A five-year study of 2,613 people treated for diabetes at Italian clinics shows that tight blood sugar control may not be the number-one priority for patients who have other medical problems.
The study, which was published in the December 15, 2009 issue of the Annals of Internal Medicine, was led by Dr. Sheldon Greenfield, a professor of medicine at the University of California at Irvine. Dr. Greenfield set out to determine how much of a reduction in cardiovascular problems was gained by patients with diabetes who achieved A1c levels of 6.5% or below. (The American Diabetic Association recommends 7% as the goal that most people with type 2 diabetes should aim for). He found that lower A1c’s worked best to reduce heart risks in people who had few medical problems besides their diabetes. But for people with other medical problems, such as high blood pressure, high cholesterol, and foot or gastrointestinal ailments, lower blood glucose levels did significantly lower their risk of cardiovascular events such as stroke or heart attack.
Greenfield and his associates concluded that people who have diabetes and other medical problems may want to focus more on the treatment of those other problems and not make tight blood sugar control their first priority. In a recent HealthDay article, Greenfield is quoted as saying an A1c level between 7% and 8% for type 2 patients who have significant other medical problems is a reasonable goal.
Dr. Greenfield’s study comes in the wake of other studies, such as the ACCORD study that was suspended in 2008, which showed that very tight blood glucose control actually increased the risks of cardiovascular events-the opposite of what researchers expected. In the ACCORD study, more than 10,000 Americans with type 2 diabetes were tracked to see the effects of tight blood glucose control on the risk of cardiovascular disease. In many cases, patients reached A1c’s as low as 6%. However, researchers began noting a statistically significant increase in the number of tight-control patients who experienced or died from cardiovascular problems, and they called off the study.
At the same time, a larger European-based international study very similar to ACCORD showed no statistically significant increase in cardiovascular risks among tightly controlled type 2s. So there is still an ambiguity about the benefits of tight control. Greenfield’s study shows that the presence of other medical problems may have been a factor in the ACCORD findings because the emphasis on tight control may have distracted attention from other medical problems.
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