February 2003 - A major new study will test the best approaches to lowering the risk of heart disease and stroke in adults with type 2 diabetes. The Action to Control Cardiovascular Risk in Diabetes (ACCORD) study is being sponsored by the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health (NIH). The National Institute on Diabetes and Digestive and Kidney Diseases (NIDDK), another part of NIH, is providing additional support for the study.
The ACCORD clinical trial seeks to enroll 10,000 adults with type 2 diabetes in 70 clinics around the United States and Canada. All eligible participants will be in the blood sugar control part of the trial. Patients will be randomly assigned to a treatment regimen involving either aggressive or standard control of blood sugar. Then, depending on their blood pressure and cholesterol levels, they will be assigned to either a high blood pressure or high blood fats (cholesterol and triglycerides) part of the study.
"This is the first large-scale study in patients with diabetes to test the effects of intensively controlling blood sugar along with aggressive control of blood pressure and lipids," said NHLBI Director Claude Lenfant, M.D. "Given the serious consequences of type 2 diabetes, we expect that the ACCORD study will meet its overall goal to address this significant public health challenge," added Dr. Lenfant.
Currently, about 17 million Americans have diagnosed diabetes and more than 90 percent of them have type 2 diabetes. The number of people with this form of diabetes, formerly known as adult onset or non-insulin dependent diabetes, is growing rapidly. By 2050, the number of Americans with diagnosed diabetes is projected to increase by 165 percent to 29 million, 27 million of whom will have the type 2 form. Cardiovascular disease (CVD) is the leading cause of death in people with type 2 diabetes, who die of CVD at rates 2 to 4 times higher than those who do not have diabetes. They also experience more nonfatal heart attacks and strokes.
Type 2 diabetes is associated with older age and is more common in those who are overweight or obese and have a family history of diabetes. Women with a history of diabetes during pregnancy, adults with impaired glucose tolerance, people with a sedentary lifestyle, and members of a minority race/ethnicity also are at greater risk for type 2 diabetes. African Americans, Hispanic/Latino Americans, American Indians, and some Asian Americans and Pacific Islanders are at particularly high risk for type 2 diabetes.
ACCORD involved an initial and successful vanguard phase of 1, 184 participants. The results from that phase were used to refine the current protocol. The ACCORD study is expected to go from February 2003 until June 2009. Most participants can expect their involvement to last from 5.5 to 8.5 years.
The three strategies tested in ACCORD will be:
- Blood sugar. ACCORD will determine whether lowering blood glucose to a goal closer to normal than called for in current guidelines reduces CVD risk. The study will determine effects on CVD of that level compared with a level that is usually targeted.
- Blood pressure. Many people with type 2 diabetes have high blood pressure (HBP). The blood pressure part of the trial will determine the effects of lowering blood pressure in the context of good blood sugar control. ACCORD will determine whether lowering blood pressure to normal (<120mmHg systolic) will reduce CVD risk better compared to a usually-targeted level in current clinical practice, i.e., below the definition of hypertension (<140mmHg systolic).
- Blood Fats. Many people with diabetes have high levels of LDL ("bad") cholesterol and triglycerides, as well as low levels of HDL ("good") cholesterol. ACCORD participants who are selected for this part of the trial will be assigned to an intervention that improves blood fat levels. This part of the study will look at the effects of lowering LDL cholesterol and blood triglycerides and increasing HDL cholesterol compared to an intervention that only lowers LDL cholesterol, all in the context of good blood sugar control. A drug from a class of drugs called "fibrates" will be used to lower triglycerides and increase HDL cholesterol, whereas a drug from the class of drugs called "statins" will be used to lower the LDL cholesterol.
"The ACCORD trial is extremely important for patients and their health-care providers," said Denise Simons-Morton, M.D., ACCORD project officer. "The study will help determine the best ways to treat diabetic patients to prevent the most common and serious consequence of diabetes, which is cardiovascular disease," she said.
All ACCORD participants will receive their blood sugar treatment from the study. Based on the additional part of the trial they are assigned to, participants will also receive their cholesterol or high blood pressure care from the study. Study participants will receive all medication and treatments related to the study free of charge. Patients who are selected and consent to participate in the ACCORD study will continue to see their personal physician for all their other health care.
"We have the potential to change the fundamental approach to the care of people with type 2 diabetes," said Dr. Jeffrey Probstfield, member of the ACCORD Steering Committee, Professor of Medicine (Cardiology), University of Washington. "Participants in the study can feel assured that they will be helping millions of adults who have challenges to cardiovascular health much like their own," he said.
NHLBI is part of the National Institutes of Health (NIH), the Federal Government's primary agency for biomedical and behavioral research. NIH is a component of the U.S. Department of Health and Human Services.