SHORT-TERM INTENSIVE INSULIN THERAPY IN INSULIN-REQUIRING DIABETES - EFFECTIVENESS AND FACTORS PREDICTING SUCCESS

Insulin-requiring diabetes (IRD) is a condition of permanent blood glu cose imbalance which occurs despite a regulated diet and treatment wit h maximum doses of oral anti-diabetic drugs (glibenclamide 15 mg/d + m etformin 1,700 mg/d). This report describes the results of a 2-year pr ospective study in 75 IRD patients treated to eliminate their insulin requirement. All had residual endogenous insulin secretion (REIS) (uri nary C peptide > 80 mu g/24 h and/or basal C peptide > 2.4 ng/ml) and were treated for 10 days by subcutaneous insulin infusion via a portab le pump. REIS was measured, and insulin resistance was determined by a n insulin tolerance test (ITT) to define their insulin sensitivity ind ex (DG/G) before and after 10-day intensive therapy. The patients were monitored as outpatients, and the attempt at remission was considered to be a failure (F) or a success (S). Thirty of the 75 patients (40 % ) were in remission at 1 year, and 14/67 (21 %) at 2 years. No clinica l criterion differentiated successes from failures at 1 year, nor was the initial degree of blood glucose imbalance or the REIS predictive o f the metabolic changes that occurred after insulin therapy. However, the drop in the insulin requirement (IR) (- 26 % for F and -39 % for S , p < 0.05) and the increases in the DG/G index (+ 68 +/- 51 % for F a nd 176 +/- 50 % for S, p < 0.01) after insulin therapy were indicative of their condition 1 year later. Receiving operating characteristic c urves showed that a 35 % decrease in IR and an 80 % increase in DG/G w ere indicative of a successful outcome at 1 year, with a specificity a nd sensitivity of about 70 %. It is concluded that a decrease in daily IR and an increase in the DG/G index during insulin treatment are pro gnostic indicators of the course of insulin-requiring diabetics after temporary intensive insulin treatment.