Frequency of rebound hyperglycemia in adults with type 1 diabetes treated with different insulin delivery modalities

Background: For people with type 1 diabetes (T1D), ensuring fast and effective recovery from hypoglycemia while avoiding posthypoglycemic hyperglycemia (rebound hyperglycemia, RH) can be challenging. The objective of this study was to investigate the frequency of RH across different treatment modalities and its impact on glycemic control. Methods: This cross-sectional real-world study included adults with T1D using continuous glucose monitoring and attending the outpatient clinic at Steno Diabetes Center Copenhagen. RH was defined as ≥1 sensor glucose value (SG) >10.0 mmol/L (180 mg/dL) starting within 2 h of an antecedent SG <3.9 mmol/L (70 mg/dL). The severity of the RH events was calculated as area under the curve (AUC) and separately for users of multiple daily injections (MDIs), unintegrated insulin pumps, sensor augmented pumps (SAPs), and automated insulin delivery (AID), respectively. Results: Across the four groups, SAP and AID users had the highest incidence of RH (2.06 ± 1.65 and 2.08 ± 1.49 events per week, respectively) and a similar percentage of hypoglycemic events leading to RH events (41.3 ± 22.8% and 39.6 ± 20.1%, respectively). The AID users with RH events were significantly shorter compared with MDI users (122 ± 72 vs. 185 ± 135 min; P < 0.0001). Overall, severity of RH was inversely associated with more advanced technology (P < 0.001) and inversely associated (P < 0.001) with time in target range (TIR). Conclusions: Groups with insulin suspension features experienced the highest frequency of RH; however, AID users tended to experience shorter and less severe RH events. The association between the severity of RH events and TIR suggests that RH should be assessed and used in the guidance of hypoglycemia management.