The forgotten message from gold: FVC is a primary clinical outcome measure of bronchodilator reversibility in COPD

BackgroundThe Global Initiative for Chronic Obstructive Lung Disease (GOLD) recommends the use of forced expiratory volume in 1 s (FEV1) to assess airways reversibility. The American Thoracic Society (ATS) and the European Respiratory Society (ERS) recommend FEV1 and/or forced vital capacity (FVC). This study assessed whether FVC detects reversibility in more chronic obstructive pulmonary disease (COPD) patients than FEV1 after acute short-acting bronchodilator inhalation.MethodsPlethysmographic data of 168 consecutive stable male COPD patients who underwent reversibility testing were analyzed.ResultsSeventy-seven patients showed a clinically significant increase in FVC, whereas only 49 patients showed a clinically significant increase in FEV1. Thus, FVC detected reversibility in 57% more patients than FEV1. Of the 90 patients showing clinically significant reversibility, FEV1 did not detect 41 patients that FVC detected, indicating a 45% difference.ConclusionFEV1 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.