More About Estrogen
Levels of estradiol were not associated with the risk of cardiovascular disease in hormone users or nonusers in a report from the Women’s Health Study that appears in this week’s issue of the journal Circulation (Circulation. 2003;108:1688–1693). Researchers noted lower sex hormone–binding globulin and a higher free androgen index in women who did not use hormone therapy and had a cardiovascular event, but this was not independent of body mass index and other cardiovascular risk factors.
This nested case-control study matched 200 women in the Women’s Health Study who developed cardiovascular disease to 200 who did not. Women were matched according to age, smoking, and postmenopausal hormone therapy status. Researchers measured testosterone, estradiol, and sex hormone–binding globulin levels, and they calculated the free androgen and free estradiol indices and the free androgen index/free estradiol index ratio for each research subject. There were no significant differences in hormones or sex hormone–binding globulin levels among women on hormone therapy who developed cardiovascular disease and those who did not. However, the researchers wrote: “Larger studies of the relationship between hormone levels and risk of CVD [cardiovascular disease] in women who are not using exogenous hormones are necessary to determine whether androgenicity is an independent cardiovascular risk factor in postmenopausal women.”
Adding Clopidogrel Helps—CURE
Adding clopidogrel to aspirin is beneficial in patients with acute coronary syndromes, regardless of the dose of aspirin, said researchers from the CURE (Clopidogrel in Unstable angina to prevent Recurrent Events) study in a report in this week’s issue of the journal Circulation (Circulation. 2003;108:1682–1687).
In the CURE study, 12 562 patients with acute coronary syndrome who were already using aspirin in dosages from 75 mg to 325 mg daily were randomized to receive clopidogrel or placebo for as long as a year. Adding clopidogrel to the daily regimen reduced cardiovascular mortality, myocardial infarction, and stroke across the board. Among those taking less than 100 mg of aspirin daily, 8.6% who received clopidogrel suffered one of the listed major adverse cardiovascular events, compared with 10.5% of those who received placebo. In those taking 101 to 199 mg of aspirin, 9.5% of those taking clopidogrel died, compared with 9.8% of those on placebo. Of those who took more than 200 mg of aspirin daily, 9.8% of those also on clopidogrel died, compared with 13.6% of those on placebo. Increasing the aspirin dose increased the incidence of major bleeding, whether the patient was taking clopidogrel or not.
The researchers concluded, “Our findings suggest that the optimal daily dose of aspirin may be between 75 and 100 mg, with or without clopidogrel.”
Sirolimus-Eluting Stents Win Again
Sirolimus-eluting stents are an effective treatment in patients with complex coronary lesions because they reduce the rates of restenosis and other stent-related problems, said researchers in the SIRIUS (SIRolImUS-Eluting Stent in De Novo Native Coronary Lesions) trial in the October 2, 2003, issue of The New England Journal of Medicine (N Engl J Med. 2003;349:1315–1323).
This randomized, double-blind trial compared a sirolimus-eluting to a standard stent in 1058 patients recruited at 53 centers in the United States. All the patients had a newly diagnosed lesion in a native coronary artery. The patients had a high frequency of diabetes (26%) and long lesions (an average 14.4 mm). Their vessels were also small in diameter, measuring on average 2.8 mm.
After 270 days of follow-up, 21% of patients who had received the standard stent had suffered death from cardiovascular causes or myocardial infarction or had undergone revascularization of the target lesion, compared with only 8.6% of patients who had received the sirolimus-eluting stent. A reduction in the need to revascularize the target lesion was the major factor in the reduction, said the researchers, who were led by Jeffrey W. Moses, MD, from the Lenox Hill Heart and Vascular Institute of New York, NY. They also found a reduction in neointimal hyperplasia among the patients who received the drug-eluting stent.
The researchers concluded, “The results of our clinical trial demonstrate that the sirolimus-eluting stent has achieved the delicate balance of preserved safety and improved efficacy and thus has the potential to alter the course of coronary therapy in the future.”
In an accompanying perspective (N Engl J Med. 2003;349:1307–1309), Andrew R. Marks, MD, of the Department of Physiology and Cellular Biophysics, Center for Molecular Cardiology, Columbia University College of Physicians and Surgeons, New York, wrote, “As sirolimus-coated stents move into general use, it is likely that the rate of restenosis will be higher than that shown in the SIRIUS trial. . . . Some questions remain. For example, how long will the inhibitor effects of sirolimus persist? Will oral (systemic) sirolimus therapy result in a degree of inhibition of in-stent restenosis similar to that achieved with the drug-eluting stents? And will there be subgroups of patients (such as those with diabetes) who are more resistant than others to the therapeutic actions of sirolimus? Further understanding of the basic mechanisms by which sirolimus inhibits in-stent restenosis will help to address these questions.”
Women’s Stroke Risks Misunderstood Worldwide
An international survey reveals that physicians around the world underestimate the risk of stroke in women.
The survey, released on World Heart Day, showed that 6 of 10 physicians believe that men are more likely to die of stroke than are women. In fact, 11% of women who suffer stroke die from the event, compared with 8% of men, said officials with the World Heart Federation. The Global Reality of Attitudes on Stroke Prevention and Hypertension (GRASP) study was sponsored jointly by the World Heart Federation and Merck & Co, Inc, to ascertain physicians’ perceptions on hypertension management. The survey results were compiled from 825 primary care physicians in 11 countries.
“While most people think of cardiovascular disease as a man’s problem, the truth is that both sexes suffer just about equally, but for a variety of reasons cardiovascular conditions, such as stroke, are more often fatal in women than in men,” said Janet Voûte, Chief Executive Officer of the World Heart Federation, in a released statement.
The GRASP survey showed that physicians understand the relationship between hypertension and stroke. In fact, 70% of physicians believed that stroke could be prevented by controlling blood pressure.
“It is encouraging that physicians are concerned about preventing stroke in hypertensive patients,” said Massimo Volpe, MD, Professor of Cardiology at the University of Rome. “Now we need to ensure that they also appreciate that women are just as much at risk of having a stroke as men. Therefore, women as well as men need to be evaluated and treated appropriately, using evidence-based medicine, to reduce their risk of having a stroke.”