FRIDAY, Sept. 15, 2006 (HealthDay News) -- The drug Avandia, approved for the treatment of type 2 diabetes, may help prevent the disease from developing in high-risk individuals, Canadian researchers report.
Use of Avandia (rosiglitazone) over three years cut the risk for type 2 diabetes by about two-thirds, the study found.
"Balancing both the benefits and risks suggests that for every 1,000 people treated with rosiglitazone for three years, about 144 cases of diabetes will be prevented," wrote a team from McMaster University in Hamilton, Ontario.
The Diabetes Reduction Assessment with Ramipril and Rosiglitazone Medications (DREAM) trial offered up less heartening results on the heart drug Altace (ramipril), however.
Despite earlier trials suggesting the ACE inhibitor might help prevent type 2 diabetes, the DREAM investigators found it did not forestall the disease in at-risk patients, although it did have some modest effect in lowering blood sugar.
The DREAM researchers announced their findings Friday at a meeting of the European Association for the Study of Diabetes, in Copenhagen. The results of the Avandia arm of the study are also published in the Sept. 15 online edition of The Lancet. The results of the Altace arm of the study will appear in the Oct. 12 print edition of the New England Journal of Medicine; the findings were released Friday, to coincide with the presentation in Copenhagen.
The DREAM trial received funding from the Canadian Institute for Health Research, as well as from drug makers GlaxoSmithKline, the maker of Avandia, and Sanofi-Aventis and King Pharmaceuticals, the makers of Altace.
More than 90 percent of diabetics have the type 2 form of the disease. Type 2 diabetes generally begins in the adult years, and is often due to being overweight or obese. In type 2 diabetes, either the body does not produce enough insulin or the cells ignore the insulin, a hormone that converts blood sugar to energy for cells.
According to U.S. Centers for Disease Control and Prevention, more than 20.8 million Americans have type 2 diabetes and 41 million are at risk of developing the condition, due in large part to the upsurge in obesity.
The U.S. Food and Drug Administration approved Avandia to treat type 2 diabetes in 1999. The drug is part of the thiazolidinedione family of medications, which improve the body's sensitivity to insulin and lower blood sugar levels.
But could the drug also prevent the disease in people at risk? In the DREAM trial, the Canadian team randomly assigned nearly 5,300 adults from clinics in 21 countries to get 8 milligrams of Avandia or a placebo daily for three years. All of the participants were at high risk of developing type 2 diabetes, having already shown signs of poor blood-sugar control.
In addition, the researchers emphasized the importance of a healthy diet and lifestyle in preventing type 2 diabetes.
Over the course of the trial, 280 people (12 percent) taking Avandia went on to develop type 2 diabetes compared with 658 people (26 percent) who received the placebo, the researchers report.
The researchers did note a small increase in risk of nonfatal heart failure among those taking Avandia, compared with those receiving placebo, the investigators found. This increase in risk would amount to about four or five extra cases of congestive heart failure for every 1,000 people who took the drug.
In the studies' other arm, at-risk patients received up to 15 milligrams daily of Altace, a blood-pressure medication, or a placebo for three years. The researchers found no significant difference between the two groups in either deaths or incidence of diabetes.
Patients who took Altace did tend to have better blood sugar control, but the "absolute difference" in blood sugar levels between the two groups was small, the researchers noted.
Those results were a disappointment, experts said, since prior research had suggested Altace or other ACE inhibitors might help prevent diabetes.
"Given the primary findings of the DREAM trial, ramipril cannot be recommended for the prevention of type 2 diabetes," Drs. Julie Ingelfinger and Caren Solomon, both of Harvard Medical School, wrote in a related NEJM editorial. They noted, however, that patients who take the drug for other reasons may gain added benefit in terms of lowered blood sugar.
Experts were more optimistic about Avandia, but offered up some caveats.
"Avandia works in preventing diabetes, but the downside is that it causes people to retain fluid and exacerbates heart failure," Dr. Stuart Weiss, an endocrinologist at New York University Medical Center, said in a prepared statement.
Overall, however, Avandia did seem effective in lowering diabetes risk. "The results of this study suggest that the addition of rosiglitazone to basic lifestyle recommendations substantially reduces the risk of developing diabetes by about two-thirds," the Canadian team wrote. They say the drug's preventive effect "could be as, or more, effective and sustained than previously reported lifestyle approaches alone."
But that worries one expert, who is concerned that at-risk individuals will forego healthy diets and exercise in favor of a pill.
"I am horrified with the diabetes exploding around us," said Dr. Larry C. Deeb, president for medicine and science of the American Diabetes Association.
"The question is whether diabetes prevention is becoming a pharmacological intervention rather than diet and exercise," Deeb said. "I hope nobody believes that you replace one with the other. The other side is, it doesn't look like Americans, Europeans, Japanese or Indians are leaping off the couch with any abandon."
"Regrettably, we as a society would rather take pills rather than walk, run, play and eat healthy," Deeb said. "But when you see the ravages the disease takes on people-- anything you can do to prevent it is worth doing," he said.
Weiss agreed. While Avandia can help ward off type 2 diabetes, "the drug will not absolutely prevent diabetes," he said. "There is no drug that cannot be overwhelmed by a bad diet."
There's much more on type 2 diabetes at the American Diabetes Association.