On February 6, 2008, the National Heart, Lung, and Blood Institute, which sponsors the ACCORD (Action to Control Cardiovascular Risk in Diabetes) Trial, announced that it has stopped the intensive blood glucose (sugar) control sub-study due to safety concerns. The trial randomized patients with diabetes and vascular disease or multiple cardiovascular risk factors to an intensive treatment program targeting normal blood glucose values and an A1C less than 6 percent or a standard treatment program with an A1C between 7 percent and 7.9 percent. The intensive participants in ACCORD are now being switched to the standard treatment program because of an increased death rate in the intensive treatment program (14 deaths per 1000 patients per year versus 11 per 1000 patients per year in the standard treatment program; a difference of 0.3 death per100 patients per year).
The American Diabetes Association strongly encourages people with diabetes not to alter their course of treatment without first consulting with their health care team. The American Diabetes Association continues to encourage good control of blood glucose for the management of diabetes and its complications.
The American Diabetes Association has prepared the following question-and-answer sheet to provide you with more information on this matter.
In light of the ACCORD trial announcement, will the ADA changes its guidelines for blood glucose control, as measured by the A1C test?
Based on the preliminary findings from the ACCORD Trial, the ADA will not, at this time, revise its current guidelines for glycemic control. ADA’s current guidelines for diabetes treatment recommend maintaining an A1C level of less than 7 percent for most people with type 2 diabetes. This recommendation is based on the proven significant benefits of blood glucose control in preventing eye, kidney, and nerve complications.
The Association’s guidelines also state that treatment should be tailored to the individual patient and that for some people with diabetes, intensive glucose control may not be warranted. Of note, the American Diabetes Association (in its Standards of Medical Care) states: “Less stringent A1C goals may be appropriate for patients with a history of severe hypoglycemia, patients with limited life expectancies, children, individuals with comorbid conditions, and those with longstanding diabetes and minimal or stable microvascular complications.”
Is there a level of blood glucose control that is dangerous?
There is no data to suggest that there is any one specific level or threshold of blood glucose control that is dangerous for all people with diabetes. Certainly, some adverse complications such as hypoglycemia can occur as blood glucose levels are lowered with insulin or one type of oral medication (sulfonylureas). However, the preliminary results from the ACCORD trial do not establish a particular threshold of A1C that is associated with an adverse event. Also, an analysis of the ACCORD data indicates that the detrimental effect of intensive therapy was not due to hypoglycemia or any specific combination of drug therapies.
How low of a blood glucose goal should clinicians strive to achieve for their patients?
Clinicians need to tailor blood glucose treatment goals for each individual. In light of the ACCORD results, a patient with cardiovascular disease or multiple cardiovascular risk factors may not be suitable for intensive therapy to achieve near normal A1C values. To help lower a patient’s risk of developing diabetes-related cardiovascular disease, it is important for clinicians to also target other factors that increase CVD risk such as high blood pressure, high cholesterol, and smoking; or those that decrease it such as daily aspirin and physical activity.
What is ADA’s message to patients in light of the ACCORD trial announcement?
The American Diabetes Association strongly cautions people with diabetes to not be alarmed and overinterpret the findings from the ACCORD trial. ADA continues to reinforce that good control of blood glucose is important in the management of diabetes and its complications. Additional analysis of the ACCORD trial is underway, as are other studies which examine the question of what level of control is optimal for the treatment of diabetes.
The American Diabetes Association continues to advise most people with diabetes to strive for an A1C (a measure of long-term blood glucose control) of less than 7 percent. Recent data indicates that more than half of the population with diabetes in the U.S. has an A1C less than 7 percent and the improved glucose control appears to be of great benefit rather than harm.
People with diabetes are at increased risk for cardiovascular disease such as heart attack or stroke. Managing blood pressure and cholesterol can help lower the risk of having a heart attack or stroke. It is important to work with your health care team to determine which treatment targets and medicines are best for you. Patients should never alter their course of treatment without first consulting with their health care team.
Is there any way to prevent an adverse effect from happening?
The importance of glucose control in diabetes is firmly established. Evidence from the landmark Diabetes Control and Complications Trial (DCCT), the U.K. Prospective Diabetes Study (UKPDS), and other recent data shows that good glycemic control reduces the risk of complications and appears to be safe.
However, very low A1C goals are not for everyone with diabetes and the American Diabetes Association’s treatment guidelines state that treatment should be tailored to the individual patient. Of note, the American Diabetes Association (in its Standards of Medical Care) states: “Less stringent A1C goals may be appropriate for patients with a history of severe hypoglycemia, patients with limited life expectancies, children, individuals with comorbid conditions, and those with longstanding diabetes and minimal or stable microvascular complications.”
Is there an A1C level below 7 percent that predicts a serious side effect?
There is no A1C threshold below which there will be a serious side effect in most people with diabetes. Many people with diabetes have no adverse consequences even with A1C levels in the normal range (4-6%). Others, for example, who have long-standing diabetes and who take multiple medications, may experience hypoglycemia even at higher A1C levels. This is why treatment goals must be individualized.
Why is managing blood glucose so important in the management of diabetes?
Results from the landmark Diabetes Control and Complications Trial (DCCT) and United Kingdom Prospective Diabetes Study (UKPDS) established that management of blood glucose, as measured by A1C, reduces the risk for microvascular (small vessel) complications of diabetes such as blindness, kidney disease, and nerve damage. Some studies have suggested that higher A1C levels are also associated with higher risk of macrovascular (large vessel) complications such as heart attack and stroke.
For well over a decade, the American Diabetes Association has recommended specific A1C treatment goals. The Association currently recommends that most people with diabetes achieve an A1C less than 7 percent.
What is A1C?
A1C (pronounced, ‘a-one-see’) is a test that measures average blood glucose control over the past 2 to 3 months. The American Diabetes Association recommends that most people with diabetes strive for an A1C of less than 7 percent and have their A1C level checked at least twice a year.
What is the link between diabetes and heart disease?
The most life-threatening consequences of diabetes are heart disease and stroke, which strike people with diabetes more than twice as often as they do others. Most of the cardiovascular complications related to diabetes have to do with a condition called atherosclerosis, or hardening of the arteries. Diabetes can change the chemical makeup of some of the substances found in the blood and this can cause blood vessels to narrow or to clog up completely. Simply treating diabetes per se is not the cause of increased cardiovascular disease.
What does “good control” of blood glucose mean?
Good control means getting as close to a normal (nondiabetic) blood glucose level as you safely can. Ideally, this means levels between 70 and 130 mg/dl before meals, and less than 180 two hours after starting a meal, with an A1C of less than 7 percent.
You should set your goals with your health care team and treatment goals should be individualized to consider other comorbid health conditions, such as a person’s history of heart disease or stroke.
For more information on diabetes and cardiovascular disease, contact the American Diabetes Association at 1-800-DIABETES (1-800-342-2383) or www.diabetes.org
