1048-P: Fasting C-Peptide as a Predictor for Hypoglycemia Risk and HbA1c Reduction in Chinese T2DM Patients Switching from Premixed to Basal Insulin: A Post Hoc Analysis from the Optimization Study

Objective: To explore the predictive effect of baseline fasting C-peptide (FCP) on hypoglycemia risk, HbA1c reduction, and treatment satisfaction in Chinese T2DM individuals switching from premixed to basal insulin.

Methods: Post-hoc analysis of the single-arm, 16 weeks, phase IV OPTIMIZATION study. At 16 weeks, the study showed a mean reduction in HbA1c of 0.51% with basal insulin treatment after switching from premix. Study completers with baseline FCP testing (n=297) were stratified according to HbA1c <7.5% achievement or actual decrease at 16 weeks. In addition, hypoglycemia and patient feelings during treatment using DTSQ score were assessed. Different FCP thresholds were analyzed with Chi-square test and multivariate logistic regression analysis to test whether baseline FCP could be used to predict clinical results.

Results: When looking at efficacy alone, FCP >1.0 nmol/L could be used for predicting a higher probability to reach HbA1c <7.5% (OR=3.83, 95%CI 1.89, 7.73) and higher probability to achieve a HbA1c decrease >0.4% (OR=3.19, 95%CI 1.54, 6.59). By dividing participants using FCP dichotomy, similar results were obtained in people with FCP >0.59 nmol/L. When combined with overall hypoglycemia, both thresholds of FCP >1.0 nmol/L (OR=2.78, 95%CI 1.36, 5.68) and >0.59 nmol/L (OR=1.83, 95%CI 1.01, 3.30) predicted HbA1c <7.5% achievement without hypoglycemia. Similar results were also obtained for predicting both HbA1c<7.5% and better DTSQ score results.

Conclusion: Baseline fasting C-peptide could be used as a biomarker to predict greater HbA1c reduction, less hypoglycemia and better satisfaction in Chinese T2DM people switching from premixed to basal insulin.