University of Cambridge researchers are reporting that people with type 2 diabetes who maintain strict control of their blood sugar-defined as lowering their A1c levels by 0.9% over a five-year period-can lower their risk of non-fatal heart attacks by 17 percent.
Their conclusions, published in the May 23 issue of the British medical journal The Lancet, are at odds with the results of ACCORD, a U.S. study in strict blood sugar control that was suspended last year when researchers noticed a statistically significant increase in the number of type 2s experiencing heart attacks while practicing strict control.
The ACCORD study tracked 10,251 type 2s. Some doctors, after learning about the apparent increase risk of heart attacks brought on by strict control, concluded that an A1c of less than 7% can increase the risk of cardiovascular problems.
But the British study, which tracked almost three times as many type 2 patients as ACCORD-33,040-concluded otherwise, saying that A1c levels below 7% decreased, not increased, the chances of heart attacks among diabetic patients.
Strict blood sugar control is achieved by adding medications to the mix taken by diabetes patients or by increasing the doses of the medicines they are already taking.
In the British study, patients under strict control had an average A1c of 6.6%, versus 7.5% among patients who were not receiving extra medications or higher doses.
While the study provides welcome news that the lowering of blood sugar levels decreases the risk of heart attacks, researchers say that a lowered A1c cannot by itself eliminate the increased risk of heart attack that all type 2s face. High blood pressure and high levels of “bad” cholesterol are also two major contributors to their high susceptibility to cardiovascular problems.