January 15, 2019

The November 2018 issue of the American Heart Association journal Circulation: Cardiovascular Quality and Outcomes reported findings from a secondary analysis of the Omega-3 fatty acids for the PrEvention of post-opeRative Atrial fibrillation (OPERA) study, which determined that fish oil not only failed to increase bleeding in surgery patients but also was associated with a lower risk of perioperative blood loss compared to a placebo.

“Fish oil is among the most common natural supplements for treatment of hypertriglyceridemia or prevention of cardiovascular disease,” wrote Emmanuel Akintoye of the University of Iowa and colleagues. “However, concerns about theoretical bleeding risk have led to recommendations that patients should stop taking fish oil before surgery or delay in elective procedures.”

The current research included 1,516 subjects who received a placebo or the omega-3 fatty acids eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) from fish oil during a two to five-day period prior to heart surgery. Patients received a reduced dose of EPA/DHA or placebo the morning of the surgery, which was continued until discharge from the hospital.

Perioperative bleeding, as defined by the Bleeding Academic Research Consortium, was 19% lower among those who received EPA plus DHA compared to the placebo group, and total units of blood transfused were significantly lower.

Higher plasma levels of omega-3 fatty acids the morning of the surgery corresponded to lower risks of bleeding. Patients whose omega-3 fatty acid levels placed them among the top 25% of the group had a 64% lower risk of bleeding compared to participants whose levels were among the lowest 25%.

"The researchers in this study concluded that these findings support the need to reconsider current recommendations to stop fish oil or delay procedures for people on fish oil before cardiac surgery," commented coauthor Bill Harris, PhD, who is a co-inventor of the Omega-3 Index, which evaluates red blood cell omega-3 status. "In other words, bleeding in surgery (and in normal life) is not a safety concern for omega-3 supplements."