The high concentration of plasma total homocysteine is recently considered an independent risk factor for atherosclerosis. The purpose of this study was to provide reference ranges for plasma homocysteine levels and to investigate the relationship between plasma homocysteine and cardiovascular risk factors in healthy Korean men.

Anthropometric parameters, alcohol intake, cigarette use and nutrient intake were determined in 166 healthy men within a wide age range(30-69 yr). Serum levels of lipids, glucose and insulin levels during oral glucose tolerance test(OGTT), plasma amino acid concentrations and levels of antioxidant nutrients and enzymes were also measured. Hyperhomocysteinemia was defined as plasma homocysteine levels above the 90th percentile(≥15micromol/L) of respective plasma homocysteine distribution in study subjects. Characteristics of hyperhomocysteinemic men(n=16) were compared to normohomocys- teinemic men(n=16) matched for age and body mass index.

Plasma total homocysteine values ranged from 2.4 to 38.1micromol/L, a skewed, right-tailed distribution. The homocysteine levels of 25th, 50th and 75th percentile were 7.02, 9.61 and 12.4micromol/L, respectively. The mean concentration of plasma total homocysteine was 10.7micromol/L. Plasma total homocysteine level was positively correlated to body mass index, serum cholesterol and triglyceride levels and alcohol intake, but negatively correlated to serum bata-carotene concentration. In multivariate analysis, serum triglyceride level was the strongest determinant of plasma total homocysteine concentration. There were no significant differences between two groups in waist to hip ratio, alcohol intake, cigarette use, blood pressure and serum levels of glucose and insulin during OGTT. Hyperhomocysteinemic men had significantly higher mean values of serum triglyceride(258mg/dl), total cholesterol(226mg/dl), and LDL-cholesterol(140mg/dl) than normohomocysteinemic men. Hyperhomocysteinemic men showed a decrease in lipid corrected values of serum bata-carotene and alpha-tocopherol and plasma concentrations of serine and taurine, when compared to normohomocysteinemic men. The mean intakes of vitamin B6, folate, vitamin B12 and bata-carotene tended to decline by 25-30% in hyper- homocysteinemic group, when compared to normohomocysteinemic group.

Our results indicate that healthy Korean men with hyperhomocys- teinemia show signs of hyperlipidemia and decreased antioxidants nutrients and these factors increase risk for coronary artery disease. In addition, hyperhomocysteinemia may affect amino acid metabolism related to homocysteine.