ADHD in a school sample of Brazilian adolescents: A study of prevalence, comorbid conditions, and impairments

Objective: To evaluate the prevalence, comorbid conditions, and impairments of attention-deficit/hyperactivity disorder (ADHD) among young adolescents in Porto Alegre, Brazil. Method: 1,013 students aged 12 to 14 years were e valuated at 64 state schools, using a screening instrument based on the 18 DSM-IV ADHD symptoms. All positive screened students (n = 99) and a random subset of negative screened subjects (n = 92) had a psychiatric evaluation carried out within a hospital setting or at home. Results: The prevalence o f ADHD was estimated to be 5.8% (95% confidence interval = 3.2-10.6), and t he comorbidity with other disruptive behavior disorders was high (47.8%). Y ouths with ADHD (n = 23) had significantly higher rates of school repetitio ns, suspensions, and expulsions (p <.01) than controls (n = 168). No associ ation was identified between ADHD and alcohol, marijuana, and inhalent use. Conclusion: The results extend to adolescents well-documented findings in children, indicating that ADHD is quite prevalent in early adolescence and affected youths are at high risk for impairment and dysfunction in multiple domains.