Common mental disorders in adolescents: a population based cross-sectional study.

OBJECTIVE To assess the prevalence and the factors associated with common mental disorders among adolescents in Pelotas, a southern Brazilian city. METHOD A population based cross-sectional study was carried out in the urban area of Pelotas. Multi-stage sampling was used to obtain a sample of adolescents aged between 15 and 18 years. Adolescents were interviewed using a self-report confidential questionnaire. The presence of common mental disorders was assessed using the Self-Reporting Questionnaire 20 (SRQ-20). Multivariate analysis was carried out using the Poisson regression with a robust adjustment of variance and control for design effect. RESULTS Nine hundred and sixty adolescents were interviewed. The prevalence of common mental disorders was 28.8%. Adolescents aged 17 years showed prevalence of 1.37 (95% CI 1.06-1.78) times greater than the 15 year olds. Adolescents whose mothers had between 5 and 8 years of schooling had a prevalence 1.42 (95% CI 1.01-1.51) times greater than those whose mothers had more than 8 years of schooling. Smoking and sedentary behavior were also associated with an increased prevalence of common mental disorders. Those who were dissatisfied with their body image showed a prevalence of 1.47 (95% CI 1.07-2.02). CONCLUSIONS Maternal schooling, tobacco smoking, sedentary behavior and body image dissatisfaction were factors associated with the presence of common mental disorders.