[Alcohol, tobacco, and other drug use by teenage students in a city in Southern Brazil].

This study analyzes alcohol, tobacco, and other drug use by seventh-graders in municipal schools in the city of Gravataí, Rio Grande do Sul State, Brazil, and associated factors. A cross-sectional school survey was conducted in a representative random sample of 1,170 seventh-graders from municipal schools. The bivariate Cox regression model, modified for cross-sectional studies, was used to evaluate associations between specific factors and outcomes. Prevalence rates for lifetime consumption of alcohol, tobacco, and other drugs were 60.7%, 16.9%, and 2.4%, respectively. Consumption rates in the previous 30 days were: alcohol, 33%; tobacco, 4.4%; and other drugs, 0.6%. The study showed an association with substance use by family and friends. Prevalence of tobacco and alcohol use during the previous 30 days was associated with feelings of sadness, loneliness, insomnia, and suicidal ideation. Use of other drugs was associated with loneliness and suicidal ideation.