Residual effects of a short-term intensified insulin therapy in type 2 diabetic patients with oral drug failure.

The present study was designed to evaluate the long-term effects of a short course of insulin therapy on glycaemic control in type 2 diabetic patients after failure with oral therapy. Twenty type 2 diabetic patients poorly controlled with maximal doses of sulfonylurea were given intensified insulin treatment for 12-14 days adjusted so as to achieve near normoglycaemia. They were then restarted on their previous oral medication to which one bedtime injection of NPH insulin was added if the mean diurnal glucose profile exceeded 10 mM (n = 8). At the follow up evaluation (n = 18), 6 +/- 1 months later, fasting glucose (12.3 +/- 1.1 to 8.3 +/- 0.6 mM) and HbA1c (10.2 +/- 0.5 to 8.5 +/- 0.5%) levels were significantly improved in the patients receiving a combined therapy. In the group maintained on sulfonylurea alone, fasting glucose (13.2 +/- 0.7 to 6.9 +/- 0.7 mM) and HbA1c (9.6 +/- 0.6 to 6.9 +/- 0.6%) were also significantly improved in 5 patients who had lost weight (-6 +/- 1 kg) whereas none of these parameters were significantly different from the preinsulin value in the 6 patients whose weight remained unchanged. In conclusion, the current results do not provide any evidence that short-term insulin therapy is able to reinduce the efficacy of a previously ineffective sulfonylurea treatment, on a long term basis.