Is augmentation with folate effective for major depressive disorder?

INTRODUCTION: Antidepressant treatment does not lead to a satisfactory response in a significant proportion of patients with depression. It has been postulated that co-administration of pharmacologically standardized nutrients (nutraceuticals), such as folate, would potentiate the effect of antidepressants.

METHODS: To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS: We identified four systematic reviews including nine studies overall, of which eight were randomized trials. We concluded augmentation with folate for the treatment of major depressive disorder probably results in little or no difference in depressive symptoms. It would be interesting to evaluate the effects of specific presentation forms of folate or in population with objective folate deficit.