Alcohol, cannabis and other drugs and subsequent suicide ideation and attempt among young Mexicans

Objective: To report results from a follow-up study of alcohol, cannabis and other drugs on suicidal behavior. Method: We estimated prospective associations of substance use as a risk factor for incident suicide ideation and attempt, from a follow-up conducted in 2013 (n = 1071) of the original Mexican Adolescent Mental Health Survey conducted in 2005. Results: Cannabis use before age 15 (ideation risk ratio (RR) = 3.97; 95% confidence interval (CI) = 1.43-11.03; attempt RR = 5.23; 95% CI = 1.17-23.32), early onset of DSM-IV drug use disorder (DUD) among cannabis users (ideation RR = 3.30; 95% CI = 1.11-9.84; attempt RR = 4.14; 95% CI = 1.28-13.36), high frequency of cannabis use (RR for attempts = 4.60; 1.03-20.60) and recent DSM-IV-DUD among cannabis users (RR for attempts = 4.74; 1.09-20.57) increased the RR. For "other drug use", significant results were found among those with high frequency use of other drugs such that they had a higher RR of suicide attempt (5.04; 1.03-24.64). For alcohol, only those who initiated alcohol before age 15 had higher RRs of suicide attempt (1.79; 1.00-3.20). Discussion: Those who used cannabis at an early age, early onset of DSM-IV-DUD, and those with heavy cannabis use and recent DSM-IV-DUD among cannabis users in the last 12-months had increased risk of suicide ideation and attempt. Drugs other than cannabis showed some of these associations, but to a lesser degree. Prevention of substance use and treatment of those already engaged in drug use, by decreasing suicide ideation and attempt, may help to prevent suicide in Mexico. (C) 2017 Elsevier Ltd. All rights reserved.