Associations Between Obstructive Sleep Apnea and Cotinine: A Cross-Sectional Study Based on 2015–2020 NHANES

OBJECTIVE: To investigate the associations between tobacco exposure biomarkers (serum/urinary cotinine) and questionnaire-defined obstructive sleep apnea (OSA) using nationally representative data. BACKGROUND: Tobacco exposure may be associated with higher odds of OSA through airway inflammation and oxidative stress, but population-level evidence linking cotinine, a nicotine metabolite, to OSA remains limited. METHODS: We used the National Health and Nutrition Examination Survey (NHANES) Sleep Questionnaire to identify participants with OSA.Participants were classified into four groups-nonsmokers, secondhand smoke (SHS) exposed, smokers, and heavy smokers - based on serum cotinine levels. Multivariable logistic regression, subgroup analyses, and sensitivity analyses were conducted to examine associations between cotinine levels and questionnaire-defined OSA. RESULTS: = .02). CONCLUSIONS: Both active smoking and SHS exposure are positively associated with higher odds of questionnaire-defined OSA.