Context: Children and adolescents who present with manic symptoms frequently do not meet the full DSM-IV criteria for bipolar I disorder (BP-I).
Objective: To assess the clinical presentation and family history of children and adolescents with BP-I, bipolar II disorder (BP-II), and bipolar disorder not otherwise specified (BP-NOS).
Design: Subjects and their primary caretaker were assessed by semistructured interview, and family psychiatric history was obtained from interview of the primary caretaker.
Setting: Outpatient and inpatient units at 3 university centers.
Participants: A total of 438 children and adolescents (mean +/- SD age, 12.7 +/- 3.2 years) with BP-I (n = 255), BP-II (n = 30), or BP-NOS (n = 153).
Main outcome measures: Lifetime psychiatric history and family history of psychiatric disorders.
Results: Youth with BP-NOS were not diagnosed as having BP-I primarily because they did not meet the DSM-IV duration criteria for a manic or mixed episode. There were no significant differences among the BP-I and BP-NOS groups in age of onset, duration of illness, lifetime rates of comorbid diagnoses, suicidal ideation and major depression, family history, and the types of manic symptoms that were present during the most serious lifetime episode. Compared with youth with BP-NOS, subjects with BP-I had more severe manic symptoms, greater overall functional impairment, and higher rates of hospitalization, psychosis, and suicide attempts. Elevated mood was present in 81.9% of subjects with BP-NOS and 91.8% of subjects with BP-I. Subjects with BP-II had higher rates of comorbid anxiety disorders compared with the other 2 groups and had less functional impairment and lower rates of psychiatric hospitalization than the subjects with BP-I.
Conclusions: Children and adolescents with BP-II and BP-NOS have a phenotype that is on a continuum with that of youth with BP-I. Elevated mood is a common feature of youth with BP-spectrum illness.