Homocysteine, folate and vitamin b12 in patients with coronary heart disease.

BACKGROUND/AIMS: Homocysteine and possibly also folate and vitamin B(12) are involved in the pathogenesis of cardiovascular disease. We investigated the prevalence of hyperhomocysteinemia in patients with coronary heart disease (CHD), as well as folate and vitamin B(12), the main nutritional factors determining the level of homocysteine.

METHODS: Patients with angiographically documented CHD were prospectively investigated (n = 315, 70% male, mean age 61 [range 36-81] years). Fasting total serum homocysteine was determined by high-performance liquid chromatography and fluorescence detection. Folic acid and vitamin B12 were measured with AxSYMR Systems.

RESULTS: Median homocysteine concentrations for homocysteine, folate and vitamin B12 were 12.8 micromol/l, 6.8 ng/ml and 345 pg/ml, respectively. Homocysteine levels >10 micromol/l were found in 82% of men and 73% of women. In 19% of the patients serum folate was <3 ng/ml and 22% of the patients had serum vitamin B12 values <250 pg/ml. In a multivariate linear regression model, folate and vitamin B(12) showed significant negative correlations to homocysteine, explaining 5 and 3% of its variability. Age and creatinine were the most important determinants for serum homocysteine, contributing 12 and 7%, respectively.

DISCUSSION: The main determinants of total homocysteine in patients with CHD are higher age and increased creatinine. The association of lower levels of folate and vitamin B12 with higher levels of homocysteine may indicate poor dietary habits in these patients.