The main aim of this study was to examine the age-dependent persistence of ADHD in boys transitioning from adolescence into early adulthood attending to different definitions of persistence. We conducted a 10-year follow-up study (mean follow-up time=11 years) of 110 boys with ADHD and 105 non-ADHD controls. Both groups were 6-17 years of age at ascertainment. ADHD was considered persistent at follow-up if subjects met full or subthreshold (more than half of the symptoms required for a full diagnosis) DSM-IV diagnostic criteria, failed to attain functional remission (GAF score ≤60), or were receiving treatment for ADHD. While 65% of children with ADHD no longer met full DSM-IV criteria for ADHD at the 10-year follow-up, 78% of subjects met at least one of our definitions of persistence. Persistence as described above was associated with more psychiatric comorbidity, more familiality with mood disorders, and higher levels of educational and interpersonal impairments than controls. This 10-year longitudinal follow-up study shows that the majority of ADHD boys experience persistent symptoms and functional impairments into early adulthood. Persistence of ADHD is associated with greater psychiatric comorbidity, familiality and functional impairments.

The objective of the study was to systematically examine patterns of psychiatric comorbidity in referred youth with autism spectrum disorders (ASD) including autistic disorder and pervasive developmental disorder not otherwise specified. Consecutively referred children and adolescents to a pediatric psychopharmacology program were assessed with structured diagnostic interview and measures of psychosocial functioning. Comparisons were made between those youth satisfying diagnostic criteria for ASD and age and sex matched youth without ASD referred to the same clinical program. 9.3% (217/2323) of the referred youth (age range: 3-17 years) met DSM-III-R criteria for ASD. ASD youth suffered from significantly higher number of comorbid disorders than comparisons (6.4 ± 2.7 vs. 5.2 ± 2.9; p < 0.001). Ninety-five percent of the youth with ASD had three or more comorbid psychiatric disorders and 74% had five or more comorbid disorders. ASD youth were also more functionally impaired and required extra-assistance in school and therapeutic interventions at higher rates than age and sex matched non-ASD referred youth. Youth with ASD have high levels of psychiatric comorbidity and dysfunction comparable to the referred population of youth without ASD. These findings emphasize the heavy burden of psychiatric comorbidity afflicting youth with ASD and may be important targets for intervention.