People having a non-O blood group -- A, B, AB -- may be at 9 per cent higher risk of suffering a heart attack and overall cardiovascular mortality compared to those with O-blood group, a research has shown.

The findings revealed that the higher risk may be due to have greater concentrations of von Willebrand factor -- a blood clotting protein -- which has been associated with thrombotic events.  People with A blood group are known to have higher cholesterol, which is a leading risk factor for heart attack. 

Further, those with non-O blood group also have higher galectin-3, a protein linked to inflammation and worse outcomes in heart failure patients, the researchers said. "The study demonstrates that having a non-O blood group is associated with a 9 per cent increased risk of coronary events and a 9 per cent increased the risk of cardiovascular events, especially myocardial infarction," said lead author Tessa Kole, a student at the University Medical Centre Groningen in the Netherlands. 

The study was presented at the Heart Failure 2017 and the 4th World Congress on Acute Heart Failure. For the study, the team conducted a meta-analysis on O and non-O blood groups and incident cardiovascular events including myocardial infarction (heart attack), coronary artery disease, ischaemic heart disease, heart failure, cardiovascular events and cardiovascular mortality. "Blood group should be considered in risk assessment for cardiovascular prevention, together with cholesterol, age, sex and systolic blood pressure," Kole suggested.