Self harm with and without suicidal intent at age 16 years were associated with later substance use at 18 years (table 2). Harmful alcohol use and illicit drug use outcomes were more common in those with suicidal self harm than with non-suicidal self harm; however, strong evidence for a difference between the self harm groups was found only for problem cannabis use (odds ratio 2.32, 95% confidence interval 1.31 to 4.10) and smoking regularly (1.42, 1.00 to 2.00). After adjustment for socioeconomic position and symptoms of depression at age 13 years, there was little attenuation in results.
