Association between Blood Urea Nitrogen Level and In-Hospital Mortality in Patients with Acute Myocardial Infarction and Subsequent Gastrointestinal Bleeding

Abstract

Background: Limited studies have explored the association between blood urea nitrogen (BUN) levels and in-hospital mortality in patients with acute myocardial infarction (AMI) and subsequent gastrointestinal bleeding (GIB). Our objective was to explore this correlation. Methods: 276 individuals with AMI and subsequent GIB were retrospectively included between January 2012 and April 2023. The predictive value of BUN for in-hospital mortality was assessed through receiver operating characteristic (ROC) curve. Logistic regression models were constructed to assess the relationship between BUN and in-hospital mortality. Propensity score weighting (PSW), sensitivity and subgroup analyses were used to further explore the association. Results: Fifty-three (19.2%) patients died in the hospital. BUN levels were higher in non-survivors compared with the survivors [(11.17 ± 6.17) vs (8.09 ± 4.24), p = 0.001]. The ROC curve suggested that the optimal cut-off for BUN levels to predict in-hospital mortality was 8.45 mmol/L (AUC [area under the ROC curve] 0.678, 95% confidence interval [CI] 0.595–0.761, p < 0.001). Multivariable logistic regression showed that elevated BUN levels (≥8.45 mmol/L) were positively association with in-hospital mortality (odds ratio [OR] 4.01, 95% CI 1.55–10.42, p = 0.004). After PSW, sensitivity and subgroup analyses, the association remained significant. Conclusions: Elevated BUN levels were associated with in-hospital mortality in patients with AMI and subsequent GIB.

Keywords

• gastrointestinal bleeding
• blood urea nitrogen
• risk stratification
• acute myocardial infarction