The blood type describes the variety of chemicals in the red blood cells. The most familiar blood types are A, B, AB, and O. However, there could be subtle variations due to mutation in genes that may make a person susceptible to certain diseases.

A new meta-analysis from researchers at the University of Maryland's School of Medicine reports that the blood may be linked to the risk of the early onset of stroke in younger adults under the age of 60.

Which Blood Type Increases Risk of Early Onset of Stroke?

In the study, titled "Contribution of Common Genetic Variants to Risk of Early Onset Ischemic Stroke" published in the journal Neurology, researchers analyzed 46 genome-wide studies with data from 16,730 cases of stroke and 599,237 non-stroke control participants.

They looked at blood type and its link to the risk of early onset ischemic stroke (EOS), which happens in people before they reach the age of 60. They found that the greatest association for stroke risk is in blood types A and O.

According to Medical News Today, people with blood type A were at the highest risk for EOS at 16%, while those with blood type O have a 12% lower chance. More so, people who had a stroke tend to have blood type B compared to control

Study author Dr. Braxton D. Mitchell, a professor at UM's Departments of Medicine and Epidemiology and Public Health, said to the news outlet that the risk for stroke could be related to an increased risk for blood clots that form among people with blood type A.

 Blood Type and Stroke Risk: Meta-Analysis Found Link Between the Two Factors in People Under 60 Years Old
(Photo : Pixabay/Belova59)
Blood Type and Stroke Risk: Meta-Analysis Found Link Between the Two Factors in People Under 60 Years Old

ALSO READ: Physical Medicine and Rehabilitation: New Study Suggests Stroke Patients May Take Up to 3 Months to Recover

Should People Be Worried?

Although the findings may sound alarming, researchers noted that the additional risk of stroke in people with blood type A is small. The findings also do not suggest any need for extra vigilance or additional screening for people in this group.

Senior author Steven Kittner, a vascular neurologist from UM, said in the news release that they have yet to understand why having a blood type A increases the risk of stroke, but it is likely to have something to do with blood-clotting factors in which platelets and cells in blood vessels play a role in the development of blood clots.

Limitations of the Study

The study gives new insight into the risk of early onset stroke, however, it is not without limitations. According to Science Daily, one of its limitations is its relative lack of diversity among participants as it mainly includes people of European descent. That means a follow-up with a more diverse group is needed.

Secondly, the study does not show a causal relationship between blood types and stroke and so further data is needed to see how the former could influence the latter.

Lastly, the sample size is limited that is limiting the ability of researchers to look at unique subtypes. However, even with the said limitations, the study is a warning that many adults under the age of 60 experience a stroke, and knowledge of it could lead to addressing possible risk factors.

RELATED ARTICLE: Risk of Stroke Can Be Reduced by 16 Percent If You Live Near Green Spaces, Study Reveals

Check out more news and information on Stroke in Science Times.