Prediction of postoperative mortality in elderly patient with hip fractures: a single-centre, retrospective cohort study

BACKGROUND: Elderly patients are at high risk for postoperative complications and increased mortality after hip fracture (HF) surgery due to frailty and co-morbidities. The prediction of postoperative outcome could be used for clinical decision making. A reliable score to predict postoperative mortality after HF surgery in this sub-population remains unavailable. METHODS: A single-centre retrospective cohort study was performed in 782 patients who were operated on for HF. Receiver Operating Characteristic (ROC)-curves were used to analyse the performance of gender, age, neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) at admission (D(0)) as prognostic factors, alone or combined with the PreOperative Score to predict PostOperative Mortality (POSPOM) in univariate and multivariate linear regression models. RESULTS: No correlation between gender, age, NLR D(0) or CRP D(0) and postoperative, intra-hospital mortality was found. The Area Under the ROC-curve (AUC) for age, male gender, NLR and CRP were 0.61 [95% confidence interval (CI) = 0.45–0.61], 0.56 [95% CI = 0.42–0.56], 0.47 [95% CI = 0.29–0.47] and 0.49 [95% CI = 0.31–0.49] respectively. Combination with the POSPOM score did not increase its discriminative capacity as neither age (AUC = 0.69, 95% CI = 0.54–0.69), gender (AUC = 0.72, 95% CI = 0.58–0.72), NLR D(0) (AUC = 0.71, 95% CI = 0.56–0.71), nor the CRP D(0) (AUC = 0.71, 95% CI = 0.58–0.71) improved the POSPOM performance. CONCLUSIONS: Neither age, gender, NLR D(0) nor CRP D(0) are suitable parameters to predict postoperative, intra-hospital mortality in elderly patients undergoing surgery for HF.