study of 115 children correlating parental reports with children's urinary cotinine levels found detectable urinary cotinine levels in 14% of children whose parents did not smoke\u0026nbsp;(25).\u0026nbsp;Similarly, in a study of 310 healthy and asthmatic children, 139 had detectable urinary cotinine levels despite being reported as unexposed by parental surveys\u0026nbsp;(26).\u0026nbsp;The accuracy of reporting ETS exposure by parents depends on the tools and population studied. Therefore, objective assessment of ETS exposure is crucial because the prevalence of ETS exposure is likely underestimated by survey results. Furthermore, most parental surveys cannot accurately distinguish between unexposed children and those mildly exposed to ETS. These findings underscore the need for increased awareness of ETS exposure risks and the implementation of comprehensive tobacco control strategies that go beyond eliminating active smoking to prevent chronic ETS exposure, particularly in pediatric CLD populations.\u003c/p\u003e\n\u003cp\u003eOne of the main strengths of this study is its relatively large and heterogeneous sample of pediatric patients with CLD, covering a broad range of diagnoses beyond only BPD and CF. The use of both parental questionnaires and an objective biomarker (plasma cotinine) enhances the reliability of ETS exposure assessment. Moreover, it is one of the few studies in the Turkish pediatric population to investigate ETS exposure using biochemical validation. However, the study also has certain limitations. First, the possibility of including adolescent participants who may have been active smokers, despite self-reporting as non-smokers, cannot be excluded. Accurately assessing exposure to active and passive smoking is essential, particularly for children (27). In adolescents, active smoking is also a significant health issue. Second, the heterogeneity of the study group limits disease-specific interpretations. Finally, the absence of a nationally validated plasma cotinine cutoff value for ETS exposure in Turkish children may affect the generalizability of the biochemical classification. Future studies could examine each disease group separately to reveal more specific results. Furthermore, large-scale population studies could be conducted to determine the cotinine cutoff value for Turkish children.\u0026nbsp;\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, the rate of exposure to ETS was high in our study among patients with CLD. Parents of these patients should be questioned about their smoking status, reminded of the dangers of ETS exposure to their children and encouraged to quit smoking. Measurement of plasma cotinine could be routinely used for objective data screening for tobacco smoke exposure in this vulnerable population. However, since there is no generally accepted plasma cotinine level to detect ETS exposure in Turkish children, further studies are necessary to determine a cutoff value specific to this population.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003e\u003cstrong\u003eBPD:\u003c/strong\u003e Bronchopulmonary dysplasia\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCF:\u003c/strong\u003e Cystic fibrosis\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCLD:\u003c/strong\u003e Chronic lung diseases \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eETS:\u003c/strong\u003e Environmental tobacco smoke\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSHS:\u003c/strong\u003e Secondhand tobacco smoke\u003c/p\u003e"},{"header":"Statements and Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cu\u003eFunding\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by Ankara University Scientific Research Projects (Project Number: 20L0230009).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eCompeting Interests\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eAuthor Contributions\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eMaterial preparation, data collection, analysis and writing were performed by Merve Setenay Akyüzlüer Güneş.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eData collection, study design were performed by Fazılcan Zirek, Gizem Özcan, Mervenur Tekin.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAnalysis of the samples \u003cem\u003ewas performed by\u0026nbsp;\u003c/em\u003eFiliz Bakar Ateş, Erva Özkan.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStudy conception, design and writing were performed by Nazan Çobanoğlu.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eThe first draft of the manuscript was written by Merve Setenay Akyüzlüer Güneş and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eEthical Approval:\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was conducted in accordance with the principles of the Declaration of Helsinki. Ethical approval was obtained from the Clinical Research Ethics Committee of Ankara University (Decision No: 10-793-19, May 27, 2019).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cu\u003eConsent to participate\u003c/u\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eInformed consent was obtained from all individual participants included in the study.\u003c/em\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHealth UDo, Services H. The health consequences of smoking\u0026mdash;50 years of progress: a report of the Surgeon General. Atlanta, GA: US Department of Health and Human Services, Centers for Disease \u0026hellip;; 2014.\u003c/li\u003e\n\u003cli\u003eBrook I, Gober AE. Recovery of potential pathogens in the nasopharynx of healthy and otitis media\u0026mdash;prone children and their smoking and nonsmoking parents. Annals of Otology, Rhinology \u0026amp; Laryngology. 2008;117(10):727-30.\u003c/li\u003e\n\u003cli\u003eStrachan DP, Cook DG. Health effects of passive smoking. 1. Parental smoking and lower respiratory illness in infancy and early childhood. Thorax. 1997;52(10):905.\u003c/li\u003e\n\u003cli\u003eStocks J, Dezateux C. The effect of parental smoking on lung function and development during infancy. Respirology. 2003;8(3):266-85.\u003c/li\u003e\n\u003cli\u003eWongtrakool C, Wang N, Hyde DM, Roman J, Spindel ER. Prenatal nicotine exposure alters lung function and airway geometry through \u0026alpha;7 nicotinic receptors. American journal of respiratory cell and molecular biology. 