The study by Mayo Clinic researchers is the first, large population-based study of a group of common medications used to lower blood sugar. The drugs are called sulfonylureas and second-generation sulfonylureas -- known as SU2s -- include glimepiride (Amaryl), glipizide (Glucotrol, Glucotrol XL) and glyburide (DiaBeta, Micronase, Glynase).

Many patients with diabetes are at increased risk for heart failure and that's raised concern among some physicians that SU2s might impair the heart’s ability to withstand stress, thus reducing patients’ ability to survive heart attacks.

But the Mayo Clinic study, led by Dr. Veronique Roger, found no evidence to support that fear.

"These data do not support the concern among some physicians of an adverse impact of SU2 on survival after a heart attack," Roger said. "These results provide clinical guidance for physicians faced with managing a growing number of diabetic patients."

The research was presented Monday in Orlando, Fla., during the American Heart Association’s Scientific Sessions 2007.