Aspirin Plus Celebrex May Reduce Heart Benefits
If you take a low-dose aspirin daily to reduce the risk of heart attack and stroke plus you take Celebrex for management of arthritis or other pain, the Celebrex may be preventing the aspirin from providing heart benefits. That is the word from a new study conducted by researchers at the University of Michigan.
Millions of Americans who have a history of a heart condition, including angina and heart attack, take a low-dose (81 mg) aspirin tablet every day as a preventive measure, because it reduces the risk of blood clot formation. Millions of people who have arthritis or other types of pain also take Celebrex (celecoxib), a type of drug known as a coxib or COX-2 inhibitor. Because Celebrex has the potential to promote blood clot formation, physicians often put their arthritis patients on low-dose aspirin to help prevent this complication. According to a 2004 study in the Archives of Internal Medicine, more than 50 percent of older patients taking COX-2 inhibitors long-term were also taking aspirin.
Now a new study suggests that this attempt to safeguard heart patients and arthritis patients with a combination of low-dose aspirin and Celebrex may not be a good idea. The University of Michigan researchers found that celecoxib and other coxibs interfere with the ability of aspirin to prevent the formation of blood clots. Currently Celebrex is the only coxib on the market.
William L. Smith, PhD, the study’s senior author and chair of the biochemistry department at the University of Michigan Medical School, noted in the University’s news release that “The greatest risk is having people take Celebrex who are taking aspirin for cardiovascular problems that are known to be mitigated by aspirin, including patients with unstable angina or those at risk for a second heart attack.”
The research for this study was conducted in animals. The investigators found that animals who received both Celebrex and low-dose aspirin had more clumping of platelets, which is the first stage of blood clotting, than animals who were given low-dose aspirin alone.
It is possible that taking a larger dose of aspirin (a “regular” tablet of 324 mg) or taking low-dose aspirin and Celebrex at different times of the day may allow aspirin to be more effective. For now, however, the effects seen in this study need to be replicated in humans. Dr. Smith noted that if the same results are observed in people, scientists will then need to determine if a regimen can be worked out that allows people to take both aspirin and Celebrex so patients can experience both heart benefits and pain relief.
Rimon G et al. Proceedings of the National Academy of Sciences, advance publication online Dec 1
University of Michigan news release, Dec. 14, 2009