Background and aim: A variation of the response to Sodium glucose co-transporter 2 (SGLT2) inhibitors with age has not been investigated in patients with diabetes. The aim of this study was to assess renal threshold of glucose (RTg) before and after administration of an SGLT2 inhibitor in young adult patients (≤40 years) and older adult patients (>40 years) with type 2 diabetes (T2DM).
Subjects and methods: Twenty Japanese patients with T2DM were enrolled. Baseline data were obtained on the first day and dapagliflozin (5 mg) was administered at 6:00 on the second day. Glucose excursions were assessed by continuous glucose monitoring and urine samples were collected every hour during the daytime (7:00 to 15:00) on both days. RTg was estimated from the regression line of the scatter plot of the hourly mean glucose concentrations.
Results: After a single dose of dapagliflozin, RTg decreased from 121.5 to 6.1 mg/dl in the young adult group and from 151.0 mg/dl to -15.8 mg/dl in the older group. After dapagliflozin, the slope of the regression line was significantly steeper in the young adult group.
Conclusion: Dapagliflozin was more effective in young patients because they showed a larger response of urinary glucose excretion.
Keywords: SGLT2 inhibitor; continuous glucose monitoring; dapagliflozin; renal threshold of glucose; type 2 diabetes.