Fish Oil and HDL Function in Patients on Maintenance Hemodialysis

Patients who receive maintenance hemodialysis have a very high risk of cardiovascular disease, and standard cholesterol-lowering treatments such as statins have not been shown to reduce cardiovascular events in this group. A recent clinical trial (PISCES) found that high-dose omega-3 fatty acids (fish oil) reduced cardiovascular events in hemodialysis patients, but the reason for this benefit is not understood. One possible explanation is that, in kidney failure, high-density lipoprotein (HDL) no longer works normally. This study investigates whether omega-3 fatty acid supplementation improves the function of HDL in people on maintenance hemodialysis. Forty adults on maintenance hemodialysis will take part. Each participant receives fish oil (4 g per day) for 8 weeks and also has an 8-week period without supplementation; participants are randomly assigned to the order of these two periods (crossover design), for a total of 16 weeks each. The main measure is cholesterol efflux capacity, a laboratory test of how well HDL removes cholesterol from cells. The study also examines other markers of HDL quality. This is an exploratory, mechanistic study. Its aim is to determine whether omega-3 fatty acids change HDL function and to inform the design of larger future trials.

Inclusion Criteria: * age ≥ 18 years * receiving maintenance in-center hemodialysis * able to provide written informed consent * clinically stable condition (no hospitalization within 4 weeks prior to baseline) Exclusion Criteria: * inability or unwillingness to provide informed consent * known hypersensitivity or intolerance to fish oil or n-3 PUFA-containing products * use of n-3 PUFA supplements at baseline or within the preceding 8 weeks * pregnancy * acute infection, hospitalization or major inflammatory condition at the time of baseline assessment * any condition that, in the investigator's opinion, would make participation unsafe or interfere with study participation or data interpretation * inherited lipid metabolism disorders