Blood type is linked to risk of heart disease

Blood group helps determine a person’s risk of heart disease, a study has found. People from groups A, B and AB are more at risk than those with the more common blood type O, research shows.

Individuals with the rarest blood group, AB, were far and away the most vulnerable.

Compared with people having blood type O, their chances of suffering heart disease were raised by 23 per cent. Type B blood in­creased the risk by 11 per cent, and type A by five per cent.

“While people cannot change their blood type, our findings may help physicians better understand who is at risk for developing heart disease,” said lead researcher Lu Qi, from the Harvard School of Public Health in Boston, US.

“It’s good to know your blood type the same way you should know your cholesterol or blood pressure. If you know you’re at higher risk, you can reduce the risk by adopting a healthier lifestyle, such as eating right, exercising and not smoking.”

The findings, published in the American Heart Association journal, Arteriosclerosis, Thrombosis and Vascular Biology, are based on an analysis of two large US health and lifestyle studies.

One, the Nurses’ Health Study, recruited more than 62,000 female health workers. The other, the Health Professionals’ Follow-Up Study, involved around 27,400 male health professionals.

Participants were aged between 30 and 75, and both groups were monitored for 20 years or more.

The epidemiological study compared blood groups and heart disease incidence but did not probe into the complex biological mechanisms behind the results.

However there is evidence that type A blood is associated with higher levels of the “bad” type of cholesterol, low density lipoprotein (LDL).

AB blood is linked to inflammation, which also plays an important role in artery damage.

Doireann Maddock, senior cardiac nurse at the British Heart Foundation, said: “While these findings are certainly interesting we’ll need more research to draw any firm conclusions about blood type and its role in heart disease risk”.