Deaths Halt Part of Large Diabetes Trial
Wednesday, February 6, 2008; 12:00 AM
WEDNESDAY, Feb. 6 (HealthDay News) -- A large North American trial designed to aggressively lower the blood sugar of type 2 diabetics at risk of heart disease has been halted because of an unexpected number of deaths among those receiving the drug therapy.
Federal health officials announced Wednesday that 257 people who received the intensive therapy had died, compared with 203 in patients in a standard treatment group. But they could not pinpoint the reason for the heightened risk, and they appeared to rule out any of the diabetes drugs that were used.
A segment of the trial, called the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study, was stopped 18 months early because of the findings.
"After thoroughly reviewing the data collected to date, ACCORD investigators found that among these adults with type 2 diabetes who are at especially high risk of cardiovascular disease, a medical treatment strategy to intensively lower their blood sugar levels below the current guidelines increased the risk of death compared to standard blood sugar lowering treatment." Dr. Elizabeth G. Nabel, director of the U.S. National Heart, Lung, and Blood Institute (NHLBI), said during a teleconference.
The ACCORD trial, sponsored by the NHLBI, began in 2001 at 77 sites in the United States and Canada with the enrollment of 10,251 patients with type 2 diabetes who were at high risk for heart attack or stroke because they had at least two risk factors, including high blood pressure, high cholesterol or obesity. Those in the trial received either medications to aggressively lower their blood sugar below recommended levels, or standard treatment to control their disease.
Among the 257 deaths in the aggressive therapy group, 50 percent were due to heart attacks or other cardiovascular causes, said Dr. William Friedewald, a clinical professor of public health and medicine at Columbia University and the chairman of the ACCORD Steering Committee.
While these death rates were lower than those seen in similar groups in other studies, the NHLBI decided to follow the recommendation of the study's data safety monitoring board and stop the aggressive therapy part of the trial. Patients in that part of the trial will now receive standard care until the study ends in 2009, Nabel said.
Officials stressed that it's not clear why people in the intensive therapy group were at higher risk of death. But the researchers did not find that the combination of medications used for the trial -- and approved by the U.S. Food and Drug Administration to lower blood sugar -- was responsible for the increased risk.
The halting of the trial segment follows recent reports that one of those medications, Avandia (rosiglitazone), has been linked to an increased risk of heart attack. But Friedewalt said the drug was not responsible for the deaths.
"Because of the recent concerns raised with regard to rosiglitazone, we specifically analyzed the data to try and determine whether there was any link between this particular medication and the increased deaths we were seeing in the ACCORD intensive treatment group," Friedewald said. "At this time, we have found no link, and thus the use of rosiglitazone does not seem to explain the increased mortality."
Most of the people in the intensive treatment group were taking high doses of several medications to lower their blood sugar. Other drugs used in the trial included metformin, thiazolidinediones, insulins, sulfonylureas, exenatide, and acarbose.
Reaction to the news was generally cautious.