Chronic kidney disease as a risk factor for severe preoperative anemia and heart failure in elderly patients with hip fracture: a single-center retrospective cohort study

Background Patients with chronic kidney disease (CKD) are prone to hip fractures and have a worse preoperative prognosis than patients without CKD. However, few studies have examined this issue by directly comparing patients with and without CKD. Methods We conducted a retrospective analysis of hip fracture patients ≥ 65 years of age who attended a level 1 trauma centre in China from January 2017 to December 2020. The CKD and non-CKD groups were matched 1:1 using the propensity score matching (PSM) method. Demographic data, comorbidities and preoperative complications were collected from the hospital's electronic medical records for both groups of patients. Patients with preoperative heart failure and anemia were classified into two classes based on different B-type natriuretic peptide (BNP) and haemoglobin (Hgb) levels. The above data were compared between the two groups of patients. The association between CKD and preoperative heart failure and anemia was assessed using univariate and multivariate logistic regression and subgroup analysis. Results We finally included 126 patients with CKD and 126 patients without CKD. The incidence of both preoperative heart failure (66.7% vs. 47.6%) and anemia (61.4% vs. 38.6%) was higher in CKD patients than in non-CKD patients. Mild heart failure (BNP < 500pg/ml) and severe heart failure (BNP ≥ 500pg/ml), mild anemia (Hgb ≥ 9.0g/dL) and severe anemia (Hgb < 9.0g/dL) were statistically different between the two groups (P < 0.05). By logistic regression analysis, patients with CKD were risk factors for severe heart failure (OR, 2.773; 95% CI, 1.299–5.922) and severe anemia (OR, 4.702; 95% CI, 1.982–11.157). After subgroup analyses, the above conclusions remain valid. Conclusion Patients with CKD have a higher risk of severe heart failure and anemia preoperatively than non-CKD patients. Clinicians should strengthen preoperative management of such patients and make full preparations for the prevention of serious complications.