Abstract: Objective To explore the correlation between erythrocyte distribution width (RDW), medium molecular fragment of osteocalcin N segment (N-MID OC)/ special sequence β carboxy-terminal peptide of collagen I (β-CTX) ratio and the risk of hip fracture in elderly women. Methods A total of 731 female patients over 60 years old who were hospitalized in Sichuan Orthopedics Hospital from January 2021 to December 2021 were selected. There were 375 cases with fracture and 358 cases without fracture. The clinical baseline data were collected. Binary logistic regression model was used to analyze the correlation between RDW-CV, N-MID OC/β-CTX ratio and hip fracture in elderly women. Results Logistic regression analysis showed that age, RDW-CV, N-MID OC/β-CTX, calcium (Ca) and phosphorus (P) levels were risk factors for hip fracture in elderly women. The values of RDW-CV and N-MID OC/β-CTX were divided into three levels in equal proportion after ordering from small to large, and the results showed that the higher the RDW-CV and the lower the N-MID OC/β-CTX ratio, the higher the risk of hip fracture in elderly women (P＜0.05). According to receiver operating characteristic curve (ROC), both single test and combined test may be used to diagnose fracture, but combined test may improve the diagnostic performance, with area under curve (AUC) of 0.729, sensitivity and specificity of 60.53% and 75.42%, respectively. Conclusions RDW-CV and N-MID OC/β-CTX ratio are associated with hip fracture in elderly women.

Key words: erythrocyte distribution width, elderly women, hip fracture, fracture risk