Using Post-bronchodilator FEV1 is Better Than Pre-bronchodilator FEV1 in Evaluation of COPD Severity

AbstractBackground: The current standards for the diagnosis and treatment of patients with COPD clearly rely on the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria based on post-bronchodilator spirometric values. However, clinical evidence for using the post-bronchodilator FEV1 in the severity classification has not been fully investigated. Methods: Patients with COPD were enrolled and followed up prospectively between October 2006 and January 2011. We compared the observed 3-year risk of all causes and respiratory mortality with the risk predicted by the pre- and post-bronchodilator percent predicted FEV1. Other important phenotypes including BMI, MMRC dyspnea scale, ECOG performance status and severe AECOPD (acute exacerbation) were also compared between the two groups. The different severity classifications of COPD, measured according the GOLD guidelines by post- and pre-bronchodilator percent predicted FEV1 were compared for prediction of mortality. Results: There were 35 deaths...