A retrospective observational study evaluating the safety and effectiveness of commercially available automated insulin delivery systems in people with type 1 diabetes and gastroparesis

Abstract Aims A retrospective observational cohort study evaluating real‐world outcomes in adults with type 1 diabetes and gastroparesis using automated hybrid closed loop insulin delivery systems (HCL). Materials and Methods All adults with type 1 diabetes and gastroparesis attending King's College Hospital diabetes service and using continuous glucose monitoring (CGM) from 5 October 2023 to 16 January 2025 were included. Glycaemic data (HbA 1c , CGM metrics), hypoglycaemia awareness (Gold score), diabetes distress (DDS2), and acute complications (DKA, severe hypoglycaemia) were collected from electronic health records and glucose platforms for 12 months pre‐ and post‐HCL initiation. Results From 1827 clinic attendees, 36 adults with gastroparesis were identified, with 17 initiating HCL. HCL and non‐HCL groups had comparable baseline characteristics and metrics (HCL: Mean(SD) HbA 1c 70(21)mmol/mol [8.6(1.9)%]; Time in range (TIR) 36.8 (21.9) % vs. non‐HCL: HbA 1c 71 (25) mmol/mol [8.6(2.3)%]; TIR 37.1(19.2)%, p = 0.73). Post‐HCL, HbA 1c median(IQR) fell to 57(52.5–65.0) mmol/mol [7.4(7.0–8.1)%] ( p < 0.001). TIR increased to 55.7(19.9)% ( p < 0.001), with a significant reduction in Time above range Level 2 (TAR2) [>13.9 mmol/L/>250 mg/dL](32.7% to 14.5%, p = 0.014). Gold score improved (2.5 to 1.5, p = 0.019), but DDS2 remained unchanged. No increase in DKA or severe hypoglycaemia occurred. Conclusions Within a specialist multidisciplinary team setting, HCL systems significantly reduce HbA 1c without increasing risk of severe hypoglycaemia or DKA in people with type 1 diabetes and gastroparesis.