Can life events predict first-time suicide attempts? A nationwide longitudinal study.

The prevention paradox describes circumstances in which the majority of cases with a suicide attempt come from a population of low or moderate risk, and only a few from a 'high-risk' group. The assumption is that a low base rate in combination with multiple causes makes it impossible to identify a high-risk group with all suicide attempts. The best way to study events such as first-time suicide attempts and their causes is to collect event history data. Administrative registers were used to identify a group at higher risk of suicidal behaviour within a population of six national birth cohorts (N = 300,000) born between 1980 and 1985 and followed from age 15 to 29 years. Estimation of risk parameters is based on the discrete-time logistic odds-ratio model. Lifetime prevalence was 4.5% for first-time suicide attempts. Family background and family child-rearing factors were predicative of later first-time suicide attempts. A young person's diagnosis with psychiatric or neurodevelopmental disorders (ADHD, anxiety, depression, PTSD), and being a victim of violence or sex offences contributed to the explanatory model. Contrary to the prevention paradox, results suggest that it is possible to identify a discrete high-risk group (<12%) among the population from whom two thirds of all first-time suicide attempts occur, but one third of observed suicide attempts derived from low- to moderate-risk groups. Findings confirm the need for a combined strategy of universal, targeted and indicated prevention approaches in policy development and in strategic and practice responses, and some promising prevention strategies are presented.