Benefits and risks with glyburide and glipizide in elderly NIDDM patients

To compare the efficacy, benefits, and risks of glyburide and glipizide in elderly patients with non-insulin-dependent diabetes mellitus (NIDDM).

Twenty-one elderly outpatients (mean age 70 yr) were treated for 8 wk, after being dose-titrated to achieve a fasting plasma glucose (FPG) concentration of less than 7.8 mM with glyburide or glipizide in a randomized crossover trial. FPG and postprandial plasma glucose, serum C-peptide, and HbA1c levels were measured. In 13 patients, self-monitoring of blood glucose (SMBG) with a memory meter was performed seven times per week.

Glipizide (11.9 mg) and glyburide (8.4 mg) produced similar fasting and postprandial plasma glucose and HbA1c concentrations. No significant differences in basal or stimulated C-peptide levels were detected. Despite a few patient reports of hypoglycemia, a high incidence of SMBG readings less than 4.5 mM was attributed to the use of both drugs.

Both treatments proved effective for glycemic control; however, both second-generation sulfonylureas are associated with a significant risk of hypoglycemia in elderly NIDDM patients. The proper use of sulfonylureas in this population should include close surveillance of ambulatory glucose monitoring and intensive and repeated patient education about the risks of hypoglycemia.