A new study highlights the importance of good long-term control of blood sugar in people with diabetes.

The study found that poor long-term blood sugar control in diabetics is associated with a substantial increase in the risk of dying from ischemic heart disease — the type of heart disease characterized by restricted blood flow to the arteries of the heart.

However, with reasonably good blood sugar or "glycemic" control, the risk of death from ischemic heart disease is comparable to that seen in people without diabetes, the researchers found.

"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, told Reuters Health. "In addition, it is necessary to control other cardiovascular risk factors properly."

In a 20-year follow up study, Dale and colleagues compared death rates from ischemic heart disease in 205 patients newly diagnosed with diabetes and 205 matched subjects without diabetes at the outset.

The researchers report in the European Heart Journal that diabetic patients had nearly a two-fold greater risk of dying compared to nondiabetic patients.

The risk for death from ischemic heart disease was four times higher in diabetic subjects with poor long-term blood sugar control compared to the control group, whereas in diabetes patients with "reasonably good" blood sugar control the risk was almost the same as in subjects without diabetes, Dale said.

These findings, 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."