Association between homocysteine, vitamin B12, folate, MTHFR polymorphisms and ischaemic heart disease

Abstract

OBJECTIVES: The present study investigated the association between homocysteine and ischaemic heart disease (IHD) and the factors influencing homocysteine levels. METHODS: A case control study involving 221 patients with IHD and 221 age and sex matched controls admitted to Colombo South Teaching Hospital and an analytical study involving 79 patients awaiting coronary artery bypass grafting at Nawaloka Hospitals PLC were done. RESULTS: Hyperhomocysteinaemia was a significant predictor of IHD after controlling for hypertension and hypercholesteroleamia (adjusted odds ratio 2.38). Hyperhomocysteinaemia was a significant predictor of IHD in the young but not in the elderly. Among persons below 50 years, persons with hyperhomocysteinaemia were 4.5 times more likely to develop IHD as compared to those with normohomocysteinaemia. Vitamin B^ and folate levels showed a negative correlation with serum homocysteine concentrations. The homocysteine concentration did not differ significantly with the genotypes of Methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms. CONCLUSIONS: People with hyperhomocysteinaemia have a 2-3 fold increase in risk of developing IHD. Hyperhomocysteinaemia is a predictor of IHD in the young but not in the elderly. A decrease in either vitamin B12 or folate concentrations in serum is associated with higher homocysteine concentrations whereas MTHFR A1298C and C677T gene mutations do not have an effect on the homocysteine concentrations.