Suicide in adolescents: findings from the Swiss National cohort.

Suicide in adolescents is the second most common cause of death in this age group and an important public health problem. We examined sociodemographic factors associated with suicide in Swiss adolescents and analysed time trends in youth suicide in the Swiss National Cohort (SNC). The SNC is a longitudinal study of the whole Swiss resident population, based on linkage of census and mortality records. We identified suicides in adolescents aged 10-18 years from 1991 to 2013. A total of 2.396 million adolescents were included and 592 suicides were recorded, corresponding to a rate of 3.7 per 100,000 [95% confidence interval (CI) 3.4-4.0]. Rates increased with age from 0.0 per 100,000 at age 10 years to 14.8 per 100,000 (95% CI 12.6-17.5) at 18 years in boys, and from 0.0 to 5.4 per 100,000 (4.1-7.2) in girls. Being a boy, living in a single parent household, being an only or middle-born child, and living in rural regions were factors associated with a higher rate of suicide. Hanging was the most common method in boys, and railway suicides were most frequent in girls. There was no clear evidence for an increase or decrease over calendar time. We conclude that familial and socioeconomic factors including type of household, birth order and urbanity are associated with youth suicide in Switzerland. These factors should be considered when designing prevention programmes for youth suicide.