Exercise and hypoglycemia complicate glucose management in type 1 diabetes mellitus (T1DM), and their relationship with glycemic variability remains incompletely defined. In an analysis published in Diabetology, continuous glucose monitoring (CGM) trajectories were evaluated to characterize glycemic patterns surrounding hypoglycemia in individuals using AID and non-AID therapies.

The study analyzed data from the Type 1 Diabetes and Exercise Initiative (T1DEXI). The cohort included 498 participants with T1DM, of whom 222 used AID and 276 used non-AID therapy. CGM data were evaluated from 48 hours before to 48 hours after hypoglycemic events. Metrics included GV indices and TBR. Analyses also examined the influence of hypoglycemia severity, episode duration, exercise, and sex.

GV increased before and after hypoglycemia in both AID and non-AID users, with statistically significant differences across multiple GV metrics. TBR elevation persisted across all groups and peaked around hypoglycemic episodes. Females using AID demonstrated significantly greater post-event glucose stability compared with females using non-AID therapy, representing a larger within-group difference than observed in males.

Individual-level analyses showed that hypoglycemia episodes lasting longer than 40 minutes were associated with prolonged TBR elevation. This pattern suggested a slower recovery period despite AID use. Similar trends were observed across hypoglycemia severity ranges of 41–50 mg/dL, 51-60 mg/dL, and 61-70 mg/dL.

These findings indicate that GV patterns evolve over extended periods around hypoglycemia and differ by insulin delivery method, episode duration, and sex. Extended GV monitoring may help identify hypoglycemia risk and inform future AID optimization strategies.