Association between N-terminal pro B-type natriuretic peptide and short- and long-term all-cause mortality in critically ill patients with sepsis: A retrospective study based on the Medical Information Mart for Intensive Care IV database

Background Sepsis, caused by a dysregulated host response to infection, is a life-threatening condition linked to nearly one-fifth of deaths worldwide. As a biomarker of myocardial stress, N-terminal pro B-type natriuretic peptide (NT-proBNP) has gained attention for its potential association with clinical outcomes in sepsis patients. This study investigated its association with short- and long-term mortality in sepsis. Methods This retrospective observational cohort study utilized data from the Medical Information Mart for Intensive Care IV database. Sepsis patients on their first intensive care unit admission with NT-proBNP measured within 24 h were categorized into four groups based on their natural log-transformed levels. The primary endpoint was 30-day all-cause mortality (ACM), with secondary endpoints of 90-day and 1-year ACM. Cox models, Kaplan–Meier curves, restricted cubic splines (RCS), and subgroup analyses were performed to assess the relationship between log(NT-proBNP) and 30-day, 90-day, and 1-year ACM. Results The study cohort consisted of 1237 patients, with 54.41% male. The 30-day, 90-day, and 1-year ACM rates were 27.41%, 29.99%, and 31.69%, respectively. Multivariate Cox analysis showed that log(NT-proBNP) was independently associated with higher risks of 30-day ACM (hazard ratio[HR] 1.12 [95% confidence interval (CI) 1.03–1.22]; P = 0.01), 90-day ACM (HR 1.12 [95% CI 1.03–1.22]; P = 0.005), and 1-year ACM (HR 1.11 [95% CI 1.03–1.20]; P = 0.007). These associations remained robust in sensitivity analyses. The RCS curves demonstrated a linear increase in ACM risk as log(NT-proBNP) levels rose. Subgroup analyses confirmed these associations across different patient groups. Conclusion Elevated log(NT-proBNP) in critically ill sepsis patients are significantly and independently associated with higher 30-day, 90-day, and 1-year ACM, suggesting that NT-proBNP may serve as a valuable risk marker for both short- and long-term mortality in this population.