Abstract: Objective To explore effects of muscle mass modified by different methods on physical function in old people with type 2 diabetes mellitus (T2DM). Methods A total of 248 old people with T2DM aged more than 60 years were included in the study. Levels of hemoglobin(Hb), glycosylated hemoglobin A1c(HbA1c), fasting plasma glucose (FPG), vitamin D were measured and grip strength, gait speed, timed go and up (TUG) time were assessed. Body mass index (BMI) was calculated. Furthermore, appendicular skeletal muscle mass(ASM) was assessed by dual energy X-ray absorptiometry (DXA) and were adjusted by height square (ASM/ht²) and BMI (ASM/BMI) accordingly. The influencing factors for physical function were evaluated. Results The partial correlation analysis showed that ASM/BMI was associated with grip strength, gait speed and TUG time (r=0.636, P<0.001;r=0.191, P=0.003;r=- 0.143, P=0.026; respectively), while ASM/ht² was only associated with grip strength (r=0.513, P<0.001). In a multiple logistic analysis, low ASM/BMI was associated with increased risk of low gait speed and long TUG time (OR=4.73,95%CI: 1.54-14.60,P=0.007; OR=2.92,95%CI: 1.12-7.63,P=0.029, respectively), while ASM/ht² had no significant effect on physical function. Conclusion Low ASM/BMI but not low ASM/ht² was significantly associated with poor physical function in older adults with T2DM. ASM/BMI may be a more suitable method of muscle mass correction for T2DM patients.

Key words: type 2 diabetes mellitus, muscle mass, sarcopenia, physical function