Washington, Sept. 21 (Reuters): A relatively new blood test for people with diabetes can predict their risk of developing heart disease, US researchers reported yesterday.

Two separate studies suggest that people with both type 1 and type 2 diabetes should regularly take the haemoglobin A1c test, on top of their regular checks of blood sugar.

The HA1c test looks for glycated haemoglobin, also called glycosylated haemoglobin, and is a measure of how well blood sugar is controlled.

In one study, Dr. Sherita Golden and colleagues at Johns Hopkins University in Baltimore re-analysed the data from 13 studies involving nearly 10,000 people from North America and Europe and found those with higher levels had much higher risks of heart and artery disease.

Writing in the Annals of Internal Medicine, they said a 1 percentage point increase in HA1c predicted an 18 per cent increase in risk for total cardiovascular disease and a 28 per cent risk for peripheral vascular disease ? clogged arteries in the legs, for instance.

Although diabetes is known to double the risk of heart disease death, Golden said the specific relationship was unclear.

?As a result, many people living with diabetes monitor their health for well-known risk factors for heart disease, such as obesity, cholesterol levels and blood pressure ? but, the big unknown has been the role of blood sugar levels in managing their risk of developing cardiovascular disease,? she said in a statement.

A second study found similar results. Dr. Kay-Tee Khaw of Cambridge University and colleagues at Britain?s Medical Research Council studied 10,030 people aged 45 to 79 for six years. They found a 21 per cent increase in cardiovascular ?events? such as heart attack, for every 1 percentage point increase in haemoglobin A1c above 5 per cent.

?Persons with HA1c concentrations less than 5 per cent had the lowest rates of cardiovascular disease and mortality,? they wrote.