2012;46(5):695-702.\u003c/li\u003e\n\u003cli\u003eCheraghi M, Salvi S. Environmental tobacco smoke (ETS) and respiratory health in children. European journal of pediatrics. 2009;168(8):897-905.\u003c/li\u003e\n\u003cli\u003eKopp BT, Ortega-Garc\u0026iacute;a JA, Sadreameli SC, Wellmerling J, Cormet-Boyaka E, Thompson R, et al. The impact of secondhand smoke exposure on children with cystic fibrosis: a review. International journal of environmental research and public health. 2016;13(10):1003.\u003c/li\u003e\n\u003cli\u003eCollaco JM, Aherrera AD, Breysse PN, Winickoff JP, Klein JD, McGrath-Morrow SA. Hair nicotine levels in children with bronchopulmonary dysplasia. Pediatrics. 2015;135(3):e678-e86.\u003c/li\u003e\n\u003cli\u003eSanders DB, Emerson J, Ren CL, Schechter MS, Gibson RL, Morgan W, et al. Early childhood risk factors for decreased FEV1 at age six to seven years in young children with cystic fibrosis. Annals of the American Thoracic Society. 2015;12(8):1170-6.\u003c/li\u003e\n\u003cli\u003eVerma A, Clough D, McKenna D, Dodd M, Webb AK. Smoking and cystic fibrosis. Journal of the Royal Society of Medicine. 2001;94(40_suppl):29-34.\u003c/li\u003e\n\u003cli\u003eAvila-Tang E, Al-Delaimy WK, Ashley DL, Benowitz N, Bernert JT, Kim S, et al. Assessing secondhand smoke using biological markers. Tobacco control. 2013;22(3):164-71.\u003c/li\u003e\n\u003cli\u003eOberg M, Jaakkola M, Woodward A, Peruga A, Pr\u0026uuml;ss-Ust\u0026uuml;n A. Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries [published online ahead of print November 26, 2010]. Lancet.61388-8.\u003c/li\u003e\n\u003cli\u003eKarako\u0026ccedil; F, Dağlı E, Kut A, Pamuk\u0026ccedil;u A. \u0026Ccedil;ocuklarda pasif sigaraya maruziyetin serum kotinin d\u0026uuml;zeyi ile değerlendirilmesi. T\u0026uuml;rkiye Klinikleri J Pediatr. 1998;7(2):77-82.\u003c/li\u003e\n\u003cli\u003eHoma DM, Neff LJ, King BA, Caraballo RS, Bunnell RE, Babb SD, et al. Vital signs: disparities in nonsmokers\u0026rsquo; exposure to secondhand smoke\u0026mdash;United States, 1999\u0026ndash;2012. MMWR Morbidity and mortality weekly report. 2015;64(4):103.\u003c/li\u003e\n\u003cli\u003eJarvis MJ, Feyerabend C. Recent trends in children\u0026apos;s exposure to second‐hand smoke in England: cotinine evidence from the Health Survey for England. Addiction. 2015;110(9):1484-92.\u003c/li\u003e\n\u003cli\u003eMartinez S, Garcia-Meric P, Millet V, Aymeric-Ponsonnet M, Alagha K, Dubus J-C. Tobacco smoke in infants with bronchopulmonary dysplasia. European journal of pediatrics. 2015;174(7):943-8.\u003c/li\u003e\n\u003cli\u003eKopp BT, Sarzynski L, Khalfoun S, Hayes Jr D, Thompson R, Nicholson L, et al. Detrimental effects of secondhand smoke exposure on infants with cystic fibrosis. Pediatric Pulmonology. 2015;50(1):25-34.\u003c/li\u003e\n\u003cli\u003eRen CL, Rosenfeld M, Mayer OH, Davis SD, Kloster M, Castile RG, et al. Analysis of the associations between lung function and clinical features in preschool children with cystic fibrosis. Pediatric pulmonology. 2012;47(6):574-81.\u003c/li\u003e\n\u003cli\u003eBrody DJ, Lu Z, Tsai J. Secondhand smoke exposure among nonsmoking youth: United States, 2013\u0026ndash;2016. 2019.\u003c/li\u003e\n\u003cli\u003eJohansson A, Halling A, Hermansson G. Indoor and outdoor smoking: Impact on children\u0026apos;s health. The European Journal of Public Health. 2003;13(1):61-6.\u003c/li\u003e\n\u003cli\u003eClark S, Warner J, Dean T. Passive smoking amongst asthmatic children. Questionnaire or objective assessment? Clinical \u0026amp; Experimental Allergy. 1994;24(3):276-80.\u003c/li\u003e\n\u003cli\u003eDerauf C, Katz AR, Easa D. Agreement between maternal self-reported ethanol intake and tobacco use during pregnancy and meconium assays for fatty acid ethyl esters and cotinine. American Journal of Epidemiology. 2003;158(7):705-9.\u003c/li\u003e\n\u003cli\u003eGunay F, Cullas Ilarslan NE, Bakar‐Ates F, Deniz K, Kadioglu YK, Kiran S, et al. Evaluation of hair cotinine and toxic metal levels in children who were exposed to tobacco smoke. Pediatric pulmonology. 2020;55(4):1012-9.\u003c/li\u003e\n\u003cli\u003eNafstad P, Botten G, HAGEN JA, ZAHLSEN K, Nilsen OG, Silsand T, et al. Comparison of three methods for estimating environmental tobacco smoke exposure among children aged between 12 and 36 months. International Journal of Epidemiology. 1995;24(1):88-94.\u003c/li\u003e\n\u003cli\u003eJurado D, Mu\u0026ntilde;oz C, Luna JDD, Fern\u0026aacute;ndez-Crehuet M. Environmental tobacco smoke exposure in children: parental perception of smokiness at home and other factors associated with urinary cotinine in preschool children. Journal of exposure science \u0026amp; environmental epidemiology. 2004;14(4):330-6.\u003c/li\u003e\n\u003cli\u003eCallais F, Momas I, Roche D, Gauvin S, Reungoat P, Zmirou D. Questionnaire or objective assessment for studying exposure to tobacco smoke among asthmatic and healthy children: The French VESTA Study. Preventive medicine. 2003;36(1):108-13.\u003c/li\u003e\n\u003cli\u003eFlorescu A, Ferrence R, Einarson T, Selby P, Soldin O, Koren G. Methods for quantification of exposure to cigarette smoking and environmental tobacco smoke: focus on developmental toxicology. Therapeutic drug monitoring. 2009;31(1):14.\u003c/li\u003e\n\u003cli\u003eBenowitz NL, Bernert JT, Caraballo RS, Holiday DB, Wang J. Optimal serum cotinine levels for distinguishing cigarette smokers and nonsmokers within different racial/ethnic groups in the United States between 1999 and 2004. American journal of epidemiology. 2009;169(2):236-48.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003eDemographic characteristics of the patients and their parents\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003eMean\u0026plusmn;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e5,97\u0026plusmn;5,44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003eMedian (Min.-Max.)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e4,00 (0,08-18,00)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGender, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e106 (42.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e144 (57.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBody Weight, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026lt;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e73 (29.