Lithium augmentation in antidepressant-resistant patients. A quantitative analysis.

A quantitative analysis was used to examine the efficacy of lithium augmentation in the acute treatment of depressed patients resistant to a standard trial of an antidepressant. Effect sizes were measured by the odds ratio using the Mantel-Haenszel method. Only controlled trials were included in order to minimise bias in method. A highly statistically significant effect for lithium augmentation was found, the pooled odds ratio being 0.146 and its 95% confidence interval 0.05-0.44 (i.e. the odds of remaining ill are reduced by between 56% and 95% with the use of lithium treatment). While these results support the case for lithium augmentation in treatment-resistant depression, there remains considerable uncertainty over the duration of treatment necessary to see and sustain the treatment response.