Currently, about five to 10 per cent of people in Toronto have type 2 diabetes. The condition is closely linked to obesity and patients are also at greater risk of cardiovascular disease (CVD). People with type 2 diabetes die of CVD at rates two to four times higher than those who do not have diabetes. They also experience more nonfatal heart attacks and strokes.
"The ACCORD study is probably one of the most important diabetes studies underway as it will answer one of the key remaining questions in diabetes therapy," said Dr. Lawrence Leiter, principal investigator; head, Division of Endocrinology & Metabolism, St. Michael's Hospital; and professor of Medicine & Nutritional Sciences, University of Toronto. "The ACCORD trial will tell us whether, through a combination of intensive treatment of not just blood sugar but also blood pressure and cholesterol levels, we can prevent the heart disease associated with diabetes."
"We have the proof that we can prevent the small vessel complications of diabetes such as diabetic eye and kidney disease," said Dr. Gillian Booth, principal investigator; clinician investigator, Division of Endocrinology and Metabolism, St. Michael's Hospital; and assistant professor, Department of Medicine, University of Toronto. "Even though 80 per cent of people with diabetes will die of heart disease, we still do not have proof that we can prevent this type of heart disease."
Type 2 diabetes, previously called adult-onset or non-insulin-dependent diabetes mellitus, is a disorder in which the muscle and fat cells do not use insulin properly. Typically associated with older age, obesity, and a family history of diabetes, it is most common in women with a history of diabetes during pregnancy, people who lead a sedentary lifestyle, and race/ethnicity. African- Americans, Hispanic/Latino Americans, American Indians (First Nation in Canada), and some Asian-Americans and Pacific Islanders are at particularly high risk for type 2 diabetes.
ACCORD is being conducted at the Diabetes Research Centre at St. Michael's Hospital and is seeking 130 adults with type 2 diabetes. In addition to blood sugar, other CVD risk factors that will be aggressively controlled in the ACCORD study are high blood pressure, high blood fats (cholesterol and triglycerides), and insulin resistance. The study is expected to go from February 2003 until June 2009. Most participants can expect their involvement to last from five-and-a-half to eight-and-a-half years.
"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.
ACCORD will test three medical treatment strategies:
- 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.
Patients with type 2 diabetes who volunteer to participate in the ACCORD study will undergo a variety of tests to determine if they are eligible. Participants selected for the St. Michael's Hospital study will receive all their diabetes treatment in the Diabetes Research Centre and will be assigned to a study group.
ACCORD study participants will receive all medication and treatments related to their study involvement free of charge. Participants in the ACCORD study will continue to see their personal physician for all their other health care needs.
Patients interested in more information can call the Diabetes Research Centre, St. Michael's Hospital at 416-867-7411.
St. Michael's Hospital is a Catholic research and teaching hospital fully associated with the University of Toronto, specializing in diabetes comprehensive care, heart and vascular disease, inner city health, trauma and neurosurgery, minimal access therapeutics and mobility disorders.
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. NHLBI press releases and other materials including information about high blood pressure, high blood cholesterol, and heart disease, are available online at www.nhlbi.nih.gov. More information about the ACCORD study can be found on the Web at www.accordtrial.org. Information about diabetes can be found on the Web at www.niddk.nih.gov.
Media interviews are available with Dr. Lawrence Leiter, principal investigator; head, Division of Endocrinology & Metabolism, St. Michael's Hospital; and professor of Medicine & Nutritional Sciences, University of Toronto.
To arrange interviews please contact:
Tracy MacIsaac, Media Relations
St. Michael's Hospital
Telephone: 416-864-5047
Pager: 416-864-5431