MORE UNIFORM DIURNAL BLOOD-GLUCOSE CONTROL AND A REDUCTION IN DAILY INSULIN DOSAGE ON ADDITION OF GLIBENCLAMIDE TO INSULIN IN TYPE-1 DIABETES-MELLITUS - ROLE OF ENHANCED INSULIN SENSITIVITY

Combination therapy with insulin and sulphonylurea has gained acceptan ce in management of subjects with Type 2 (non-insulin-dependent) diabe tes mellitus. However, its role in management of Type 1 (insulin-depen dent) diabetes mellitus remains controversial. In this study, the effe ct of combination therapy with insulin and glibenclamide on metabolic control, daily insulin dosage, and insulin sensitivity was assessed in subjects with Type 1 diabetes mellitus. Ten men with Type 1 diabetes mellitus participated in a randomized, double-blind, crossover, clinic al trial with three treatment regimens, namely (1) insulin alone, (2) insulin and placebo, (3) insulin and glibenclamide, each lasting 3 mon ths. Combination therapy induced: (1) reduction in daily insulin dosag e; (2) more uniform blood glucose control as reflected by a lower aver age 24 h blood glucose level, a smaller difference between mean prepra ndial and 2 h postprandial blood glucose concentrations, decreased 24 h urine glucose excretion, and a decline in number of hypoglycaemic ev ents; (3) improved insulin sensitivity as expressed by more rapid plas ma glucose disappearance rate, without a significant alteration in fas ting plasma glucagon and Ih postprandial serum C-peptide levels; when compared with treatment with either insulin alone or with insulin and placebo. Therefore, it is apparent that the addition of glibenclamide to insulin reduces daily insulin dosage and renders a greater uniformi ty to diurnal blood glucose control, most probably secondary to enhanc ement of insulin sensitivity.