The Role of Albumin Level and Blood Urea Nitrogen/ Albumin Ratio in Prediction of Prognosis of Community Acquired Pneuomonia

Background and aim: Community-Acquired Pneumonia (CAP) is an important cause of morbidity and mortality worldwide. The accuracy of scoring scales is lower regarding the evaluation of mortality and need for ICU treatment. This study aimed to evaluate the role of the albumin level and Blood urea nitrogen /Albumin (BUN/Alb) ratio in the prediction of disease severity and one-month mortality. Materials and methods: Patients hospitalized for CAP were included. Venous blood samples were obtained to measure albumin levels and calculate the ratio of BUN/Alb. The correlations of serum albumin levels and BUN/Alb ratio with the requirement of ICU, development of complications and one-month mortality were evaluated. Results: 216 patients were enrolled. Patients who needed ICU treatment had a higher BUN/Alb ratio (p=0.029). The cut-off level of BUN/Alb in prediction of ICU need was found 4.15 (sensitivity 76%, specificity 49%). Low albumin level was an independent risk factor for ICU need (OR: 5.263, 95% CI: 1.996 to 13.889, p=0.001). The cut-off level of albumin in prediction of ICU need was 3.39 g/dl (sensitivity 71%, specificity 71%). Low albumin level was independent predictive factor for the development of complications (OR: 4.902, 95% CI: 1.595 to 14.925, p=0.005). The cut-off level of albumin in prediction of development of complication was 3.44 g/dl (sensitivity 79%, specificity 69%). Conclusions: The CAP patients who have higher BUN/Alb ratio are under higher risk of the development of need for ICU treatment. Low albumin level is a more valuable predictor than BUN/Alb ratio for prognosis of CAP. *Corresponding author: Evrim Eylem AKPINAR, Chest Diseases Specialist, Ufuk University Medical Faculty, Dr. Ridvan Ege Hospital, Department of Chest Diseases, Mevlana Bulvari (Konya Yolu) No: 86-88 Balgat 06540Ankara, Turkey, Tel: +90 312 204 43 31 ; Fax: +90 312 204 40 55 ; E-mail: [email protected] Received August 20, 2013; Accepted October 18, 2013; Published October 21, 2013 Citation: AKPINAR EE, HOŞGÜN D, DOĞANAY B, GÜLHAN M (2013) The Role of Albumin Level and Blood Urea Nitrogen/ Albumin Ratio in Prediction of Prognosis of Community Acquired Pneuomonia. J Pulm Respir Med 3: 159. doi:10.4172/2161-105X. 1000159 Copyright: © 2013 AKPINAR EE, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Introduction Community-Acquired Pneumonia (CAP) is an important cause of morbidity and mortality worldwide [1]. The mortality rate of CAP ranges from less than 5% among outpatients to 12% among hospitalized patients [2]. The need for an intensive care unit (ICU) is also an important problem for clinicians to overcome during the course of CAP [3,4]. CURB-65 (confusion, urea nitrogen, respiratory rate, blood pressure, ≥ 65 years) and Pneumonia Severity Index (PSI) are the most frequently used scoring scales to assess the disease severity [5,6]. These scoring tools are useful to decide between hospitalization and outpatient treatment with an oral antibiotic. However, their accuracy is lower regarding the evaluation of mortality and need for ICU treatment [4,7]. In recent years, the role of several biomarkers, such as C-Reactive Protein (CRP) and procalcitonin, have been studied to predict the severity and prognosis of CAP and its correct diagnosis and microbiological etiology [8]. Serum albumin concentration has been used as an indicator of nutritional status for years [9]. Hypoalbuminemia was related with poor outcome in several clinical conditions, including CAP [9-11]. In a recent study by Lee et al., it was reported that albumin was associated with 28-day mortality in patients hospitalized with a CAP diagnosis [12]. The inflammatory reaction was reported as a primary reason for hypoalbuminemia in elderly patients with CAP [13]. The Blood Urea Nitrogen (BUN) level is an important biochemical parameter showing renal hypoperfusion. It is one of the contributing parameters for both the CURB-65 and PSI severity scoring scales. Previous studies have shown that patients with CAP who had higher BUN levels [14,15] and lower albumin levels [6,15] had higher mortality rates. It has recently been reported that the BUN/Albumin (BUN/Alb) ratio was an independent predictor for both mortality and the severity of CAP [16]. This study aimed to evaluate the role of the albumin and BUN/Alb ratio in the prediction of development of complications, need of ICU and one-month mortality. The secondary end-point of the study was to evaluate other factors affecting development of complications, need of ICU an one-month mortality. Materials and Methods The study included 216 consecutive patients hospitalized for CAP between the dates of January 2011 and June 2012. This was a prospective observational study. Patients who were ≥ 18 years, admitted from the community, had at least two clinical signs and symptoms related to pneumonia (fever > 38oC, cough, chest pain, dyspnea, or crackles on auscultation), and presented new infiltration on chest radiography were included in the study. Patients were excluded if they were immunocomprimised (i.e., using immunosuppressive therapy, having a human immunodeficiency virus infection, malignancy, or undergoing chemotherapy), had been hospitalized and/or used any antibiotic in last two weeks, or had chronic renal or liver failure. The design of the study is shown in Figure 1. The study was approved by the local ethics committee, and informed consent was obtained from all patients included in the study.