Determinants of plasma homocysteine in relation to hematological and biochemical variables in patients with acute myocardial infarction

Background: Elevated plasma total homocysteine (tHcy) is a risk factor for coronary artery disease (CAD), but the mechanism is not known. This study evaluates the determinants and associations of tHcy in patients presenting with acute myocardial infarction (AMI). Methods: Plasma concentration of tHcy, protein C, protein S, and antitbrombin were measured in 210 (177 males and 33 females) patients with first AMI and 167 (87 males and 80 females) controls. Serum vitamin 13,21 folate, creatinine, lipid profile, fasting glucose, full blood count and red cell folate were determined. Creatinine clearance was calculated using the modification of diet in renal disease formula. Univariate and multivariate analyses were used to determine the associations of tHcy. Results: Mean tHcy was higher in male than female patients. On logistic regression analysis, the most important determinants of tHcy in the patients were age, creatinine, creatinine clearance, vitamin B 12 and red cell folate. When study patients were compared with the controls, tHcy, fasting glucose and serum creatinine were significantly higher, while creatinine clearance and HDL cholesterol were significantly lower in the study patients. Logistic regression analysis showed significant association of tHcy with AMI, odds ratio = 1.39, in the presence of other confounding factors. Conclusions: Our results show that tHcy is a significant risk factor for CAD in our patient population. The determinants in the patients are age, glomerular filtration rate and the status of vitamins B-12 and folate. The above determinants should be kept in mind when using tHcy as a risk factor for CAD.