Combination of insulin and glibenclamide in the treatment of elderly non-insulin dependent (type 2) diabetic patients

Abstract

A double-blind crossover study was undertaken to determine whether glibenclamide could improve glycaemic control in patients not adequately controlled by insulin. Nine elderly outpatients with non-insulin dependent (type 2) diabetes participated in the study. In addition to their regular insulin treatment, the patients were given either glibenclamide 5 mg twice daily or placebo tablets for 2 months followed by the opposite combination for a further 2 months. The fasting plasma glucose concentrations were lower during the insulin plus glibenclamide period than during the insulin plus placebo period and the difference tended to increase at the end of each study period (p less than 0.01 and 0.001). The level of haemoglobin A, (HbA1) decreased significantly from 13.8 +/- 0.6% (mean +/- SE) to 12.4 +/- 0.6% during the insulin + glibenclamide period (p less than 0.01); in contrast, there was no change during the insulin + placebo period. The 24-hour urinary glucose excretion was reduced during the insulin + glibenclamide period compared with insulin + placebo (p less than 0.05). Basal and glucagon stimulated C-peptide concentrations did not significantly differ between the two treatment regimens. The results suggest that glibenclamide can improve the glycaemic control in insulin-treated elderly diabetics by mechanisms which still are to be elucidated.