Mental health impacts from repeated climate disasters: an australian longitudinal analysis.

Background: Extreme weather events are becoming more frequent and intense under changing climatic conditions. Whilst there is substantial evidence that exposure to a single weather related disaster is detrimental for mental health, few studies have explored how exposure to multiple disasters impacts mental health. Methods: We utilised 11 waves of data from the Household, Income and Labour Dynamics in Australia (HILDA) Survey, yielding a sample of 16,629 observations from 2003 individuals. Fixed effects linear regression analysis was used to estimate the impact of experiencing multiple disasters on mental health. We tested for effect modification on this association by sex, rurality, employment and presence of a long-term health condition. Findings: Exposure to multiple disasters was associated with a relative decrease in MHI-5 score compared to baseline by -1.8 points (95% CI -3.4, -0.3), whereas exposure to a single disaster was not associated with a decline in mental health scores. There was evidence of effect modification by employment status. Unemployed individuals had evidence of moderate reduction in MHI-5 scores when exposed to a single disaster (-4.3, 95% CI -7.0, -1.5). Interpretation: Findings suggest that repeat exposure to disasters is associated with worsening mental health outcomes. As extreme weather events increase, these findings highlight the need for greater attention on climate change action, and mental health interventions targeting impacted populations. Funding: Suicide Prevention Australia.