MONDAY, Dec. 8, 2003 (HealthDayNews) -- People with mild heart failure and diabetes can safely use two new drugs that improve the body's response to insulin if they are monitored carefully for signs of potentially severe side effects, says a recommendation issued jointly by the American Heart Association and the American Diabetes Association.
The drugs, Avandia and Actos, are members of a family called thiazolidinediones (TZDs). A third TZD, Rezulin, was removed from the American market by the U.S. Food and Drug Administration (FDA) because of reports it was causing serious liver damage in some patients.
"Liver problems are not an issue" in the new recommendations, says Dr. Vivian Fonseca, a professor of medicine at Tulane University and an American Diabetes Association representative on the expert panel that prepared the report. "People with diabetes have a certain amount of liver abnormalities, and the rate of these does not appear different for those who take these drugs."
Instead, the recommendations are being issued because of scattered reports that the TZDs can lead to development or progression of congestive heart failure, a potentially fatal condition in which the heart progressively loses its ability to pump blood, Fonseca says.
"We are telling people that there is no clear evidence that these diabetes drugs cause heart failure," he says. "We think that the risk is quite low. We still think that patients with mild to moderate heart failure can use these drugs, if they go slow and are monitored."
The responsibility falls on both doctors and patients, says Dr. Richard W. Nesto, chairman of the department of cardiovascular medicine at the Lahey Clinic in Burlington, Mass., an American Heart Association member of the panel and lead author of the joint statement.
"In patients with a history of mild heart failure or risk factors for heart failure, there should be a gradual buildup of the dose," Nesto says. "The patient should be alerted to report back to the doctor if there is a weight gain of more than six pounds, swelling of the legs, and other symptoms of heart failure, such as shortness of breath or fatigue."
There is nothing unusual about these recommendations, Nesto says. They are similar to precautions taken with other drugs that can increase the risk of heart failure by causing the body to retain more fluid, such as calcium channel blockers, steroids and nonsteroidal anti-inflammatory drugs, he says.
"This is just good medical practice, not a special set of rules," Nesto says.
The consensus statement says that people with advanced heart disease or severe congestive heart failure should avoid TZDs, and that the drugs should be used in people whose hearts have impaired pumping ability "if no other means of glucose control has worked."
"In those extreme cases, the drugs should be started at low doses," the statement says.
Overall, Nesto says, the TZDs are "a new and valuable addition to the armamentarium of doctors trying to gain better sugar control in diabetes patients."
The studies that led to FDA approval of the drugs included patients with the two milder classes of heart failure, stages 1 and 2. New studies now under way include some patients with stage 3 heart failure, but not patients with the most severe form of the condition, stage 4, Nesto says.
There have been relatively few reports of TZDs causing or accelerating heart failure, he says, but those reports "helped trigger the need to look at this issue in an official way." The ongoing studies are expected to clarify the risk, Nesto says.
The recommendations are being published in the Dec. 9 issue of Circulation and the January issue of Diabetes Care.
More information
A comprehensive overview of heart failure and what can be done about it is available at the American Heart Association, while the American Diabetes Association has a page on oral diabetes drugs.
