Can C-reactive protein-based biomarkers be used as predictive of 30-day mortality in elderly hip fractures? A retrospective study

BACKGROUND: C-reactive protein-to-lymphocyte ratio (CLR), C-reactive protein/albumin (CRP/ALB), and CRP are prognostic factors for outcome and survival in oncology and digestive surgery. CLR has not been studied for the prediction of mortality in hip fracture. The aim of this study is to investigate whether there is an association between pre-operative CLR, CRP/ALB, and CRP levels in patients with hip fracture and patient survival. METHODS: The medical reports of the patients who underwent surgery with a diagnosis of hip fracture in our hospital between January 2016 and December 2019 were retrospectively reviewed. The patients were divided into two groups (Group E: Those who died within 1 month and Group S: Those who died after the 1(st) month or those who survived). A total of 19 parameters, namely, included “ blood parameters including hemoglobin, C-reactive protein, albumin, lymphocytes, neutrophils, monocytes, platelets, PLR, NLR, LMR, CLR CRP/ALB ratios, gender, American Society of Anesthesiologists, Charlson Comorbidity Index, delirium, infections, repeated surgeries, and type of anesthesia were evaluated preoperatively and on the post-operative 2(nd) and 5(th) days and 1 month. RESULTS: A total of 165 patients with the mean age of 83.09±8.52 years who met the inclusion criteria were studied. The pre-operative means of CRP, neutrophil count, CLR ratio, and CRP/ALB ratio were statistically significantly higher in Group E than in Group S (p=0.016, p=0.023, p=0.035, and p=0.044, respectively). The univariate regression analysis showed that age, pre-operative Hb level, CRP, and CRP/ALB ratio were significant predictors of the 1-month mortality (ß=−0.335, p=0.049; ß=0.411, p=0.028; ß=3.632, p=0.007; and ß=−3.280, p=0.008; respectively). When we performed the ROC curve analysis, the CRP/ALB ratio had the highest AUC, with the highest sensitivity and specificity. The cutoff value of CRP/ALB ratio was found to be 12.42. CONCLUSION: We found that the pre-operative CRP/ALB ratio is an important parameter for predicting the first 30-day mortality in elderly patients with intertrochanteric femur fractures. For this reason, we recommend that CRP and albumin be checked in preparation for routine pre-operative anesthesia.