Adolescent antisocial behavior and substance use: longitudinal analyses.

This study explores how antisocial behavior among adolescents at age 14 is related longitudinally to their daily smoking, heavy alcohol use, and illicit drug use (hashish and amphetamines) at age 17. The sample of 9th graders (n = 1293) attending compulsory schools in Reykjavik, Iceland participated in the study and in the follow-up 3 years later. The focus is on a subgroup of 17-year-old adolescents who had not experimented with cigarette smoking, alcohol consumption, or illicit drug use at age 14. Even after eliminating from the study those who had experimented with smoking at age 14 and those whose peers smoked, the adolescents who showed more signs of antisocial behavior at age 14 were more likely to smoke daily at age 17. Similar findings were revealed for illicit drug use at age 17. Further, with regard to alcohol use, adolescents who had not experimented with alcohol but showed indications of antisocial behavior at age 14 were more likely to drink heavily at each episode at age 17 if their parents drank.