Irritability without elation in a large bipolar youth sample: frequency and clinical description.

OBJECTIVE: To determine whether some children with bipolar disorder (BP) manifest irritability without elation and whether these children differ on sociodemographic, phenotypic, and familial features from those who have elation and no irritability and from those who have both.

METHOD: Three hundred sixty-one youths with BP recruited into the three-site Course and Outcome of Bipolar Illness in Youth study were assessed at baseline and for most severe past symptoms using standardized semistructured interviews. Bipolar disorder subtype was identified, and frequency and severity of manic symptoms were quantified. The subjects were required to have episodic mood disturbance to be diagnosed with BP. The sample was then reclassified and compared based on the most severe lifetime manic episode into three subgroups: elated only, irritable only, and both elated and irritable.

RESULTS: Irritable-only and elated-only subgroups constituted 10% and 15% of the sample, respectively. Except for the irritable-only subjects being significantly younger than the other two subgroups, there were no other between-group sociodemographic differences. There were no significant between-group differences in the BP subtype, rate of psychiatric comorbidities, severity of illness, duration of illness, and family history of mania in first- or second-degree relatives and other psychiatric disorders in first-degree relatives, with the exception of depression and alcohol abuse occurring more frequently in the irritability-only subgroup. The elated-only group had higher scores on most DSM-IV mania criterion B items.

CONCLUSIONS: The results of this study support the DSM-IV A criteria for mania in youths. Irritable-only mania exists, particularly in younger children, but similar to elated-only mania, it occurs infrequently. The fact that the irritable-only subgroup has similar clinical characteristics and family histories of BP, as compared with subgroups with predominant elation, provides support for continuing to consider episodic irritability in the diagnosis of pediatric BP.