COPD in chronic heart failure: less common than previously thought?

Abstract Background Using a fixed ratio of forced expiratory volume in 1 s to forced vital capacity (FEV 1 /FVC)  Objective The aim of this study was to determine COPD prevalence in patients with chronic HF according to two definitions of airflow obstruction. Methods Spirometry was performed in 187 outpatients with stable chronic HF without pulmonary congestion who had a left ventricular ejection fraction Results COPD prevalence varied substantially between 19.8% (LLN-COPD) and 32.1% (GOLD-COPD). Twenty-three of 60 patients (38.3%) with GOLD-COPD were potentially misclassified as having COPD (FEV 1 /FVC   LLN). In contrast to patients with LLN-COPD, potentially misclassified patients did not differ significantly from those without COPD regarding respiratory symptoms and risk factors for COPD. Conclusions One fifth, rather than one third, of the patients with chronic HF had concomitant COPD using the LLN instead of the fixed ratio. LLN may identify clinically more important COPD than a fixed ratio of 0.7.