Research - Hoorn

High homocysteine is associated with heart attacks in type 2 diabetes patients

Background
Type 2 diabetes causes excess illness and death, which is largely due to coronary events. The increased cardiovascular risk is not fully explained by conventional cardiovascular risk factors. Alternative risk factors, such as homocysteine, may partly explain this increased risk.

In previous studies, homocysteine was found to be a strong risk factor for all-cause and cardiovascular mortality in type 2 diabetics. However, there is no data on the association of homocysteine with coronary events in type 2 diabetes patients.

Why did the researchers do this study?
To determine the effect of homocysteine on the risk of fatal and nonfatal coronary events in type 2 diabetes patients.

Who was studied?
501 Caucasian men and women, aged 50-75 years, who were part of the Hoorn study - a population-based cohort study.

How was the study done?
After an overnight fast, serum homocysteine, glucose, HbA1c, creatinine, total cholesterol, HDL cholesterol and triglycerides were measured from each participantÕs blood sample. Participants were classified as smokers, nonsmokers or former smokers. Body Mass Index, waist-to-hip ratio, blood pressure, ankle-brachial blood pressure and resting electrocardiogram were also determined.
After 10 years, death certificates were reviewed for cause of death. Information about nonfatal coronary events was obtained by reviewing medical records of the hospital of Hoorn.

What did the researchers find?
The incidence rate for coronary events was higher in diabetics than in nondiabetics.

In diabetes patients, the risk of coronary events increased 28% for each 5 _mol/L increment of homocysteine. This risk was independent of age, sex, hypertension, total cholesterol, HDL cholesterol, cigarette smoking, body mass index and Glomerular filtration rate. What are the implications of the study? Homocysteine is significantly associated with coronary events in type 2 diabetes patients, independent of traditional cardiovascular risk factors. Investigation of the effect of treatment with vitamin B on prognosis of type 2 diabetes patients is warranted. Reference: Becker A, et al. Hyperhomocysteinemia is associated with coronary events in type 2 diabetes. Journal of Internal Medicine 2003; 253: 293-300.

HOMOCYSTEINE FACT:

Lowering homocysteine concentrations by 3 umol/l from current levels (achievable by increasing folic acid intake) would reduce the risk of ischaemic heart disease by 16%, deep vein thrombosis by 25%, and stroke by 24%.