Fish Oil Supplementation Won't Stop Atrial Fibrillation Recurrence

As researchers look for alternatives to conventional atrial fibrillation (AF) therapies, some have proposed that supplementation with long-chain n-3 polyunsaturated fatty acids (PUFAs) may be a cost-effective intervention, due to its potential antiarrhythmic properties.

While previous studies examining PUFA-rich fish oil’s role in AF have been inconclusive, a new study published in the October 2014 issue of the Journal of the American College of Cardiology has indicated that high doses of the supplementation fails to prevent the condition.

Led by the Montreal Heart Institute, the Multi-center Study to Evaluate the Effect of N-3 Fatty Acids [OMEGA-3] on Arrhythmia Recurrence in Atrial Fibrillation (AFFORD) trial assessed the influence of high-dose fish oil in AF recurrence, inflammation, and oxidative stress. To do so, the study authors enrolled 337 patients with AF who were not prescribed any conventional antiarrhythmic therapy. The participants were randomized to either 4 g/day of fish oil or placebo and then followed for up to 16 months.

At the conclusion of the trial, the researchers discovered that the rate of AF recurrence was similar in both arms of the study, with 63% to 64% of patients experiencing an additional event. Furthermore, fish oil supplementation did not reduce inflammation or oxidative stress markers. The investigators noted that oxidative stress has been proposed as a cause of AF, which might explain why fish oil did not reduce AF recurrence in their research.

Ultimately, the study provided the first definitive evidence that fish oil has no role in rhythm-control management in AF.

"What is well-known and should be recommended to prevent heart disease and reduce blood pressure is a Mediterranean-type diet rich in natural omega-3 fats and other nutrients, including fresh fruits and veggies, legumes, olive oil, while lowering intake of red meat, trans fats, and saturated fats,” said lead investigator Anil Nigam, MD, a cardiologist at the Montreal Heart Institute Research Center and associate professor of medicine at the University of Montreal, in a press release. “We believe that such a strategy might also be beneficial for the treatment of AF, although more studies are required.”