“The number of early stroke patients is increasing. These younger people have a very increased risk of disability and death and yet there is little research on the causes of these early strokes, ”recalls the lead author, Dr. Steven J. Kittner, professor of neurology and neurologist clinician at the University of Maryland Medical Center.
The analysis shows, in other words, that a person’s blood type may be linked to their risk of having an early stroke, according to this new meta-analysis of all available data from genetic studies focused on on ischemic strokes, caused by a blockage of blood flow to the brain, occurring in young adults under the age of 60.
Early stroke patients are more likely to have blood group A
This meta-analysis of 48 studies on genetics and ischemic stroke, involving a total of 17,000 stroke patients vs nearly 600,000 healthy, stroke-naïve controls identifies
- a link between an early stroke – occurring before the age of 60 – and the area of the chromosome that includes the gene that determines whether the blood type is A, AB, B or O;
- early stroke patients are more likely to have blood group A and less likely to have blood group O (the most common blood group) bs people with late stroke and people who have never had a stroke;
- having an early or/and late stroke is also associated with a higher probability of having blood group B vs controls;
- after adjusting for possible confounders, people with blood group A have a 16% increased risk of early stroke vs other blood groups;
- people with blood group O have a 12% reduced risk of early stroke vs other blood groups.
“This meta-analysis therefore identifies associations between blood type and the risk of early stroke. The association of blood type with late-onset stroke, on the other hand, is much weaker.conclude the researchers who nevertheless point out that the variation in risk associated with blood group remains modest.
Thus, when one has a blood group, group A, it is not “useful” to worry should not worry about having an early stroke or even engaging in additional screening. However, the analysis raises the question of the reasons for this association, a question whose answer could perhaps help to find new ways to prevent these devastating events in young adults.