RESUMO
OBJECTIVE: To evaluate the use of U500 regular insulin therapy in insulin-resistant patients with type 2 diabetes mellitus who were previously treated with high-dosage U100 insulin regimens. METHODS: At a large Veterans Affairs medical center, a retrospective chart review was performed of all patients whose U100 insulin regimens were converted to U500 regular insulin regimens using a protocol to ensure patient safety. Patients were followed up for longer than 6 months. Data reviewed included total daily dosage of insulin before and after regimen conversion and changes in hemoglobin A1c, body weight, lipids, and episodes of severe hypoglycemia. RESULTS: Fifty-three patients met inclusion criteria. Average hemoglobin A1c level on U100 insulin regimens was 9.1 ± 1.7%, which decreased to 8.1 ± 1.3% (P<.001) after an average of 20 months (range, 6-52 months) on U500 insulin. The total daily insulin dosage at study end was not significantly greater on U500 (415 ± 166 units/day) than on U100 insulin (391 ± 120 units/day) (P = .34). Body weight did not change significantly (134 ± 29 kg vs 136 ± 30 kg, P = .18). There was a 20-mg/dL decrease in total cholesterol (P = .014). Triglyceride values decreased by 97 mg/dL (P = .005). Eight episodes of severe hypoglycemia were documented in patients treated with U500 insulin, but this was similar to the incidence in these same patients while treated with U100 insulin. CONCLUSION: We conclude that U500 insulin can be safely and effectively used in insulin-resistant patients with type 2 diabetes followed up at a large Veterans Affairs medical center using a protocol that ensures patients are thoroughly educated and carefully monitored.
