Clinical Impact of Initiation of U-500 Insulin vs Continuation of U-100 Insulin in Subjects With Diabetes.

Abstract

Background\nThe prevalence of obesity and diabetes mellitus (DM) has each increased drastically according to the Centers for Disease Control and Prevention. Growth of severe insulinresistant DM is predicted. U-500 insulin is highly concentrated and can replace less concentrated formulations in patients that need high insulin dosages. The aim of this study was to compare clinical outcomes of U-500 and U-100 insulin regimens in veterans with obesity and insulin resistance.\n\n\nMethods\nA single-site retrospective chart analysis of adult subjects was conducted from July 2002 to June 2011. Data for repeated measures spanned a period from 3 months before the intervention (baseline) through 12 months afterward. The main outcome was the variation in hemoglobin A1c (HbA1c). Other outcomes included incidence of severe hypoglycemia, weight changes, cardiovascular events, and number of injections.\n\n\nResults\nA total of 142 subjects (68 taking U-500 and 74 taking U-100) were included. Baseline characteristics were similar between the groups, except for weight, which was higher among U-500 subjects. Mean HbA1c was reduced by 0.84% and 0.56% in U-500 and U-100, respectively (P = .003). Severe hypoglycemia occurred in 5 subjects in the U-500 group and 1 in the U-100 group (P = .08). No significant difference was noted in the number of cardiovascular events. The mean number of daily injections was 2 in the U-500 group, and 4 in the U-100 group (P < .001).\n\n\nConclusions\nU-500 insulin, when compared with U-100 insulin regimens, led to a statistically significant reduction in HbA1c and number of insulin injections. Additional research is necessary to assess the risk of severe hypoglycemia in U-500 users. Neither regimen was associated with increased cardiovascular risk.