While automated insulin delivery (AID) systems are now commercially available, over 40 percent of people with type 1 diabetes manage their insulin with multiple daily injection therapy (MDI). AID systems can improve time-in-range in adults, however it is not clear if optimal MDI therapy can achieve the same glycemic targets. We have previously shown that a K-nearest-neighbors decision support system (KNN-DSS) for MDI can deliver safe recommendations and achieves high agreement with endocrinologists. Here, we report glycemic outcomes as we compare KNN-DSS with two artificial pancreas systems: fading-memory-proportional-derivative (FMPD), and model-predictive control (MPC).

We utilized a platform accepted by U.S. Food and Drug Administration for the evaluation of artificial pancreas technologies, the UVA-Padova simulator. In silico, 100 adults with varying insulin sensitivities, weight, and insulin dosing behaviors underwent a 3-arm study comparing KNN-DSS, FMPD, and MPC algorithms. Each UVA-Padova subject received a unique study meal pattern that was repeated across study arms. The two primary outcome measures were % time-in-range and % time-in-hypoglycemia. Secondary outcome measures included LGBI and HGBI risk index.

The KNN-DSS was able to achieve 79.6 ± 15.4 %time-in-range after 12 weeks compared with 83.6 ± 8.3% for the MPC and 84.2 ± 9.24% for the FMPD. The KNN-DSS achieved comparable time below 70 mg/dL (0.79%, [0 1.6]) with the MPC-AP (0.62%, [0 1.8]) and FMPD (0%, [0 0.72]). The KNN-DSS also achieved comparable LGBI (2.55) with the MPC-AP (2.68). This simulation assumes perfect adherence to insulin dosing regimens, and while % time-in-range may be higher than expected, the results indicate that decision support in MDI may yield comparable glycemic outcomes with automated insulin delivery systems if people are compliant. Results of this study will be used to guide the design of an upcoming human clinical trial.


N.S. Tyler: None. W. Hilts: None. C.M. Mosquera-Lopez: None. L.M. Wilson: None. R. Dodier: None. J. El Youssef: None. J.R. Castle: Advisory Panel; Self; Novo Nordisk Inc. Consultant; Self; ADOCIA, Dexcom, Inc., Zealand Pharma A/S. Other Relationship; Self; Pacific Diabetes Technologies, Roche Diabetes Care. P.G. Jacobs: Consultant; Self; SFC Fluidics. Research Support; Self; Dexcom, Inc. Stock/Shareholder; Self; Pacific Diabetes Technologies. Other Relationship; Self; AgaMatrix.


The Leona M. and Harry B. Helmsley Charitable Trust (2018PG-T1D001)

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