Doctors often recommend omega-3 fatty acids to help patients lower their cholesterol levels and improve heart health. These omega-3 fatty acids can come from oily fish such as salmon and mackerel or from dietary supplements that often contain a combination of the acids eicosapentaenoic acid acid (EPA) and docosahexaenoic acid (given).
New research from the Intermountain Healthcare Heart Institute in Salt Lake City has found that higher blood levels of EPA alone lower the risk of serious cardiac events and patient death, while DHA mitigates EPA’s cardiovascular benefits. Higher DHA levels at each EPA level worsened health outcomes.
The results of the Intermountain study, which examined nearly 1,000 patients over a period of 10 years, will be presented virtually on Monday, May 17, at the American College of Cardiology 2021 scientific session.
“The advice to take omega-3s for the benefit of your heart is widespread, but previous studies have shown that science does not confirm this for every single omega-3 system,” said Viet T. Le, MPAS , PA, researcher and cardiovascular physician assistant at the Intermountain Heart Institute and principal investigator on the study. “Our results show that not all omega-3s are created equal, and that EPA and DHA together, as often found in dietary supplements, can negate the benefits that patients and their doctors are hoping for.”
In this study, Intermountain researchers used the INSPIRE registry, an Intermountain Healthcare database launched in 1993 containing more than 35,000 blood samples from nearly 25,000 patients.
Through INSPIRE, the researchers identified 987 patients who had their first documented coronary angiographic study at Intermountain Healthcare between 1994 and 2012. From these blood samples, the circulating EPA and DHA levels in their blood were measured. The researchers then followed these patients for 10 years looking for serious cardiac side effects including heart attack, stroke, heart failure that required hospitalization or death.
They found that patients with the highest EPA levels had a lower risk of serious cardiac events. When evaluating how EPA and DHA affect each other, they found that higher levels of DHA diminished the benefits of EPA. In particular, they also found that patients with higher levels of DHA than EPA are at greater risk of heart problems.
Le said these results raise further concerns about the use of combined EPA / DHA, particularly through supplements.
“Based on these and other findings, we can still tell our patients to eat foods rich in omega-3s, but we shouldn’t recommend them in pill form as dietary supplements or even as combined prescription products (EPA + DHA),” said he. “Our data reinforce the results of the recent REDUCE-IT (2018) study that EPA prescription products reduce cardiac events.”
Meeting: American College of Cardiology 2021
Other members of the research team are: Stacey Knight; Kirk Knowlton; Raymond McCubrey; Jeramie D. Watrous; Mahan Najhawan; Khoi Dao; Tami Bair, Benjamin Horne; J. Brent Muhlestein; Donald Lappe; Madisyn Taylor; John Nelson; John Carlquist; Mohit Jain; and Jeffrey Anderson.