Daily fish oil supplementation reduces risk of serious cardiac events, including heart attack and stroke, among patients on dialysis. The corresponding study was published in the New England Journal of Medicine.
Over 3.8 million people globally are currently receiving kidney-replacement therapy for end-stage kidney disease. Most are treated with hemodialysis. More than two-thirds of this population have cardiovascular disease, which accounts for over 75% of associated deaths. Cardiovascular mortality is 20 times higher among these patients than in the general population.
"Patients on dialysis have extremely high cardiovascular risk, and very few therapies have been shown to reduce that risk," study author, Kevan Polkinghorne, Adjunct Professor and nephrologist at Monash University, Australia, said in a press release.
"In a field where many trials have been negative, this is a significant finding,” he added.
For the study, researchers conducted a double-blind, randomized, placebo-controlled trial at 26 sites across Canada and Australia. They assigned over 1,200 adult patients receiving maintenance hemodialysis to daily supplements of either fish oil- rich in omega-3 fatty acids EPA and DHA- or corn oil, which acted as a placebo. Patients were followed for 3.5 years.
Ultimately, patients receiving fish oil were 43% less likely to experience a serious cardiovascular event than those on placebo. Events included heart attacks, strokes, cardiac-related deaths, and vascular-related amputations. Incidence of adverse events did not significantly differ between the groups.
To explain the findings, Polkinghorne indicated that dialysis patients typically have much lower levels of EPA and DHA than the general population, and that increasing these levels may explain the ‘magnitude of benefit’ observed.
“Separately and together, EPA and DHA have a range of potentially beneficial effects, including antithrombotic, antiinflammatory, antilipid, antiarrhythmic, and remodeling effects on the cardiovascular system,” wrote the researchers in their study.
Polkinghorne cautioned, however, that the findings are specific to those receiving hemodialysis for kidney failure, and that they may not apply to healthy individuals or other patient groups.
Sources: Science Daily, New England Journal of Medicine