Studies of adolescents and young adults who had been diagnosed with attention deficit hyperactivity disorder (ADHD) in childhood have shown that conduct problems, arrest records, poor academic histories and continuation of ADHD symptoms are common. Only two prospective, controlled studies of psychiatric status in adulthood have been performed. Mannuzza and associates prospectively followed boys of average intelligence with ADHD to gain further understanding of the course of this disorder.

The study subjects were referred to a child psychiatric clinic by teachers at an average age of 7.3 years. Eighty-five of the 104 subjects were interviewed at a mean age of 24.1 years. These probands were compared with 73 persons recruited from a nonpsychiatric clinic population. Interviewers were blinded to group status. The duration of follow-up ranged from 15 to 21 years.

The probands were significantly older and of lower social class than the comparison subjects. One third of the probands versus one fifth of the comparison subjects had ongoing mental disorders at the time of adult follow-up. The most common diagnoses in the probands were antisocial personality disorder and nonalcohol substance abuse.

Marijuana was abused by all of the probands with nonalcohol substance use disorder and in two of the three comparison subjects who had nonalcohol substance problems. Sixty percent of the probands with antisocial personality disorder versus 13 percent of those without antisocial personality disorder had comorbid substance use disorders. Only 4 percent of the probands (and none of the comparison subjects) had the full ADHD syndrome at follow-up, and no subject reported clinically impairing symptoms in the absence of the full syndrome. No evidence indicated that ADHD probands were at greater risk for having a current mood or anxiety disorder in adulthood.

The authors conclude that most cases of childhood ADHD remit by adulthood. They note that the study group was not entirely representative of children with ADHD, since other studies show that 30 to 50 percent of these children have comorbid conduct disorders. The authors view the absence of conduct disorder in the probands as a positive feature, noting that it is critical to examine the natural history of ADHD independently of the well-known consequences of conduct disorder, since 50 to 70 percent of children with ADHD do not have conduct disorder. It is relevant to note that even when conduct disorder is present, most affected children do not retain the disorder into adulthood.