Increased ozone exposure is associated with decreased risk of epilepsy: A hospital-based study in southwest China

To investigate the association between O3 and the number of outpatient visits for epilepsy in Chongqing, the most populous municipality in China, we conducted a time-series study including 99,740 epilepsy outpatient visits from January 2014 to December 2019 (2191 days). During the study period, the mean maximum 8-h average O3 was 70.63 μg/m3, which was below the WHO guideline (100 μg/m3). Negative and statistically significant associations of O3 were observed at lag 0, lag 1, and lag 01 to lag 03. Meanwhile, O3 exposure of lag 03 yielded the strongest estimates for outcomes: per 10-μg/m3 increase in O3 at lag 03 corresponded to −0.770% (95% CI: −1.419%, −0.122%) decrease in outpatient visits for epilepsy. In addition, the effect estimates were stronger in females than in males, in people aged ≥65 years than in younger populations, and in cool seasons than in warm seasons. Taken together, there was a significant negative association between short-term exposure to low concentrations of O3 and outpatient visits for epilepsy. These findings may contribute to the understanding of the relationship between air pollutants and epilepsy and other neurological diseases. [Display omitted] •Low concentrations of O3 were negatively associated with epilepsy outpatient visits.•The association was stronger in cool seasons.•The association was more evident in females and elderly (≥65 years).