A PILOT FAMILY STUDY OF CHILDHOOD-ONSET MANIA

Objective: To investigate the familiar association of attention-deficit hyperactivity disorder (ADHD) and bipolar disorder (BPD) among the first-degree relatives of children with comorbid ADHD and BPD. Background: In contrast to a growing body of literature on childhood non-bipolar depression, little is known about childhood BPD. Among the explanations accounting for the lack of recognition and identification of these children is the symptomatic overlap of BPD with ADHD. Family-genetic studies provide information external to the clinical picture and thus are uniquely suited to clarify such issues of diagnostic comorbidity. Method: Structured diagnostic interviews were used to obtain DSM-III-R psychiatric diagnoses on first-degree relatives (n = 46) of referred children (aged less than or equal to 12 years) satisfying diagnostic criteria for mania using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Epidemiologic Version (n = 16). For comparison, diagnostic information on the first-degree relatives of non-bipolar ADHD children and control children was examined. Results: The results show high rates of comorbidity between BPD and ADHD in children and high rates of both BPD and ADHD in the first-degree relatives of these children. Moreover, ADHD and BPD cosegregated among the relatives of children with BPD. Conclusions: These findings, which are consistent with the authors' prior study of children with ADHD, provide family-genetic evidence for the validity of BPD and ADHD when they exist comorbidly in children. Moreover, they suggest that the comorbid condition of ADHD+BPD may be a distinct nosological entity.