Weather and suicide: the present state of knowledge on the association of meteorological factors with suicidal behaviour

Objective: To review the available literature on the association between daily and longer-term weather data and the incidence of attempted and completed suicide. Method: A computerized search supplemented by a cross-check of the references sections of the thereby identified papers was performed. Results: A total of 27 studies looking for a relationship between attempted or completed suicide and weather or climate data were found. Most of the papers reported a statistical association of suicidal acts with at least one weather factor. However, the results are not conclusive and in part contradictory. Conclusion: Possibly due to the high variance in methodological approaches of the studies it is not possible to identify a specific weather condition associated with a generally higher risk for suicide. Weather and seasonal effects may interact with each other. Environmental effects on brain function and weather-related interactions of people may be involved in the occurrence of suicidal behaviour.