Correlation between plasma total homocysteine and copper in patients with peripheral vascular disease

Background: Increased concentrations of both plasma total homocysteine and copper are separately associated with cardiovascular disease. Correlations between plasma total homocysteine, trace elements, and vitamins in patients with peripheral vascular disease have not been investigated. Methods: The concentrations of trace elements in plasma were determined by the multielement analytical technique of total-reflection x-ray fluorescenc e spectrometry. Plasma total homocysteine Tvas determined by HPLC. Results: In the univariate and multivariate regression analyses, copper was positively correlated with plasma total homocysteine in all subjects (coef ficient +/- SE, 0.347 +/- 0.113; P = 0.0026 and coefficient +/- SE, 0.422 /- 0.108; P = 0.0002, respectively), and in patients with peripheral vascul ar disease (coefficient a SE, 0.370 +/- 0.150; P = 0.016; and coefficient /- SE, 0.490 +/- 0.151; P = 0.0025, respectively). Correlation between copp er and plasma total homocysteine was not detected in healthy control subjec ts. The concentration of calcium in plasma (67.5 vs 80.8 mu g/g) was signif icantly lower in the patients than in the control subjects (P = 0.02). When the patients were divided into groups, the patients with suprainguinal les ions had significantly higher copper concentrations (P = 0.04) and signific antly lower selenium and calcium concentrations (P = 0.01 and 0.008, respec tively) than the healthy subjects. Patients had higher concentrations of au toantibodies against oxidized LDL and concentrations of thiobarbituric acid -reactive substance than the healthy subjects (P <0.0001 and P = 0.001, res pectively). The concentrations of plasma total homocysteine and alpha-tocop herol were significantly higher, and the concentrations of vitamin B-6 and beta-carotene were lower in the patients than the healthy subjects. Conclusion: Our findings suggest that the atherogenicity of homocysteine ma y be related to copper-dependent interactions. (C) 2000 American Association for Clinical Chemistry.