The BNP-to-Albumin Ratio (BAR) as a Predictor of All-Cause Mortality in Elderly Patients with Atrial Fibrillation

Background: This study aimed to evaluate the prognostic value of the BNP-to-albumin ratio (BAR) for all-cause mortality in AF patients aged ≥ 60 years. Methods: This single-center retrospective study included clinical data from 1458 AF patients treated at the First Affiliated Hospital of Kunming Medical University between December 2019 and December 2023. Using the optimal cutoff value determined by the restricted cubic spline, patients were divided into a low BAR group (BAR < 6.05) and a high BAR group (BAR ≥ 6.05). The discriminatory performance of the BAR and various predictive models was evaluated and compared using Kaplan‒Meier survival curves, Cox proportional hazards regression models, and receiver operating characteristic (ROC) curve analysis. No external validation was performed. Results: The study ultimately included 842 patients with AF. Kaplan‒Meier analysis revealed that among elderly AF patients, the all-cause mortality rate was higher in the high-BAR group. Multivariate Cox regression analysis revealed that the BAR is an independent predictor of all-cause mortality. The area under the ROC curve (AUC) for predicting all-cause mortality was 0.778, indicating the superior predictive performance of the BAR compared with that of individual BNP and albumin levels. Conclusion: In elderly patients with AF, high BAR levels are independently associated with an increased risk of all-cause mortality, suggesting that BAR may serve as a potential prognostic biomarker.