Aspirin Study Reveals a Sharp Gender Divide

Men and women react differently to a host of compounds, and now it appears that there is a sharp gender divide when it comes to aspirin, a team of researchers led by a Long Island heart specialist will report today.

The results of the research, published in the Journal of the American Medical Assn., is what is known as a meta-analysis, which means scientists gathered pertinent medical data on aspirin and its protective effects and reanalyzed it.

Going into the research, the team, led by Dr. David Brown, chief of cardiology at Stony Brook University Hospital, was well aware of aspirin therapy’s benefits for people who had experienced a heart attack or stroke. What had remained less clear was whether there were benefits for those who had never had either.

In short, could an aspirin tablet protect people from ever having a heart attack or stroke?

After analyzing the effects of aspirin therapy in more than 95,000 patients who had participated in controlled clinical studies from 1966 to 2005, Brown and his colleagues found that although aspirin reduced cardiovascular risks, it did so across a sharp gender divide.

The old pain-relief standby acts as a preventive of heart attacks in men and staves off strokes in women.

“Aspirin affects platelets differently in men and women,” Brown said of the sticky, colorless, disk-shaped cells in the bloodstream that are involved in the clotting of blood. Aspirin prevents platelets from clumping together. Women are more likely than men to thwart aspirin’s anti-clumping activity. Therefore, aspirin’s gender difference with respect to platelets might be one reason that men and women have varying reactions to the medication, but it is not the entire reason, he said.

Other theories might involve differences in various hormones on the cardiovascular system, Brown added, but a far more detailed explanation has yet to be found.

Brown and colleagues say the findings, nevertheless, have led the team to recommend that patients and physicians weigh aspirin’s pros and cons.

In the research, the cases of 51,342 women and 44,114 men were analyzed, and demonstrated that without aspirin therapy, women were more likely to have strokes and men were more likely to have heart attacks.

The study concluded that aspirin conferred a 12% reduction in risk of stroke for women, and a 14% reduction in heart attack for men.