A drug oldie has turned out to be an unexpected goodie for treating severe heart failure, offering providers a low-cost effective treatment option for patients.
A multicenter study in 15 countries of spironolactone, a drug that blocks the action of a hormone called aldosterone, was halted early after interim results showed that in low doses the drug cut the death rate among patients with serious heart failure by 30%.
The dramatic results for the old-time drug will be published in the New England Journal of Medicine on Sept. 2. But because the findings had such extraordinary clinical significance, they were released last week on the publication's World Wide Web site, www.nejm.org.
For hospitals and health systems, the findings point to a powerful and inexpensive tool that could save the lives of tens of thousands of patients and attack one of the most common causes of admissions for heart patients.
An estimated 870,000 people were hospitalized with congestive heart failure in 1996, up 131% since 1979, according to the American Heart Association.
The drug study, led by Bertram Pitt, M.D., at the University of Michigan Medical Center, Ann Arbor, looked at about 1,700 patients with congestive heart failure, half of whom got spironolactone and half of whom took a placebo. Patients in both groups also received another class of heart drugs known as angiotensin converting enzyme inhibitors, commonly prescribed to control blood pressure and ease congestive heart failure.
Over a period of two years, spironolactone not only cut the risk of death by nearly one third but also reduced hospitalizations due to worsening heart failure by 35%.
Cardiologists were astonished by the power of the decades-old drug.
For the most part, spironolactone has not been prescribed for patients taking ACE inhibitors, out of concern that the combination could cause unhealthy buildups of potassium in the bloodstream, a potentially serious side-effect that was not seen in this study. Enlarged breasts or breast pain in men is the most common side effect in the study, reported by 10% of subjects receiving the drug.
David Malenka, M.D., a cardiologist at Dartmouth Hitchcock Medical Center, Lebanon, N.H., predicted that doctors are likely to adopt spironolactone. "A 30% reduction in mortality is a big number," he said, adding, "It's inexpensive, it's once a day, and relatively low doses seem to work."
G.D. Searle & Co., Skokie, Ill., makes the drug, marketed under the Aldactone name, for an average price of 38 cents a day. Searle provided financial support for the study. Generic versions of the drug are also available.