Assisted and unassisted suicide in men and women: longitudinal study of the Swiss population.

BACKGROUND In Switzerland assisted suicide is legal if no self-interest is involved. AIMS To compare the strength and direction of associations with sociodemographic factors between assisted and unassisted suicides. METHOD We calculated rates and used Cox and logistic regression models in a longitudinal study of the Swiss population. RESULTS Analyses were based on 5 004 403 people, 1301 assisted and 5708 unassisted suicides from 2003 to 2008. The rate of unassisted suicides was higher in men than in women, rates of assisted suicides were similar in men and women. Higher education was positively associated with assisted suicide, but negatively with unassisted. Living alone, having no children and no religious affiliation were associated with higher rates of both. CONCLUSIONS Some situations that indicate greater vulnerability such as living alone were associated with both assisted and unassisted suicide. Among the terminally ill, women were more likely to choose assisted suicide, whereas men died more often by unassisted suicide.