Does Your Blood Type Indicate Stroke Risk?

Type B and AB blood types at a higher risk of stroke

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Some individuals may be at a higher risk of stroke simply by nature of their blood type. Those with blood type AB may be at an increased risk of stroke regardless of other factors.

Type AB blood is the most uncommon type, with less than 4 percent of American Red Cross donations consisting either AB positive or AB negative.

"Exercise and eat healthy to lower stroke risk."

Lu Qi, lead researcher and an assistant professor in the department of nutrition at the Harvard School of Public Health, said that the finding could be used to pinpoint individuals who may be at a moderately higher stroke risk.

Though the risk could not be changed, it would allow individuals with the highest risk blood types to check their other risk factors, and it could be recommended that they follow a more intensive, healthy lifestyle such as consuming healthy foods, exercising regularly and avoiding tobacco.

During the study researchers reviewed data from the Nurses’ Health Study, which included 61,973 women, and the Health Professionals Follow-up Study, which included 27,808 men. The studies followed patients for at least 20 years. Patients self-reported their blood type. Scientists confirmed the accuracy of those reports through blood testing, finding that patients reported with 93 percent accuracy in the former study, and 90 percent accuracy in the latter research.

All blood types were examined including types A, B, AB and O. During follow up, 2,550 patients had a stroke.

Investigators found that having type AB blood increased the risk of ischemic stroke by 29 percent in both men and women. As compared against type O blood, type AB blood was linked to a 28 percent increased risk of stroke in women and a 32 percent added risk of stroke in men.

Women with type B blood also were found to be at a 17 percent increased risk of stroke, but men with this blood type were not found to be at an added risk. The findings were not affected by age, smoking or drinking status or physical activity.

The study was recently presented at the American Heart Association's annual meeting in Orlando, Fla.

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Review Date: 
November 16, 2011
Last Updated:
November 17, 2011