One Year Real-World Use of the Control-IQ Advanced Hybrid Closed-Loop Technology

Diabetes Technol Ther. 2021 Sep;23(9):601-608. doi: 10.1089/dia.2021.0097. Epub 2021 Apr 21.


Background: The t:slim X2™ insulin pump with Control-IQ® technology from Tandem Diabetes Care is an advanced hybrid closed-loop system that was first commercialized in the United States in January 2020. Longitudinal glycemic outcomes associated with real-world use of this system have yet to be reported. Methods: A retrospective analysis of Control-IQ technology users who uploaded data to Tandem's t:connect® web application as of February 11, 2021 was performed. Users age ≥6 years, with >2 weeks of continuous glucose monitoring (CGM) data pre- and >12 months post-Control-IQ technology initiation were included in the analysis. Results: In total 9451 users met the inclusion criteria, 83% had type 1 diabetes, and the rest had type 2 or other forms of diabetes. The mean age was 42.6 ± 20.8 years, and 52% were female. Median percent time in automation was 94.2% [interquartile range, IQR: 90.1%-96.4%] for the entire 12-month duration of observation, with no significant changes over time. Of these users, 9010 (96.8%) had ≥75% of their CGM data available, that is, sufficient data for reliable computation of CGM-based glycemic outcomes. At baseline, median percent time in range (70-180 mg/dL) was 63.6 (IQR: 49.9%-75.6%) and increased to 73.6% (IQR: 64.4%-81.8%) for the 12 months of Control-IQ technology use with no significant changes over time. Median percent time <70 mg/dL remained consistent at ∼1% (IQR: 0.5%-1.9%). Conclusion: In this real-world use analysis, Control-IQ technology retained, and to some extent exceeded, the results obtained in randomized controlled trials, showing glycemic improvements in a broad age range of people with different types of diabetes.

Keywords: Automated insulin dosing; Closed-loop control; Continuous glucose monitoring; Time in range.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Blood Glucose
  • Blood Glucose Self-Monitoring* / methods
  • Child
  • Diabetes Mellitus, Type 1* / drug therapy
  • Female
  • Humans
  • Hypoglycemic Agents / therapeutic use
  • Insulin / therapeutic use
  • Insulin Infusion Systems
  • Male
  • Middle Aged
  • Retrospective Studies
  • Technology
  • Young Adult


  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin