Abstract
INTRODUCTION: When switching from premixed insulin to insulin degludec/aspart (IDegAsp), IDegAsp usually starts at the same dose as the premixed insulin according to limited clinical experience or at a dose according to clinician discretion. The dose of insulin degludec used in the real world after switching has been poorly investigated. METHODS: A retrospective analysis was conducted on patients with type 2 diabetes who switched from premixed insulin to IDegAsp from October 2016 to December 2023. Repeated measures analysis of variance was used to compare changes in insulin dose, glycated hemoglobin (HbA1c), fasting blood glucose (FBG), and postprandial blood glucose (PBG) before and after switching. RESULTS: Sixty-six patients with prior low-ratio premixed insulin and 22 with prior mid-ratio premixed insulin were included. Among the low-ratio insulin users, the total daily dose of insulin degludec (IDeg) decreased by 21.43% and 19.05% at 3 and 6 months, respectively, after switching, compared with prior basal insulin dose (both p < 0.001). Conversely, among mid-ratio insulin users, the IDeg daily dose increased by 10.71% and 32.14% at 3 and 6 months, respectively, after switching, compared with prior basal insulin dose (both p < 0.001). In all patients, HbA1c levels decreased by 0.70%, FBG decreased by 1.00 mmol/l, and PBG decreased by 1.61 mmol/l after 6 months of switching (all p < 0.05); the total daily insulin dose and injection frequency significantly decreased after switching (both p < 0.05); age and disease duration did not affect IDegAsp effects on HbA1c reduction. CONCLUSIONS: In the setting of transition to IDegAsp from premixed insulin, the dose of basal insulin in the premixed formulation can be a valuable reference for adjusting insulin degludec dose. IDegAsp is superior to premixed insulin in blood glucose control with reduced total daily dose and injection frequency. IDegAsp could be the best choice for the management of diabetes in elderly patients.