Omega-3 supplementation may reduce cardiovascular risk in patients with kidney disease
For patients with kidney disease not yet on dialysis, omega-3 fatty acid supplementation led to improvements in pulse wave velocity and serum triglyceride levels, suggesting that daily use could reduce risk for cardiovascular events.
Supplementation did not, however, impact albuminuria.
“There is interest in the possible beneficial effects that omega-3 polyunsaturated fatty acids ... could have for CKD,” Daniel Bunout, MD, of the Institute of Nutrition and Food Technology at the University of Chile, and colleagues wrote. “These fatty acids have pharmacological properties that could improve kidney function, such as anti-inflammatory actions and a reduction in blood pressure and triglyceride levels.”
Adding that previous research also suggests a benefit of omega-3 polyunsaturated fatty acids (PUFA) on albuminuria, the researchers highlighted that various studies have reached different conclusions.
“The causes of these contradictory results are numerous,” they explained. “One explanation might be limited compliance to supplementation schedules related to bad odor and secondary gastrointestinal effects of fish oil.”
Bunout and colleagues sought to add to the existing literature by assessing the impact of fatty acid supplementation on albuminuria and cardiovascular risk factors, such as pulse wave velocity (“a marker of arterial stiffness”) and triglycerides.
To limit the potential effect of “bad odor,” a highly deodorized oil containing omega-3 PUFA was used in the study.
For 3 months, 100 patients with CKD and a urine albumin excretion of at least 30 mg/g creatinine took either 3,666 mg/day of docosahexaenoic and eicosapentaenoic acids or a corn oil supplement, with the researchers noting the omega-3 PUFA supplements were “virtually indistinguishable from corn oil in terms of taste and odor.”
Results showed that at 3 months patients receiving the active supplement had significant increases in their omega-3 index (3.1% to 5.5%).
Although supplementation did not appear to improve albuminuria (defined as a 20% reduction in urine albumin), the researchers found that participants receiving omega-3 PUFA maintained their pulse wave velocity, while controls experienced an increase during follow-up. Triacylglycerol levels also decreased significantly in the omega-3 PUFA group.
Regarding adverse effects, 12 participants in the control group and 14 in omega-3 PUFA group reported mild gastrointestinal symptoms.
Elaborating on these findings, Bunout and colleagues emphasized that omega-3 fatty acid supplementation did not impact albuminuria.
“Considering that the ultimate goal of any therapeutic intervention in CKD is to delay its progression, this new study adds to the evidence that [omega-3 PUFA] do not have a role for this purpose,” they contended.
Still, they suggested the positive effects seen for the other measures are important for patients with CKD, as lessening arterial stiffness can help maintain kidney function and prevent heart failure, while reducing serum triglycerides can slow disease progression and decrease mortality rates.
“[Omega-3 PUFA] may reduce pulse wave velocity, blood pressure, and triglyceride levels in patients with CKD and thus reduce cardiovascular risk,” the researchers concluded.