Ankle-brachial index, and resulting aspirin therapy, may not be needed for healthier patients
MONDAY, March 1 (HealthDay News) -- A new Scottish study raises questions about the value of both the ankle-brachial index, a test widely used to diagnose the risk of blood vessel problems in the legs, and the common practice of prescribing low-dose aspirin to reduce that risk.
The ankle-brachial index (ABI) measures blood pressure in the arm and the ankle. Conventional wisdom is that a low ABI number is a sign of peripheral artery disease, a narrowing or blocking of arteries in the legs that can lead to clotting problems in the lower limbs, heart disease or stroke. Aspirin reduces the chances of such blood clots but can raise the risk of bleeding episodes.
The Scottish study, which followed nearly 29,000 cardiovascular-healthy men and women aged 50 to 75 for nearly 10 years and assigned 3,350 to a test of aspirin therapy on the basis of ABI test results, found no decreased incidence of blood vessel problems -- but a higher incidence of major bleeding incidents -- in the aspirin group.
To Dr. F. Gerald R. Fowkes, a professor of epidemiology at the University of Edinburgh and lead author of the report in the March 3 issue of the Journal of the American Medical Association, the results show that routine use of the ABI test for screening in people without risk factors for cardiovascular disease might not be warranted.
"That there was no difference in the two groups is partly due to the fact that when you screen people who in general feel quite healthy, some of those individuals don't continue taking aspirin because they feel quite well," Fowkes said.
So ABI test screening might be reserved for people with known risk factors, he said. As a general screening tool, "our trial would suggest that in clinical practice one would have to approach this with caution," Fowkes said. "If we are going to use the
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