Study fails to find omega 3 benefit for depression

According to an article in this month’s Journal of the American Medical Association (JAMA),​ a randomized, double-blind trial found no evidence that combining omega-3 with the antidepressant, sertraline, is superior to sertraline plus placebo capsules for the treatment of depression in patients with major depression and established CHD.

The study states that depression is a risk factor for CHD mortality and morbidity, while low dietary intake and low serum or red blood cell levels of omega-3 fatty acids are associated with depression in patients with and without CHD.

Two omega-3 fatty acids, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) concentrate at synapses in the human brain and are essential for neuronal functioning.

Jury still out​

The authors of the JAMA​ research report that their findings are inconsistent with two previous studies that looked at depressed psychiatric patients who were otherwise medically well, and which indicated that augmentation with omega-3 fatty acids dramatically improved the efficacy of antidepressants.

A review in the British Medical Journal's Drug and Therapeutics Bulletin (DTB) claims that there is not solid scientific evidence to back the benefits reported by some observational studies and uncontrolled trials of fish oils and DHA and EPA on behaviour and learning as well as depression.

‘Despite observational evidence linking depression with reduced intake of long-chain omega-3 fatty acids, there is no convincing basis for using these nutrients as a [means of alleviating] the condition,’​ states the DTB.

The review also states that, when used in combination with antidepressant drugs, there is also only limited evidence.

Study details​

Lead researcher, Robert M Carney of Washington University School of Medicine, said that the team undertook a randomized controlled trial with 122 patients with major depression and CHD between May 2005 and December 2008.

After a two week run-in period, all patients were given 50 mg per day of sertraline and randomized in double-blind fashion to receive 2 grams per day of omega-3 acid ethyl esters (930mg of EPA and 750mg of DHA (n=62) or placebo capsules (n=60) for 10 weeks, continued the researchers.

They explained that depression was gauged via scores on the Beck Depression Inventory (BDI-II) and the Hamilton Rating Scale for Depression (HAM-D), while adherence to the medication regimen was at least 97 per cent in both groups for both medications.

Trial outcomes​

According to the research team, the results of the trial showed that the placebo and omega-3 groups did not differ at 10 weeks in regard to measurements of depression or anxiety.

There was no significant difference in rates of remission or treatment response between the two groups, added the authors.

‘Whether higher doses of EPA, DHA, or sertraline, a longer duration of treatment, or the use of omega-3 as monotherapy can improve depression in patients with stable heart disease remains to be determined,’​ concluded the authors.

Source: Journal of the American Medical Association​
Published online ahead of print: DOI: 10.1001/jama.2009.1487
Title: Omega 3 Augmentation of Sertraline in Treatment of Depression in Patients with Coronary Heart Disease: A Randomized Controlled Trial​
Authors: R. M. Carney, K. E. Freedland, E. H. Rubin; et al