The research, published in the Journal of the American College of Cardiology, was intended to test the effects of long-chain omega-3 fatty acid supplementation on omega-3 levels, depressive symptoms, and other psychosocial factors, as well as other chronic heart failure (CHF)-related functional measures.
Two interventions tested
The researchers, associated with universities and institutes in North Carolina, Pennsylvania and Virginia, put together a cohort of 108 subjects who had been diagnosed with CHF, which can arise from a number of medical conditions. They were diagnosed as depressed based on their scores on the Hamilton Depression Scale, a time-tested way to rate a patient’s status via a questionnaire administered by a clinician.
They were divided into three groups. Over the 12-week study one received a corn oil placebo while the other two received a combined EPA and DHA supplement in what appeared to be a standard 18:12 type dose, or product that was almost pure EPA. All three groups consumed capsules contained 2 grams of oil per day.
The omega-3 levels in the blood were measured by OmegaQuant, a company founded by William Harris, PhD, of the Sanford School of Medicine at the University of South Dakota. Harris was listed as a coauthor on the paper.
Omega-3 levels rose; depression scores improved
The Omega-3 Index reached 6.79% in the 2:1 EPA/DHA group, 6.32% in the EPA only group, and 4.61% in the placebo group. In those who were determined to have taken at least 70% of their capsules and finish all testing (n=80), these values were 7.32%, 7.11%, and 4.42%, respectively. This indicates that the dose (and compliance) were both adequate to significantly improve the Omega-3 Index in only three months.
The social functioning sub-score of the SF-36, a short general health survey, was significantly improved on the 2:1 EPA/DHA supplement and tended to improve with the high EPA supplement.
The study’s authors concluded: “Omega-3 supplementation resulted in significant increases in omega-3 levels in red blood cell counts, corresponding to a particular compound of omega-3. Changes in cognitive depressive symptoms and social function were in favor of the omega-3 supplementation. Further studies with larger sample sizes are necessary to confirm the benefits of omega-3 supplementation on modifying psychosocial factors for patients with CHF.”
Harris said the study’s results could have big implications for this large population group. According to the American Heart Association, the incidence of chronic heart failure is on the rise, with 6.5 million adults now living with condition (measured in teh 2011-2014 time frame), up from about 5.7 million in 2009-2012.
“About 20% of people with CHF also suffer from depression. That’s a lot,” he said.
And he said that depression is notoriously hard to treat, and changes are difficult to measure accurately.
“The fact that they found anything is encouraging. It’s very hard to treat depression. With the addition of omega-3s, if that makes even a little difference, this is very encouraging,” Harris said.
But omega-3s have shown varying results in studies with cognitive end points. Harris said more focused research is necessary, and said in particular that dividing the present study up into three groups lessened its statistical power.
“I’m not real convinced this nails down the problem by any means,” Harris said. “I wish they had tested just one intervention.”
Source: Journal of the American College of Cardiology
2018 Aug 7. pii: S2213-1779(18)30226-9. doi: 10.1016/j.jchf.2018.03.011. [Epub ahead of print]
“Long-Chain Omega-3 Fatty Acid Supplements in Depressed Heart Failure Patients: Results of the OCEAN Trial.”
Authors: Jiang W, Whellan DJ, Adams KF, et al.