Eicosapentaenoic acid appears to be the key omega-3 fatty acid component associated with efficacy in major depressive disorder: a critique of Bloch and Hannestad and updated meta-analysis.

Abstract:

A recent meta-analysis by Bloch and Hannestad (B&H)¹ examining the efficacy of omega-3 fatty acids (ω3-FA) in major depressive disorder (MDD) claims no significant overall benefit compared with placebo; standard mean difference (SMD) 0.11 (95% CI, –0.04, 0.26) with no specific influence of eicosapentaenoic acid (EPA) dose on meta-regression analysis.

These findings contrast with those from other recent meta-analyses. As potential reasons for this disparity, we question the validity of their results on the basis of inclusion/exclusion criteria, study subgroup selection, strategy for selecting outcome measures, SMD estimates and choice of effect modifiers.