The Relationship Between Blood Urea Nitrogen to Creatinine Ratio and Severe Acute Exacerbation of COPD Patients: A Propensity Score Matching Study

Purpose: The blood urea nitrogen/creatinine ratio (BCR) is an effective marker for disease severity stratification. Its efficacy has been demonstrated under numerous conditions. This study aims to investigate the relationship between BCR and in-hospital mortality in intensive care unit (ICU) patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).<br /> Patients and Methods: Eligible ICU patients with AECOPD from the eICU database were included in the study. Patients were divided into high-BCR and low-BCR groups on the basis of the optimal cutoff value (22.78) of the ROC curve for predicting in- hospital mortality in AECOPD patients. Propensity score matching (PSM) was used to balance the baseline differences between the high-BCR and low-BCR groups. Multivariate logistic regression was used to analyze the relationship between BCR and in-hospital mortality in ICU patients with AECOPD. Decision curve analysis (DCA) was performed to evaluate the clinical efficacy of each model via multivariate logistic regression.<br /> Results: A total of 3399 eligible ICU patients with AECOPD were included in the study, with 1559 patients in the high-BCR group and 1840 patients in the low-BCR group. After propensity score matching (PSM), 1174 pairs of patients were successfully matched. The results of the multivariate logistic regression revealed that the in-hospital mortality rate for AECOPD patients in the high-BCR subgroup was significantly greater than that in the low-BCR subgroup in both the unmatched and matched cohorts after adjusting for multiple factors. Additionally, DCA demonstrated that the models used in the multivariate logistic regression had effective clinical utility.<br /> Conclusion: The blood urea nitrogen/creatinine ratio (BCR) is an effective predictor of in-hospital mortality in ICU patients with AECOPD. Clinicians can use BCR to identify critically ill ICU patients with AECOPD earlier and implement interventions to improve patient outcomes.