Background: SGLT2 inhibitors (SGLT2i) are used worldwide, because of their multiple benefits for patients with type 2 diabetes. The purpose of this study was to determine the efficacy and safety of SGLT2i in patients with type 1 diabetes.

Methods: Patients with type 1 diabetes attending multiple centers who had been treated with SGLT2i for >12 weeks were included in this retrospective study. Changes in body mass, insulin dose, blood test data, including HbA1c, and the frequency of adverse events were evaluated over 12 weeks. The changes in day-to-day and daily glucose variability were evaluated using continuous glucose monitoring (CGM) as the primary endpoints. Day-to-day glucose variability was evaluated using the interquartile range (P25/P75) of the ambulatory glucose data obtained using CGM.

Results: Fifty-one patients (37 female; mean age 52.7 years) were included in the analysis. HbA1c and body mass significantly decreased by 0.4% and 1.2 kg, respectively. The total insulin dose decreased by 15.6% (43.6 ± 26.2 to 36.8 ± 25.2 units/day). CGM data were obtained from 29 patients. The P25/P75 significantly decreased by 17.6 ± 20.7% during SGLT2i treatment (P<0.01). The TIR (time in range: % of readings and time 70-180 mg/dL) significantly increased (42.1% to 55.7%, P<0.01) and the TAR (time above range) significantly decreased (56.4% to 42.5%, P<0.01) although the TBR (time below range) was not affected (1.56% to 1.89%). During the observation period, 11 patients (21.2%) showed hypoglycemia. Urinary ketone bodies were detected in four patients (7.8%), but none developed ketoacidosis, urinary tract infections or dizziness.

Conclusion: SGLT2i were effective at reducing HbA1c and body mass, and were safe in this clinical study. In addition, SGLT2i improved both day-to-day and daily glucose variability in patients with type 1 diabetes. The incidence of hypoglycemia could be reduced by reducing glucose fluctuations using SGLT2i, after which the dosage could be adjusted appropriately.


K. Chiba: None. K. Cho: None. H. Kameda: None. A. Nakamura: None. Y. Shibayama: None. H. Nomoto: None. T. Atsumi: Consultant; Self; Chugai Pharmaceutical Co., Ltd., Eli Lilly Japan K.K., GlaxoSmithKline plc., Pfizer Inc., UCB Japan Co. Ltd. Speaker’s Bureau; Self; AbbVie Inc., Alexion Pharmaceuticals, Inc., Astellas Pharma Inc., Bristol-Myers Squibb, Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo, Eisai Co., Ltd., Eli Lilly Japan K.K., Gilead Sciences, Inc., Mitsubishi Tanabe Pharma Corporation, Otsuka Pharmaceutical Co., Ltd., Pfizer Inc., Takeda Pharmaceutical Company Limited, UCB Japan Co. Ltd. H. Miyoshi: Research Support; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo, Eli Lilly Japan K.K., Novo Nordisk Inc., Sumitomo Dainippon Pharma Co., Ltd., Taisho Pharmaceutical Co., Ltd. Speaker’s Bureau; Self; Astellas Pharma Inc., Boehringer Ingelheim Pharmaceuticals, Inc., Daiichi Sankyo, Eli Lilly Japan K.K., Kowa Company, Ltd., MDS CO. LTD., Mitsubishi Tanabe Pharma Corporation, Novo Nordisk Inc., Ono Pharmaceutical Co., Ltd., Sanofi K.K., Sumitomo Dainippon Pharma Co., Ltd. Other Relationship; Self; Abbott, Boehringer Ingelheim Pharmaceuticals, Inc., Kowa Company, Ltd., Mitsubishi Tanabe Pharma Corporation, Ono Pharmaceutical Co., Ltd.

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