Elizabeth L. Hart

Developmental change in attention-deficit hyperactivity disorder in boys: A four-year longitudinal study

One hundred six clinic-referred boys meeting criteria for DSM-III-R attention-deficit hyperactivity disorder (ADHD) (mean age 9.4 years) were assessed annually for 4 years using structured interviews of multiple informants. Hyperactivity—impulsivity symptoms declined with increasing age, but inattention symptoms did not. Rather, inattention declined only from the first to the second assessment and remained stable thereafter in boys of all ages. The rate of decline in hyperactivity—impulsivity symptoms was independent of the amount and type of treatment received. Boys who still met criteria for ADHD in Years 3 and 4 were significantly younger, more hyperactive—impulsive, and more likely to exhibit conduct disorder in Year 1 than boys who no longer met criteria in Years 3 and 4.

Issues of taxonomy and comorbidity in the development of conduct disorder

A developmental approach to the classification of antisocial behavior is necessary for two reasons. First, although the continuity of antisocial behavior is strong for many individuals, the topography of antisocial behavior changes during the course of development. Second, antisocial behavior apparently develops in at least two separate pathways — child-onset versus adolescent-onset — that differ markedly regarding types of antisocial behavior displayed, persistence, and perhaps etiology. The development of antisocial behavior must also be understood within the context of co-occurring disorders and conditions. Comorbid attention-deficit hyperactivity disorder appears to be associated with greater aggression and a worse prognosis, and comorbid academic underachievement is also associated with a negative course. Emerging evidence also suggests that comorbid anxiety disorder is associated with level of aggression, but the direction of the correlation appears to differ at different ages. In all, full understanding of conduct disorder requires developmentally sensitive classification as well as consideration of comorbid conditions.

Validity of DSM-IV subtypes of conduct disorder based on age of onset

OBJECTIVE To present data from the DSM-IV field trials that led to the distinction between subtypes of conduct disorder (CD) that emerge in childhood or adolescence. In addition, data from a household sample were used to attempt to cross-validate these findings. METHOD Differences between youths who met criteria for the two subtypes of CD were examined in the field trials sample of 440 youths aged 4 through 17 years and in a household sample of 1,285 youths aged 9 through 17 years. RESULTS In both samples, there was a steep decline in aggression occurring around an age of onset of 10 years, but the number of nonaggressive behaviors was unrelated to the age of onset of CD. In the field trials sample, youths who met criteria for the adolescent-onset type were more likely to be girls, less likely to meet criteria for oppositional defiant disorder, and less likely to have a family history of antisocial behavior than the childhood-onset type, but these latter findings were not confirmed in the household sample. CONCLUSIONS The DSM-IV approach to subtyping CD distinguishes subgroups that differ markedly in level of physical aggression. The advantages of a developmental approach to subtyping are discussed.

Anxiety, Inhibition, and Conduct Disorder in Children: II. Relation to Salivary Cortisol

The relation of symptoms of conduct disorder (CD) and anxiety to salivary cortisol was explored in 67 clinic-referred boys aged 8 to 13 years. Children with anxiety disorder had higher levels of cortisol, but this main effect was qualified by a significant CD x anxiety disorder interaction. Consistent with Grays biological model of the behavioral inhibition system (BIS), children with both CD and anxiety disorder had higher levels of salivary cortisol than children with CD without comorbid anxiety disorder. In the absence of CD, however, anxiety disorder was not clearly associated with higher cortisol. This result suggests that cortisol may be a useful biological marker of arousal associated with BIS activity in children with CD.