Blood Group May Affect Heart Attack Risk

Researchers have found that people with A, B, and AB blood types may be at greater risk of cardiovascular events - particularly heart attack - than individuals with O blood types.

Lead study author Tessa Kole, of the University Medical Center Groningen in the Netherlands, and colleagues say that their findings suggest that healthcare professionals should consider a person’s blood group when assessing their cardiovascular risk.

The researchers recently presented their results at Heart Failure 2017, the annual meeting of the European Society of Cardiology, held in Paris, France, medicalnewstoday.com reported.

Kole and team came to their findings by conducting a meta-analysis of studies that reported participants’ blood types and the incidence of cardiovascular events, including heart attack, heart disease, heart failure, and cardiovascular death.

The data included more than 1.3 million adults who were a part of 11 cohorts across nine studies.

Researchers used the data to assess how each blood group might impact the risk of coronary events, combined cardiovascular events, and fatal coronary events. The team identified 771,113 individuals with a non-O blood group and 519,743 individuals with an O blood group in the analysis of all coronary events. Among people with a non-O blood group, 1.5% (11,437) experienced a coronary event, compared with 1.4% (7,220) of people with an O blood group.

In the analysis of combined cardiovascular events, researchers identified 708,276 people with a non-O blood group and 476,868 people with an O blood group. Among individuals with a non-O blood group, 2.5% (17,449) experienced a cardiovascular event, compared with 2.3% (10,916) who had an O blood group.

Explaining what these findings show, Kole says, “We demonstrate that having a non-O blood group is associated with a 9% increased risk of coronary events and a 9% increased risk of cardiovascular events, especially myocardial infarction.”

While the study was not designed to pinpoint the mechanisms underlying the link between blood type and cardiovascular risk, the researchers propose some explanations.

For example, they note that individuals with non-O blood types have higher concentrations of a blood-clotting protein called von Willebrand factor, which previous studies have linked to thrombotic events.

Additionally, they point out that people with non-O blood groups - especially those with an A blood type - tend to have higher cholesterol levels, which is a known risk factor for poor cardiovascular health.