In a randomized trial by Bergenstal et al., sensor-augmented pump therapy was compared with a regimen of multiple daily insulin injections in adults and children with inadequately controlled type 1 diabetes. Pump therapy was associated with a significant improvement in glycated hemoglobin levels, as compared with injection therapy.
Among adults, the use of an insulin pump has been shown to reduce glycated hemoglobin levels without an increased risk of hypoglycemia, as compared with a regimen of multiple daily insulin injections, but results in children have been inconsistent. Recent studies have suggested that patients who used sensor-augmented pump therapy with adherence to continuous glucose monitoring had improved glycated hemoglobin levels without an increased rate of hypoglycemia.
• What was the comparative efficacy of sensor-augmented insulin-pump therapy as compared to injectable insulin at 1 year?
At 1 year, the baseline mean glycated hemoglobin level (8.3% in the two study groups) had decreased to 7.5% in the pump-therapy group (absolute reduction, 0.8+/-0.8 percentage points), as compared with 8.1% in the injection-therapy group (absolute reduction, 0.2+/-0.9 percentage points), for a between-group difference in the pump-therapy group of -0.6 percentage points (95% confidence interval, -0.7 to 0.4; P<0.001).
• Was there any difference in the incidence of hypoglycemia or weight gain between the pump-therapy group and the injection-therapy group?
Rates of severe hypoglycemia and diabetic ketoacidosis were similar in the two study groups and in the two age groups. Among adults, weight increased by 2.4 kg in the pump-therapy group and by 1.8 kg in the injection-therapy group (P=0.19).
Morning Report Questions
Q: Did the frequency of sensor use correlate with the improvement in glycated hemoglobin?
A: In this study, a frequency of sensor use of 41 to 60% was associated with a reduction of 0.64 percentage points in glycated hemoglobin levels, and increasing sensor use to more than 80% doubled the effect.
Q: How was sensor-augmented insulin-pump therapy used in this study?
A: The pump-therapy group used a device that integrates an insulin pump with continuous glucose monitoring. The patients received training in intensive diabetes management, including carbohydrate counting and the administration of correction doses of insulin. Patients were first placed on insulin-pump therapy for 2 weeks, and then glucose sensors were introduced. Patients also completed online insulin-pump training and attended additional visits for insulin-pump and sensor training.
Figure 1. Glycated Hemoglobin Levels at 3, 6, 9, and 12 Months in All Patients and in Subgroups According to Age.