Natural disasters and suicidality in Australia: a systematic review

Area of Science:

• Environmental Health
• Mental Health Research
• Public Health Surveillance

Background:

• Natural disasters pose significant threats to population well-being.
• Understanding the mental health impacts of disasters is crucial for effective public health interventions.
• Previous research on natural disasters and suicidal behaviours in Australia requires systematic synthesis.

Purpose of the Study:

• To systematically review Australian evidence on the association between natural disaster exposure and suicidal behaviours.
• To examine suicidal ideation, suicide attempts, and suicide mortality in relation to events like droughts, floods, and bushfires.
• To synthesize findings on the nuanced relationship between disaster types and mental health outcomes.

Main Methods:

• Systematic review conducted adhering to PRISMA and SwiMS guidelines, with a pre-registered protocol.
• Searched databases in May 2026 for Australian observational studies on natural disasters and suicidal behaviours.
• Assessed risk of bias using Joanna Briggs Institute tools and performed narrative synthesis of findings.

Main Results:

• Twelve studies were included, showing mixed evidence for suicide mortality but consistent links between disaster exposure and increased suicidal ideation and self-harm.
• Stronger associations were observed with prolonged drought, heat exposure, displacement, and repeated disaster events, often with dose-response patterns.
• Most studies had moderate risk of bias, primarily due to exposure misclassification and confounding variables.

Conclusions:

• Natural disasters in Australia are more consistently linked to non-fatal suicidal behaviours than to suicide mortality.
• Post-disaster mental health strategies must include ongoing monitoring of suicidal ideation and self-harm.
• Evidence suggests a need for sustained mental health support following natural disasters, extending beyond the acute phase.