Overweight and obese adults (body mass index of 25 or over) between the ages of 40 and 70 should be screened for abnormal blood glucose (sugar) levels and type 2 diabetes as part of a heart disease risk evaluation, according to new guidelines from the U.S. Preventive Services Task Force (USPSTF). The new guidelines are the first update on diabetes screening for the general public by the USPSTF since 2008. At that time, the task force recommended diabetes screening only for adults with high blood pressure.
Individuals whose test results indicate high blood glucose levels or type 2 diabetes should be referred for intensive diet and exercise counseling, according to the new guidelines. The task force's new recommendations are based on six studies its members reviewed that suggested that increasing exercising and tailoring diets could help prevent type 2 diabetes.
"Losing weight reduces the chances of developing diabetes, which is why our recommendation focuses on diet and exercise," said William Phillips, M.D., M.P.H., a professor of family medicine at the University of Washington and a task force member.
According to the task force, the rate of type 2 diabetes, the most common form of diabetes in the U.S., has increased in the last 15 years. Diabetes occurs when the body can't process and use all the glucose from certain foods, especially carbohydrates. People with type 2 diabetes will frequently have high levels of glucose in their blood, but they may not have any symptoms, which is why screening is important. Left untreated, diabetes can lead to very serious conditions, including heart disease and stroke, blindness, kidney disease, and limb amputations.
In 2012, the last year for which data on diabetes were available to the panel, 12% of American adults had diabetes and 37% had abnormal blood glucose levels that put them at increased risk for developing diabetes and the complications of diabetes, including heart disease. That translates into about 29.1 million Americans having diabetes in 2012, but about 8.1 million of those did not know they had the disease. And close to 90 million adults had high blood glucose levels that, left untreated, could progress to type 2 diabetes.
"Diabetes is a leading cause of heart attacks and strokes," said Michael Pignone, M.D., M.P.H. chief of the division of general internal medicine at the University of North Carolina-Chapel Hill and a member of the task force. "The good news is, we can identify people at risk and help them make lifestyle changes that may ultimately prevent or delay complications associated with this serious illness."
The USPSTF's screening guidelines for diabetes differ from the current ones released by the American Diabetes Association (ADA), which recommends routine screening in adults 45 years or older. The ADA also advises earlier screening in people with more than one risk factor for type 2 diabetes, such as a family history of the disease and being overweight.
The task force recommends screening for diabetes using one of several tests: hemoglobin A1c, fasting blood glucose, or oral glucose tolerance test. If the initial result of one of these tests is abnormal, the same test is repeated on another day. If the repeat result is also abnormal, a diagnosis of diabetes is made.
When deciding to get screened for diabetes, the task force advises people to talk to their healthcare practitioner, who can help determine whether screening is right for them. USPSTF guidelines are often adopted by most healthcare practitioners, and it is more likely that insurance companies will cover the cost for people who are recommended by the new guidelines to get diabetes screening.