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026ge;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e177 (70.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHeight, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026lt;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e68 (27.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026ge;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e182 (72.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBirth Week, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026lt;37 week\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e86 (34.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026ge;37 week\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21px;\"\u003e\n \u003cp\u003e164 (65.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"5\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBirth Weight, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026lt;1500 gram\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e39 (15.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e1500-1999 gram\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e15 (6.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e2000-2499 gram\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e26 (10.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e2500-4000 gram\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e161 (64.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003e\u0026gt;4000 gram\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e9 (3.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMother\u0026apos;s Educational Status, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eIlliterate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e17 (6.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003ePrimary education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e178 (71.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eUndergraduate and higher\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e55 (22)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eFather\u0026apos;s Educational Status, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eIlliterate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e2 (0.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003ePrimary education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e175 (70)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eUndergraduate and higher\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e73 (29.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIncome, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eMinimum wage and lower\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e80 (32.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 26px;\"\u003e\n \u003cp\u003eMore than minimum wage\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e170 (67.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTypes of house, n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003ePrivate\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e31 (12.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 52px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 26px;\"\u003e\n \u003cp\u003eApartment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 21px;\"\u003e\n \u003cp\u003e219 (87.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2.\u003c/strong\u003e Diseases in the study group\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDisease\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNumber of Patients (n)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAspiration Syndromes\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e17.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBPD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e14.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePectus Deformities\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e13.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-CF Bronchiectasis\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e9.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCF\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBronchiolitis Obliterans\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCentral Hypoventilation Syndromes\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLung and Respiratory Problems Due to Neuromuscular Diseases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e5.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOthers\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e18.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e- Childhood Interstitial and Diffuse Lung Diseases\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Tracheobronchomalacia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Congenital Lung Malformations\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Diaphragmatic Hernia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Obstructive Sleep Apnea Syndrome\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Subglottic Stenosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Alpha-1 Antitrypsin Deficiency\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Diaphragmatic eventration\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Hepatopulmonary syndrome\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003e-Plastic Bronchitis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 65px;\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e250\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 14px;\"\u003e\n \u003cp\u003e100\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\u003e\u003cstrong\u003eTable 3.\u0026nbsp;\u003c/strong\u003eEnvironmental tobacco smoke exposure information of patients based on survey\u003c/p\u003e\n\u003cdiv align=\"center\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAre there any tobacco consumers living in the same house?; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e105 (42.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e145 (58.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoker mother; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e188 (75.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e62 (24.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoker father; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e141 (56.