Objectives: This study retrospectively investigated the relationship between prodromal symptoms described in the literature for pediatric bipolar disorder (BD) and the diagnosis of BD by comparing adolescents with BD to those in control and attention-deficit hyperactivity disorder (ADHD) groups.
Methods: Semi-structured interviews [Schedule for Affective Disorders and Schizophrenia for School-Age Children – Present and Lifetime version (K-SADS-PL) and Washington University in St. Louis Kiddie Schedule for Affective Disorders and Schizophrenia (WASH-U-KSADS)] and checklists (Conners’ Rating Scales and Child Behavior Checklist) identified participants (13–17 years) as either normal controls (NC; n = 28), ADHD (n = 29) or BD (n = 25). Bipolar disorder included BD I, BD II and BD not otherwise specified (NOS). Parents completed a widely used but unvalidated symptom checklist published by Papolos and Papolos (The Bipolar Child: the Definitive and Reassuring Guide to Childhood's Most Misunderstood Disorder) assessing across three developmental periods (preschool, latency, adolescence) for the presence/absence of psychiatric symptoms, many of which have been described in the literature as prodromal to the emergence of manic symptoms.
Results: While both clinical groups had more psychiatric symptoms than the NC group, more problems were reported in the ADHD group, most of which were symptoms seen as cardinal features of ADHD (e.g., being easily distracted, interrupting, having trouble concentrating). Differences were present by the latency period. Depressed mood was higher in the BD group during latency, and elated mood and fire-setting were higher in the BD group during adolescence. Results were more similar when comparing adolescents with BD only versus those with both ADHD and BD. Frequency of symptoms was comparable regardless of whether or not there was a family history of BD. Frequency of symptoms was also similar across the BD subtypes.
Conclusions: Using retrospective parent report, a cluster of prodromal psychiatric symptoms specific to BD was not identified, which both questions the utility of a widely used yet unvalidated clinical scale and encourages caution when interpreting information collected via retrospective checklists. Although these data suggest that the presence of prodromal non-specific psychiatric symptoms flags a more global risk for psychopathology, significant limitations exist when using retrospective report and, as such, further prospective research is required to investigate the progression of psychiatric symptoms across childhood disorders.