Comorbidity of attention deficit hyperactivity disorder with early- and late-onset bipolar disorder.

The relationship between attention deficit hyperactivity disorder (ADHD) and earlier age at onset of affective illness was examined in probands with a history of bipolar disorder. The authors assessed 56 adult bipolar subjects. Those with a history of childhood ADHD (N=8) were age and sex matched with bipolar subjects without a history of childhood ADHD (N=8). The age at onset of the first affective episode was lower for the subjects with bipolar disorder and a history of childhood ADHD (mean=12.1 years, SD=4.6) than for those without a history of childhood ADHD (mean=20. 0 years, SD=11.3). ADHD in children of bipolar probands might identify children at highest risk for development of bipolar disorder.