Vitamin D Deficiency and Sarcopenia in Hip Fracture Patients

BACKGROUND: Vitamin D plays a critical role in the proliferation and differentiation of skeletal muscle and bone metabolism. We compared the prevalence of vitamin D deficiency in elderly patients undergoing hip fracture surgery (HFS) with those undergoing elective primary total hip arthroplasty (THA). We also evaluated the association between vitamin D deficiency and sarcopenia. METHODS: This prospective study included 70 patients in the HFS group, and 100 patients in the elective THA group. The HFS group included 42 women, while the elective THA group included 74 women. The mean age in the HFS and elective THA groups was 79.8 and 75.4 years, respectively, and the mean preoperative Koval score was 2.1 and 2.3, respectively. Serum 25-hydroxy-vitamin D3 levels were measured by I125 radioimmunoassay. Bone mineral density and appendicular skeletal muscle mass (ASM) were measured using dual X-ray absorptiometry. Sarcopenia index was calculated by dividing ASM (kg) by the body mass index (kg/m(2)). Sarcopenia was diagnosed when the sarcopenia index was <0.789 in men and <0.512 in women. RESULTS: Serum vitamin D levels were lower, and the percentages of patients with vitamin D insufficiency and deficiency were higher in the HFS group than in the elective THA group. In the HFS group, the prevalence of sarcopenia was higher in men (57%, 16/28) than in women (29%, 12/42; P=0.025). CONCLUSIONS: Vitamin D deficiency was more prevalent in patients undergoing HFS than in patients undergoing elective THA. Among patients undergoing HFS, vitamin D deficiency was more prevalent in sarcopenic than in non-sarcopenic patients.