Glucose-Control Arm of ACCORD Trial Halted Early

Increased mortality associated with aggressive glucose reduction raises safety concerns.
The National Heart, Lung, and Blood Institute has announced the early termination of one treatment arm of the ongoing Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial because of an increased risk for death among patients assigned to intensive glucose-lowering therapy (press release, February 6, 2008). The 5128 participants (at 77 North American sites) randomized to treatment aimed at reducing HbA1c levels to <6.0% will now be treated to a target HbA1c level of 7.0% to 7.9%, the same as participants in the control group. Two concurrent trials of management strategies for cholesterol and hypertension will continue as planned.
The Data and Safety Monitoring Board of ACCORD recommended stopping intensive glucose-lowering therapy after it found that 257 patients in that group had died, compared with 203 in the standard therapy group: a difference of 3 per 1000 participants per year during a mean of about 4 years of treatment. Preliminary analyses have found no association of the mortality increase with any specific drug or drug combination. All participants in the ACCORD study have type 2 diabetes and either coronary heart disease or at least two risk factors for adverse cardiovascular events.
Comment: The ACCORD trial was inspired by previous research that found a link between tightly controlled blood sugar and reduced risk for many complications of type 2 diabetes. Why an increased risk for death was associated with tight glucose control in this trial remains unclear. These results raise questions about intensity of and appropriate targets for glucose-lowering treatment in patients with type 2 diabetes, but they do not alter current guidelines or treatment strategies for most diabetic patients.
— Joel M. Gore, MD
Published in Journal Watch Cardiology February 13, 2008