Spironolactone works by blocking a hormone produced by the kidneys that causes the body to retain salt a retention that causes extra fluid to build up and increases the burden on the heart. This can prove deadly to patients with congestive heart failure, a condition characterized by an inefficiently pumping heart and experienced by about 5 million Americans. "ACE inhibitors which help reduce blood pressure were also thought to counter salt retention. But the study found that the ACE inhibitors dont block the salt retention hormone as well as the old spironolactone," says Gorman. "This is an instance where people gave up on the old too soon."
Sometimes old is simply better. Medical researchers learned that truth after revisiting the benefits of a 30-year-old drug, once used to treat congestive heart failure but tossed aside when new medications came along. The medicine, spironolactone, fell into disfavor when drugs such as ACE inhibitors were introduced, says TIME medical columnist Christine Gorman. But in a study released on Monday, researchers revealed that spironolactone, when added to the standard new drug treatments, can reduce congestive heart failure deaths and hospitalizations by about one third. The results were so dramatic that the study was cut short by one year and the findings published on the web site of the New England Journal of Medicine before the scheduled September publication date.