Comparison of glycemic variability between basal-bolus and premixed insulin therapy

Background: Several studies have shown that twice-daily injections of premixed insulin analogs (MIX) could achieve comparable HbA1c levels to basal-bolus (BB) therapy. However, HbA1c does not necessarily reflect short-term glycemic fluctuations that may contribute to the onset or progression of diabetic complications. Therefore, in this study, we compared MIX and BB therapies in terms of their effects on glycemic variability. Methods: We performed a crosssectional observational study of patients attending our outpatient clinics to compare the effects of two insulin regimens on glycemic variability. We recruited patients treated with MIX or BB with HbA1c < 8.4%. A total of 27 patients (11 treated with BB and 16 treated with MIX) were enrolled and wore a continuous glucose monitor (CGM) for 72 h, while continuing their usual lifestyle and insulin doses. Results: No significant differences in CGM-determined glycemic markers were observed between the two groups. However, the post-lunch duration of glucose levels > 180 mg/dL (t > 180) was significantly shorter with BB therapy (88 ± 76 min) than with MIX therapy (145 ± 54 min; p < 0.05). After classification according to HbA1c levels, markers of glycemic variability were better in patients treated with BB than in those treated with MIX in better control group. Conclusion: These results suggest that BB therapy achieves better glucose profiles than MIX therapy in patients with type 2 diabetes, particularly after lunch.