Efficacy and acceptability of mood stabilisers in the treatment of acute bipolar depression: systematic review

BACKGROUND: Although people with bipolar disorder spend more time in a depressed than manic state, little evidence is available to guide the treatment of acute bipolar depression. AIMS: To compare the efficacy, acceptability and safety of mood stabiliser monotherapy with combination and antidepressant treatment in adults with acute bipolar depression. METHOD: Systematic review and meta-analysis of randomised, double-blind controlled trials. RESULTS: Eighteen studies with a total 4105 participants were analysed. Mood stabiliser monotherapy was associated with increased rates of response (relative risk (RR) = 1.30, 95% CI 1.16-1.44, number needed to treat (NNT) = 10, 95% CI 7-18) and remission (RR = 1.51, 95% CI 1.27-1.79, NNT = 8, 95% CI 5-14) relative to placebo. Combination therapy was not statistically superior to monotherapy. Weight gain, switching and suicide rates did not differ between groups. No differences were found between individual medications or drug classes for any outcome. CONCLUSIONS: Mood stabilisers are moderately efficacious for acute bipolar depression. Extant studies are few and limited by high rates of discontinuation and short duration. Further study of existing and novel agents is required.