The content of docosahexaenoic acid in serum phospholipid is inversely correlated with plasma homocysteine levels in patients with end-stage renal disease

Patients with end-stage renal disease (ESRD) have a high morbidity and mortality from cardiovascular disease. An elevated homocysteine level is an independent predictor of cardiovascular events in patients with ESRD. Interestingly, some studies have found an inverse relationship between the content of marine n-3 polyunsaturated fatty acids (PUFAs) and homocysteine levels, but data are ambiguous. In patients with ESRD, we hypothesized that serum phospholipid n-3 PUFA content would inversely correlate with homocysteine levels in plasma and that supplementation with n-3 PUFA would reduce plasma homocysteine levels. In a double-blind, randomized, controlled design, 206 patients with documented cardiovascular disease and treated with hemodialysis for a minimum of 6 months were randomized to treatment with daily supplement of 1.7 g n-3 PUFA or placebo (olive oil) for 3 months. The content of n-3 PUFA in serum phospholipids and homocysteine levels in plasma were measured at baseline and after 3 months of intervention. A dietary questionnaire was filled out at baseline, and study participants were divided into groups of low, intermediate, and high fish intake. Docosahexaenoic acid was inversely correlated with homocysteine at baseline (coefficient = −0.161; P = .03). Homocysteine was not related to self-reported fish intake. Supplementation with n-3 PUFA did not reduce homocysteine levels compared with placebo (mean ± SD difference, −0.3 ± 7.8 versus 0.3 ± 7.1; P = .58). The content of docosahexaenoic acid in serum phospholipids is inversely correlated with plasma homocysteine levels, and supplementation with n-3 PUFA does not reduce homocysteine levels in patients with ESRD.