Background: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommends the use of forced expiratory volume in 1s (FEV(1)) to assess airways reversibility. The American Thoracic Society (ATS) and the European Respiratory Society (ERS) recommend FEV(1) and/or forced vital capacity (FVC). This study assessed whether FVC detects reversibility in more chronic obstructive pulmonary disease (COPD) patients than FEV(1) after acute short-acting bronchodilator inhalation.
Methods: Plethysmographic data of 168 consecutive stable male COPD patients who underwent reversibility testing were analyzed.
Results: Seventy-seven patients showed a clinically significant increase in FVC, whereas only 49 patients showed a clinically significant increase in FEV(1). Thus, FVC detected reversibility in 57% more patients than FEV(1). Of the 90 patients showing clinically significant reversibility, FEV(1) did not detect 41 patients that FVC detected, indicating a 45% difference.
Conclusion: FEV(1) underestimates acute bronchodilation effects. FVC should thus be a primary clinical outcome measure of bronchodilator reversibility in COPD, as it detects reversibility in more patients. This message, forgotten by GOLD, should be promoted in future consensus statements.