Six-Month Effectiveness of Advanced vs. Standard Hybrid Closed-Loop System in Children and Adolescents With Type 1 Diabetes Mellitus

Abstract

IntroductionThe purpose of this study was to assess the effectiveness of advanced- (a-HCL) vs. standard-hybrid closed-loop (s-HCL) systems use up to 6 months of treatment in a real-world setting of children and adolescents with T1DM.MethodsWe retrospectively evaluated all T1DM pediatric users of MiniMed™ 670G system (s-HCL) and 780G system (a-HCL). HbA1c and BMI were collected at baseline and three and six months after HCL start. Data on glycemic control were extracted from reports generated with CareLink™ Personal Software in Manual Mode, at HCL start, after one, three, and six months after HCL beginning.ResultsThe study included 44 individuals with a median age of 13.3 years (range 2- 21 years), 20 on s-HCL, and 24 on a-HCL. a-HCL users had a significantly lower HbA1c compared to s-HCL after six months of HCL use (7.1 vs. 7.7%). Significant differences in HbA1c between a-HCL and s-HCL users were found in children aged 7-14 years (7.1 vs. 7.7% after six months) and in those with a worse (HbA1c >8%) glycemic control at the beginning (7.1 vs. 8.1% after six months). No significant changes in HbA1c were found in a-HCL users that previously used a s-HCL system. Nevertheless, only the use of a-HCL significantly predicted a lower HbA1c after six months. All sensor-specific measures of glycemic control improved from Manual to Auto mode, in both s-HCL and a-HCL, without increasing time spent in hypoglycemia. However, the percentage of individuals with TIR>70% increased significantly in a-HCL users, who attained this target earlier and more stably: younger age, a higher rate of auto-correction, and a lower amount of CHO inserted predicted a TIR>70%. BMI SDS did not significantly change throughout the study period.ConclusionThis real-world study suggests that effectiveness might be greater in a-HCL than in s-HCL, with significant changes in HbA1c, and reaching earlier and more stably the target of TIR >70%, without increasing hypoglycemia or BMI. At the same time, previous users of s-HCL systems did not show any further improvement with a-HCL. Children under the age of 14 years of age, not represented in previous studies, seem to benefit the most from a-HCL pumps as well as individuals with the worst glycemic control.

Body mass index, basal insulin and glycemic control in children with type 1 diabetes treated with the advanced hybrid closed loop system remain stable - 1-year prospective, observational, two-center study

“…Noteworthy, our patients were characterized by more optimal glycemic control (lower GMI 6.48% vs 7.1% and higher TIR 81.16% vs 72%) after 6 months of AHCL use with a similar time spent in auto-mode (96.62% vs 96) and percent of sensor use (94.04% vs 92%) (36). Among the growing number of studies evaluating the AHCL Minimed 780G system these are to our knowledge the only two investigating the associations with BMI z-score (34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45). Former studies that observed BMI in children with T1D using insulin pumps other than AHCL showed not unequivocal results although the latest metaanalysis suggested no change in body mass (28, 29).…”

“…Similar results, also for a pediatric cohort of individuals with T1D, were obtained by Tornese et al., who reported no change in BMI z-score after 6 months of insulin treatment using either the hybrid closed-loop (Minimed 670G) or AHCL (Minimed 780G) systems. Noteworthy, our patients were characterized by more optimal glycemic control (lower GMI 6.48% vs 7.1% and higher TIR 81.16% vs 72%) after 6 months of AHCL use with a similar time spent in auto-mode (96.62% vs 96) and percent of sensor use (94.04% vs 92%) ( 36 ). Among the growing number of studies evaluating the AHCL Minimed 780G system these are to our knowledge the only two investigating the associations with BMI z-score ( 34 – 45 ).…”

“…Another interesting observation from this study is the increased use of the AHCL auto mode and no change of time of sensor use after one year of observation. The high and unchanged sensor use that was found also in another study may result from the necessity to use it to operate the Minimed system in automatic mode ( 36 ). The increasing time in auto-mode is optimistic and would suggest that the patients are not only keen to use it as a novelty but with time learn to rely on it and use it more.…”

“…We describe stable BMI z-scores of children and adolescents with T1D using the AHCL system during a 1-year follow up which is the first such long observation (34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45). Similar results, also for a pediatric cohort of individuals with T1D, were obtained by Tornese et al, who reported no change in BMI zscore after 6 months of insulin treatment using either the hybrid closed-loop (Minimed 670G) or AHCL (Minimed 780G) systems.…”

Carbohydrate Tolerance Threshold for Unannounced Snacks in Children and Adolescents With Type 1 Diabetes Using an Advanced Hybrid Closed-Loop System

“…The advanced hybrid closed-loop system HCL (a-HCL) systems differ from the standard by providing autocorrection insulin boluses to help correct high sensor glucose readings ( 1 ) with better glycemic outcomes ( 2 , 3 ), especially overnight, when postprandial glucose excursions are absent ( 4 ); however, they still require user interaction with meal boluses, inserting the grams of carbohydrates (CHO) to be consumed to fully control postprandial glucose excursions ( 1 ).…”