Predictive value of the early postoperative hemoglobin-to-red blood cell distribution width ratio for acute kidney injury in elderly intertrochanteric fracture patients.

ABSTRACT

BACKGROUND: Hemoglobin-to-red blood cell distribution width ratio (HRR) had great predictive value for the prognosis of malignant tumors and cardiovascular disease. However, its predictive value for the occurrence of acute kidney injury (AKI) in elderly intertrochanteric fracture patients remains unclear. This study aims to analyze the correlation between the early postoperative HRR and the risk of postoperative AKI in elderly intertrochanteric fracture patients. METHODS: We reviewed the medical records of 307 elderly intertrochanteric fracture patients in this single-center retrospective cohort study. We performed univariate analysis on the relevant parameters, and parameters with significant differences were included in the following logistic regression model for multivariate analysis. Then, we used a receiver operating characteristic (ROC) curve to evaluate the predictive value of the early postoperative HRR level for AKI in elderly intertrochanteric fracture patients. Patients were divided into a high HRR group and a low HRR group according to the cutoff point determined by ROC curve analysis. Subsequently, the relevance between postoperative HRR and AKI was further determined using propensity score matching (PSM) and inverse probability of treatment weighting (IPTW). RESULTS: The area under the curve of the early postoperative HRR for predicting postoperative AKI was 0.714 (95% CI 0.618-0.809). The cutoff value was 5.44. The sensitivity was 72.7%, and the specificity was 70.8%. Patients were divided into low HRR (⩽ 5.44) and high HRR (> 5.44) groups according to the cutoff value. PSM and IPTW analysis indicated that the risk of AKI in the low HRR group was significantly higher than that in the high HRR group in both the matched cohort (OR = 6.914, 95% CI 1.714-46.603, p = 0.016) and the weighted group (OR = 2.784, 95% CI 1.415-5.811, p = 0.040). CONCLUSIONS: Early postoperative HRR is an accurate, accessible, and economical blood test parameter that can predict the risk of postoperative AKI in elderly patients with femoral intertrochanteric fracture.