Objective: In spite of expected benefit of insulin degludec/aspart (IDegAsp), efficacy of once-daily IDegAsp compared to basal insulin has not been established. We searched for clinical factors associated with efficacy of once-daily IDegAsp.

Methods: We collected medical records of adults with type 2 diabetes under basal insulin of 3 hospitals. From the basal insulin cohort, patients were enrolled who switched to once-daily IDegAsp and continued over 6 months. Those who maintained basal insulin were selected as a control group, by Propensity-score matching with HbA1c, insulin doses, etc.

Results: The basal insulin cohort was comprised of 324 patients, and the IDegAsp group and the control were 87 patients, respectively. Baseline clinical variables and HbA1c were comparable between two groups (8.7±0.9 vs. 8.6±0.9%). After 6 months with comparable changes in insulin doses, HbA1c in the IDegAsp group was lower than that in the control (8.1±1.0 vs. 8.4±1.1%, p=0.029). With the comparable HbA1c, baseline FPG was lower in the IDegAsp (124±38 vs. 148±51 mg/dL, p<0.001). A regression analysis between FPG and HbA1c in the basal insulin cohort revealed that most participants in the IDegAsp group had lower FPG than predicted from their HbA1c. Then subgroup analysis was done according to the difference (ΔFPG) between measured FPG and predicted FPG. When compared to each control group further matched for baseline FPG, the favorable effects of IDegAsp on the reduction of HbA1c changes was significant only in the subgroup where measured FPG was severely lower than predicted FPG (98±19 vs. 140±11 mg/dL). ΔFPG was significantly correlated with fasting C-peptide (r=0.19) and glucose increment at postprandial 2 hours (r=-0.514).

Conclusion: Once-daily IDegAsp was effective than basal insulin on reduction of HbA1c in patients with lower FPG than predicted from their HbA1c, which suggested severe insulin deficiency and marked postprandial hyperglycemia.


H. Jang: None. Y. Yang: None. T. Oh: None. B. Koo: None. S. Lee: None. H. Jung: Research Support; Self; Novo Nordisk.


National Research Foundation of Korea (2019R1A2C1007397); Korean Diabetes Association (2019F-10)

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