Early determinants of attention and hyperactivity problems in adolescents: the 11-year follow-up of the 1993 Pelotas (Brazil) birth cohort study.

The aim of this study was to assess early determinants of attention and hyperactivity problems in adolescents. In 1993, all hospital births in the city of Pelotas, Rio Grande do Sul State, Brazil, were monitored and mothers were interviewed (N = 5,249). At 11 years of age, 4,423 mothers answered the Strengths and Difficulties Questionnaire (SDQ) in order to evaluate attention and hyperactivity problems in the adolescents. Crude and adjusted prevalence ratios were calculated using Poisson regression. Prevalence of attention and hyperactivity problems was 19.9%. Factors associated with the outcome in the adjusted analysis were: male gender, low family income, smoking during pregnancy, minor psychiatric disorders in the mother, and history of child's behavioral/emotional problems at four years of age. Early life events impacted attention and hyperactivity problems in adolescence. Risk factors for attention and hyperactivity problems found in this study were similar to those reported in other cultures.