The association between blood urea nitrogen to creatinine ratio and mortality in patients with upper gastrointestinal...

Azotaemia is commonly identified among patients with upper gastrointestinal bleeding (UGIB) due to absorption of blood products in the small bowel. Previous studies have found blood urea nitrogen-to-creatinine (BUN/Cr) ratio to be significantly elevated among patients UGIB bleeding compared to patients with lower GI bleeding. However, no studies have explored the relationship between BUN/Cr ratio and mortality. This study is aimed at investigating how BUN/Cr ratio relates to outcomes for UGIB patients.

This study was conducted prospectively at a university-affiliated teaching hospital with approximate 70,000 annual emergency department (ED) visits. Data from a total of 258 adult UGIB patients were collected between March 1, 2011 and March 1, 2012. Cox regression analysis was used to identify risk factors for 30-day mortality.

Malignancy and Rockall score were associated with increased risk of 30-day mortality (Unadjusted hazard ratio (HR): 3.87, 95% CI: 1.59-9.41, p = 0.0029; HR: 1.31, 95% CI: 1.02-1.71, p = 0.0476, respectively). However, BUN/Cr > 30 was associated with lower risk of 30-day mortality (HR: 0.32, 95% CI: 0.11-0.97, p = 0.0441).

A BUN/Cr ratio of >30 was found to be an independent risk factor for mortality and may be useful for pre-endoscopic assessment. Development of future risk scoring systems might warrant consideration of including BUN/Cr ratio as a parameter for estimating risk.