Less Costly Diuretics More Effective than Expensive Drugs at Treating Hypertension, Study Finds

Diuretics, the least expensive treatment for high blood pressure, are more effective than newer, more expensive classes of drugs, according to findings from a recently released federal study, which could have "major effects" on the cost of treating hypertension, the Washington Post reports (Brown, Washington Post, 12/18). The study, published in today's Journal of the American Medical Association, began in 1994 with 42,418 volunteers ages 55 and older who had high blood pressure and at least one other heart disease risk factor (Altman, New York Times, 12/18). Participants were randomly assigned to take one of three drugs: chlorthalidone, a diuretic; amlodipine, a calcium channel blocker sold by Pfizer under the brand name Norvasc; or lisinopril, an ACE inhibitor sold by Merck as Prinivil and by AstraZeneca as Zestril. After five years, there was no difference in mortality rates among the three groups. However, participants who took diuretics had slightly lower rates of congestive heart failure than those taking the calcium channel blocker, and slightly lower rates of stroke, angina and heart procedures than those taking the ACE inhibitor (Washington Post, 12/18).

About 50 million U.S residents have high blood pressure, and nearly half of those patients spend about $15.5 billion annually on hypertension treatments. The study's researchers concluded that wider use of diuretics could save patients and insurers more than $1 billion annually. However, the use of diuretics, once the "mainstay" of hypertension treatment, has "plummeted" with the introduction of newer and costlier name-brand drugs, the Times reports (New York Times, 12/18). A 1995 study found that the use of diuretics declined from 56% of all antihypertensive prescriptions in 1982 to 27% by 1992. "We find out now that we've wasted a lot of money. In addition, it has probably caused harm to patients," Dr. Curt Furberg, one of the authors of the study, said. Some industry analysts said yesterday the results of the study are unlikely to have much effect on sales of newer classes of hypertension treatments because pharmaceutical companies will continue to market their drugs as additional treatments for patients who need more than one treatment to control high blood pressure. Drug industry executives agreed, adding that some patients "cannot tolerate" diuretics (Petersen, New York Times, 12/18). The following broadcast programs reported on the study:

• ABCNews "World News Tonight:" A video excerpt of the segment is available online in RealPlayer (McKenzie/Johnson, "World News Tonight," ABCNews, 12/17).
  
• CBS' "Evening News:" A video excerpt of the segment is available online (Kaledin, "CBS Evening News," CBS, 12/17).
  
• NPR's "All Things Considered:" The full segment is available online in RealPlayer (Knox, "All Things Considered," NPR, 12/17).