The relationship between serum NT-pro BNP and the severity of the COPD exacerbation

Introduction: COPD is a common preventable disease characterized by airflow limitation that is not completely reversible.Acute exacerbation is prominent and serious features of COPD. Acute Exacerbation of COPD leads to hospitalization and concomitant with morbidity and mortality .The ventricular dysfunction increases serum Brain Natriuretic Peptide(BNP)  . This study was conducted to evaluate the relationship between serum N-terminal pro b-type natriuretic peptide (NT-pro BNP) level and the severity of chronic obstructive pulmonary disease (COPD) exacerbation. .   Materials and Methods: This cross-sectional study was performed among 140 patients with COPD exacerbation referred to Imam Reza Hospital affiliated to Mashhad University of Medical Sciences, Mashhad, Iran from March 2016 to December 2017  . The patients were asked about the number of exacerbations over the past year including the recent attack. The severity of COPD was determined by the measurement of forced expiratory volume in 1 second by spirometery and level of hypoxemia by pulse oximetery. Data analysis was performed using SPSS software, version 20. Results: Regarding the results, COPD was more prevalent in males. The mean age of the patients was  57.60±9.76years old. There was a significant direct correlation between mean serum level of NT-pro BNP and age (P=0.01). Although mean serum NT-pro BNP level was higher in females patients (5.70±0.96) than males (5.66±1.24), no significant correlation was observed between mean serum NT-pro BNP level and gender (P=0.8). The most common chief complaints of the patients were dyspnea (97.9%), cough (88.9%), and phlegm (81.9%). There was no significant relationship between serum NT-pro BNP levels and the length of stay in hospital (P=0.1). However, there was a significant relationship between mean serum level of NT-pro BNP and COPD exacerbation (P=0.004). The mean serum level of NT-pro BNP was higher in the patients with more than two exacerbations over the last year in comparison to the other  patients. Additionally, there was a significant direct relationship between mean serum level of  NT-pro BNP and the severity of COPD (P=0.009). Moreover, a significant direct relationship was found between serum NT-pro BNP level and hypoxemia ( SpO2