TY - JOUR
T1 - Predictors of Time-in-Range (70-180 mg/dL) Achieved Using a Closed-Loop Control System
AU - Schoelwer, Melissa J.
AU - Kanapka, Lauren G.
AU - Wadwa, R. Paul
AU - Breton, Marc D.
AU - Ruedy, Katrina J.
AU - Ekhlaspour, Laya
AU - Forlenza, Gregory P.
AU - Cobry, Erin C.
AU - Messer, Laurel H.
AU - Cengiz, Eda
AU - Jost, Emily
AU - Carria, Lori
AU - Emory, Emma
AU - Hsu, Liana J.
AU - Weinzimer, Stuart A.
AU - Buckingham, Bruce A.
AU - Lal, Rayhan A.
AU - Oliveri, Mary Clancy
AU - Kollman, Craig C.
AU - Dokken, Betsy B.
AU - Cherñavvsky, Daniel R.
AU - Beck, Roy W.
AU - Deboer, Mark D.
N1 - Publisher Copyright:
© Copyright 2021, Mary Ann Liebert, Inc., publishers 2021.
PY - 2021/7/1
Y1 - 2021/7/1
N2 - Background: Studies of closed-loop control (CLC) in patients with type 1 diabetes (T1D) consistently demonstrate improvements in glycemic control as measured by increased time-in-range (TIR) 70-180 mg/dL. However, clinical predictors of TIR in users of CLC systems are needed. Materials and Methods: We analyzed data from 100 children aged 6-13 years with T1D using the Tandem Control-IQ CLC system during a randomized trial or subsequent extension phase. Continuous glucose monitor data were collected at baseline and during 12-16 weeks of CLC use. Participants were stratified into quartiles of TIR on CLC to compare clinical characteristics. Results: TIR for those in the first, second, third, and fourth quartiles was 54%, 65%, 71%, and 78%, respectively. Lower baseline TIR was associated with lower TIR on CLC (r = 0.69, P < 0.001). However, lower baseline TIR was also associated with greater improvement in TIR on CLC (r = -0.81, P < 0.001). During CLC, participants in the highest versus lowest TIR-quartile administered more user-initiated boluses daily (8.5 ± 2.8 vs. 5.8 ± 2.6, P < 0.001) and received fewer automated boluses (3.5 ± 1.0 vs. 6.0 ± 1.6, P < 0.001). Participants in the lowest (vs. the highest) TIR-quartile received more insulin per body weight (1.13 ± 0.27 vs. 0.87 ± 0.20 U/kg/d, P = 0.008). However, in a multivariate model adjusting for baseline TIR, user-initiated boluses and insulin-per-body-weight were no longer significant. Conclusions: Higher baseline TIR is the strongest predictor of TIR on CLC in children with T1D. However, lower baseline TIR is associated with the greatest improvement in TIR. As with open-loop systems, user engagement is important for optimal glycemic control.
AB - Background: Studies of closed-loop control (CLC) in patients with type 1 diabetes (T1D) consistently demonstrate improvements in glycemic control as measured by increased time-in-range (TIR) 70-180 mg/dL. However, clinical predictors of TIR in users of CLC systems are needed. Materials and Methods: We analyzed data from 100 children aged 6-13 years with T1D using the Tandem Control-IQ CLC system during a randomized trial or subsequent extension phase. Continuous glucose monitor data were collected at baseline and during 12-16 weeks of CLC use. Participants were stratified into quartiles of TIR on CLC to compare clinical characteristics. Results: TIR for those in the first, second, third, and fourth quartiles was 54%, 65%, 71%, and 78%, respectively. Lower baseline TIR was associated with lower TIR on CLC (r = 0.69, P < 0.001). However, lower baseline TIR was also associated with greater improvement in TIR on CLC (r = -0.81, P < 0.001). During CLC, participants in the highest versus lowest TIR-quartile administered more user-initiated boluses daily (8.5 ± 2.8 vs. 5.8 ± 2.6, P < 0.001) and received fewer automated boluses (3.5 ± 1.0 vs. 6.0 ± 1.6, P < 0.001). Participants in the lowest (vs. the highest) TIR-quartile received more insulin per body weight (1.13 ± 0.27 vs. 0.87 ± 0.20 U/kg/d, P = 0.008). However, in a multivariate model adjusting for baseline TIR, user-initiated boluses and insulin-per-body-weight were no longer significant. Conclusions: Higher baseline TIR is the strongest predictor of TIR on CLC in children with T1D. However, lower baseline TIR is associated with the greatest improvement in TIR. As with open-loop systems, user engagement is important for optimal glycemic control.
KW - Closed-loop systems
KW - Insulin pump
KW - Time-in-range
KW - Type 1 diabetes
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U2 - 10.1089/dia.2020.0646
DO - 10.1089/dia.2020.0646
M3 - Article
C2 - 33689454
AN - SCOPUS:85109166400
SN - 1520-9156
VL - 23
SP - 475
EP - 481
JO - Diabetes Technology and Therapeutics
JF - Diabetes Technology and Therapeutics
IS - 7
ER -