The Cumulative Incidence of Self-Reported Suicide-Related Thoughts and Attempts in Young Canadians [2018]

To estimate the cumulative incidence of self-reported suicide-related thoughts (SRTs) and suicide attempts (SAs) in males and females from 11 to 25 years of age in Canada.

A cohort study was conducted by linking cycles 2 to 8 from the National Longitudinal Survey of Children and Youth, a representative survey of Canadians aged 11 to 25 years conducted from 1996 to 2009. The 11- to 25-year cumulative incidence of self-reported SRTs and SAs (with suicidal intent) was estimated in males and females using a novel application of a counting process approach to account for discontinuous risk intervals between survey cycles.

The risk of SRTs was 29% (95% confidence interval [CI], 26% to 31%) in females and 19% (95% CI, 16% to 23%) in males. The risk of SAs was 16% (95% CI, 14% to 19%) in females and 7% (95% CI, 6% to 8%) in males. Over 70% of SRTs and SAs first occur between 11 and 16 years of age and 30% between 11 and 13 years of age, respectively.

The risk of SRTs and SAs is high in young Canadians, with most events first occurring in early to mid-adolescence and possibly earlier. Females are at a higher risk compared to males. This research underscores the need for better longitudinal surveillance of SRTs and SAs in the population. A counting process framework could be useful for future research using existing longitudinal surveys suffering from design limitations relating to gaps in respondent follow-up. Furthermore, these findings have implications for younger SRT and SA risk management by clinicians and earlier implementation of suicide prevention programs.

Sarah M. Goodday, PhD, Susan Bondy, PhD, Rinku Sutradhar, PhD, Hilary K. Brown, PhD, Anne Rhodes, PhD
The Canadian Journal of Psychiatry, July 5, 2018