8288333 Does the duration of exposure to night work modify the 10-year risk of cardiovascular disease? results from constances, a French population-based cohort

<h3>Objective</h3> To evaluate the effect of the duration of exposure to night work on the 10-year risk of cardiovascular disease (SCORE2). <h3>Material and Methods</h3> Based on the Constances cohort, 52,234 participants divided into day and night workers (permanent, rotating and former night workers) were included. The duration of exposure to night work was assessed over the entire working career using a self-reported questionnaire. The 10 year-cardiovascular disease risk was assessed using the SCORE2, following recently established guidelines and based on the main cardiovascular factors measured. Generalized additive models were used to estimate the probability of having a moderate or high SCORE2 (OR and 95% confidence intervals) as a function of the duration of exposure for each category of night workers. <h3>Results</h3> The sample consisted of 24,892 men and 27,342 women, with an average working career of 20 years. Among them, 685 permanent night workers, 915 rotating night workers and 2,972 former night workers were identified. Compared to daytime workers, the ORs for a moderate or high SCORE2 were 1.43 [1.23-1.66] for permanent, 1.72 [1.51-1.97] for rotating and 2.01 [1.87-2.18] for former night workers. As the cumulative duration of exposure increased, the probability of having a moderate and high SCORE2 increased. Indeed, significant excess risk was observed from 10 years of cumulative exposure in permanent night workers (OR=1.28) and rotating night workers (OR=1.48). In former night workers, this significant excess risk was observed from 5 years of cumulative exposure (OR=1.82). <h3>Conclusion</h3> These results from a French cohort confirm a high 10-year risk of developing cardiovascular disease in night workers, with a significant effect from 10 years of exposure. The risk remains among former night workers despite the cessation of exposure. These results reinforce the need to monitor cardiovascular risk in this type of worker, even after stopping night work.