Objective: To determine the safety and efficacy of U-500 regular insulin in pump therapy and to assess satisfaction with U-500 insulin pump therapy in patients with type 2 diabetes and severe insulin resistance.
Methods: We performed a retrospective review of medical records of 6 patients with type 2 diabetes and insulin resistance who had been using U-500 insulin pump therapy for at least 6 months. In addition, we conducted a telephone follow-up patient satisfaction survey.
Results: The mean age of the patients was 57 +/- 6 years. Of the 6 patients (3 men and 3 women), 4 were white, 1 was black, and 1 was Asian. The mean hemoglobin A1c value before continuous subcutaneous insulin infusion therapy with U-500 regular insulin was 9.1% +/- 1.8%, and the mean U-100 insulin dose required was 391 +/- 91 U/day. In comparison, the mean U-500 insulin dose required at 6 months was 59.2 +/- 13.6 U/day, which is equivalent to 296 +/- 68 U/day of U-100 insulin (P = 0.04), and the mean hemoglobin A1c value at 6 months after treatment with the insulin pump using U-500 regular insulin was 6.9% +/- 0.9% (P = 0.03). In addition, our study patients lost a mean of 6.1 lb during the 6-month period, and no patient had clinically significant episodes of hypoglycemia. The majority of the patients reported a higher satisfaction with the U-500 insulin pump therapy in comparison with conventional insulin treatment.
Conclusion: U-500 insulin pump therapy is a novel alternative for patients with type 2 diabetes and severe insulin resistance who have not met glycemic control goals with use of standard intensive insulin regimens.