Objective: To ascertain the prevalence of mood disorders among consecutively evaluated prepubertal children presenting for the treatment of attention-deficit/hyperactivity disorder (ADHD) in a community mental health clinic.

Method: 104 children received systematic assessments designed to identify individuals meeting the DSM-IV criteria for major depressive disorder (MDD), mania, and ADHD. "Standard" and "modified" criteria for mania were employed. Modified criteria, in an effort to minimize false-positive diagnoses of mania, required the presence of euphoria and/or flight of ideas. A child meeting the criteria for MDD or either set of criteria for mania was categorized as having a mood disorder. Mood disorders in first-degree relatives were assessed using a systematic interview. Data were gathered from 2000 to 2002.

Results: Sixty-two children (59.6%) had a mood disorder. Compared with those who did not have a mood disorder, they were 3.3 times more likely (54.8% vs. 16.7%) to have a family history of any affective disorder (p < .0001) and 18.3 times more likely (43.5% vs. 2.4%) to have a family history of bipolar disorder (p < .0001). Twenty (32.3%) of the children with and none without a mood disorder had psychotic features (p < .0001). Compared with those meeting only the standard criteria for mania, those meeting the modified criteria were 9.1 times more likely (69.8% vs. 7.7%) to have a family history of an affective disorder (p < .0001) and 7.3 times more likely (55.8% vs. 7.7%) to have a family history of bipolar disorder (p = .002).

Conclusion: Children who presumably have ADHD often have unrecognized affective illness. Our findings support the view that children meeting the modified criteria for mania have veritable bipolar disorder. These findings, which were derived in the course of delivering routine clinical services in a community mental health clinic, are consistent with those obtained in research settings suggesting that children presenting with ADHD often have occult mood disorders, especially unrecognized bipolarity. We suggest that clinicians encountering children with prominent features of ADHD inquire about the presence of euphoria and flight of ideas. We submit that the presence of these "classic" manifestations of mania strongly suggests the presence of occult bipolarity, even if course of illness otherwise markedly deviates from "classic" descriptions.