Youths with BP spectrum disorders showed a continuum of BP symptom severity from subsyndromal to full syndromal with frequent mood fluctuations. Results of this study provide preliminary validation for BP-NOS.

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.

Objective-To assess the longitudinal course of youth with bipolar spectrum disorders.Methods-413 youth (7-17 years) with bipolar-I (n=244), bipolar-II (n=28), and bipolar NotOtherwise-Specified (NOS) (n=141) were recruited mainly from outpatient clinics at the University of Pittsburgh, Brown, and UCLA. Symptoms were ascertained retrospectively on average every 9.4 months for 4 years using the Longitudinal Interval Follow-up Evaluation. Rates and time to recovery and recurrence and week-by-week symptomatic status were analyzed.Results-Approximately 2.5 years after onset of their index episode, 81.5% of subjects fully recovered, but 1.5 years later 62.5% had a syndromal recurrence, particularly depression. One-third of the subjects had one syndromal recurrence and 30% ≥ 2 syndromal recurrences. The polarity of the index episode predicted the polarity of subsequent episodes. Subjects were symptomatic during 60% of follow-up time, particularly with subsyndromal symptoms of depression and mixed-polarity, with numerous changes in mood polarity. Manic symptomatology, especially syndromal, was less frequent and bipolar-II was mainly manifested by depressive symptoms. Forty-percent of subjects had syndromal and/or subsyndromal symptoms during 75% of follow-up period. During 17% of follow-up time subjects, especially those with bipolar-I, experienced psychosis. Twenty-five percent of bipolar-II subjects converted into bipolar-I and 38% of bipolar-NOS converted into bipolar -I/II. Early-onset, bipolar-NOS, long duration, low socio-economic status, and family history of mood disorders were associated with poorer outcomes.Conclusions-Bipolar spectrum disorder in youth is an episodic disorder characterized by subsyndromal and, less frequently, syndromal episodes with mainly depressive and mixed symptoms and rapid mood changes.

Objective To determine the rate of diagnostic conversion from an operationalized diagnosis of Bipolar Disorder Not Otherwise Specified (BP-NOS) to Bipolar I or Bipolar II Disorders (BP-I/II) in youth over prospective follow-up and to identify factors associated with conversion. Method Subjects were 140 children and adolescents recruited from clinical referrals or advertisement who met operationalized criteria for BP-NOS at intake and participated in at least one follow-up evaluation (91% of initial cohort). Diagnoses were assessed at follow-up interviews using the Longitudinal Interval Follow-Up Evaluation. The mean duration of follow-up was 5 years and the mean interval between assessments was 8.2 months. Results Diagnostic conversion to BP-I/II occurred in 63 subjects (45%): 32 (23%) to BP-I (9 of whom had initially converted to BP-II) and 31 to only BP-II (22%). Median time from intake to conversion was 58 weeks. First or second-degree family history of mania or hypomania was the strongest baseline predictor of diagnostic conversion (p=.006). Over follow-up, conversion was associated with greater intensity of hypomanic symptoms and with greater exposure to specialized, intensive outpatient psychosocial treatments. There was no association between conversion and exposure to treatment with particular medication classes. Conclusions Children and adolescents referred with mood symptoms that meet operationalized criteria for BP-NOS, particularly those with a family history of BP, frequently progress to BP-I or BP-II disorders. Efforts to identify these youth and effectively intervene may have the potential to curtail the progression of mood disorders in this high-risk population.