Insulin Requirements for Basal and Auto-Correction Insulin Delivery in Advanced Hybrid Closed-Loop System: 4193 Days’ Real-World Data of Children in Two Different Age Groups

Abstract

Background: The insulin requirements of people with type 1 diabetes (T1D) can vary throughout the day due to factors such as biorhythm, exercise, and food intake. The MiniMed 780G system delivers micro boluses to adjust basal insulin and delivers auto-correction boluses to meet insulin needs when micro bolus increases are insufficient. Through analysis of MiniMed 780G data, this study investigates the variations in insulin requirements throughout the day. Methods: 4193 days’ pump and continuous glucose monitoring (CGM) data of 34 children using MiniMed 780G were collected from Medtronic CareLink. Micro and auto-correction boluses were analyzed on an hourly basis for two age groups: below nine years old and above nine years old. Glycemic metrics were analyzed based on International CGM consensus. Results: The mean age was 12.3 years and mean duration of diabetes was 6.1 years. The mean time in range (TIR) and glucose management indicator (GMI) were 80.5% and 6.6%, respectively. The micro bolus (basal) ratio between 05.00 and 07.00 was significantly higher than the ratio between 10.00 and 03.00 ( P < .01), whereas micro bolus was significantly lower between 19.00 and 21.00 than those between 00.00 and 10.00 ( P < .001). The auto-correction ratio between 21.00 and 00.00 was significantly higher than those between 03.00-17.00 ( P < .001) and 19.00-21.00 ( P = .008), whereas auto-correction was significantly lower between 07.00 and 10.00 than those between 10.00 and 03.00 ( P < .001). The micro bolus ratio was significantly higher in children below nine years old than in children above nine years old between 21.00-00.00 ( P = .026) and 00.00-03.00 ( P = .003). Conclusion: The basal insulin need follows a diurnal pattern with two significantly different periods—high between 00.00 and 10.00 and low between 10.00 and 00.00. The auto-correction rates are low between 05.00 and 10.00 and show an increasing pattern peaking between 21.00 and 00.00. These findings are compatible with the dawn and reverse dawn phenomena.

Safety, Metabolic and Psychological Outcomes of Medtronic MiniMed 780G™ in Children, Adolescents and Young Adults: A Systematic Review

“…This AID system improves TIR compared to baseline by at least 10% after 4 weeks without any increase in TBR [ 15 , 29 , 38 ], and this finding has also been reported by other studies with longer follow-up periods of up to 1 year [ 30 , 31 , 34 , 36 , 39 ], which demonstrated a more remarkable improvement in TIR of up to 22% [ 35 , 37 ] without any significant change in BMI z -score [ 39 ]. Basically, the MiniMed™ 780G system allows a TIR of 75–80% to be reached [ 32 , 33 ]. It is worth noting that in all these studies, people with diabetes used rapid-acting insulin.…”

“…Another retrospective study evaluating the raw data for 4193 patient-days of 34 children using the AHCL system reported the following results for glucose control indicators: HbA1c 7.1 ± 0.9%, TIR 80.5 ± 7.8%, TAR1 14.5 ± 6.2%, TAR2 2.5 ± 2.2%, TBR1 2 ± 1.5%, TBR2 0.5 ± 0.8%, CV 33.1%, mean SG 136.7 ± 11.6 mg/dL, SD of mean glucose 45.5 mg/dL, and GMI 6.6%. No differences in the main CGM metrics were found between children older and younger than 9 years of age [ 33 ].…”

Pediatric Type 1 Diabetes: Is Age at Onset a Determining Factor in Advanced Hybrid Closed-Loop Insulin Therapy?

“…Overall, the development of type 1 diabetes before the age of 10 years results in a loss of 17.70 years of life (95%CI 14.50-20.40) for women and 14.20 years of life (12.10-18.20) for men [1,4]. These data may justify an increased focus on cardioprotection in people with early-onset T1D [5][6][7].…”

Impact on glucometric variables and quality of life of the advanced hybrid closed‐loop system in pediatric and adolescent type 1 diabetes

“…Multiple studies have shown that closed‐loop systems enable better glycemic control measured in glycated hemoglobin (HbA1c), TIR, hyperglycemia, hypoglycemia, lower variability, and improved quality of life 3–8 …”

“…1,2 Multiple studies have shown that closed-loop systems enable better glycemic control measured in glycated hemoglobin (HbA1c), TIR, hyperglycemia, hypoglycemia, lower variability, and improved quality of life. [3][4][5][6][7][8] One of the closed-loop systems is the Medtronic MiniMed 780G device. It features an advanced hybrid closed-loop (AHCL) algorithm that includes automatic delivery of basal insulin every 5 min, adjustable targets of 100 (5.50), 110 (6.10), and 120 (6.70) mg/dL (mmol/L), and automatic delivery of correction boluses every 5 min.…”