Time in Tight Range in AHCL Systems: Propensity-Score-Matched Analysis of MiniMed 780G and Control-IQ

Background: Advanced hybrid closed-loop (AHCL) systems have improved the glycemic control in type 1 diabetes (T1D). While time in range (TIR) (70–180 mg/dL) is the standard metric, time in tight range (TITR) (70–140 mg/dL) offers a stricter assessment. Real-world comparisons using the TITR are limited. This study compared the TIR and TITR metrics between the MiniMed™ 780G and Tandem Control-IQ™ in adults with T1D. Methods: This retrospective, single-center study included 42 propensity-score-matched adults with T1D (28 MM780G users and 14 Tandem Control-IQ users), each with ≥3 months of AHCL system use. Glycemic metrics from continuous glucose monitoring (CGM) were analyzed over a 14-day period. Comparisons between groups were conducted using Mann–Whitney U tests, adjusted linear regression, and linear mixed-effects models accounting for repeated measures. Results: At three months, the MM780G users achieved significantly higher TITR (60.1% ± 12 vs. 49.5% ± 9.3; p = 0.005) and TIR (83.7% ± 7.6 vs. 72.1% ± 7.5; p < 0.001) values, along with lower glucose variability, compared to these values in the Tandem Control-IQ users. The linear regression model confirmed that the MM780G was independently associated with a higher TITR (β = 14.2; p = 0.005). Mixed-effects modeling for the TIR showed a significant interaction between timepoint and device type (β = 4.81; p = 0.006), favoring the MM780G. Conclusions: In this real-world analysis, both AHCL systems improved glycemic control, but the MiniMed 780G could be associated with a superior performance in achieving tighter glucose targets without increasing hypoglycemia. TITR may serve as a valuable complementary metric alongside TIR in evaluating AHCL systems’ effectiveness. However, these findings should be interpreted cautiously due to limitations such as the retrospective design, small sample size, potential residual confounding, and lack of standardization in the device settings. Further studies are warranted to confirm these results and assess their generalizability.