Occupational exposures to irritants and sensitizers, asthma and asthma control in the NutriNet-Santé cohort

International audienceBACKGROUND: The role of chronic occupational exposures to irritants in asthma remains not well-defined. Few studies have examined their associations with asthma and its control. OBJECTIVE: To study the associations of occupational exposures with asthma and its control, with specific interest for irritants, including disinfectants/cleaning products (DCP) and solvents.METHODS: Analyses included 4469 adults (3792 with neither asthma nor respiratory symptoms, 677 with current asthma; 75.9% women, mean age 54 years) of a case-control study (2018) from the French NutriNet-Santé cohort. Current asthma was defined by ever asthma with symptoms, medication or asthma attacks in the past 12 months, adult-onset asthma by age at first asthma attack > 16 years, and uncontrolled asthma was defined by an Asthma Control Test (ACT) score <20. Ever/current exposures were assessed with the Occupational Asthma-specific Job-Exposure Matrix (OAsJEM). Associations were evaluated by multinomial logistic regressions adjusted for sex, age, smoking status and body mass indexRESULTS: Ever exposures to sensitizers (High Molecular Weight [HMW]: OR 1.53, 95%CI 1.18-2.00, and Low Molecular Weight [LMW]: 1.42, 1.09-1.87), irritants (1.32, 1.03-1.68), and DCP (1.43, 1.10-1.85) were associated with current adult-onset asthma. Significant associations between ever exposures and uncontrolled adult-onset asthma were observed for HMW (2.69, 1.52-4.78) and LMW (2.27, 1.24-4.37) sensitizers, irritants (2.32, 1.36-3.95), and DCP (2.59, 1.48-4.54). Results were similar for current exposures, with higher ORs. No association was observed with solvents. CONCLUSION: Occupational exposures to both sensitizers and irritants were associated with current adult-onset asthma and uncontrolled asthma. Irritant and sensitizing agents should be carefully considered in asthma management