New research highlights that a person with blood type A might be more likely to have an early-onset stroke while a person with blood type O is less likely to suffer one.
The study, published on Wednesday in the journal Neurology, analyzed 48 studies involving almost 17,000 people with a stroke and more than 570,000 people with no past reported strokes.
“Our meta-analysis looked at people’s genetic profiles and found associations between blood type and risk of early-onset stroke. The association of blood type with later-onset stroke was much weaker than what we found with early stroke,” said study co-principal investigator Braxton Mitchell.
Which blood types are more likely to suffer strokes?
Mitchell and his research team, from University of Maryland School of Medicine, examined the potential correlation between blood type and ischemic stroke risk, the most common type of stroke. Looking at the four main blood groups, study included the blood types A, AB, B, and O, they found that people with blood type A had the highest risk for early-onset stroke, which occurs before age 60.
To get to this conclusion, the researchers divided participants by blood type and compared this with stroke status: early stroke, late stroke, and no stroke. They found that people with early stroke were more likely to have blood type A and less likely to have type O when compared to people who had a stroke at a later age or people who had no stroke history.
“Our meta-analysis looked at people’s genetic profiles and found associations between blood type and risk of early-onset stroke."
Braxton Mitchell
Furthermore, the team noted that people with both early and late stroke were more likely to have type B when compared to a control group.
In 2020, nearly 3.5 million people worldwide died from an ischemic stroke, according to the American Heart Association.
University of Maryland School of Medicine Dean Mark Gladwin noted the urgency of continuing the research. “This study raises an important question that requires deeper investigation into how our genetically predetermined blood type may play a role in early stroke risk,” he said.