Aim: To evaluate the long-term efficacy, up to 2 years, of an advanced hybrid closed-loop (AHCL) system and to assess predictors of best results of the
therapy. Methods: We retrospectively evaluated 296 adults with
type 1 diabetes mellitus [mean age 42.8 ± 16.5 years, men 42.9%, duration of diabetes 22.5 ± 12.8 years, body mass index 24.9 ± 4.7 kg/m2, baseline
glycated hemoglobin (HbA1c) 63.4 ± 12.2 mmol/mol (8.0 ± 1.1%) ] who used the MiniMed™ 780G system. Demographic and clinical data were recorded. Continuous
glucose monitoring (CGM)-derived metrics and
insulin requirement were analyzed from the 4 weeks before and from every quarter after the switch to the AHCL system. Results: In the first quarter of AHCL treatment, all CGM metrics improved. Time in range (TIR) increased from 58.1 ± 17.5% to 70.3 ± 9.5% (P < 0.0001). The improvement lasted for up to 2 years of observation regardless of previous
insulin therapies. Throughout the period of observation, 53.4% of participants achieved mean TIR >70%, 92.6% mean time below range <4%, and 46% mean
glucose management
indicator <53 mmol/mol (7.0%). At univariable logistic regression older age, lower baseline HbA1c and
insulin requirement were associated with mean TIR >70%. At multivariable analysis, lower HbA1c remained independently associated with a better
glycemic control. However, mean TIR increased more in participants with a higher baseline HbA1c. Conclusions: Switching to an AHCL leads to a rapid improvement in
glycemic control lasting for up to 24 months along with a low risk for
hypoglycemia, confirming the safety of the system. Lower baseline HbA1c was the main predictor of better efficacy of
therapy, although higher baseline HbA1c was associated with the greatest improvement in mean TIR.