Myocardial infarction, often known as heart attack, kills around 4 million people in Europe and Northern Asia each year, accounting for almost one-third of all fatalities.

Experts at the University of Maryland School of Medicine discovered a link between blood type and the risk of having a heart attack at an earlier age.

The meta-analysis included data from 48 genetic studies of ischemic stroke in people under the age of 60.

These trials included 17,000 stroke patients and over 600,000 healthy participants in total. 

Researchers discovered a relationship between early stroke and a chromosomal region containing the gene that determined blood type (A, B, AB or O).

"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 D. Mitchell, Professor of Medicine UMSOM.
 
After accounting for gender and other factors, the researchers discovered that those with blood group A had an 18% higher risk of having an early stroke than those with other blood groups, while those with blood group O had a 12% lower risk.

However, the researchers emphasized that the increased risk was extremely modest, so persons in the A group should not be concerned about an early stroke possibility or undergo further screening.

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