Predicting mortality rate in elderly patients operated for hip fracture using red blood cell distribution width, neutrophil-to-lymphocyte ratio, and Nottingham Hip Fracture Score.

Abstract

In this study, we aimed to compare the neutrophil-tolymphocyte ratio (NLR), red blood cell distribution width (RDW), and Nottingham Hip Fracture Score (NHFS) according to one-year mortality estimation after hip fracture surgery in elderly. Between January 2015 and December 2019, a total of 190 elderly patients (63 males, 127 females; mean age: 82.8±6.1 years; range, 70 to 98 years) who were diagnosed with collum femoris fractures treated with hemiarthroplasty were included. The cohort was divided into two groups with NHFS ≤4 and >4 as the low- and high-risk patients, respectively and one-year mortality was assessed for both groups. The RDW was evaluated with blood values sampled on the day of admission. A cut-off of 14.5% was considered for the RDW values. The NLR values calculated on admission (NLR-D0) and postoperative Day 5 (NLR-D5) were considered the primary outcome measures. A total of 46 patients (24.2%) developed any type of complication. The NLR values higher than 5 on Days 0 and 5 were more frequently seen in the complicated patients (p=0.0016 and p<0.001). There were significantly more patients with higher RDW values (>14.5%) in the complicated group (p<0.001). The median NHFS and the rate of patients with NHFS >4 were significantly higher in the complicated patients (p<0.001 for both). The NHFS value higher than 4 had a sensitivity of 87.7% and specificity of 84.0% in predicting mortality (area under the curve [AUC]=0.910, 95% confidence interval [CI]: 0.860-0.947, p<0.001). Estimation of mortality using an RDW cut-off value of >14.5 showed 87.7% and 80.0% sensitivity and specificity, respectively (95% CI: 0.789-0.904, p<0.001). The AUC of the NLR Day 5 using a cut-off value of >6.8 was 0.953 for the prediction of mortality (95% CI: 0.912-0.978, p<0.001). Age, NLR Day 5 (>5), RDW (>14.5%) and NHFS (>4) were strongly associated with mortality prediction. The NHSF and RDW values had the highest and similar sensitivity merit, while the highest specificity was in NLR-D5. Therefore, NLR, RDW and NHFS values can be used to classify risk factors in estimating oneyear mortality rates in elderly patients operated for hip fractures. A multidisciplinary approach should be standardized in determining the risk factors before treatment in patients with hip fractures and in planning appropriate treatment for this risk.