RESUMO
BACKGROUND: This study evaluates the long-term efficacy of aripiprazole compared to placebo in children with bipolar disorders. METHOD: Outpatients aged 4 to 9 years meeting DSM-IV criteria for a bipolar disorder (I, II, not otherwise specified, cyclothymia) were eligible to receive up to 16 weeks of open-label treatment with aripiprazole (phase 1). Patients were randomized into the 72-week double-blind phase of the study once they met a priori response criteria for stabilization (phase 2). During phase 2, patients either remained on their current aripiprazole regimen or began a double-blind taper with aripiprazole discontinued and switched to placebo. The primary outcome measure for phase 2 was time to discontinuation due to a mood event. RESULTS: Patients were recruited between May 2004 and November 2008. Following phase 1, in which 96 patients received aripiprazole, 30 patients (mean age = 7.1 years) were randomly assigned to continue aripiprazole and 30 patients (mean age = 6.7 years) were randomly assigned to placebo. The mean (SD) dose of aripiprazole prior to randomization for these patients was 6.4 (2.1) mg/d. Patients randomly assigned to aripiprazole were enrolled significantly longer until time to study discontinuation due to a mood event (6.14 median weeks, SE ± 11.88 weeks; P = .005) and discontinuation for any reason (including mood events) (4.00 median weeks, SE ± 3.91 weeks; P = .003) than those randomly assigned to placebo (mood event, 2.29 median weeks, SE ± 0.38 weeks; any reason, 2.00 median weeks, SE ± 0.31 weeks). Regardless of random assignment, both the aripiprazole and placebo groups showed substantial rates of withdrawal from maintenance treatment over the initial 4 weeks (15/30 [50%] for aripiprazole; 27/30 [90%] for placebo), suggesting a possible nocebo effect (ie, knowledge of possibly switching from active medication to placebo increasing concern about relapse). The most frequently reported adverse events during double-blind aripiprazole therapy included stomach pain (n = 10, 33%), increased appetite (n = 9, 30%), and headaches (n = 9, 30%). CONCLUSIONS: Despite the possibility of a nocebo effect, these results suggest that aripiprazole may be superior to placebo in the long-term treatment of pediatric patients following stabilization with open-label aripiprazole. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00194077.