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e109 (43.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTobacco consumption allowed in the car; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e112 (58.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e80 (41.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eDo not have a car\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTobacco consumption allowed in the house; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e45 (18.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e205 (82.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIn which areas of the house is tobacco consumption allowed?; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eIndoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e32 (15.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eOutdoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e173 (84.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHas the child been exposed to tobacco smoke in the last seven days?; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e166 (66.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e84 (33.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWhere the child has been exposed to tobacco smoke in the last seven days?; n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eIndoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e29 (34.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 23px;\"\u003e\n \u003cp\u003eOutdoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 19px;\"\u003e\n \u003cp\u003e55 (65.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAmount of Cigarettes Smoked Daily; n (%)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 23px;\"\u003e\n \u003cp\u003eLess than 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e38 (26.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 23px;\"\u003e\n \u003cp\u003e10-20\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e38 (26.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 23px;\"\u003e\n \u003cp\u003eMore than 20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 19px;\"\u003e\n \u003cp\u003e69 (47.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4.\u0026nbsp;\u003c/strong\u003eEnvironmental tobacco smoke exposure rates of disease groups based on survey. BPD: Bronchopulmonary dysplasia, CF: Cystic fibrosis, HSCT: Hematopoetic stem cell transplantation.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"662\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDisease Groups (n)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDisease Groups (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatients living in the same house with at least one smoker\u003c/strong\u003e\u003cstrong\u003e, n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTobacco consumption allowed in the car, n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTobacco consumption allowed in the house, n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatients has been exposed to tobacco smoke in the last seven days, n(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAspiration Syndromes (44)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e17.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e30(68.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e16(36)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e37(84)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e11(25)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBPD (37)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e14.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e23(62.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10(27)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e25(67.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e8(21.6)\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePectus Deformities (33)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e13.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e16(48.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e8(24.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e30(90.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e14(42.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNon-CF Bronchiectasis (23)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e9.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e14(60.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e7(30.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e18(78.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e9(39.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCF (20)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e14(70)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e7(35)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e16(80)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e8(40)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBronchiolitis Obliterans Syndrome (post-infectious or post HSCT) (17)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e8(47)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e4(23.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e14(82.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e4(23.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCentral Hypoventilation Syndromes (17)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e8(47)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e3(17.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e13(76.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e4(23.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLung and Respiratory Problems Due to Neuromuscular Diseases \u0026nbsp;(13)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e5.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e2(15.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e3(23)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e8(61.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e1(7.