OBJECTIVE: To compare parameters of glycemic control among three types of hybrid closed loop (HCL) systems in children with T1D (CwD) using population-wide data from the national pediatric diabetes registry ČENDA. METHODS: CwD aged <19 years treated with Medtronic MiniMed 780G (780G), Tandem t:slim X2 (Control-IQ) or do-it-yourself AndroidAPS (AAPS) systems for >12 months and monitored by CGM >70% of the time were included. HbA1c, times in glycemic ranges, and Glycemia Risk Index (GRI) were used for cross-sectional comparison between the HCL systems. RESULTS: Data from 512 CwD were analyzed. 780G, Control-IQ and AAPS were used by 217 (42.4%), 211 (41.2%), and 84 (16.4%) CwD, respectively. The lowest HbA1c value was observed in the AAPS group (44 mmol/mol; IQR 8.0, p<0.0001 vs any other group), followed by Control-IQ and 780G groups (48 (IQR 11) and 52 (IQR 10) mmol/mol, respectively). All of the systems met the recommended criteria for time in range (78% in AAPS, 76% in 780G, and 75% in Control-IQ users). CwD using AAPS spent significantly more time in hypoglycemia (5% vs 2% in 780G and 3% in Control-IQ) and scored the highest GRI (32, IQR 17). The lowest GRI (27, IQR 15) was seen in 780G users. CONCLUSION: Although all HCL systems proved effective in maintaining recommended long-term glycemic control, we observed differences that illustrate strengths and weaknesses of particular systems. Our findings could help in individualizing the choice of HCL systems.

• Keywords
• AndroidAPS, hybrid closed loop, pediatrics, registry, type 1 diabetes,
• MeSH
• Diabetes Mellitus, Type 1 * drug therapy   MeSH
• Child MeSH
• Glycated Hemoglobin MeSH
• Hypoglycemia * chemically induced   epidemiology   MeSH
• Insulin therapeutic use   MeSH
• Insulin Infusion Systems MeSH
• Blood Glucose MeSH
• Humans MeSH
• Cross-Sectional Studies MeSH
• Registries MeSH
• Blood Glucose Self-Monitoring MeSH
• Check Tag
• Child MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Glycated Hemoglobin MeSH
• Insulin MeSH
• Blood Glucose MeSH