NEW YORK (Reuters Health) – New research shows that poor long-term glycemic control is associated with a substantial increase in the risk of death from ischemic heart disease (IHD) in patients with diabetes. However, with reasonably good glycemic control, the risk of death from IHD is comparable to that seen in people without diabetes.

“Due to these findings, good glycemic control in persons with newly diagnosed diabetes should be recommended,” Dr. Ane C. Dale from the Norwegian University of Science and Technology in Trondheim, Norway told Reuters Health. “In addition, it is necessary to control other cardiovascular risk factors properly.”

In a 20-year follow up study, Dr. Dale and colleagues compared mortality from IHD in 205 patients with newly diagnosed diabetes and 205 matched subjects without diabetes at baseline. Among the patients with diabetes, blood glucose control was assessed by annual measurements of HbA1c.

The researchers report in the European Heart Journal for June that the adjusted hazard ratio for death from IHD was 1.8 in the diabetic patients compared to the nondiabetic subjects.

“The risk for death from IHD was four times higher in diabetic subjects with HbA1c in the highest quartile (hazard ratio 4.2) compared to the control group,” Dr. Dale noted, “whereas in diabetes patients with reasonably good metabolic control the risk was almost the same as in subjects without diabetes.”

She added, “Analyzing HbA1c as a continuous time-varying variable showed 30% (HR 1.3) higher risk per increment of HbA1c among diabetes patients without known cardiovascular disease at baseline.”

These findings, Dr. Dale and colleagues conclude in their report, are “compatible with the hypothesis that good glucose control reduces the risk of coronary complications in patients with diabetes.”

Reference:
Eur Heart J 2009;30:1372-1377.