Sleep apnea and pesticide exposure in a study of US farmers

Carbamate and organophosphate pesticides inhibit acetylcholinesterase, and poisoning leads to respiratory depression. Thus, involvement in sleep apnea is plausible, but no data exist at lower levels of exposure. Other pesticides could impact sleep apnea by different mechanisms but have not been studied. Our study examines the associations between pesticide exposure and sleep apnea among pesticide applicators from a US farming population. We analyzed data from 1569 male pesticide applicators, mostly farmers, from an asthma case-control study nested within the prospective Agricultural Health Study. On questionnaires, participants reported use of specific pesticides and physician diagnosis plus prescribed treatments for sleep apnea. We used multivariable logistic regression to estimate associations between ever use of 63 pesticides and sleep apnea (234 cases, 1335 noncases). The most notable association was for carbofuran, a carbamate (100 exposed cases, odds ratio 1.83, 95% confidence interval 1.34-2.51, P=.0002). Carbofuran use began before reported onset of sleep apnea in all cases. This study adds to the known adverse health outcomes of exposure to carbofuran, a pesticide canceled in the United States in 2009 for most agricultural purposes but persists in the environment and remains in use in some other countries. We conducted the first epidemiological study investigating the association of pesticide exposure and sleep apnea. Our results in a male agricultural population suggests that exposure to carbofuran is positively associated with sleep apnea.