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 146px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eOthers (46)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e- \u003cem\u003eChildhood Interstitial and Diffuse Lung Diseases\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Tracheobronchomalacia\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Congenital Lung Malformations\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Diaphragmatic Hernia\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Obstructive Sleep Apnea Syndrome\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Subglottic Stenosis\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Alpha-1 Antitrypsin Deficiency\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Diaphragmatic eventration\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Hepatopulmonary syndrome\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u003cem\u003e-Plastic Bronchitis\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e18.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e31(67.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e10(21.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e38(82.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e10(21.7)\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\u003e\u003cstrong\u003eTable 5.\u003c/strong\u003e Comparison of patients\u0026apos; cotinine levels according to the variables\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"523\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"2\" rowspan=\"2\" style=\"width: 338px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCotinine (ng/ml)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean.\u0026plusmn;SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGender\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eFemale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e29,43\u0026plusmn;26,12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,267\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eMale\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e30,45\u0026plusmn;23,49\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBody weight\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026lt;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e28,42\u0026plusmn;25,56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,183\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026ge;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e30,68\u0026plusmn;24,22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHeight\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026lt;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e29,40\u0026plusmn;25,76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,480\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026ge;3p\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e30,24\u0026plusmn;24,21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLiving in the same house with at least one smoker\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e21,57\u0026plusmn;12,76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0,005\u003csup\u003ea\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e34,76\u0026plusmn;28,16\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTobacco smoke exposure in the last week\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e23,66\u0026plusmn;14,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0,001\u003csup\u003ea\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e42,58\u0026plusmn;33,61\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMaternal Tobacco Consumption\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e25,48\u0026plusmn;17,53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0,007\u003csup\u003ea\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e43,76\u0026plusmn;35,65\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePaternal Tobacco Consumption\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e31,61\u0026plusmn;26,29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,301\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e27,96\u0026plusmn;22,15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking Allowed in the Car\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e21,00\u0026plusmn;13,94\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026lt;0,001\u003csup\u003ea\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e40,71\u0026plusmn;30,52\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSmoking Allowed at Home\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e20,42\u0026plusmn;11,80\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0,031\u003csup\u003ea\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e32,12\u0026plusmn;26,14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAmount of Cigarettes Smoked Daily\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eLess than 10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e20,63\u0026plusmn;13,86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0,005\u003csup\u003eb\u003c/sup\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e10-20\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e24,91\u0026plusmn;18,44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eMore than 20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e38,82\u0026plusmn;30,15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType of House\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003ePrivate\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e26,84\u0026plusmn;24,64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,257\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eApartment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e30,46\u0026plusmn;24,61\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRespiratory Support\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e29,14\u0026plusmn;23,09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,862\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e32,26\u0026plusmn;28,13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eRespiratory Support Type\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eInvasive mechanical ventilation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e20,57\u0026plusmn;14,20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,094\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNon-invasive mechanical ventilation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e21,26\u0026plusmn;32,29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003eNasal Oxygen\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e32,28\u0026plusmn;28,43\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLocations