Evaluation of Serum 25‐Hydroxyvitamin D(3) and Bone Mineral Density in 268 Patients with Hip Fractures

OBJECTIVE: The aim of the present study was to evaluate the relationship among vitamin D nutritional status, bone mineral density, and other factors in elderly patients with brittle hip fractures. METHODS: The present study was a retrospective analysis of 268 patients, 102 men (38.06%) and 166 women (61.94%), with brittle hip fractures admitted to the Hip Joint Center of Tianjin Hospital from February 2016 to June 2018. The median age of the patients was 74 years (range, 50–93 years). The patients were divided into three groups based on age: ≤69 years, 70–79 years, and ≥80 years. Serum 25‐hydroxyvitamin D(3) (25(OH) D(3)), parathyroid hormone (PTH), body mass index (BMI), and bone mineral density (BMD) of the lumbar spine, femoral neck, and hip were measured and statistically analyzed. RESULTS: The median serum 25(OH)D(3) level of patients was 9.90 (range, 2.60–42.70) ng/mL; the proportion of deficiency was 89.18% and the deficiency was severe in 136 cases (49.25%). The proportion of vitamin D deficiency was significantly lower in men than in women (P = 0.013). With the increase of age, 25(OH)D(3) levels gradually decreased (P = 0.044) and PTH levels gradually increased (P < 0.001). There was significantly negative correlation (P < 0.001) between the levels of serum 25(OH)D(3) and PTH. There were 200 cases (74.63%) in which T‐values of BMD were less than −2.5 in any part of the lumbar vertebrae, femoral neck, and hip. T‐values in 74 cases (27.61%) were less than −2.5 in all three parts. The T‐values of BMD in men were significantly higher than those in men (P < 0.001). With the increase of age, the femoral neck BMD in men gradually decreased (P = 0.016), and the femoral neck and hip BMD in female gradually decreased (P‐value was 0.001 and 0.003, respectively). Multivariate analysis suggested that gender and BMI were independent risk factors for BMD, and vitamin D deficiency affected BMD. CONCLUSION: Vitamin D deficiency is common in patients with brittle hip fractures, especially in women. With the increase of age, vitamin D continues to decrease and PTH increases. The decrease of BMD in patients with hip fractures is the result of a combination of age, gender, BMI, and vitamin D content.