Efficacy and Safety of Real-Life Usage of MiniMed 670G Automode in Children with Type 1 Diabetes Less than 7 Years Old

Abstract

The Medtronic MiniMed 670G system with SmartGuard™ (Medtronic, Northridge, CA) is a commercial hybrid closed-loop (HCL) system approved for use in 2018 for children >7 years. Studies of this HCL system in subjects >7 years old show improvement in glycemic control, but no study has described its use in younger children. This is a retrospective analysis of patients with type 1 diabetes (T1D) <7 years of age who used the 670G HCL system at Seattle Children's Hospital for 3 months. We compared 2-week data from Carelink™ while in manual mode (MM) with suspend before low active with those in auto mode (AM). We used two tailed t-test to compare variables related to glycemic control. Sixteen children were reviewed [age of AM start: average 4.3 years (range 2-6); 10 male]. The average time in AM was 6.3 ± 2.9 months (range 3-12). There was a statistically significant change for A1c [MM 7.9% (62.8 mmol/mol), AM 7.4% (57.4 mmol/mol); P-value <0.001], percentage time in range (MM 42.8%, AM 56.2%; P-value <0.001), percentage hypoglycemia (MM 1.3%, AM 2.4%; P-value 0.04), and average sensor glucose [MM 200 mg/dL (11.1 mmol/L), AM 176 mg/dL (9.8 mmol/L); P-value <0.001]. No serious adverse reports noted. This case series showed improvement in glycemic control in very young children using the 670G HCL. We did note more hypoglycemia although no serious adverse events, such as hypoglycemic seizure, were reported. A HCL system can be used in young children with T1D safely and effectively and should be an option for children <7 years.

Keywords: Closed loop; Hybrid closed loop; Medtronic 670G; Pediatric; Type 1 diabetes.