No Heart Healthy Benefits for Diabetics from Aggressive Blood Sugar Reduction

For the nearly 21 million Americans who have type 2 diabetes, aggressive blood sugar control has long been thought to prevent heart attack and stroke. Given that cardiovascular disease is the leading cause of death for type 2 diabetics and more than 75 percent of all diabetics die from heart disease, dietary restrictions are necessary to preserve and prolong life. However, researchers are now finding that there is no additional protection against heart attacks or strokes through severe control of blood sugar. In fact, the only positive benefit among those who received this aggressive treatment was a 20 percent reduction in kidney problems.

The studies conducted on type 2 diabetics were published online by the New England Journal of Medicine and are scheduled for presentation at the scientific meeting of the American Diabetes Association. Together, the studies included over 21,000 patients with type 2 diabetes within the U.S., Europe, and Australia.

The American trial, called Accord, was halted in February when the number of deaths actually increased after aggressive diabetes treatment was administered. The Australian study, called Advance, confirmed earlier research showing that intensive blood sugar control can protect the kidneys, but does not prevent heart attack or stroke. Accord had a treatment designed to push blood sugar below 6 percent and the goal of Advance was 6.5 percent. Both studies had a standard treatment goal of about 7 percent The normal range for a healthy non-diabetic individual would be below 6 percent.

According to the researchers, 5 percent of patients given intensive drug treatment in Accord died of any cause during the 3.5 years before the trial was stopped, compared to 4 percent of patients given standard treatment and cardiovascular deaths were 2.6 among those who got more treatment versus 1.8 percent. This translated to 41 excess deaths among the heavily treated group.

In an accompanying commentary to the published studies, Harlan Krumholz of Yale University says, "The path we thought was clear for preventing these complications in diabetics has now been thrown into question."

In another commentary, William Cefalu of Louisiana State University suggested that doctors may want to increase their target blood sugar to 7 percent for high-high risk patients as this would reduce the risk of side effects from the drug combinations used in aggressive therapy.

In comparing the two diabetes trials, researchers stated that they are getting some insight into why patients in one trial were more likely to die after aggressive treatment while patients in the other trial were not. Weight gain, the use of multiple drug combinations and possibly getting blood sugar levels too low, too quickly may all have been factors in causing premature deaths. "These findings reinforce that blood glucose lowering in diabetes is safe and has an important role to play in the prevention of serious complications," said Dr. Anushka Patel of the University of Sydney, who presented findings from the study at the American Diabetes Association meeting in San Francisco.