Extended insulin boluses cannot control postprandial glycemia as well as a standard bolus in children and adults using insulin pump therapy

Introduction Insulin pumps are able to deliver bolus insulin as a standard, extended or combination bolus. There is minimal research to determine which bolus is preferable in different settings. Anecdotally, many patients utilizes only the standard bolus (SB) due to uncertainty regarding when and how to program the different bolus types. We compared postprandial glycemia when five different extended boluses (EBs) and an SB were used following a test meal. We sought to determine the impact of varying rates of insulin delivery from an EB on early postprandial glycemia. Methods We conducted a randomized, repeated measures trial of 20 children and adults comparing postprandial glycemic excursions following EBs given at five different rates with SB as a control. All EBs were delivered over 2 h. Rates of EBs were chosen to reflect EBs used in clinical practice: EB1HR=100% of insulin:carbohydrate ratio (ICR) per hour (200% ICR total dose); EB2HR=50% of ICR per hour; EB3HR=33% of ICR per hour; EB4HR=25% of ICR per hour; EB6HR=16% ICR per hour. A standardized breakfast was given and activity was standardized. Continuous glucose monitoring was used to assess glycemia for 2 h after the meal. Results The mean postprandial glycemic excursions were lower at 30, 60, and 90 min (p