Seasonal Variation in Suicide in a Predominantly Caucasian Tropical/Subtropical Region of Australia

Seasonal variations in suicide were examined in a Caucasian population living relatively close to the equator. A spring/early summer peak, but no secondary autumn peak, was found for males. An autumn trough was found for females. No significant seasonal variation was found for rurality, distance from the equator, employment status, or methods of suicide. Postmortem blood alcohol levels were higher in spring & summer, possibly reflecting socialization patterns. The modest associations are consistent with the suggestion that climatic influences may produce greater variation in suicide rates where the climatic variation itself is greater. (12 refs.)