Some types of blood appears to be associated with an increased risk of stroke than other researchers said the results of his study at the Scientific Sessions of the American Heart Association 2011 in Orlando, Florida.
Drawing from two large observational studies involving more than 90,000 men and women followed for over 20 years, the researchers found that:
- Blood type B was linked to a 17% increased risk of stroke in women, but not in men.
- Blood type AB was linked to a 29% increased risk of ischemic stroke among men and women.
An ischemic stroke is caused by blockage of a blood vessel in the brain. Other types of stroke are ischemic stroke, when a weakened blood vessel bursts, and transient ischemic attack (TIA or "mini-stroke"), caused by a clot temporarily.
When the researchers compared blood type O to type AB found that was linked to a 28% higher risk of stroke in women and 32% higher risk of stroke in men.
The differences in blood types reflect differences in the glycoproteins on the surface of red blood cells, which in turn affects how the immune system develops. Manson suggested this source of variation can affect the viscosity of red blood cells, so some types of groups and clots form more easily than others, reports the Associated Press.
