Heat exposure and hospital admissions for mental health disorders in a changing climate

This study examines associations between ambient temperature and hospital admissions for mental health disorders among children, adolescents and young adults, and to project future heat-attributable admissions under various climate change scenarios. The authors conducted a case-crossover time-series study using hospital admissions for mental health disorders in New South Wales, Australia (2001-2022). Daily average temperature was the exposure.

The results indicate that among 719,375 admissions, high temperature was associated with increased admissions: RR 3.03 (95%CI 2.56–3.60) in cold seasons and 1.92 (95%CI 1.58–2.34) in warm seasons. Elevated risks were observed for substance use, depressive, anxiety, obsessive-compulsive, reaction and adjustment, and attention-deficit, disruptive, impulse-control disorders in both seasons (RR range 2.02-5.49), and for schizophrenia, eating disorders, and deliberate self-harm in cold seasons (2.22-5.23), but no effect was observed for manic episode and bipolar disorders in either season.