Blood urea nitrogen to albumin ratio as a predictive factor for pneumonia: A meta-analysis

Background Pneumonia remains a substantial cause of mortality worldwide. The need for markers that better categorize patients is growing. We have performed a meta-analysis of Blood Urea Nitrogen to Albumin (BUN/ALB) ratio as a predictive factor regarding patients with pneumonia. Methods Three researchers systematically searched MEDLINE (1966-2021), Clinicaltrials.gov (2008-2021), Cochrane Central Register of Controlled Trials (CENTRAL) (1999-2021), Google Scholar (2004-2021) databases using a structured algorithm. Included studies contained patients with various types of pneumonia. The articles were assessed using the Quality Assessment of Diagnostic Accuracy tool. Results For more than 1900 patients with various types of pneumonia the pooled sensitivity, specificity and AUC were: 0.551, 0.892, 0.717. The optimal cutoff point was calculated at 13.290. Specificity of BUN/ALB ratio is higher than 0.85 in all subgroups and outcomes, making this ratio a great marker for ruling in patients with high risk of poor prognosis. Poor prognosis outcomes included ICU admission or death. Conclusions Regarding CAP patients we calculated an optimal cutoff of BUN/ALB ratio at 15.946 with a sensitivity of 0.587 and a specificity of 0.926 and an AUC equal to 0.732. Future studies are needed in order to assess its value in more patients without community acquired pneumonia.