Suicidal ideation in a random community sample: attributable risk due to depression and psychosocial and traumatic events.

OBJECTIVE: To determine the attributable risk for suicidal ideation of depression and psychosocial and traumatic events in a random and representative population.
METHOD: Data were gathered from a random and representative sample of 2501 South Australians. Suicidal ideation and clinical depression were determined by the general health questionnaire (GHQ-28) and the short-form health survey (SF-12) respectively, and information regarding psychosocial stressors and traumatic events was collated. These data were subjected to univariate and multivariate analyses to determine the population-attributable risks for suicidal ideation.
RESULTS: Overall, 5.6% of men and 5.3% of women had suicidal ideation. Univariate analyses demonstrated a significant attributable risk for suicidal ideation for depression and the majority of the psychosocial and traumatic events. Multivariate analysis demonstrated that clinical depression remained significantly associated with suicidal ideation, with a population-attributable risk of 46.9%. Because of the small number of people in the population who experience both suicidal ideation and specific events, multivariate analysis could not be applied to individual events. However, even when the psychosocial events were summed, they no longer remained significantly associated with suicidal ideation, whereas the summation of traumatic events remained significant, with a population-attributable risk of 38.0%.
CONCLUSIONS: These results confirm the importance of traumatic events as significant factors in contributing to suicidal ideation. However, of even greater importance is that they indicate, unequivocally, the magnitude of the contribution of clinical depression to suicidal ideation, with the population-attributable risk of depression indicating that elimination of mood disorders would reduce suicidal ideation by up to 46.9%.