Homocysteine and cardiovascular risk in patients with diabetes mellitus.

BACKGROUND AND AIM: Diabetes mellitus is the most common metabolic disorder in the Western world with coronary artery disease as its leading cause of mortality. Conventional coronary risk factors do not explain the high morbidity rate and there is strong evidence linking hyperhomocystinemia and premature atherosclerosis. Therefore, we reviewed the relationship between homocysteine and diabetes mellitus. DATA SYNTHESIS: The literature dealing with diabetes mellitus, B vitamins and metformin was reviewed. Some studies show higher than normal fasting and postmethionine load levels of plasma homocysteine in diabetes patients, particularly in those with nephropathy and microalbuminutia. Metformin use and low plasma B vitamins are other potential mechanisms resulting in hyperhomocysteinemia in these patients.
CONCLUSIONS: Abnormal homocysteine concentration is prevalent in subsets of diabetic patients; its relationship with excess cardiovascular morbidity is not yet clear. Consequently, large prospective studies are essential in order to follow the effects of homocysteine and its normalization on accelerated artherosclerosis in diabetes.