Adjunctive Docosahexaenoic Acid in Residual Symptoms of Depression and Anxiety

Abstract

Abstract Objective The aim of the study is to examine the efficacy of omega-3 fatty acid as an adjunct to ongoing pharmacological treatments in patients with residual symptoms of depression and anxiety. Methods/Procedures This randomized, double-blind, placebo-controlled, cross-over trial was conducted at a single private practice site. Participants were drawn from patients attending the practice. Patients meeting criteria had a 4-week run-in period where they continued to receive their prescribed medications and omega-3 supplements. Depression and anxiety ratings were assessed at recruitment and completion of the run-in phase. Patients were randomized to receive an omega-3 supplement (Neurospark) or placebo once daily for 8 weeks then crossed over to the alternative treatment. At the end of the double-blind, cross-over phase, patients received the supplement and were assessed after a 4-week run-out phase. Depression and anxiety symptoms were assessed using the Hamilton scales. Efficacy of treatment was assessed using a linear mixed model analysis with time, order of treatment, diagnosis, and their interaction as factors. Depression and anxiety scales were analyzed as independent measures. Results The study enrolled 47 patients (mean [SD] age, 46.1 [11.2] years; [59.6%] male). Depression scores did not significantly change across assessments (P > 0.1); there was no effect of order of treatment (P > 0.1) or an interaction between time, order of treatment, and psychiatric diagnosis (P > 0.1). Anxiety scores were similarly unchanged across treatment visits and order of treatment, and there was no interaction between time, order of treatment, and psychiatric diagnosis. Conclusions Omega-3 fatty acid supplementation did not significantly alter residual symptoms in this group of patients.