Aim: To compare glycaemic metrics at 3 and 6 months in patients with type 1 diabetes on a 670G hybrid closed-loop (HCL) system after using a sensor-augmented pump (SAP) for at least 3 months.
Materials and methods: A retrospective study from a centre that has the largest number of 670G users in the United States was conducted. Data from 202 SAP users were reviewed. Sixty-one patients were excluded (two for steroid use, four for pregnancy, 27 for previous Enlite use, and 28 for non-continuous use of 670G). Out of 141 patients who met the inclusion criteria, 127 (aged 21-68 years) had complete data.
Results: HbA1c levels decreased by 0.4% at 3 months and were maintained at 6 months (7.6 ± 0.07 vs. 7.2 ± 0.08, P < 0.001) with no weight gain at 6 months. Time-in-range (70-180 mg/dL) increased from 59.5% ± 1.1% to 70.2% ± 1.2% and 70.1% ± 1.1% at 3 and 6 months (P < 0.001), respectively. At 6 months, time spent in hypoglycaemia (<70 mg/dL) and time spent in hyperglycaemia (>180 mg/dL) were reduced by 30% (2.2% ± 0.2% vs. 3.2% ± 0.2%; P < 0.05) and 26% (28.3% ± 1.2% vs. 38.1% ± 1.2%; P < 0.001), respectively. More time in auto-mode was associated with improved continuous glucose monitoring metrics, lower HbA1c and decreased glycaemic variability. Time in auto-mode declined in men after 3 months, while women maintained similar auto-mode use throughout the study.
Conclusions: The HCL system improved HbA1c levels and time-in-range, and decreased time spent in hypoglycaemia and hyperglycaemia at 6 months. Auto-mode use was significantly correlated with continuous glucose monitoring metrics and glycaemic outcomes.
Keywords: CSII; continuous glucose monitoring; glycaemic control; insulin pump therapy; type 1 diabetes.
© 2019 John Wiley & Sons Ltd.