Abstract: Objective To investigate the predictive value of neutrophil to lymphocyte ratio (NLR) on admission for prognosis in elderly patients with hip fracture. Methods A total of 725 consecutive patients were retrospectively enrolled in this study from January 2014 to December 2019. Clinical data such as age, gender, fracture information, treatment and laboratory tests were collected. NLR was calculated based on the blood routine result on admission, and the receiver operating characteristic (ROC) curve was used to determine the optimal cut-off value of NLR. Patients were divided into low NLR group and high NLR group. Survival situation was obtained from telephone follow-up, and the survival curves of patients were plotted using the Kaplan-Meier method in high NLR and low NLR groups. Cox proportional hazard model was used to analyze the risk factors affecting the prognosis. Results The optimal cut-off value of NLR was 10.08. Patients were divided into low NLR group (NLR≤10.08, n=520) and high NLR group (NLR＞10.08，n=205). The median follow-up time was 34.64 months (12~89 months), of which 45 (6.21%) died within 30-day, 105 (14.48%) in 6-month and 149 (20.55%) in 1-year. Compared with low NLR group, high NLR group showed higher fatality rates at 30-day, 6-month and 1-year (all P< 0.05). Multi-factor Cox regression analysis showed that high NLR value, male, Charlson comorbidity index (CCI) ≥1, conservative treatment, reduced albumin and elevated serum creatinine were independent risk factors for the 1-year mortality in elderly hip fracture patients (all P<0.05). Conclusion The NLR value of admission can be used as a clinical indicator to predict the prognosis in elderly patients with hip fracture.

Key words: hip fractures, prognosis, death, proportional hazards models, aged, neutrophil/lymphocyte ratio