A daily fish oil supplement may significantly reduce serious cardiovascular events in people receiving dialysis for kidney failure.
The findings come from a major international clinical trial—Protection Against Incidences of Serious Cardiovascular Events Study with Daily Fish Oil Supplement in Patients on Dialysis, or PISCES—led by investigators in Canada and Australia, who presented their findings at the American Society of Nephrology (ASN) 2025 Kidney Week (6–9 November, Houston, USA). The full paper was published this year in the New England Journal of Medicine.
The PISCES trial involved 1,228 participants across 26 dialysis sites across the two countries. Participants who received 4g per day of fish oil, containing the natural active ingredients EPA and DHA, experienced a 43% lower rate of serious cardiovascular events compared with the placebo group. These events included heart attack, stroke, cardiac death and vascular-related amputations.
“While other heart protective medications have been shown to be beneficial in the general population, they haven’t consistently reduced cardiovascular events in the haemodialysis population,” said Charmaine Lok (University of Toronto, Toronto, Canada), the lead investigator of the trial. “Fish oil supplementation is a simple, well-tolerated intervention that could have a meaningful impact.”
Kevan Polkinghorne, nephrologist at Monash Health (Melbourne, Australia), served as the lead investigator for the Australian arm. “Patients on dialysis have extremely high cardiovascular risk, and very few therapies have been shown to reduce that risk,” he said. “In a field where many trials have been negative, this is a significant finding.
“Dialysis patients typically have much lower levels of EPA and DHA than the general population. This may help explain the magnitude of benefit observed in this group.”
Polkinghorne noted that the findings are specific to people receiving haemodialysis for kidney failure and should not be applied to healthy individuals or other patient groups.
