The predictive value of NT-proBNP/ALB ratio for in-hospital pericardial effusion in young acute myocardial infarction patients

Background – The incidence of acute myocardial infarction (AMI) in young adults (<45 years) is increasing. Pericardial effusion (PE) is a notable complication reflecting hemodynamic instability and severe inflammation; however, sensitive biomarkers for early risk stratification in this specific demographic remain under-investigated. The N-terminal pro-B-type natriuretic peptide to albumin ratio (NT-proBNP/ALB) integrates hemodynamic load with inflammatory-nutritional status, yet its prognostic utility for PE in young AMI patients is unexplored. Methods – This retrospective observational study enrolled 1, 974 young AMI patients admitted to the First Affiliated Hospital of Xi'an Jiaotong University between January 2018 and October 2025. Patients were categorized into PE and non-PE groups based on echocardiographic findings. Multivariate logistic regression was utilized to identify independent predictors. The incremental predictive value of the log-transformed NT-proBNP/ALB ratio (lg BNP/ALB) and Plateletcrit (PCT, a platelet mass marker) was evaluated using Receiver Operating Characteristic (ROC) curves, Net Reclassification Improvement (NRI), and Integrated Discrimination Improvement (IDI). Results – In-hospital PE occurred in 7.1% (141/1, 974) of the cohort. Multivariate analysis identified lg (NT-proBNP/ALB) (adjusted OR: 3.23, 95% CI: 1.30–5.78, P < 0.001) and PCT (adjusted OR: 1.87, 95% CI: 1.08–3.23, P = 0.025) as independent risk factors, alongside STEMI, LVEF, eGFR, and total cholesterol. The incorporation of lg (NT-proBNP/ALB) and PCT into a baseline clinical model significantly improved the Area Under the Curve (AUC) from 0.718 to 0.849 (P < 0.001). Furthermore, reclassification analyses confirmed significant improvements in risk stratification, with a categorical NRI of 0.2198 (P < 0.001) and an IDI of 0.1116 (P < 0.001). Conclusion – The admission NT-proBNP/ALB ratio and PCT were independently associated with in-hospital pericardial effusion in young AMI patients and provided incremental value for early risk stratification beyond conventional clinical indicators.