High Ambient Temperatures Increase Outpatient Visits for Sleep Disorders in Hefei City, China

Objective: To analyze the impact of ambient temperature on the quantity of outpatient clinic visits for sleep disorders. Methods: Using data from sleep disorder outpatient visits in a large tertiary hospital in Hefei City, a distributional lag nonlinear model combined with a generalized Poisson regression model was used to analyze the relationship between ambient temperature and the number of outpatient visits for sleep disorders. Results: Ambient temperatures above 17.2℃ were found to be connected with a higher prevalence of sleep disorders visits, and that this relationship was most significant on day 8, which lasted for 7 days. For the single-day lagged impact, the maximum relative risk (RR) for moderate heat (75th percentile) was 1.077 (95% CI: 1.015–1.143). The cumulative lag effect was substantially greater than the single-day lag effect, with a maximum relative risk (RR) of 2.609 (95% CI: 1.306–5.212). The longest lag time was 14 days. The RR was similarly greater in women and those over 40. Outpatient visits for men with sleep disorders were not affected by ambient temperature in a statistically significant way. Conclusion: High ambient temperature raises the risk that patients will visit an outpatient facility and serves as a risk factor for sleep disorders. Patients who were 40 years of age or older and women were at vulnerability.