People suffering from major depressive disorder who also have high inflammation levels may benefit from taking omega-3 fatty acid EPA (eicosapentataenoic acid), new research from Emory University suggests.

In a randomized trial, 155 participants were given either two capsules containing EPA-enriched mix or a placebo, or four capsules of a docosahexaenoic acid-enriched mix or four placebo capsules for eight weeks. All participants had been previously diagnosed with major depressive disorder.

EPA was found to be effective for a group of patients who had high levels of at least one of four markers of inflammation in their blood. Docosahexaenoic acid (DHA) was not effective for this group of patients.

The researchers call the finding a proof-of-concept for the idea that anti-inflammatory treatments can be effective in subgroups of patients with depression. They published their findings in the journal Molecular Psychiatry.

Mark Hyman Rapaport, principal investigator and professor and chair of the psychiatry and behavioral sciences department at Emory University School of Medicine, said this:

“The diversity of both symptoms and underlying variations of the progression of major depressive disorder confounds the development of targeted treatments for the disease.”

Depression and Obesity

This goes along with earlier studies showing that an anti-inflammatory drug infliximab can be effective in some patients with treatment-resistant depression, specifically those with high levels of inflammation.

The results back up the thinking that anti-inflammatory therapy is only beneficial as a treatment of inflammation-driven major depressive disorder, and is ineffective and potentially harmful for individuals whose depression is due to a different physiological disturbance, the researchers say.

They have preliminary data suggesting that obese patients with depression are more likely to have high markers of inflammation, and might benefit from anti-inflammatory drugs.

In future studies, they are going to replicate their preliminary findings and extend them by investigating the influence of other important biological measures and clinical characteristics.


M H Rapaport, A A Nierenberg, P J Schettler, B Kinkead, A Cardoos, R Walker and D Mischoulon Inflammation as a predictive biomarker for response to omega-3 fatty acids in major depressive disorder: a proof-of-concept study Molecular Psychiatry , (24 March 2015) | doi:10.1038/mp.2015.22

For future updates, subscribe via Newsletter here or Twitter