Mei Nakatsuji

Background: Although several studies have evaluated the impact of prolonged infusion set use in insulin pump users on glycemic management with the use of continuous glucose monitoring (CGM), real-world assessments without intervention have been unavailable. Methods: This retrospective observational study recruited individuals with type 1 diabetes who received insulin pump therapy with real-time CGM. Insulin pump and CGM logs were extracted from the Medtronic CareLink system, and a dataset was constructed programmatically, counting tracking days from infusion set replacement every 24 hours up to day 4. The primary outcome was mean sensor glucose (SG) level, and the impact of infusion set usage duration on glycemic management was assessed. Results: The study enrolled 45 individuals with a median age of 40 (interquartile range = 32-51) years and median body mass index of 22.5 (21.2-23.8) kg/m². Mean SG was significantly higher on day 4 (median of 151.9 [136.5-173.7] mg/dL) than on day 2 (144.4 [124.0-162.9] mg/dL, P = .024). Similarly, time above range (TAR), time in range (TIR), and time in tight range (TITR) had worsened on day 4 compared with day 2. The TAR increased from a median of 22.0% (7.3%-35.8%) on day 2 to 27.6% (17.7%-44.9%) on day 4, whereas TIR decreased from 74.2% (59.9%-87.1%) to 66.5% (52.0%-79.8%) and TITR decreased from 47.6% (37.1%-67.5%) to 42.2% (34.6%-54.1%). Conclusions: Our evaluation of the real-world impact of prolonged infusion set use revealed an association between longer use and worsening of glycemic management.