Metabolic syndrome in patients enrolled in a clinical trial of aripiprazole in the maintenance treatment of bipolar I disorder: a post hoc analysis of a randomized, double-blind, placebo-controlled trial

OBJECTIVE

To compare the effects of maintenance treatment with aripiprazole or placebo on the incidence of metabolic syndrome in bipolar disorder.

METHOD

Patients with DSM-IV bipolar I disorder were stabilized on aripiprazole therapy for 6-18 weeks prior to double-blind random assignment to aripiprazole or placebo for 26 weeks. The rate of metabolic syndrome in each group was calculated at maintenance phase baseline (randomization) and endpoint for evaluable patients using a last-observation-carried-forward (LOCF) approach. Metabolic syndrome was defined using the National Cholesterol Education Program Adult Treatment Panel III criteria. The study was conducted from March 2000 to June 2003 at 76 centers in Argentina, Mexico, and the United States.

RESULTS

At entry into the maintenance phase, 45/125 patients (36.0%) overall met criteria for metabolic syndrome. Mean changes in the 5 components of metabolic syndrome (waist circumference, triglyceride levels, high-density lipoprotein cholesterol level, blood pressure, and glucose level) from baseline to week 26 were small except for a meaningful reduction in triglycerides (placebo -18.9 mg/dL; aripiprazole -11.5 mg/dL). By the end of the maintenance phase (endpoint, LOCF), 5/18 placebo-treated patients (27.8%) and 4/14 aripiprazole-treated patients (28.6%) no longer met metabolic syndrome criteria. The proportion of patients with metabolic syndrome was similar in the placebo and aripiprazole groups at both baseline and week 26. There were no significant changes in any of the individual components of metabolic syndrome between aripiprazole- and placebo-treated patients during maintenance phase treatment.

CONCLUSIONS

The prevalence of metabolic syndrome in patients with bipolar disorder is higher than that commonly reported in the general population. The effect of 26 weeks of treatment with aripiprazole on the incidence of metabolic syndrome and its components was similar to placebo.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00036348.

A 6-month, double-blind, maintenance trial of lithium monotherapy versus the combination of lithium and divalproex for rapid-cycling bipolar disorder and Co-occurring substance abuse or dependence

OBJECTIVE

To assess whether combination treatment with lithium and divalproex is more effective than lithium monotherapy in prolonging the time to mood episode recurrence in patients with rapid-cycling bipolar disorder and comorbid substance abuse and/or dependence.

METHOD

A 6-month, double-blind, parallel-group comparison was carried out in patients who met DSM-IV criteria for (1) bipolar I or II disorder; (2) alcohol, cannabis, or cocaine abuse within the last 3 months or dependence within the last 6 months; (3) rapid cycling during the 12 months preceding study entry; and (4) a history of at least 1 manic, hypomanic, or mixed episode within 3 months of study entry and who had demonstrated a persistent bimodal response to combined treatment with lithium and divalproex. Subjects were randomly assigned to remain on combination treatment or to discontinue divalproex and remain on lithium monotherapy. The study was conducted at an outpatient mood disorders program between October 1997 and October 2006.

RESULTS

Of 149 patients enrolled into the open-label acute stabilization phase, 79% discontinued prematurely (poor adherence: 42%, nonresponse: 25%, intolerable side effects: 10%). Of 31 patients (21%) randomly assigned to double-blind maintenance treatment, 55% (N = 17) relapsed (24% [N = 4] into depression and 76% [N = 13] into a manic/hypomanic/mixed episode), 26% (N = 8) completed the study, and 19% (N = 6) were poorly adherent or exited prematurely. The median time to recurrence of a new mood episode was 15.9 weeks for patients receiving lithium monotherapy and 17.8 weeks for patients receiving the combination of lithium and divalproex (not significant). The rate of relapse into a mood episode for those receiving lithium monotherapy or the combination of lithium and divalproex was 56% (N = 9) and 53% (N = 8), respectively. The rate of depressive relapse in both arms was 13% (N = 2), while the rate of relapse into a manic, hypomanic, or mixed episode was 44% (N = 7) for lithium monotherapy and 40% (N = 6) for the combination of lithium and divalproex.

CONCLUSION

A small subgroup of patients in this study stabilized after 6 months of treatment with lithium plus divalproex. Of those who did, the addition of divalproex to lithium conferred no additional prophylactic benefit over lithium alone. Although depression is regarded as the hallmark of rapid-cycling bipolar disorder in general, these data suggest that recurrent episodes of mania tend to be more common in presentations accompanied by comorbid substance use.

TRIAL REGISTRATION

clinical trials.gov Identifier: NCT00194129.