Omega-3 fatty acid supplementation does nothing for youths with depression

In the treatment of children and adolescents with major depressive disorder (MDD), adjunctive supplementation with omega-3 fatty acid does not appear to significantly improve outcomes compared with placebo, according to study.

A total of 257 youths with moderate-to-severe MDD (mean age 15.7 years, 73.2 percent female), with a mean Children’s Depression Rating Scale–Revised (CDRS-R) score of 58.5 at baseline, were included in the study.

The participants were randomly assigned to receive supplementation with omega-3 fatty acids at 1.5 g/d (1 g of eicosapentaenoic acid [EPA] and 0.5 g of docosahexaenoic acid [DHA], 2:1 ratio) (n=129) or medium-chain triglyceride placebo (n=128) in combination with standardized psychotherapy. Antidepressant use was permitted per national guidelines. All participants were followed-up for 36 weeks.

The primary outcome was the trajectory of CDRS-R scores accounting for dropout or initiation of off-trial antidepressant therapy. Secondary outcomes included response (≥30-percent reduction in CDRS-R scores), remission (CDRS-R score ≤28), self-rated depression, quality of life, suicidality, and safety.

Mean CDRS-R scores decreased similarly in both the omega-3 and placebo groups at 12 weeks (45.93 vs 46.08) and at 36 weeks (36.50 vs 36.83). CDRS-R score trajectories did not significantly differ between the two groups (mean difference, 0.77 points, 95 percent confidence interval [CI], –1.39 to 2.93; p=0.49; hazard ratio for time to dropout, 1.22, 95 percent CI, 0.83–1.79; p=0.32).

Response occurred in 31.2 percent of participants in the omega-3 group and in 39.1 percent in the placebo group at 12 weeks. By week 36, remission had been documented in 31.9 percent and 41.1 percent of participants in the respective treatment groups. Suicidality and other secondary measures improved without between-group differences.

Treatment adherence in the omega-3 group was confirmed, with the EPA plus DHA levels expressed by the ω-3 index increasing by a mean of 4.33 percent at 12 weeks and 4.88 percent at 36 weeks.

A total of 76 serious adverse events (SAEs) were documented in 97 participants, with 45 occurring in the omega-3 group and 31 in the placebo group. These SAEs included 28 suicide attempts, none of which resulted in deaths or permanent disabilities. None of these were judged to be causally related to the study medication.