Leo Sher, M.D.

A research report, “Does cannabis use in adolescence predict self-harm or suicide? Results from a Finnish Birth-Cohort Study” has been published in Acta Psychiatrica Scandinavica online ahead of print (1). The Northern Finland Birth Cohort 1986 with linkage to nationwide register data was used to study the association of self-reported cannabis use at age 15-16 years and self-harm and suicide death until age 33 (until year 2018), based on register information.

In all, 6582 (49.2 % male) were included in the analysis, and 377 adolescents (5.7%) reported any cannabis use until the age of 15-16 years. Based on register information, 79 (55.7 % male) had visited in health care services due to self-harm, and 22 (90.1 % male) had died by suicide. Adolescent cannabis use was associated with self-harm. The association between cannabis use and self-harm remained statistically significant after adjusting for sex, psychiatric disorders at baseline, frequent alcohol intoxications, other illicit drug use, and parental psychiatric disorders. The association of cannabis use with suicide did not reach statistical significance.

The authors have noted that not having more detailed information on self-harm and suicidal behavior can be considered as a limitation of the study. When using register-based information, it is not possible to differentiate between non-suicidal self-injury and suicide attempt. The authors have also noted that using register-based information rather than self-report of self-harm may lead to underreporting.

Reference

1. Alexander D, Niemelä S, Scott JG, Salom C, Emily H, Miettunen J, Anni-Emilia A, Mustonen A. Does cannabis use in adolescence predict self-harm or suicide? Results from a Finnish Birth-Cohort Study. Acta Psychiatr Scand. 2021 Nov 10. doi: 10.1111/acps.13384. Epub ahead of print.