COUNTERREGULATORY HORMONE RESPONSES AFTER LONG-TERM CONTINUOUS SUBCUTANEOUS INSULIN INFUSION WITH LISPRO INSULIN

OBJECTIVE - To determine whether the long-term use of insulin lispro ( LP) affects the counterregulatory hormone response to hypoglycemia. RE SEARCH DESIGN AND METHODS - Ten patients (age range 26-51 years; ratio of men to women 9:1; BMI 24.9 +/- 0.48; mean HbA(1c) 7.84 +/- 0.25%) with IDDM, treated with continuous subcutaneous insulin infusion (CSII ; Disetronic H-TRON V100) were studied using a double-blind, crossover design. Patients were randomized to LP or human regular insulin (HR) for 3 months and then crossed over to the other insulin for an additio nal 3 months. All meal boluses were given 0-5 min before breakfast, lu nch, and dinner. Counterregulatory hormone responses to a stepped hypo glycemic clamp (consecutive glucose levels in mmol/l: 4.2; 3.5; 2.8, e ach for 1 h) were evaluated at the end of each treatment period. RESUL TS - HbA(1c) was significantly lower with LP versus HR (7.47 +/- 0.28% vs. 7.9 +/- 0.26%, P = 0.04). The incidence of hypoglycemia per 30 da ys (capillary blood glucose <3.0 mmol/l and/or symptoms) during the la st month of the study was significantly lower with LP versus HR (8.7 /- 2.9 vs. 11.8 +/- 2.9, P = 0.03). The total daily insulin dosage was not different in the two treatment periods. There was no episode of s evere hypoglycemia or diabetic ketoacidosis. The peak growth hormone, cortisol, glucagon, and epinephrine responses during the same period o f hypoglycemia were not different for each treatment period. CONCLUSIO NS - The use of LP in CSII results in improved glycemic control and a decrease in the frequency of hypoglycemia without adversely affecting counterregulatory hormone response to hypoglycemia.