Athletes with T1D using CSII routinely remove their pump for prolonged periods, predisposing to hyperglycemia and ketosis. We examined the safety and efficacy of an “Untethered” approach - evenly splitting basal insulin between adjusted CSII and a daily injection of insulin degludec. This randomized cross-over study explored glycemic outcomes following in-clinic, fasted exercise (90-minute moderate- and 30-minute high-intensity). After a 1-week run-in, subjects were randomized to Usual CSII or Untethered CSII, for 5-week periods including a week of optimization, and then crossed over. Nineteen patients (age 34 ± 10 (mean ± SD), T1D duration 16 ± 11 years; mean A1C 7.1 ± 0.5) have completed both periods. In the 6 hours following moderate exercise, the Untethered arm showed improved mean glucose and spent 61% more time in range relative to the Usual arm (p<0.001) (Table). Similar trend was seen following high intensity exercise. There were no differences in pre-exercise glucose or total daily insulin dose (TDD). Both regimens were well-tolerated with no serious adverse events. An “Untethered” regimen of injected basal insulin and adjusted-rate CSII is safe and effective in avidly exercising subjects with T1D using CSII and may offer improved glycemic control in the immediate period following moderate-intensity exercise.


R. Aronson: Research Support; Self; AstraZeneca, Becton, Dickinson and Company, Boehringer Ingelheim Pharmaceuticals, Inc., Eli Lilly and Company, Janssen Pharmaceuticals, Inc., Medtronic, Merck & Co., Inc., Novo Nordisk Inc., Sanofi, Senseonics. A. Li: None. R.E. Brown: None. S. McGaugh: None. L. Yavelberg: None. M. Riddell: Advisory Panel; Self; Xeris Pharmaceuticals, Inc. Research Support; Self; Dexcom, Inc. Speaker's Bureau; Self; Insulet Corporation, Medtronic MiniMed, Inc. Stock/Shareholder; Self; Zucara Therapeutics Inc.


Novo Nordisk

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