Modification effects of socioeconomic, demographic, and geographic factors on the association between temperature and cause-specific mental disorders among Taiwanese population

Objectives

This study investigates the association between extreme temperatures and the burden of age-sex-cause-specific mental disorders (MDs) from 2009 to 2019 in Taiwan and the modifying effects of socioeconomic, demographic, and geographic factors.

Methods

Daily records of MDs were collected from the National Health Insurance database. The distributed lag non-linear model was employed to assess age (0–18, 19–44, 45–64, and 65+), sex, and cause-specific (drug abuse, schizophrenia, mood disorders, and dementia) of MDs associated with extremely low (5th percentile) and high (99th percentile) temperatures considering a cumulative lag of 21 days. Random-effects meta-analysis was used to investigate the pooled relative risks of all MDs modified by socioeconomic, demographic, and geographic factors.

Results

Extreme high temperatures (30.1 °C) significantly impacted cause-specific MDs at a lag of 14 and 21 days, while extreme low temperatures (14.2 °C) had predominant effects at a lag of 3 and 10 days. There was a heightened risk for all MDs among males aged 65 + following exposure to extreme high temperatures at a lag of 21 days (RR: 1.18; 95% CI: 1.11–1.25). Extreme high temperatures increased the risk of drug abuse among females aged 45–64 (RR: 1.33; 95% CI: 1.05–1.68), mood disorder among males aged 65+ (RR: 1.17; 95% CI: 1.02–1.35), and dementia among males and females aged 65+, with an RR of 1.19. The study noted variations in the modifying effect of socio-economic-geographic factors on temperature across all MDs.

Conclusion

Our data highlight underlying heterogeneity in risk that is associated with specific climate hazards on cause-specific MDs.