278-OR: Impact of a Parameter Change in DBLG1 System

In DBLG1 System, multiple parameters can be customized. This study aims at analyzing the impact of a change of the normoglycemia aggressiveness (NA), the hyperglycemia aggressiveness (HA) and the glucose target (GT) on the glycemic control of T1D patients. Data is collected from 5977 adult patients who gave their consent (3/2021 to 11/2022). Periods of 14 days before and after a single parameter change are collected. Conditions of 70% of data availability and of 75% of time spent in closed loop are requested for each period. The time in range 70-180 mg/dL (TIR), the time below range 70 mg/dL (TBR), the mean sensor glucose (MG), the coefficient of variation (CV) and the mean daily insulin dose (MDI) of the two periods are compared for each parameter using a Wilcoxon Signed-Rank test. Control for the multiple tests is done using the Benjamini-Hochberg procedure. The size effect is inferred using Cohen’s d. The results are summarized in the table below. On average, an increase of HA or NA improves the TIR and reduces the MG. The TBR appears to increase when the HA is increased and to decrease when HA or NA are reduced. A decrease of the GT increases TIR, TBR and CV, and decreases MG, conversely an increase of the GT decreases TIR, TBR and CV, and increases MG. The size effect is small. The impact on MDI is small or not significant. The most impactful parameter seems to be the GT which affects the MG proportionally. HA and NA had a lower than expected impact. Disclosure A.Adenis: Employee; Diabeloop SA. A.Vesin: Employee; Diabeloop SA. H.M.Romero-ugalde: Employee; Diabeloop SA. M.Louis: Employee; Diabeloop SA. C.V.Huber: Employee; Diabeloop SA. L.Pou: None. Y.Tourki: Employee; Diabeloop SA. E.Huneker: Employee; Diabeloop SA. P.Y.Benhamou: Advisory Panel; Eli Lilly and Company, Insulet Corporation, Novo Nordisk, Consultant; Dexcom, Inc., Employee; Diabeloop SA.