Plasma homocysteine thiolactone adducts associated with risk of coronary heart disease

Background: Homocysteine thiolactone adducts have been proposed as the culprit of homocysteine related cardiovascular diseases. We studied the association of these adducts in plasma, and the gene polymorphism of paraoxonase-2 with coronary heart disease. Methods: 254 patients and 308 controls were recruited for the study. Homocysteine thiolactone adducts were determined with ELISA. The codon 311 polymorphism of paraoxonase-2 gene was genotyped by using polymerase chain reaction and restrictive digestion. Results: The plasma level of homocysteine thiolactone adducts were significantly higher in patients than in controls (40.65 +/- 10.87 u/ml vs. 30.58 +/- 10.20 u/ml, P < 0.01), with odds ratio of 7.34 (95% confidence interval 4.020 similar to 13.406, P < 0.01), and increased according to the number of atherosclerotic coronary arteries: 35.59 +/- 10.34 units/ml (n = 76); 41.88 +/- 8.83 (n = 70) and 43.13 +/- 11.47 (n = 108) in subjects with 1, 2 and 3 affected arteries, respectively (r = 0.174, P < 0.01). The frequency of CC genotype was significantly higher in patients with coronary heart disease (7.48%) than in controls (1.62%, P < 0.01), with adjusted odds ratio of 4.367 (95% confidence interval: 1.178 to 16.191, P < 0.01), so was the C allele (23.2% vs. 14.9%, P < 0.05). Conclusions: High plasma homocysteine thiolactone adducts and the CC 311 genotype of paraoxonase-2 gene may be the emerging risk factor for coronary heart disease. (C) 2005 Elsevier B.V. All rights reserved.