Study on the relationship between vitamin D, grip strength and muscle mass in elderly diabetic patients

Objective To study the relationship between vitamin D level and muscle mass and grip strength in elderly patients with type 2 diabetes mellitus (T2DM). Methods From May 2016 to January 2018, 201 patients with type 2 diabetes mellitus aged ≥ 60 who were admitted to the Department of endocrinology of Xuanwu Hospital were selected for prospective study. According to 25-hydroxyvitamin D level(25(OH)D), the patients were divided into the vitamin D deficiency group (25(OH)D<20 μg/L, 140 cases) and the non-deficiency group (20 μg/L≤25(OH)D<70 μg/L, 61 cases). The grip strength, walking speed and muscle mass of upper and lower limbs were measured.Physical examination and laboratory examination were carried out. Results There was no significant difference between the two groups (P>0.05). The grip strength, upper limb and lower limb muscle contents in the non deficiency group were significantly higher than those in the deficiency group ((33.49±9.43) kg vs.(29.59±10.30) kg, (4.99±1.09) kg vs.(4.57±1.11) kg, (15.69±3.10) kg vs.(14.54±3.03) kg, P=0.01, 0.015, 0.017). Multivariate logistic regression analysis showed that vitamin D deficiency was independently related to grip strength and lower limb muscle mass(OR=1.286, 95% CI: 1.197-1.346, P<0.01; OR=1.231, 95%CI: 1.102-1.283, P<0.05). Conclusion Vitamin D deficiency is a risk factor for the decrease of grip strength and lower extremity muscle mass in elderly patients with type 2 diabetes. Key words: Type 2 diabetes; Vitamin D; Grip; Muscle mass