Omega‐3 PUFA plasma and red blood cell status in chronic hemodialysis patients

Abstract

Omega-3 (n-3) polyunsaturated fatty acid (PUFA) levels have been inversely associated with cardiovascular (CVD) mortality. Chronic hemodialysis patients (HP), who suffer from extremely high rates of CVD, may be at risk for inadequate n-3 consumption. This study was designed to determine n-3 status in a hemodialysis population by comparing their PUFA levels to those of a healthy control group. Fasting plasma and red blood cell (RBC) fatty acid levels were measured in 75 HP and 25 control subjects (CS). The HP were more likely to have diabetes mellitus (43% vs. 20%), hypertension (91% vs. 36%), and less formal education. CS had significantly higher levels of plasma eicosapentaenoic acid (EPA) (mean wt % ± SD) (0.42 ± 0.13 vs. 0.35 ± 0.32, p<0.001), docosahexaenoic acid (DHA) (1.51 ± 0.36 vs. 1.33 ± 0.38, p=0.03), long chain (LC) (2.44 ± 0.50 vs. 2.11 ± 0.56, p=0.005) and total (3.12 ± 0.49 vs. 2.76 ± 0.58, p=0.007)) n-3 levels. Though RBC EPA levels were not significantly different, HP had higher DHA levels (4.65 ± 0.92 vs. 3.16 ± 1.15, p<0.0001), LC (7.32 ± 1.05 vs. 5.07 ± 1.73, p<0.0001) and total n-3 (7.61 ± 1.21 vs. 5.20 ± 1.75, p<0.001). Plasma findings suggest that short-term fish consumption was greater in CS. The fact that RBC DHA levels and LC n-3 PUFA were higher in HP (while EPA levels were not different) raises the possibility that the uremic milieu upregulates the Sprecher pathway or reduces DHA retroconversion to EPA. The relatively modest amount of fish oil-associated n-3 PUFA (i.e. EPA + DHA) in HP suggest they may benefit from fish oil supplementation. This research was supported by the National Kidney Foundation of Indiana, Inc.