Abstract
OBJECTIVE: Co-morbid diagnoses, such as disruptive behavior disorders (DBDs) and high levels of aggression, are extremely common among youth with pediatric bipolar disorder (PBD) and may interfere with treatment response; however, they have rarely been examined as predictors of response to pharmacotherapy. The current study examines co-morbid DBD and aggression prospectively as predictors of pharmacotherapy outcome, as well as potential moderators of response to a specific medication (risperidone vs. divalproex), among children with PBD. METHODS: Data are from a prospective 6-week double-blind, placebo-controlled, randomized outpatient medication treatment trial of risperidone versus divalproex for manic episodes in 65 children 8-18 with PBD. Outcome measures were administered at pretest, post-test, and weekly during the 6 weeks of treatment. Mixed-effects regression models were used to examine pharmacotherapy response. RESULTS: Results indicated that youth with co-morbid DBD experienced greater improvement in manic symptoms in response to risperidone versus divalproex, whereas youth with non-co-morbid DBD experienced similar trajectories of symptom improvement in both medication groups. In addition, the non-DBD group experienced greater improvement in global functioning over time as compared with youth with co-morbid-DBD, and this gap increased over the course of treatment. Results also indicated that high-aggression youth experienced worse global functioning by end treatment versus low-aggression youth. CONCLUSIONS: In conclusion, a co-morbid diagnosis of DBD and/or high levels of aggressive symptoms in youth with PBD may be important clinical predictors of variation in treatment response to pharmacotherapy. These findings may help researchers and clinicians develop tailored treatment approaches that optimize symptom and functional outcomes.