The news coming out of the American College of Cardiology's annual conference this week was enough to make anyone's heart skip a beat. Two of the field's most promising high-tech therapies for cardiovascular disease—stents that keep arteries open and experimental drugs that boost levels of "good cholesterol"—were found to be far less effective than doctors had hoped. Meanwhile, other researchers announced that a daily mild aspirin, a treatment that's as low-tech as it gets, could reduce some women's risk of heart disease and stroke, even though previous studies had suggested otherwise. What to make of all the surprises?
The results of the stent study were probably the most unexpected—one doctor at the meeting told reporters he was "incredulous" upon seeing them. But they're real, and they fit into a growing body of research suggesting that the tiny metal tubes aren't the cure-all they were touted to be when they hit the market 13 years ago. In the study, published this week in the New England Journal of Medicine, some patients with chronic coronary artery disease were treated with stents as well as a cocktail of drugs that affect the arteries, including cholesterol-lowering statins. A second group took only the drugs. The stent group did see some short-term benefits—they had better blood flow to the heart and fewer noticeable symptoms of heart disease, such as chest pain and difficulty breathing. But in the long run, five years after treatment, both groups turned out to have fared equally well. The patients with stents didn't live any longer on average, nor did they have fewer heart attacks.
The new study doesn't mean stents should be taken off the market; they can still help millions of patients, particularly those who don't respond well to drugs. But it does suggest that doctors need to start thinking about them differently. Stents are extremely popular (they've been implanted into six million people worldwide), but they're expensive, costing about $2,200 per device, plus another $25,000 for the procedure to place them. Doctors will now have a more difficult time arguing that such a costly intervention is justified, especially for patients with mild cases of heart disease who might do just as well on drugs alone. And for seriously ill patients, some docs may now be more likely to advocate bypass surgery instead. It's a riskier and much more invasive procedure, but, unlike stents, it's proven to prolong life.
That wasn't the end of the conference's bad news for patients with plaque-hardened arteries. Several other studies presented Monday suggested that enhancing patients' levels of "good cholesterol," or high-density lipoprotein (HDL)—long thought to be the next big therapy for atherosclerosis—did not, in fact, cut down on plaque. Doctors had been hoping to help patients with experimental drugs called torcetrapib, LY518674, and CSL-111. The drugs did boost patients' levels of good cholesterol to unheard-of levels. Unfortunately, they didn't have the desired effect on patients' overall health. No one understands why, but the increase in HDL didn't translate into a significant decrease in plaque in any of the trials. Patients on the third drug, CSL-111, did seem to score better on tests of heart function. But their arteries were just as blocked up as they'd always been.
All three drugs also have some side effects that may be dangerous. Pfizer stopped studying torcetrapib in December because it raises blood pressure; in previous studies, several patients died while on the drug. LY518674 increases "bad cholesterol" along with the good kind. And part of the trial of the third drug, CSL-111, had to be stopped midway through, because patients taking high doses developed problems with liver function. Some doctors still think boosting HDL levels will turn out to be a viable treatment for atherosclerosis. But judging by the new studies, it will be a long time before drugs are ready for widespread use.
Even the good news coming out of the meeting wasn't wholly positive. Researchers at Harvard announced that women who had been taking low or moderate daily doses of aspirin for five years or more were 38 percent less likely to die of heart disease or stroke. Older women and those with other risk factors for heart disease got the biggest benefit. But counter intuitively, women who took a high dose of aspirin daily saw the opposite effect: they were 43 percent more likely to die of stroke than those who took no aspirin at all. Some cardiologists at the conference questioned the study's methodology. The data presented Monday, which were also published in the Archives of Internal Medicine, came from the Nurses' Health Study, which has yielded questionable research before. Most dangerously, it suggested for years that hormone replacement therapy lowered heart disease risk, when later studies found that it actually increased the risk. An editorial accompanying the new data on aspirin pointed out that other large studies have failed to find the positive effects presented Monday. Docs were also quick to say that women (and men, for that matter) should consult their doctors before taking any medications, even those as safe and mild as low-dose aspirin. The best medicine for heart disease, they added, is still a healthy lifestyle—and that shouldn't surprise anyone.