Wednesday, April 13, 2005

Wonder Goes Under

The Wonder Drug of the 20th Century will probably not finish out the 21st Century with its "wonder-ful" reputation intact. You may have heard about a recent New England Journal of Medicine study concluding that aspirin "therapy" may prompt serious digestive problems but very little cardiovascular protection for middle-aged women. This study is worth a closer look - especially for those who have been sold on the idea of aspirin as the silver bullet of heart health - because as other studies have revealed, there are a number of potential pitfalls for those who sign on for the Wonder Drug treatment. The scope of his newest aspirin study is impressive. Researchers at the Brigham and Women's Hospital recruited well over 39,000 healthy women over the age of 45 who had experienced no cardiovascular events (such as heart attack or stroke). For a period of 10 years, half the group took 100 mg of aspirin every other day and half the group took a placebo. Now, if we're to believe the ads we see on television, the result of this study is a no-brainer, right? Aspirin surely proved to be protective. Right? Well...not exactly. Several hundred major cardiovascular events were reported in both groups - not surprising in a cohort of nearly 40,000 over a decade. But the placebo group reported only 45 more cardio events than the aspirin group - a statistically insignificant difference. Aspirin provided virtually no protection from heart attack, although those in the aspirin group had a 24 percent reduced risk of ischemic stroke. In a study of this size, those are significant results. But here's the troubling part: Women in the aspirin group were found to have a 40 percent increased risk of gastrointestinal bleeding. But this was not just any bleeding: it was bleeding severe enough to require transfusions. This sharply increased risk of internal bleeding sort of takes the edge off the good news: Women over the age of 65 who took aspirin were found to have a 30 percent reduced risk of ischemic stroke and a 34 percent reduced risk of heart attack. The Brigham and Women's research is by no means the first to find aspirin on wobbly footing. This past July the American Heart Journal published a UK study in which nearly 280 subjects who had suffered a first heart attack were given 300 mg aspirin daily, warfarin (a blood thinner) or a placebo. After two years, researchers reported that neither the aspirin nor the warfarin therapies provided any greater protection against death, nonfatal stroke, or nonfatal heart attacks than the placebo. Subjects that received aspirin therapy, however, were nearly twice as likely to suffer a heart attack or stroke as were those who took warfarin or placebo. Gastrointestinal problems were also elevated in the aspirin group. In an interview with Reuters Health, the lead researcher of the study, Dr. John G.F. Cleland, stated that any theoretical benefit of using aspirin after a heart attack "is outweighed by real evidence of harm." But the problems linked with aspirin don't stop there. In a previous alert I told you about a French study that showed how severe angina and fatal heart attacks might be prompted by the sudden halt of regular aspirin intake. In reviewing more than 1,200 cases of coronary episodes, researchers found 51 patients who suffered heart attacks or other severe coronary problems less than one week after they stopped using aspirin. Subjects with a history of heart disease were at particularly high risk. One of the troubling concerns of this outcome is the fact that patients preparing for surgery are regularly advised to discontinue aspirin therapy to avoid excess bleeding during their operations. The French team told Reuters news service that doctors should not advise their coronary patients to stop using aspirin, and even stated that aspirin therapy "cannot be safely stopped in any case." Aspirin is generally regarded as so benign that most people would find it hard to imagine that you could actually experience withdrawal symptoms by quitting an aspirin regimen. The lead author of the Brigham and Women's research, Paul M. Ridker, M.D., told Reuters Health that the study clearly illustrates, "the importance of studying women as well as men in major cardiovascular clinical trials." I'm trying to suppress the urge to say something like, "Well DUH!" And I shouldn't take Dr. Ridker to task; after all, he's the one who headed up this revealing study. But it's been clear for many years now that cardiovascular fitness is not exclusively a male health issue. Studies that specifically examine cardiovascular issues among women are long overdue.


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