Deaths Prompt Halt in Diabetes Study
Study of Intensive Treatment of Diabetes Curtailed Because of Increased Death Rates
Feb. 6, 2008 -- Researchers abruptly halted part of a major diabetes trial Wednesday because of increased death rates in patients who got intensive treatment to lower their blood sugar.
Researchers say they do not know the reasons for the deaths, which occurred in type 2 diabetes patients getting intensive treatment with multiple drugs for blood pressure, high cholesterol, and blood sugar. Parts of the trial evaluating less intensive treatment would continue, they say.
"We did not anticipate the findings and in that sense we were surprised," says Elizabeth G. Nabel, MD, director of the National Heart, Lung and Blood Institute, an arm of the National Institutes of Health that is leading the trial.
The trial, known as the "Action to Control Cardiovascular Risk in Diabetes" trial, or ACCORD, was started in 2001 to test whether intensively lowering blood sugar in high-risk type 2 diabetes patients cuts their risk of cardiovascular events like heart attacks and strokes.
But part of the 10,251-person trial was stopped after researchers saw 257 deaths in the group of patients undergoing intensive treatment to lower blood sugar control down to levels below current recommendations. That was compared with 203 patients who died while in standard, less intensive treatment.
The difference added up to three deaths per 1,000 patients over four years, investigators say.
Intensive Blood Sugar Treatment
Researchers have long theorized that more aggressive blood sugar treatment would help high-risk type 2 diabetes patients avoid cardiovascular problems. Other studies have shown that blood glucose control lowers the risk of eye, nerve, and kidney complications that often follow diabetes.
"We obviously were surprised. We were hoping for a positive outcome, but the reason we do this research is that we don't know that," says William T. Friedewald, MD, a professor of medicine at Columbia University and chairman of the study's steering committee.
The study, conducted at 77 centers in the U.S. and Canada, divided patients into two main groups. One group got standard diet, exercise, and drug treatment designed to lower a measurement of blood sugar control called hemoglobin A1c to between 7% and 7.9%. A second group got intensive treatment designed to drop A1c even further to under 6%, the levels seen in most adults without diabetes.