SAT100 Management Of Post-exercise Hyperglycemia In A Patient Using Control IQ Artificial Pancreas System - A Case Report

Disclosure: P. Sharma: None. A. Ramirez Berlioz: None. Introduction: The automated insulin delivery (AID) Tandem Control IQ (CIQ) system has improved glycemic control with increased time in range (∼10%) & decreased hypoglycemic events (∼1%) through automatic basal rate modifications & correction bolus administration. The sleep & exercise activity (EA) decrease hypoglycemia risk. The CIQ EA decreases basal rate for predicted glucose =<140 mg/dl, increases basal rate for predicted glucose >160 mg/dl, and suspends insulin delivery for glucose =<80 mg/dl. It is designed for mild-moderate physical activity and is aggressive for high-intensity aerobic exercise or endurance training. High-intensity activity can cause post-exercise hyperglycemia. There is minimal data regarding management of post-exercise hyperglycemia when using AID systems. Case Report: A 40 year old female with uncomplicated type 1 diabetes mellitus managed by Tandem CIQ system reported post-exercise hyperglycemia after starting a new exercise routine. Previous routine included cardio and weight training on 4 days of the week. She had recently started a stationary cycling routine lasting 15-45 minutes with varying intensity. She would start the CIQ EA 1.5 hours prior to exercise and stop after completion. The pump report revealed hyperglycemia between 200-300 mg/dl occurring within 1 hour after exercise, lasting several hours after. Patient attempted using normal mode during exercise, manual bolusing immediately after exercise, and post-exercise insulin sensitivity factor modification without effect. Stopping EA 10-15 mins before completion led to elimination of post-exercise hyperglycemia. Discussion: The CIQ EA is designed to decrease exercise-induced hypoglycemia. After high-intensity exercise, the CIQ algorithm can exaggerate the hyperglycemia. High-intensity routines such as sprints, weight-lifting, intensive cycling, are associated with varying degrees of hyperglycemia. Our patient's new cycling routine was higher-intensity compared to what she previously did, leading to persistent hyperglycemia. Some recommendations to avoid post-exercise hyperglycemia in patients on AID systems include using CIQ normal mode during exercise, utilization of a temporary basal rate, or administration of a manual correction bolus. However, the use of normal mode or temporary basal rates can lead to glycemic variations during exercise. A manual correction bolus administered after exercise may be too late to avoid the hyperglycemia and leads to subsequent hypoglycemia due to enhanced insulin sensitivity post-activity. We tried stopping EA a few minutes before routine completion and found that 10 minutes was appropriate. We suggest that discontinuation of the EA 10 minutes before completion of exercise routine can alleviate post-exercise hyperglycemia. Additional studies are required to confirm whether this method would work on a larger scale. Presentation: Saturday, June 17, 2023