Abstract

Background and objectives: Marine-derived omega-3 polyunsaturated fatty acids (n-3 PUFA) have been shown to exert protective effects on all-cause and cardiovascular (CV) mortality in the general population. In renal transplant recipients (RTR) all-cause and CV mortality is high but the effect of n-3 PUFA intake on long-term outcome is unclear. We investigated whether marine-derived n-3 PUFA intake is associated with risk of all-cause and CV mortality in a large cohort of RTR. Methods: Intake of Eicosapentaenoic acid plus Docosahexaenoic acid (EPA-DHA) was assessed using a validated Food Frequency Questionnaire. Cox-Proportional Hazards Regression analyses were performed to evaluate the associations of EPA-DHA intake with all-cause and CV mortality. Results: We included 627 RTR (age 53 ± 13 years, 56% male). EPA-DHA intake was 102 [interquartile range: 42-216] mg/day. During median follow-up of 5.4 years, 130 (21.0%) RTR died, with 52 (8.3%) due to CV causes. EPA-DHA intake was associated with lower risk of all-cause mortality (Hazard Ratio (HR) 0.85; 95% confidence interval (95%CI) 0.75-0.97, P = 0.02), independent of potential confounders. The HR for the association of EPA-DHA intake with CV mortality was of similar magnitude, but did not reach significance (HR 0.83, 95%CI 0.68-1.02, P = 0.08). The association of EPA-DHA intake with mortality was significantly modified by age (P = 0.03) and smoking status (P = 0.01), with lower risk for all-cause and CV mortality particularly in the older (≥ 63 years old) (HR 0.75; 95%CI 0.61-0.92, P = 0.01; and 0.68; 95%CI 0.48-0.95, P = 0.02 respectively) and non-smokers (HR 0.80; 95%CI 0.68-0.93, P = 0.01; and 0.74; 95%CI 0.56-0.98, P = 0.04, respectively) subgroups of RTR. Conclusions: Higher marine-derived n-3 PUFA intake was associated with lower risk of all-cause and CV mortality in RTR. Strongest associations were present in elderly and non-smoking RTR. Our study adds further evidence to the plea for EPA-DHA supplementation in RTR, particularly in subgroups of this population.