COMMENTARY Update: Pediatric Diabetes Swathi Sethuram | Robert Rapaport Division of Pediatric Endocrinology & Diabetes, Icahn School of Medicine at Mount Sinai, New York, New York Correspondence Swathi Sethuram, Division of Pediatric Endocrinology & Diabetes, Icahn School of Medicine at Mount Sinai, 1 Gustave L. Levy Place, Box 1616, New York, NY 10029. Email: swathi.sethuram@mountsinai.org KEYWORDS: closed loop, continuous glucose monitor, genetics and T1D, insulin pump, mortality and T1D, type 1 diabetes mellitus 1 | INTRODUCTION In view of the constantly developing field of type 1 diabe- tes mellitus (T1D), we bring to you this review of three recent articles that highlight etiology, technology, and implications related to T1D. We highlight these publica- tions because of their pertinence to pediatric and adult populations with T1D, hence affecting clinical practice as well as providing direction for future research. 1.1 | New closed-loop device for type 1 diabetes Technology has revolutionized the management of T1D. The use of continuous glucose monitors (CGM) reduces the frequency of hypoglycemia. 1 However, multiple daily injections and insulin pumps are the only means of insu- lin administration at present. The only Food and Drug Administration approved “artificial pancreas” or closed- loop insulin pump is the Medtronic's MiniMed 670G pump, which is a hybrid system that is able to automati- cally adjust basal insulin but requires manual input of blood glucose and carbohydrate intake with meals. In the October 2019 issue of the New England Jour- nal of Medicine, data from the 6-month International Diabetes Closed Loop (iDCL) trial of a new closed-loop system for T1D were published. 2 This study, conducted in 7 United States university hospitals as a parallel, unblinded study for 26 weeks compared the safety and efficacy of the Control IQ t:slim X2 closed-loop insulin pump to a sensor-augmented open-loop insulin pump (without low glucose suspension feature). This closed- loop system provides automated basal and bolus insu- lin delivery. Patients aged between 14 and 71 years of age with a diagnosis of T1D and on insulin (pump or multiple daily injections) for at least 1 year were included in the trial. They were randomized in a 2:1 ratio to use the closed- loop system (112 participants) vs a continuous glucose monitor (Dexcom G6) augmented pump (58 participants) without a cutoff for hemoglobin A1C (HbA1C, 5.4 to 10.6% in both groups). Patients had a 2-8 week run in period followed by visits at 2, 6, 13, and 26 weeks and multiple telephone encounters in between, maintaining 100% retention at the end of the trial. The primary out- come of this trial was the percentage of time spent in glu- cose target range (70-180 mg/dL) as measured by the Dexcom G6. Glucose levels in the target range increased from 61 ± 17% at baseline to 71 ± 12% during the 6 months in the closed-loop group whereas it remained at 59 ± 14% in the control group (95% confidence interval [CI], 9 to 14; P < 0.001). This meant that those in the closed-loop group spent 2.4 hours more time per day within target range and this finding was sustained throughout the study. The greatest difference in the median percentage of time in the target range was at 5 AM (89% in the closed- loop group vs 62% in the control group). As a secondary outcome, it was found that the closed-loop group spent a significantly lesser percentage of time in hypoglycemia <70 mg/dL (1.58 ± 1.15) compared to the control group (2.25 ± 1.46) (P < 0.001). They also spent a significantly lesser percentage of time with glucose <54 mg/dL com- pared to the control group (0.29 ± 0.29 vs 0.35 ± 0.32, P = 0.02). The mean difference in HbA1C at 26 weeks DOI: 10.1111/1753-0407.13033 © 2020 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd Journal of Diabetes. 2020;1–3. wileyonlinelibrary.com/journal/jdb 1