[Short-term intensive insulin therapy as a method of overcoming secondary failure of sulfonylureas in patients with type 2 diabetes (non-insulin-dependent)].

UNLABELLED

The study group comprised 56 patients (25 males and 31 females) with type 2 diabetes in whom the secondary failure to sulphonylurea derivates (SU) had developed. All patients were submitted for 14 days to therapy with 5 injections of insulin per day in total dose of insulin permitting to decrease the mean daily glycaemia below 8.8 mmol/l (160 mg/dl). After the termination of the intensive insulin therapy (IIT) the patients with insulin requirement below 44 U daily were alternatively qualified to treatment with SU (glybenclamide) alone or with this SU plus biguanide derivate (BG: phenformin), and those who needed more than 44 U daily continued conventional therapy with insulin alone or with insulin plus SU (glybenclamide). There was a marked reduction of fasting and postprandial blood glucose during the IIT and over the subsequent 15 months of the follow-up. The mean glycaemia which initially was in fasting state 12.5 +/- 2.4 mmol/l (225 +/- 43 mg/dl) and 2 hours after breakfast 18.1 +/- 2.8 mmol/l (325 +/- 50 mg/dl) decreased significantly and was in four groups between 8.0 +/- 0.3 mmol/l (144 +/- 5 mg/dl) and 10.8 +/- 0.5 mmol/l (194 +/- 9 mg/dl) in fasting state and between 10.5 +/- 0.3 (189 +/- 5 mg/dl) and 11.2 +/- 0.4 mmol/l (201 +/- 7 mg/dl) after breakfast. The least hypoglycaemic effect was found in patients who after IIT were treated exclusively with insulin (mean daily dose 53 +/- 2 IU) while the decrease of glycaemia was most evident in patients treated with SU given as a single drug or in combination with BG or with insulin (mean daily dose 19 +/- 1 IU). In all studied patients basal and stimulated (1 mg glucagon i.v.) C-peptide secretion markedly decreased during IIT, and greatly increased after its termination, and this increase persisted over following 15 months of observation, correlating with the initial values.

CONCLUSIONS

The short-term IIT in patients with NIDDM and secondary failure to SU is effective in reducing hyperglycaemia, and in most of them makes possible to continue the oral antidiabetic treatment with SU. The secretion of endogenous insulin seems to have only limited influence on the metabolic control of the patients treated with four different pharmacological regiments after IIT.