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Article Abstract

The phenomenology of pediatric bipolar disorder is a controversial topic in the field of child psychiatry.The first National Institute of Mental Health-funded study in the field, Phenomenology andCourse of Pediatric Bipolar Disorders, selected a conservative phenotype for credibility in a contentiousfield. To address the problems of differentiation of mania from attention-deficit/hyperactivitydisorder (ADHD) and of the ubiquitous manifestation of irritability across child psychiatry diagnoses,a prepubertal and early adolescent bipolar I disorder phenotype (PEA-BP) was defined by DSM-IVbipolar I disorder (manic or mixed phase) with elation and/or grandiosity as one criterion. This criterionavoided diagnosing mania by symptoms that overlapped with those of ADHD (e.g., hyperactivity,distractibility) and ensured that subjects had at least 1 of the cardinal symptoms of mania (i.e., elationor grandiosity). This definition was analogous to the requirement that DSM-IV major depressive disorderinclude at least 1 of the cardinal symptoms of depression (i.e., sad mood or anhedonia). Subjectswere 93 children with a mean ± SD age of 10.9 ± 2.6 years. Validation of the phenotype was shownaccording to Robins and Guze criteria: unique symptoms that did not overlap with those of ADHD,stability of the diagnosis (did not become ADHD or other disorders on follow-up) as shown by a4-year prospective longitudinal study, significantly higher familial aggregation of bipolar disorder inrelatives of PEA-BP versus ADHD and healthy control probands, and family-based linkage disequilibriumof the brain-derived neurotrophic factor Val66 allele in PEA-BP probands. Furthermore,PEA-BP resembled the most severe adult bipolar disorder, manifested by a chronic, ultradian-cycling,mixed manic, psychotic course. A conservatively defined child mania phenotype met the Robins andGuze criteria for establishing diagnostic validity in psychiatric illness. Continuities between PEA-BPand adult bipolar disorder and relationships of PEA-BP to other descriptions of child mania arediscussed.