August 1, 2006
Birmingham, Ala. – Digitalis, the oldest and one of the least expensive heart medications, may help reduce the risk of hospitalizations due to worsening heart failure in patients with diastolic heart failure, contrary to a widely held belief that the drug should not be used in that group of patients. The findings, published in the journal Circulation, suggest that digitalis may reduce the risk of heart failure hospitalization in the short term with no increase in mortality for those with diastolic heart failure.
About half of the 5 million heart failure patients in the United States have diastolic heart failure, in which the heart does not fully relax, limiting the amount of blood the ventricle will accept – as opposed to systolic heart failure, when the heart muscle is too weak to effectively pump blood throughout the body. Recent studies suggest that the morbidity and mortality in diastolic heart failure may be very similar to systolic heart failure. Yet, diastolic heart failure patients have often been excluded from clinical trials, and little is known about evidence-based therapy for these patients. Diastolic heart failure has only recently been identified as a separate condition from the systolic form of the disease.
“Digitalis has been shown to be quite effective in reducing heart failure hospitalizations for patients with systolic heart failure receiving concurrent therapy with ACE inhibitors and diuretics,” said Ali Ahmed, M.D., M.P.H, assistant professor of medicine at UAB (University of Alabama at Birmingham) and lead author of the study. “However, there is little known of its effects on diastolic heart failure, and this is the first study to suggest that digitalis may reduce the risk of heart failure hospitalization without increasing mortality in diastolic heart failure patients receiving ACE inhibitors and diuretics.”
Ahmed says that heart failure is the number one cause of hospitalization in patients over age 65, and heart failure hospitalization is an important outcome in older adults with heart failure, many of whom have diastolic heart failure.
Ahmed and collaborating researchers at 10 other institutions, including the National Heart, Lung and Blood Institute, one of the National Institutes of Health, examined data drawn from 988 patients with diastolic heart failure enrolled in the DIG ancillary trial in the U.S. and Canada in the early 1990s. Patients with diastolic heart failure were treated with either digitalis or a placebo and followed for a mean duration of about three years.
“These findings indicate that digitalis is safe and may be useful in reducing heart failure hospitalization in symptomatic diastolic heart failure patients receiving ACE inhibitors and diuretics. These findings are important, as there are no other drugs of proven benefit for patients with diastolic heart failure,” Ahmed said.
The research was funded by the National Heart, Lung and Blood Institute in cooperation with the Department of Veterans Affairs Cooperative Studies Program. Glaxco Welcome provided the study drugs.
Co-investigators include Michael Rich, M.D., Washington University; Jerome Fleg, M.D., National Heart, Lung and Blood Institute; Michael Zile, M.D., Medical University of South Carolina; James Young, M.D., Cleveland Clinic Foundation; Thomas Love, Ph.D., Case Western Reserve University; Wilbert Aronow, M.D., New York Medical College; and Kirkwood Adams, M.D., University of North Carolina at Chapel Hill.