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LOW-DOSE ASPIRIN AND VITAMIN E IN PEOPLE AT CARDIOVASCULAR RISK (September 2001) This report by Italian investigators has been touted as proving that low-dose aspirin should be considered by everyone at increased risk for heart attack or stroke. That appears to include everyone over age 65 (called by the authors, "old age"!). A total of 4,495 men and women ages 50 to over 80 participated in the study. Each had to have at least one risk factor for heart disease or stroke. These included: high blood pressure, a very elevated blood cholesterol level, obesity, age over 65 years, and diabetes. Their definition of obesity would include those Healthful Life would consider as overweight, but not frankly obese. Two-thirds had hypertension defined as systolic blood pressure over 160 millimeters of mercury or diastolic pressure over 95 millimeters of mercury. They were given aspirin 100 milligrams a day (a small dose) or vitamin E 300 milligrams a day (an amount in the range of standard vitamin E supplements). The study lasted an average of 3.6 years, at which point it was stopped for "ethical" reasons (they say they had proved their point). At that time, the results supposedly showed no benefit for vitamin E, but a reduction among aspirin users in occurrence of fatal heart attack, non-fatal heart attack, fatal stroke, non-fatal stroke, and arterial disease involving blood vessels other than those in the heart and head. The extent of reduced risk in the various categories ranged from 20 to 44 percent. Aspirin users had increased bleeding, mainly intestinal. The authors did not think this fourfold increase in bleeding complications was anything to worry about. Commentary: This study is not nearly as persuasive as the authors and an accompanying editorial suggest. Here are some of the problems: 1. The numbers of events in each group are small. For their major endpoints (death from stroke or heart attack, non-fatal heart attack or stroke), there were only 45 events, compared to 64 in those not getting aspirin. When subdivided into stroke or only heart attack, the numbers in each group were even smaller. 2. Most of the results are not statistically significant. The reduction in deaths due to heart attacks and strokes were barely statistically significant, but the primary focus, the major combined endpoint (fatal stroke plus fatal heart attack, non-fatal heart attack, non-fatal stroke) was not. The only other endpoint that was significant for any major category was peripheral artery disease reduction in those given vitamin E (which the authors conclude is of no benefit). If you do not have statistical significance, you had better be very careful in your interpretations - and public policy should not be based on studies that are not statistically significant. 3. The investigators do not really have carefully matched groups. The extent of the hypertension and the effectiveness of its treatment are not taken into consideration. The same is true for the height of the blood cholesterol level. There is no distinction between being moderately overweight and being really obese. These results could be related to differences in the groups, not the aspirin. 4. We are given no breakdown of results separately for men and women. 5. Even if the authors do not seem to be very concerned, a fourfold increase in bleeding is a worry only if it is serious bleeding.
for both aspirin and vitamin E. The authors quote other studies that support their results with aspirin, but they do not quote studies that are not supportive. Healthful Life does not support use of aspirin as a preventive in those with no increased risk for heart attack or stroke. The benefit is unclear and the dangers of bleeding are small, but real. Healthful Life is also not ready to advocate aspirin for those with risk factors for heart attack or stroke. We believe it is much better to control the major risk factors (high blood pressure, high cholesterol, smoking, in particular). And, we reject the silly notion that being over age 65 is "old age" and should be considered all by itself a risk factor for heart disease or stroke justifying aspirin treatment. The role of vitamin E in prevention of heart attacks, as pointed out in this and another recent study, is equally murky. There are both supportive and negative studies. Certainly, if you have risk factors for coronary heart disease, you should try and correct them and not hope vitamin E will protect you from heart attack, even if you allow the risk factors to persist. Collaborative Group of the Primary Prevention Project. Low-dose aspirin and vitamin E in people at cardiovascular risk. The Lancet. Vol 357 (January 13) Pgs 89-95. 2001.
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