Improvement of HbA1c and blood glucose stability in IDDM patients treated with lispro insulin analog in external pumps

OBJECTIVE To compare the efficacy of the short-acting insulin analog lispro (LP) with that of regular insulin in IDDM patients treated with an external pump. RESEARCH DESIGN AND METHODS Thirty-nine IDDM patients (age, 39.4 ± 1.5 years; sex ratio, 22M/17W; BMI, 24.4 ± 0.4 kg/m2; diabetes duration, 22.5 ± 1.6 years) who were treated by external pump for 5.1 ± 0.5 years were involved in an open-label, randomized, crossover multicenter study comparing two periods of 3 months of continuous subcutaneous insulin infusion with LP or with Actrapid HM, U-100 (ACT). Boluses were given 0–5 min (LP) or 20–30 min (ACT) before meals. Blood glucose (BG) was monitored before and after the three meals every day. RESULTS The decrease in HbA1c was more pronounced with LP than with ACT (−0.62 ± 0.13 vs. −0.09 ± 0.15%, P = 0.01). BG levels were lower with LP (7.93 ± 0.15 vs. 8.61 ± 0.18 mmol/l, P < 0.0001), particularly postprandial BG levels (8.26 ± 0.19 vs. 9.90 ± 0.20 mmol/l, P < 0.0001). Standard deviations of all the BG values (3.44 ± 0.10 vs. 3.80 ± 0.10 mmol/l, P = 0.0001) and of postprandial BG values (3.58 ± 0.10 vs. 3.84 ± 0.10 mmol/l. P < 0.02) were lower with LP. The rate of hypoglycemic events defined by BG < 3.0 mmol/l did not significantly differ between LP and ACT (7.03 ± 0.94 vs. 7.94 ± 0.88 per month, respectively), but the rate of occurrences of very low BG, defined as BG < 2.0 mmol/l, were significantly reduced with LP (0.05 ± 0.05 vs. 0.47 ± 0.19 per month, P < 0.05). At the end of the study, all but two (95%) of the patients chose LP for the extension phase. CONCLUSIONS When used in external pumps, LP provides better glycemic control and stability than regular insulin and does not increase the frequency of hypoglycemic episodes.