Patients with type 1 diabetes who received an insulin pump had similar improvements in glycemic control as patients who simply received education about giving themselves multiple daily injections (MDIs), according to a randomized trial. After two years, HbA1c levels had decreased in both groups, with no significant difference between them. The groups also had similar rates of moderate or severe hypoglycemia.
The study was published by The BMJ on March 30 and summarized in the April ACP Diabetes Monthly. The following commentary by Lorraine L. Lipscombe, MD, MSc, was published in the ACP Journal Club section of the Aug. 15 Annals of Internal Medicine.
The past decade has seen major advances in type 1 diabetes management, with associated improvements in prognosis. Continuous subcutaneous insulin infusion pumps are one such advance. Advantages of these pumps over MDIs include more precise insulin delivery, automated bolus calculators, and ability to adjust basal insulin rates throughout the day. Disadvantages include higher cost and greater risk for metabolic decompensation with malfunction. Some evidence suggests that insulin pumps improve glucose control and outcomes compared with MDIs. However, these benefits may also be attributed to the enhanced diabetes care and self-management retraining that is given during the transition to insulin pumps.
The REPOSE trial showed that, when all patients on MDIs received structured education, there was no additional benefit of switching to insulin-pump therapy for glycemic control, hypoglycemia rates, or quality of life. Effective self-management training may then be more important than the method of insulin administration in patients with type 1 diabetes.
Some caveats should be considered. First, REPOSE only included patients without a clear indication or preference for pump treatment, who may have been less likely to use all of the pump features designed to optimize glycemic control. Therefore, these results cannot be applied to highly motivated patients who request pump treatment. Second, the risks for hypoglycemia and diabetic ketoacidosis (DKA) with insulin pumps will be greatly reduced with such newer technologies as closed-loop systems that integrate continuous glucose monitoring with insulin administration. In the meantime, without clear added benefits of insulin pumps and their higher cost, complexity, and risk for DKA, we should focus on enhancing education rather than changing to pump treatment in patients with type 1 diabetes who are inadequately controlled on MDIs.