Renoprotective effect of additional sodium–glucose cotransporter 2 inhibitor therapy in type 2 diabetes patients with rapid decline and preserved renal function

AIMS/INTRODUCTION: The slope of estimated glomerular filtration rate (eGFR) decline (eGFR slope) in early‐stage type 2 diabetes patients might predict the future risk of end‐stage renal disease. Type 2 diabetes patients who show rapid progressive eGFR decline are termed rapid decliners. Several studies of rapid decliners have investigated the efficacy of sodium–glucose cotransporter 2 inhibitors (SGLT2i) in patients with advanced renal dysfunction; however, no studies, to our knowledge, have focused on patients with preserved renal function. Therefore, we investigated the efficacy of SGLT2i in rapid decliners with preserved renal function. MATERIALS AND METHODS: This study enrolled type 2 diabetes patients with baseline eGFR ≥60 mL/min/1.73 m(2) who had been treated with SGLT2i for ≥3 years. Among these individuals, we defined those with annual eGFR declines ≥5 mL/min/1.73 m(2) per year before SGLT2i administration as rapid decliners. The primary end‐point was the change in eGFR slope after SGLT2i administration. RESULTS: Among 165 patients treated with SGLT2i for ≥3 years, 21 patients were rapid decliners with preserved renal function. The mean age and eGFR at SGLT2i administration were 58.6 years and 87.1 mL/min/1.73 m(2), respectively. The mean annual eGFR slope improved significantly in those administered SGLT2i compared with the control group (−1.00 and −4.36 mL/min/1.73 m(2) per year, respectively; P < 0.001). Notably, the steeper the eGFR slope before starting SGLT2i administration, the larger the improvement of eGFR slope, which was independent of the reduction of albuminuria. CONCLUSIONS: Early intervention with SGLT2i may have renoprotective effects in type 2 diabetes patients with rapid decline and preserved renal function.