Exposure to environmental toxicants and obstructive sleep apnea: a cross-sectional study

OBJECTIVE: To evaluate associations between environmental toxicant (ET) exposures and obstructive sleep apnea (OSA) using an exposome-wide approach. METHODS: This cross-sectional analysis included 13,161 participants from two NHANES cycles (2015-2016 and 2017-March 2020). Fifty-six toxicants across six classes (arsenic species, ethylene oxide, heavy metals, nicotine metabolites, VOC metabolites, and thyroid-disrupting compounds) were measured. OSA status was defined using a validated questionnaire based on self-reported symptoms. Exposome-wide association analysis (ExWAS) adjusted for sociodemographic, lifestyle, and clinical covariates, and restricted cubic spline (RCS) analysis characterized nonlinear exposure-response relationships. RESULTS: = 6,443). Nine ETs showed significant associations with OSA, including blood and urinary cadmium, seven volatile organic compound metabolites (e.g., 2,5-dimethylfuran, ethylbenzene, furan, o-xylene), and three urinary cysteine-derived metabolites (N-acetylcysteine derivatives). Subgroup analyses revealed higher susceptibility among women and individuals aged <65 years. RCS analyses demonstrated nonlinear, nonmonotonic relationships for cadmium and cysteine-derived metabolites with OSA prevalence. CONCLUSIONS: Nine ETs were significantly associated with OSA prevalence, with evidence of differential susceptibility by sex and age. These findings highlight environmental factors associated with OSA, which may serve as potential targets for future mechanistic research and public health interventions.