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Thursday, December 19, 2002Compared to participants who took the diuretic, the ACE inhibitor group had, on average, about two points higher systolic blood pressure, the top number in the blood pressure reading. Blacks in the group had a systolic blood pressure four points higher. There was a 15 percent higher risk of stroke overall for the ACE inhibitor group and a 40 percent higher risk for blacks. The risk for heart failure among all groups was 19 percent higher, and the risk for hospitalization or treatment for the chest pains of angina was 11 percent higher. Further, the risk of needing a coronary bypass operation or angioplasty was 10 percent higher. Compared with participants who took the diuretic, the calcium channel blocker group had, on average, a systolic blood pressure about one point higher and a 38 percent higher risk of developing heart failure Although the press have been making diuretics out to be superior to the newer drugs, the truth is they’re really about the same. The mean blood pressure readings were the same for the diuretics and the newer drugs. (They differed by only two to four points, not a clinically significant difference at all). The incidence of heart attacks and other illnesses were basically the same, too, varying by only one or two percentage points. This does, however, have quite a bit of significance for treatment. Many physicians have been led down the primrose path of believing that ACE inhibitors are the superior drug. Not, as the Times suggests, because we’ve been brainwashed, but because of theoretical advantages of ACE inhibitors in heart patients. These theories have been backed up by studies. It is true that those studies showed marginal improvement, and that their authors gave them the best possible spin they could, but they were published in prestigious medical journals. And when a study gets published in a prestigious journal, the theory gets transformed into gospel. (Which is a rant for another day) Now, we have data that calls that theory into question. In the real world, the newer drugs have no advantage over the old drugs, although they cost a much prettier penny. Lisinopril, the ACE inhibitor used in the study costs from $12 to $25 a month , while chlorthalidone, the diuretic used costs $8. There are still some conditions, though, in which an ACE inhibitor would be a better choice. They slow the progression of kidney disease in diabetics, for example. And they can improve the function of a failing heart. But for the average, uncomplicated case of high blood pressure, there’s no good reason to avoid a trial of the cheaper drugs. ADDENDUM: Derek Lowe has the medicinal chemist’s view here. And Statins Aren’t So Great, Either: The same study that looked at diuretics also looked at the value of Pravachol, a cholesterol-lowering drug, which along with others in its class has been hailed by some as the miracle drug of the late twentieth century . The study compared mortality rates in people with high blood pressure and high cholesterol who were treated with diet versus those who were treated with the cholesterol-lowering drug. The statins have earned their all-star status on the basis of studies that show they improve the incidence of heart attacks by a few percentage points. If you look at the rates of death, however, they don’t give any advantage: Pravastatin did not reduce either all-cause mortality or CHD significantly when compared with usual care in older participants with well-controlled hypertension and moderately elevated LDL-C. The results may be due to the modest differential in total cholesterol (9.6%) and LDL-C (16.7%) between pravastatin and usual care compared with prior statin trials supporting cardiovascular disease prevention. Apologists for statins say that the results are the same because many in the diet group ended up on statins during the study, and many on statins had to stop them. Why did some in the diet group end up on statins? Because giving statins to patients with other conditions such as heart disease or diabetes has become the standard of care in this country - despite the marginal benefits of doing so. And why did some of those taking the drugs stop? Side effects. However, if you look at the numbers, you can see that these subgroups were in the minority, and likely to have had little effect on the outcome. And yet, there are those who just can’t, or won’t, give up on the statins as saviours point of view: "Physicians might be tempted to conclude that this large study demonstrates that statins do not work," according to Dr. Richard C. Pasternak, of Harvard Medical School in Boston, Massachusetts. "However, it is well known that they do," he concludes in an editorial that accompanies the study. What may have happened, according to Pasternak, is that the drugs may not be as effective in ordinary settings as they are in clinical trials where participants are carefully selected and followed closely. Pasternak has served as a consultant to or on the advisory boards of several pharmaceutical companies, including Bristol-Myers Squibb. In addition, he has received funding from Merck-Medco and has served on the speakers bureau for several drug makers. It isn’t well known that they work. What is well-known is that they provide a marginal benefit (Click here, here, here, and here for the studies, and here for my rant) at great financial costs - at least for patients and insurance companies, if not for Dr. Pasternack, and his colleagues. And most of us live and work in the real world, not in the rarefied atmosphere of a clinical study. ADDENDUM: RangelMD gives the argument in favor of statins here. posted by Sydney on 12/19/2002 08:19:00 AM 0 comments 0 Comments: |
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