Association between low daily average temperature and epilepsy outpatient visits: a hospital-based study in...

Epilepsy is a neurological disorder that significantly impacts individuals and society, contributing to the global disease burden. However, research on the association between meteorological factors and epilepsy across all age groups remains limited. To investigate the relationship between daily average temperature and epilepsy outpatient visits in Chongqing, the most populous city in western China, and to assess susceptibility differences by gender and age. We employed distributed lag non-linear models (DLNM) to investigate the association between daily average temperature and epilepsy outpatient visits from January 2014 to December 2019 (a total of 2,191 days) in Chongqing. Additionally, we conducted subgroup analyses based on gender and age. During the study period, a total of 99,740 outpatient visits for epilepsy were recorded. Using the median daily average temperature (19.5 °C) as a reference, the single-day lag risk ratio (RR) of a low daily average temperature (5th percentile, 7.8 °C) on outpatient visits for epilepsy showed a persistent decrease throughout the entire lag period (from lag 0 to lag 12) and remained statistically significant from lag 0 to lag 3, with values of 1.05 (95% CI: 1.01, 1.10), 1.04 (95% CI: 1.01, 1.07), 1.03 (95% CI: 1.01, 1.05), and 1.02 (95% CI: 1.00, 1.05), respectively. The cumulative RR peaked at lag 0-8 (RR: 1.22, 95% CI: 1.08, 1.36), and then remained relatively stable. The association between higher daily average temperatures and epilepsy outpatient visits was not statistically significant. Subgroup analyses indicated that males and individuals under 18 and over 65 years old were more vulnerable to the effects of low ambient temperatures on epilepsy risk. Season acts as an effect modifier in the association between low daily average temperature and epilepsy outpatient visits.