Comparison of Glycemic Variability in Patients with Type 2 Diabetes Given Sitagliptin or Voglibose: A Continuous Glucose Monitoring-Based Pilot Study

Objective: This study compared glycemic variability in patients with type 2 diabetes given sitagliptin or voglibose. Patients and Methods: Seventeen type 2 diabetes patients were given sitagliptin 50 mg/day or voglibose 0.9 mg/day for 2 months and were hospitalized for a 4-day evaluation by continuous glucose monitoring (CGM). On discharge, they were crossed over to the other regimen for 2 months of treatment/4 days of evaluation. The CGM data were used to compare each parameter for glycemic variability. Results: The average glucose levels with sitagliptin and voglibose were significantly different at 138.6 and 152.6 mg/dL for 24 h (P = 0.014) and 147.2 and 160.9 mg/dL for during daytime (P = 0.050), respectively. The patients' glucose levels with sitagliptin and voglibose were significantly different at 125.3 and 139.7 mg/dL before breakfast (P = 0.015) and 112.7 and 131.4 mg/dL before lunch (P = 0.049), respectively. The time from before meal to postprandial peak glucose levels was significantly longer after dinner with voglibose than with sitagliptin (91.5 and 122.3 min, respectively; P = 0.012). All of the slopes of glucose elevation were significantly lower with voglibose after each meal, with that after breakfast, lunch, and dinner being 1.16 and 0.86 mg/dL/min (P = 0.031), 0.70 and 0.45 mg/dL/min (P = 0.048), and 1.06 and 0.73 mg/dL/min (P = 0.028), respectively. Conclusions: This CGM-based pilot study revealed that sitagliptin significantly lowered 24-h and daytime mean glucose levels and glucose levels before breakfast and lunch compared with voglibose, whereas the time from before dinner to peak postprandial glucose levels was significantly longer, and the slope of postprandial elevation of glucose level was significantly lower after each meal, with voglibose compared with sitagliptin.