OBJECTIVE:
The effects of supplementation of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on prevalence and severity of depression were evaluated in patients after a myocardial infarction.

METHOD:
A cross-sectional evaluation (posttest-only design) within the prospective, randomized, controlled, multicenter OMEGA trial was performed in patients after myocardial infarction at 12 months' follow-up (N = 2,081; age, mean = 64 years; men, 76.7%; women, 21.8%) from April 2005 to June 2007. Patients received supplementation with ethyl esters 90 (460-mg EPA and 380-mg DHA) or placebo for 12 months. Depression was assessed with the Beck Depression Inventory-II (BDI-II); a BDI-II cutoff score of ≥ 14 was used as diagnosis of depression.

RESULTS:
When the total population was evaluated, no effects of EPA/DHA supplementation on depressive symptoms according to BDI-II score (mean [SD]) could be demonstrated: EPA/DHA (n = 1,046), 7.1 (6.9); placebo (n = 1,035), 7.1 (7.0); P = .7. The post hoc analyses of depressed patients with and without antidepressants revealed a tendency toward an antidepressant effect in patients with EPA/DHA supplementation as monotherapy: EPA/DHA (n = 125), 19.4 (5.8); placebo (n = 113), 19.9 (5.1); P = .07. However, in depressed patients with EPA/DHA supplementation as adjunctive to conventional antidepressants, a clinically relevant antidepressant effect was demonstrated: EPA/DHA (n = 33), 20.9 (7.1); placebo (n = 29), 24.9 (8.5); P < .05.

CONCLUSIONS:
EPA/DHA supplementation in the total sample of patients after myocardial infarction had no effect on depressive symptoms. The clinically relevant antidepressant effect in the subgroup of depressed patients with EPA/DHA supplementation as adjunctive to conventional antidepressants that was revealed in the post hoc analysis might provide a basis for a controlled, prospective trial of omega-3 augmentation of antidepressants in patients after myocardial infarction.