Sustained Follow-up of Automated Insulin Delivery in a Real-World Setting: Results at 2 Years of the French...

Automated insulin delivery (AID) systems improve glycemic control in people with type 1 diabetes (PwT1D), but evidence on effectiveness and safety in routine clinical practice over 2 years remains limited.

The Observatoire de la Boucle Fermée en France is a nationwide prospective observational study evaluating AID use in children and adults with type 1 diabetes in real-world conditions. The primary end point was time in range (TIR, 70-180 mg/dL). The primary analysis assessed the noninferiority of TIR at 24 months (M24) compared with 12 months (M12). Secondary analyses evaluated the superiority of glycemic outcomes at M24 versus baseline (M0), including HbA1c, continuous glucose monitoring metrics, and safety outcomes. A sensitivity analysis using a linear mixed-effects model examined the change in TIR between M0 and M24 according to baseline HbA1c (<8% vs. ≥8%), adjusted for age, sex, and diabetes duration.

Among 2741 PwT1D who initiated AID therapy, 2225 (81.1%) had available data at M24. Median TIR at M24 was noninferior to M12 (70.0% [62.0-77.0] at both time points). Compared with baseline, TIR increased by 12.0% at M24 (P < 0.0001), and HbA1c decreased from 7.6% to 7.1% (P < 0.0001). AID discontinuation at M24 occurred in 2.1% of participants. The proportions of participants experiencing at least one episode of severe hypoglycemia over the preceding 12 months were lower at M24 than at baseline. A significant interaction between time of AID use and baseline HbA1c category was observed (P < 0.001). At M24, TIR remained higher in participants with baseline HbA1c <8% compared with those with baseline HbA1c ≥8% (P < 0.0001).

In a large nationwide real-world cohort, AID use was associated with noninferior TIR between 12 and 24 months, significant improvements in glycemic outcomes compared with baseline, low rates of treatment discontinuation, and favorable safety outcomes.