Exploring Factors that Influence Post-Exercise Glycemia in Youth with Type 1 Diabetes in the Real World: The Type 1 Diabetes Exercise Initiative Pediatric Study (T1DEXIP)
Objective: To explore 24-hour post-exercise glycemia and hypoglycemia risk, data from the Type 1 Diabetes Exercise Initiative Pediatric (T1DEXIP) study were analyzed to examine factors that may influence glycemia. Research Design and Methods: Real-world observational study with participant self-reported physical activity, food intake, and insulin dosing (multiple daily injection users). Heart rate, continuous glucose data, and available pump data were collected. Results: 251 adolescents (age=14±2 years [mean±SD]; HbA1c=7.1±1.3% (54±14.2mmol/mol); 42% female) recorded 3,319 activities over ~10 days. Trends for lower mean glucose post-exercise were observed in those with shorter disease duration and lower hemoglobin HbA1c; no difference by insulin delivery modality was identified. Larger glucose drops during exercise were associated with lower post-exercise mean glucose levels, immediately after activity (P<0.001) and 12-<16 hours later (P=0.02). Hypoglycemia occurred on 14% of nights following exercise vs. 12% after sedentary days. On nights following exercise, more hypoglycemia occurred when average total activity was ≥60 min/day (17% vs. 8% of nights, P=0.01) and on days with longer individual exercise sessions. Higher nocturnal hypoglycemia rates were also observed in those with longer disease duration, lower HbA1c, conventional pump use and if time below range was >4% in the previous 24hrs. Conclusions: In this large real-world pediatric exercise study, nocturnal hypoglycemia was higher on nights when average activity duration was higher. Characterizing both participant and event-level factors that impact glucose in the post-exercise recovery period may support development of new guidelines, decision support-tools and refine insulin delivery algorithms to better support exercise in youth with diabetes.