Meta-analysis on risk factors for mental disorders after exposure to natur al hazards

Increasing numbers of people are being affected by natural disasters due to climate change. Survivors experience higher prevalences of mental disorders than the general population, but individual responses vary considerably. Across 160 studies and almost 270,000 survivors of different natural hazards, we meta-analytically examined associations of 33 potential risk factors with posttraumatic stress disorder (PTSD), depression, and generalised anxiety disorder. Particularly peri-hazard (e.g., life threat; OR = 3.72, 95% CI 2.11-6.57), and post-hazard risk factors (e.g., low social support; OR = 3.84, 95% CI 2.41-6.12) yielded significant effects with less influence of pre-hazard factors (i.e., largest effect of prior mental health complaints: OR = 2.89; 95% CI 2.02-4.15). Several risk factors were reported sporadically and were therefore reviewed narratively (e.g., insufficient governmental support). Findings provide a clearer empirical basis for prioritizing structural and targeted interventions in disaster response and for improving resource allocation by identifying high-risk groups who may benefit from proactive outreach and integrated care strategies.

Key messages

• Post-hazard conditions such as housing instability, economic disruption, and social disintegration are particularly strong predictors of adverse mental health outcomes following natural hazards.

• Integrating mental health support into general medical and community-based settings could improve access for those who are especially vulnerable.