Distribution of Hypo- and Hyperglycemic Event Duration in Type 1 Diabetes Using Automated Insulin Delivery

Aim: To evaluate the distribution and duration of hypo- and hyperglycemic events in type 1 diabetes using automated insulin delivery (AID). Methods: Continuous glucose monitoring data over 60 days were obtained from 83 users of the Tandem Control IQ (CIQ) insulin pump and 65 users of the MiniMed 780G (MM) system, all with active sensor time >70%. The frequency and duration of consensus-defined hypoglycemic (<70 mg/dL) and hyperglycemic (>180 mg/dL) events were calculated. Hypoglycemic event duration was analyzed in 5-minute increments from 15 to 120 minutes, and hyperglycemic event duration in 15-minute increments from 15 to 430 minutes. Results: The median number of hypoglycemic events per 60 days was 28 (interquartile range [IQR] 11-45) for CIQ and 23 (IQR 13-40) for MM ( P = .31). The median duration of hypoglycemic events was 30 (IQR 20-45) minutes with CIQ and 35 (IQR 25-50) minutes with MM, corresponding to a 15% longer duration with MM than with CIQ (MM/CIQ ratio 1.15, 95% confidence interval [CI], 0.10-0.23, P < .001). The median duration of hyperglycemic events was 90 (IQR 45-180) minutes with CIQ and 85 (IQR 45-165) minutes with MM, with no statistically significant difference between systems (MM/CIQ ratio of 0.95 [95% CI, 0.86-1.05], P = .33) Conclusion: Analysis of the duration and distribution of hypo- and hyperglycemic events complements standard time-in-range metrics. In this study, 1 AID system was associated with a longer duration of hypoglycemic events despite similar overall exposure to hypoglycemia.