Preventing relapse in bipolar disorder

Bipolar disorder is a life long condition characterized by an irregular pattern of acute episodes separated by periods of full or partial remission. While keeping patients well after a remission is a primary therapeutic goal, relapse rates have remained high despite the wide spread use of lithium. There are now well powered double blind placebo controlled studies demonstrating the efficacy of lithium [1], valproate [2], lamotrigine [3], olanzapine [4–6], and aripiprazole for one or more outcome measure related to prophylaxis.

Understanding the design of these clinical trials can help interpretation of the results for clinical practice. Traditionally the maintenance phase of treatment for patients with mood disorder was conceptualized as therapeutic target separate from the acute and continuation phase. Most randomized clinical trials demonstrating prophylactic treatment benefit, however, use an "enriched design". Rather than randomizing already recovered patients to start study medications, enriched designs begin with subjects who have met criteria for acute response while already exposed to the study drug.

The success of the enriched study design supports continuation of successful acute treatment and/or the integration of potential maintenance phase treatments into the acute phase management plan.