High-Dose Fish Oil May Raise Odds for A-Fib in Heart Patients

By Amy Norton
HealthDay Reporter

MONDAY, May perhaps 3, 2021 (HealthDay Information) — Many people today choose fish oil to defend their coronary heart, but a new study implies that prescription versions may possibly increase the chance of a widespread coronary heart rhythm problem.

At challenge are prescription-strength omega-3 fatty acids, which are by natural means located in fish oil. The prescription drugs are usually recommended to people today with incredibly significant triglycerides, a variety of blood excess fat joined to amplified chance of coronary heart attack and stroke.

According to the American Coronary heart Association, prescription omega-3s can lower triglycerides by twenty% to thirty% in most people today.

But the prescription drugs are also controversial, mainly because their ultimate advantages for the coronary heart are unclear.

Now the new study — an analysis of 5 previous medical trials — implies warning is in get. Over-all, trial people supplied omega-3s ended up above a person-3rd extra most likely to build atrial fibrillation (a-fib) than those supplied a placebo. The fish oil doses taken ranged from .84 grams to 4 grams for every day.


A-fib is a widespread coronary heart rhythm problem, or arrhythmia, in which the heart’s upper chambers get started to quiver chaotically rather of contracting correctly.

A-fib is not promptly daily life-threatening, but it really is “not benign,” possibly, stated Dave Dixon, a person of the scientists on the study and an associate professor at Virginia Commonwealth College (VCU), in Richmond.

Around time, Dixon stated, a-fib can direct to complications like coronary heart failure or stroke.

Particularly how prescription-strength omega-3 could lead to a-fib is unclear, according to Dixon.

Nonetheless, the amplified chance was fairly consistent across the trials — extra consistent, in truth, than coronary heart advantages ended up, stated co-researcher Salvatore Carbone, an assistant professor at VCU.

In all 5 trials, there ended up extra a-fib scenarios among omega-3 people than placebo people, while the change in chance was not statistically significant in all reports.

But when the scientists pooled the success of all 5 trials, there was a obvious end result: Omega-3 people ended up 37% extra most likely to build a-fib than placebo people ended up.

In contrast, only a person trial showed that an omega-3 solution could lower the hazards of other coronary heart problems.


In that trial, dubbed Lessen-IT, people applying a solution identified as Vascepa (icosapent ethyl) noticed their chance of “cardiovascular events” drop by 25%. That incorporated coronary heart attack, stroke and death from cardiovascular results in.

Even in that study, while, a-fib chance rose among omega-3 buyers, by 35%.

Why has only a person trial located coronary heart advantages? Yet again, it really is not nevertheless obvious, Dixon stated.

But, he added, Vascepa is distinct from the fish oil products and solutions analyzed in the other trials. It is made up of only a person omega-3, identified as EPA, although the other products and solutions have a combination of EPA and DHA.

And in the Lessen-IT trial, Dixon stated, increased concentrations of EPA in patients’ blood correlated to lower cardiovascular hazards.

That hints, he stated, that concentrating on EPA could possibly be “the way to go in the long term.” But the conflicting conclusions on the advantages of omega-3s — together with the potential chance of a-fib — emphasize the have to have for extra reports, the scientists stated.

The analysis was posted April 29 in the European Coronary heart Journal — Cardiovascular Pharmacotherapy.


Findings on the coronary heart advantages of fish oil have certainly been “inconsistent,” stated Linda Van Horn, a member of the coronary heart association’s nutrition committee and a professor at Northwestern College Feinberg School of Medicine, in Chicago.

And that incorporates reduced-dose, above-the-counter fish oil dietary supplements.

“There are minimal and inconsistent facts pertaining to the profit or chance of getting fish oil dietary supplements,” Van Horn stated.

So the coronary heart association endorses having two servings of fish a week rather. Van Horn stated that fatty fish, these as salmon, trout, albacore tuna and herring, are the best sources of omega-3s.

The trials in the present-day analysis analyzed prescription-strength omega-3s. But Carbone stated he would be cautious about above-the-counter fish oil dietary supplements, as well.

“We never know if above-the-counter products and solutions could have these similar consequences,” he stated.

Around-the-counter fish oil is regarded as a dietary supplement, so it is not controlled by the U.S. Meals and Drug Administration as a drug would be, Dixon pointed out.

Both of those he and Carbone stated it really is best to communicate to a medical professional or pharmacist ahead of starting up any fish oil solution and that people today on prescription omega-3s should really converse with their medical professional ahead of halting.


More information

Harvard Clinical School has extra on fish oil and coronary heart overall health.

Sources: Salvatore Carbone, PhD, assistant professor, kinesiology and overall health sciences, Virginia Commonwealth College, Richmond, Va. Dave L. Dixon, PharmD, associate professor, ambulatory care, and vice-chair, medical solutions, division of pharmacotherapy and outcomes science, Virginia Commonwealth College, Richmond, Va. Linda Van Horn, PhD, RD, professor and main, nutrition division, division of preventive medicine, Northwestern College Feinberg School of Medicine, Chicago, and member, Nutrition Committee, American Coronary heart Association, Dallas European Coronary heart Journal—Cardiovascular Pharmacotherapy, April 29, 2021, on-line