Changes in glycemic control and skeletal muscle mass indices after dapagliflozin treatment in individuals with type 1 diabetes mellitus

AIMS/INTRODUCTION: Dapagliflozin is used for individuals with type 1 diabetes, although the effect of this medication on skeletal muscle mass is not well established. In addition, there are few studies examining the effects of good glycemic control on skeletal muscle mass in type 1 diabetes patients. We investigated changes in glycemic control and skeletal muscle mass with dapagliflozin in individuals with type 1 diabetes, and the association between these changes. MATERIALS AND METHODS: This was a post‐hoc analysis of a multicenter, open‐label, non‐randomized, prospective, interventional study in individuals with type 1 diabetes. The participants received dapagliflozin at 5 mg/day for 4 weeks, and were reviewed before and after treatment. Weight‐ and height‐corrected appendicular skeletal muscle mass (ASM) were calculated as indices of skeletal muscle mass using bioelectrical impedance analysis. RESULTS: A total of 36 individuals were included in the analysis. After the 4 weeks of dapagliflozin treatment, ASM/height(2) decreased in the body mass index <23 group (P = 0.004). ASM / weight decreased in all men aged >60 years. The change in ASM / weight (%) was negatively correlated with the change in glycated hemoglobin (%;P = 0.023). The change in ASM / height(2) (kg/m(2)) was also positively correlated with the change in time within the glucose range of 70–180 mg/dL (P = 0.036). CONCLUSION: Dapagliflozin treatment of individuals with type 1 diabetes, particularly non‐obese individuals and older men, might result in loss of skeletal muscle mass. However, good glycemic control during treatment might prevent the onset and progression of sarcopenia.