Low haemoglobin at admission is associated with mortality after hip fractures in elderly patients

Abstract

Aims Low haemoglobin (Hb) at admission has been identified as a risk factor for mortality for elderly patients with hip fractures in some studies. However, this remains controversial. This study aims to analyze the association between Hb level at admission and mortality in elderly patients with hip fracture undergoing surgery. Patients and Methods All consecutive patients (prospective database) admitted with hip fracture operated in a tertiary hospital between 2012 and 2016 were analyzed. We collected patient characteristics, time to surgery, duration and type of surgery, comorbidities, Hb at admission, nadir of Hb after surgery, the use and amount of red blood cells (RBCs) transfusion products, postoperative complications, and death. The main outcome measures were mortality at 30 days, 90 days, 180 days, and one year after surgery. Results We included 829 patients; the mean age was 81 years (sd 11). Mortality at 30 days, 90 days, 180 days, and one year was 5.7%, 12.3%, 18.1%, and 23.5%, respectively. The highest mortality was observed in patients aged over 80 years (162/557, 29%) and in male patients (85/267, 32%). Survival at 90 days, 180 days, and one year after surgery was significantly lower in patients with a Hb level below 120 g/l at admission. In multivariate analysis, Hb level below 120 g/l at admission was found to be an independent factor associated with mortality (adjusted hazard ratio (aHR) 1.68 (95% confidence interval (CI) 1.22 to 2.31); p = 0.001), along with age (aHR 1.06 (95% CI 1.04 to 1.06); p < 0.001), male sex (aHR 2.19 (95% CI 1.61 to 2.96); p < 0.001), and need for RBC transfusions (aHR 1.10 (95% CI 1.02 to 1.19); p = 0.01). Conclusion Our results suggest that low Hb at admission along with age and RBC transfusions is significantly associated with short- and long-term mortality after hip fracture surgery, independently of comorbidity confounders. Further studies should be performed to understand how preoperative Hb could be taken into account in perioperative management. Cite this article: Bone Joint J 2019;101-B:1122–1128.