There has been debate over whether nonepisodic irritability is a symptom of bipolar disorder in children and adolescent (Biederman J, Biol Psychiatry 2006;60:901–902). Recently, a new study examined whether children with severe nonepisodic irritability had the same risk of manic episodes as those diagnosed with more narrowly defined bipolar disorder.
Researchers enrolled 93 children with narrowly defined bipolar disorder (BD) (mean age 12.9) and 84 children with “severe mood dysregulation” (mean age 11.6). Severe mood dysregulation (SMD) was a category created specifically to study these patients. Criteria for SMD included nonepisodic irritability (defined as frequent and impairing anger outbursts), and at least three of the following: pressured speech, agitation, insomnia, flight of ideas/racing thoughts, or distractibility.
Both groups of children were evaluated by researchers at six month intervals over a median follow up period of about 2.5 years to see if they developed hypomanic, manic, or mixed episodes. Evaluators used the structured interview instrument Kiddie Schedule for Affective Disorders—Present and Lifetime Version (KSADSPL) for all assessments.
Only one of the SMD patients (1.2%) had a hypomanic, manic, or mixed episode, versus 58 of the BD patients (62.4%) at the median follow-up of 28.7 months (Stringaris A et al., J Am Acad Child Adolesc Psychiatry 2010;49(4):397–405).
CCPR’s Take: The evaluators were not blinded to the initial diagnosis, which could have theoretically biased the results. Nonetheless, this study provides fairly strong evidence that children presenting with severe nonepisodic anger outbursts (termed SMD in the study) are unlikely to go on to develop bipolar disorder. The authors reviewed prior research showing that children with SMD are at increased risk for developing both major depression and generalized anxiety disorders. The treatment implications are that children with SMD should be considered candidates for treatment with antidepressants and stimulants rather than mood stabilizers and atypical antipschotics.