Latest maintenance data on lithium in bipolar disorder.

Although lithium is generally considered to be the gold standard for maintenance therapy in bipolar disorder, evidence of its efficacy has rested on only a small number of adequately designed studies. Results from the lamotrigine bipolar trials, which included lithium as an active comparator, will substantially increase confidence in long-term lithium treatment. In a meta-analysis of these data, lithium was significantly more effective than placebo in preventing relapse in patients with bipolar disorder (relative risk [RR] 0.65; 95% confidence interval [CI] 0.50, 0.84). Furthermore, lithium had significant efficacy against manic relapse (RR 0.61; 95% CI 0.39, 0.95), with a less substantial, not statistically significant, effect against depressive relapse (RR 0.72; 95% CI 0.49, 1.07). Factors such as disease subtype, likelihood of adherence to treatment regimen, tolerability, and dose uncertainty should be considered in the selection of lithium maintenance therapy.