Blood types are categorised into four groups, namely A, B, AB and O. These four blood groups are different from each other, based on the number of antigens present or absent in the blood. The “+” and “-” sub-categorisations are done on the basis of the presence or absence of an antigen, known as the “Rh factor”. For example, if the Rh factor is present in a person with blood group A, then their blood type is A positive.
According to a recent study, people with blood groups A, B and AB are at a higher risk of a heart attack. The study published in Arteriosclerosis, Thrombosis and Vascular Biology, an American Heart Association (AHA), revealed that people with blood groups A or B have a combined 8 per cent higher risk of heart attack than those with O blood group. The result was derived from an analysis that involved 4 lakh people.
Another study done by the European Society of Cardiology, in 2017, involved a similar analysis of more than 13.6 lakh people. The result, of the study, revealed that people with non-O blood groups were at a 9 per cent higher risk of coronary and cardiovascular incidents in comparison to someone with an O blood group.
As per the study, people with blood group B were at a 15 per cent higher risk of heart attack as compared to the O- type group. The highest risk was however determined to be for those with blood group A. People with this blood group are at an 11 per cent higher risk of heart attack and failure in comparison to the O- type.
The reason given for the increased risk in all blood groups except O- was given to be their increased susceptibility to blood clots. Blood clotting protein, von Willebrand factor (VWF), was found to be more in non-O blood groups. The protein is linked to thrombotic effects. It was found that people with blood groups A and B were at 44 per cent higher risk of blood clots as compared to the O- type.
