September 29, 2023
The National Longitudinal Survey of Children and Youth is a prospective cohort of Canadian children followed from childhood to early adulthood. It is considered nationally representative, except for children living on First Nations (indigenous) reserves, in institutions, and in remote regions. Keep in mind that suicide rates among indigenous youth are way higher than in the general population.
The initial cohort included 8,698 participants aged 7- 11 years, of which 6,465 had to be excluded for lack of answers to questions on suicide attempts, leaving 2,233 participants. Again, by comparison with the excluded group, these participants were less likely to be from higher-risk backgrounds, including having a mother who did not complete high school or coming from low-income families.
The share of adolescents who attempted suicide in the previous year increased from 3.6% at ages 12-13 years to 5.6% at ages 14-15 years, then gradually declined to 1% of young adults at ages 22-23 years.
The overwhelming majority (96%)reported never attempting suicide. One in fifty (2%) reported suicide attempts limited to adolescence, and another one in fifty reported suicide attempts persisting into adulthood.
The study team performed a multivariable regression model examining the contributions of sex and ten risk factors, including various psychiatric disorders, for suicidality. One of those risk factors was ADHD, split into two subcategories: symptoms at 10-11 years, and symptoms at 12-13 years. Those in the former group were twice as likely -for each standard deviation increase in symptoms - as those without such symptoms to report suicide attempts persisting into adulthood versus never attempted. But they were no more likely to report adolescence-limited attempts versus never-attempted, or attempts persisting into adulthood versus adolescence-limited. Furthermore, there were no significant associations between ADHD symptoms at 12-13 years and any of the three foregoing categories.
The authors acknowledged, "despite the large sample size, the number of individuals who attempted suicide was low, limiting the statistical power ..."
Marie-Claude Geoffroy, Massimiliano Orri, Alain Girard, LeaC. Perret, and Gustavo Turecki, "Trajectories of suicide attempts from early adolescence to emerging adulthood: prospective 11-year follow-up of a Canadian cohort," Psychological Medicine (2020), https://doi.org/10.1017/S0033291720000732.