Glycemic Control and Insulin Improve Muscle Mass and Gait Speed in Type 2 Diabetes: The MUSCLES-DM Study

ObjectivesType 2 diabetes is a risk factor for sarcopenia. Evidence on the prevention of sarcopenia using blood glucose–lowering therapy is limited. We aimed to examine the relationship between changes in glycemic control and sarcopenia and the effect of antidiabetic agents against sarcopenia in patients with type 2 diabetes.DesignWe conducted an observational longitudinal study.Setting and ParticipantsIn total, 588 Japanese patients with diabetes of an ongoing multicenter study completed 1-year follow-up measurements for sarcopenia and clinical data.MethodsThe data set of the Multicenter Study for Clarifying Evidence for Sarcopenia in patients with Diabetes Mellitus (the MUSCLES-DM study) was analyzed.ResultsDuring the follow-up period, the frequency of sarcopenia marginally increased, and the means of skeletal muscle mass index (SMI), handgrip strength, and gait speed did not show any changes. However, on dividing into 5 groups depending on the degree of changes in glycated hemoglobin (HbA_1c) value, the patients with a decrease of ≥1% in HbA_1c exhibited a significant increase in SMI. Our analysis revealed similar results for gait speed but not handgrip strength. Using the multiple linear regression model, we identified that a ≥1% decrease in HbA_1c value was an independent determinant of the changes in SMI and gait speed. We also determined that insulin use at baseline was an independent factor for the changes in SMI.Conclusions and ImplicationsCorrection of poor glycemic control and use of insulin were significantly associated with the increase in skeletal muscle mass or gait speed in Japanese patients with type 2 diabetes. The current finding increases our understanding of the importance of glycemic control for the prevention of cardiovascular diseases and sarcopenia.