Exposed to Tobacco Smoke in the Last Seven Days\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eOutdoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e31,24\u0026plusmn;31,60\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,420\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eIndoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e33,46\u0026plusmn;26,44\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNumber of People Using Tobacco in the Same House\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e31,43\u0026plusmn;24,89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,184\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u0026ge;2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e28,40\u0026plusmn;25,83\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 225px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAreas Where Tobacco Use Is Allowed at Home\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eIndoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e27,84\u0026plusmn;22,73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0,540\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eOutdoors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 125px;\"\u003e\n \u003cp\u003e31,51\u0026plusmn;25,83\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ea:Mann-Whitney U test, b:Kruskal Wallis H test, SD: Standard deviation, Min: Minimum, Max: Maximum, p: Percentile\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6.\u003c/strong\u003e Environmental tobacco smoke exposure rates of disease groups based on plasma cotinine values. BPD: Bronchopulmonary dysplasia, CF: Cystic fibrosis, HSCT: Hematopoetic stem cell transplantation.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"576\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDisease Groups (n)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePlasma cotinine\u0026nbsp;\u003c/strong\u003e\u0026ge;\u003cstrong\u003e\u0026nbsp;12 ng/ml\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003en(%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eNon-CF Bronchiectasis (23)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e20(86.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eBronchiolitis Obliterans Syndrome (post-infectious or post HSCT) (17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e14(82.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eBPD (37)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e30(81)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003ePectus Deformities (33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e25(75.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eAspiration Syndromes (44)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e31(70.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eOthers (46)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e30(65.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eCF (20)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e13(65)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eCentral Hypoventilation Syndromes (17)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e11(64.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 382px;\"\u003e\n \u003cp\u003eLung and Respiratory Problems Due to Neuromuscular Diseases \u0026nbsp; \u0026nbsp; (13)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 194px;\"\u003e\n \u003cp\u003e8(61.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\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":"cotinine, children, environmental tobacco smoke, chronic lung disease, second hand tobacco smoke, third hand tobacco smoke","lastPublishedDoi":"10.21203/rs.3.rs-7228175/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7228175/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose: \u003c/strong\u003eIt is very important to minimize the environmental risks that may increase respiratory morbidity in children with chronic lung diseases (CLD). We aimed to determine environmental tobacco smoke (ETS) exposure in children with CLD.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e Two hundred and fifty patients with the diagnosis of CLD were included in this study. Parents of the children with CLD were asked about their smoking habits through a questionnaire. ETS exposure was also determined by the measurement of plasma cotinine level of these children, and levels ≥12 ng/ml were considered exposed to ETS.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Although according to parental reports 58% of patients lived in the same household with at least one smoker, 72% of patients had a plasma cotinine level of ≥12 ng/ml. Cotinine values of children who lived in the same house with at least one smoker, were exposed to ETS in the last 7 days and whose parents allowed smoking in their car were significantly higher than the opposite groups (34,76±28,16 versus 21,57±12,76; 42,58±33,61 versus 23,66±14,94; and 40,71±30,52 and 21,00±13,94 ng/ml respectively).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eThis study revealed that children with CLD exhibited significantly elevated plasma cotinine levels. It emphasizes the critical need to reduce ETS exposure in CLD patients. Objective measures like plasma cotinine can provide reliable assessments of exposure, complementing parental reports which may underestimate actual exposure levels. Moving forward, efforts to mitigate ETS exposure among CLD patients should include targeted smoking cessation interventions and stricter enforcement of smoke-free policies in homes and public spaces.\u003c/p\u003e","manuscriptTitle":"Evaluation of Environmental Tobacco Smoke Exposure of Pediatric Patients with Chronic Lung Diseases","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-31 15:59:38","doi":"10.21203/rs.3.rs-7228175/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":"782b66e4-8e38-4737-8582-1e18245525d5","owner":[],"postedDate":"July 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-25T17:53:24+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-31 15:59:38","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7228175","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7228175","identity":"rs-7228175","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}