DOI: 10.2337/db23-111-lb ISSN: 0012-1797

111-LB: Smart Insulin Pen Correction Doses Delivered within Three Hours of a Previous Insulin Dose Improve Glycemia

  • Endocrinology, Diabetes and Metabolism
  • Internal Medicine

Background: An important feature of the InPen™ Smart Insulin Pen (SIP) is its ability to track active insulin, enabling opportunities to safely calculate correction doses any time after a bolus. This study investigated the frequency of users delivering correction doses and its impact on glycemia when delivered within 3 hours of a previous dose in both adult and pediatric InPen users with T1D or T2D.

Methods: A retrospective cohort analysis was performed using deidentified sensor glucose (SG) data from N=857 individuals with sufficient SG data (at least 70% of SG data each day), ≥3 boluses per day, and ≥1 correction dose per day on average in the 60-to-90th day period after starting InPen-use Jan 2022-Dec 2022. Each user's proportion of corrections delivered within 3 hours of a previous dose (notated PC3) was calculated, and users were split into two groups based on the median of PC3. Glycemic outcomes including percentage TIR, 70-180 mg/dL), TBR, <70 mg/dL and TAR, >180 mg/dL and average SG were determined from the latest 14 days of device use. Comparisons between groups were conducted using t-tests (Mann Whitney U test when data were non-normal) at ≤0.05. Duration of insulin action (DIA) distributions were also described.

Results: The median PC3 of the overall group was 32.5% (range 0-100%). The upper half of the group (≥32.5%) showed significantly higher TIR (57.8% vs 50.5%, p<0.0001), lower TAR (40.2% vs 47.8%, p<0.0001), and lower SG (175.7 mg/dL vs 190.8 mg/dL, p<0.0001), compared with the lower half (<32.5%). There was no significant change in TBR (1.9% vs 1.8%, p=0.77). Of the 857 users, 55.2% had DIA >3 hours (3.6±0.84; range 2-8). The average DIA of the upper half and the lower half were 3.4±0.8 hours and 3.8±0.8 hours, respectively (NS).

Conclusion: InPen™ SIP users who delivered at least 1 correction dose a day within 3 hours of a previous dose achieved overall higher TIR without an increase in TBR, when compared to those who administered correction insulin >3 hours after their previous dose.


G. Im: Employee; Medtronic. M. Smith: Employee; Medtronic. J. Macleod: Employee; Medtronic. R. A. Vigersky: Employee; Medtronic.

More from our Archive