Preoperative Blood Urea Nitrogen-to-Serum Albumin Ratio for the Prediction of In-hospital Mortality in Patients who Underwent Emergency Surgery for Acute Type A Aortic Dissection

Abstract

Abstract Background Blood urea nitrogen (BUN) and serum albumin (SA) are related to mortality in patients with cardiovascular diseases, such as acute aortic dissection. However, there are no data on the relationship between BUN-to-albumin ratio (BA-R) and mortality in patients with acute type A aortic dissection (ATAAD). Thus, the aim of this study was to evaluate the prognostic value of BA-R for the prediction of in-hospital mortality in patients who underwent emergency surgery for ATAAD. Methods Patients who were diagnosed with ATAAD and underwent emergency surgery within 48 h of onset at our hospital between January 2015 and December 2021 were included in this study. The primary endpoint of this study was postoperative in-hospital mortality (POIM). The data of the survivors and non-survivors were retrospectively compared. Univariate and multivariable logistic regression analyses were performed to investigate the association between BA-R and POIM. Results A total of 557 patients with ATAAD were enrolled in this study. Of these, 505 survived and 52 did not. The preoperative BA-R of the non-survivor group was significantly higher than that of the survivor group (0.27 [0.18, 0.46] vs. 0.12 [0.10, 0.16] mmol/g; P < 0.001). Univariate regression analysis showed that preoperative BA-R ≥ 0.155 mmol/g, serum creatinine level ≥ 96.3 µmol/mL, SA level < 37.05 g/L, D-dimer level ≥ 8.21 µg/mL, age ≥ 56 years, myocardial ischemia, cerebral ischemia, and aortic clamp time ≥ 49.6 min were risk factors for POIM. In addition, multivariable regression analysis showed that preoperative BA-R ≥ 0.155 mmol/g was a risk factor for POIM (odds ratio, 6.815 [3.582–12.964]; P < 0.001). Receiver operating characteristic curve indicated that the cut-off point for preoperative BA-R was ≥ 0.155 mmol/g (area under the curve = 0.874). The sensitivity and specificity of preoperative BA-R in predicting the POIM of patients who underwent emergency surgery for ATAAD were 84.6% and 71.3%, respectively (95% confidence interval, 0.829–0.919; P < 0.001). Conclusion Preoperative BA-R is a simple, rapid, and potentially useful prognostic indicator of POIM in patients with ATAAD.