Off-Label advanced Hybrid Closed-Loop vs Non-Algorithmic Approach in pregnant women with T1D

Background: Automated insulin delivery is advocated as the standard of care for patients with type 1 diabetes mellitus (T1D). However, the glycaemic targets of most closed-loop (aHCL) systems are typically higher than desirable for pregnancy. Following the AiDAPT trial, the only HCL system (CamAPS FX) is approved in Europe for use in pregnancies complicated by T1D and has demonstrated safety and efficacy in improving maternal glycaemic control. Aim: This single-centre observational study aims to evaluate glycaemic control and maternal-fetal outcomes in pregnant women with T1D using off-label aHCL systems compared with those on non-aHCL insulin pump and multiple daily insulin (MDI). Methods: A retrospective analysis of metabolic data and neonatal outcomes was performed in 55 pregnant women with T1D (16.4% on off-label aHCL, 38.2% on non-aHCL, 45.4% on MDI). Results: Patients on non-aHCL started pregnancy with higher first trimester HbA1c levels (6.9±0.8% vs 6.3±0.7% vs 6.5±1.4%), pregnancy-specific TIR (ps-TIR 63-140 mg/dL) not achieved (60±15% vs 71±12% vs 74±11%, p=0. 029) with the higher TBR (12±11% vs 5±4% vs 7±6%, p=0.09) and worse CV than in the other groups (36.6±5% vs 32.4±4% vs 33.7±4%). While patients with MDI and aHCL reached ps-TIR levels early in pregnancy, ps-TIR was not reached in non-aHCL even in the third trimester (67.8±11% vs 76.1±10% vs 70.5±14%). A higher incidence of large for gestational age (LGA) was observed in non-aHCL insulin pump users compared to aHCL and MDI users (47.4% vs 22.2% vs 10%, p=0.03). Conclusions: In our retrospective real-world analysis, aHCL and MDI users achieved similar glycaemic control in terms of ps-TIR and HbA1c, while non-aHCL users didn’t achieve the desired target. We observed a higher number of LGA in non-aHCL users, which is consistent with the literature. The off-label aHCL system was safe with a lower TBR and CV.