Influencing factors of 1-year postoperative mortality in elderly with hip fracture and construction of a nomogram prediction model

Objective To investigate the influencing factors of 1-year postoperative mortality in elderly patients with hip fracture based on new nutritional indicators, and draw a predictive nomogram for 1-year death in these elderly patients. Methods A retrospective study was conducted on 457 elderly hip fracture patients who underwent surgical treatment in our department from January 2018 to May 2021. All of them were followed up, and the outcomes in 1 year after operation were observed. Their baseline data, mini-nutritional assessment (MNA) score, nutritional risk screening 2002 (NRS2002) score, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, serum nutritional indicators, body compositions and other new nutritional indicators were collected and analysis with 1-year mortality as observation outcome. Multivariate logistic regression analysis was used to analyze the independent risk factors of 1-year postoperative death in these elderly patients, and further R Studio software was applied to build a nomograph model to predict the risk of death. Results Of 457 elderly patients with hip fracture, 52 (11.38%) died within 1 year after operation and 405 survived. More than 3 comorbidities, age, and C-reactive protein (CRP) level were independent risk factors [OR(95%CI): 3.196(1.107~9.226), 1.152(1.083~1.225), 1.013(1.004~1.022), P < 0.05], and BMI and skeletal muscle content were protective factors [OR(95%CI): 0.766(0.671~0.874), 0.782(0.726~0.842), P < 0.05] for death within 1 year after surgery in elderly patients with hip fracture. Based on the above 5 influencing factors, a column graph was drawn and assessed with internal verification. The results showed that the C-index of model differentiation and 95%CI was 0.92 and 0.870~0.970, respectively. The correction curve indicated that the model had good consistency, indicating that the column graph model had good predictive ability. Conclusion Age, CRP, BMI, ≥3 comorbidities and skeletal muscle content are independent risk factors for death within 1 year after hip fracture in elderly patients. The nomogram model has a certain effect on predicting the 1-year mortality risk in them.