Analysis of bone mineral density and bone metabolism in elderly hip fracture patients of different genders

Objective To understand changes and characteristics of bone mineral density(BMD)and early-stage bone turnover biochemical markers in elderly hip fracture patients of different genders. Methods This was a retrospective cohort study.A total of 1 161 elderly patients with hip fractures hospitalized in Beijing Jishuitan Hospital from May 2015 to December 2017 were enrolled.Based on gender, patients were divided into the female group(n=831)and the male group(n=330). Clinical data, BMD, serum type I procollagen amino terminal propeptide(P1NP), and 25-hydroxyvitamin D3 [25-(OH)VD3], type I collagen cross-linked carboxy terminal peptide beta degradation products(β-CTX), osteocalcin(OC)and parathyroid hormone(PTH)were measured and compared between the two groups. Results Of the 1 161 elderly patients with hip fractures, 831 were female and 330 were male.The BMD of the lumbar vertebrae and the total hip in the female and male groups showed that 30.4%(353/1 161)and 6.8%(79/1 161)had T≥-1.0 SD respectively; 36.6%(425/1 161)and 44.7%(519/1 161)had -2.5 SD 0.05). The levels of tP1NP, β-CTX, OC and PTH in females were higher than those in males, and the level of 25-(OH)VD3 was lower than that in males(all P<0.05). As the T value decreased, β-CTX and OC increased and 25-(OH)VD3 decreased accordingly(all P<0.05). Conclusions With the increase of age, the BMD T value in elderly patients with hip fractures shows a downward trend, but its decline in women is faster and earlier.Overall, the BMD T value is not sensitive enough for osteoporosis diagnosis or hip fracture prediction in the elderly, especially in men.In the early stage of fractures, the bone turnover biochemical markers show varying degrees of change, and bone resorption and bone formation are both reduced.The significance of OC, β-CTX and VD levels in early bone metabolic abnormalities requires further study. Key words: Osteoporosis; Hip fractures; Bone density