Pediatric Bipolar Disorder: Subtype Trend and Impact of Behavioral Comorbidities

The diagnosis of pediatric bipolar disorder (PBD) has increased dramatically in community-treated youth in the past 20 years. No previous study has assessed the trend in PBD subtype diagnoses or the impact of clinician-reported behavioral comorbidities (BC) on psychotropic medication prescribing patterns. This study aims: (1) to characterize national trends in PBD visits in relation to PBD subtypes; and (2) to assess differences in socio-demographic PBD subtype diagnostic patterns and psychotropic medications prescribed in PBD visits with and without behavioral comorbidities (w/w/o BC). PBD visits for 1999-2010 from the National Ambulatory Medical Care Survey (NAMCS) data were assessed using population-weighted chi-square and logistic regression analyses. While PBD visit rates were stable across 12 years, the proportional shift of subtype diagnosis from Bipolar I (89.0%) in 1999-2002 to Bipolar Not Otherwise Specified (NOS) (74.1%) in 2007-2010 was notable. Compared with PBD without behavioral comorbidities (w/o BC), PBD visits w/BC had greater proportions of the bipolar-NOS subtype, more males, 2-14-year-olds, and more publicly-insured visits. The prescription of antipsychotics (60% vs. 61%) was common in PBD visits regardless of the presence of behavioral comorbidities. Stimulants were the predominant class prescribed for PBD visits with BC (67.8% vs. 9.4%). Antidepressants were significantly greater in PBD visits without BC (41.6% vs. 21.0%). Overall one-third of PBD youth visits were prescribed antipsychotics concomitant with other psychotropic classes. Behavioral conditions accompanying PBD visits were prominent, suggesting the need for monitoring and evaluating the outcomes of complex medication regimens in community populations.