Table 1.
Smokers with normal spirometry | COPD GOLD stage I | GOLD Unclassified | COPD GOLD stage II+ | |
---|---|---|---|---|
Postbronchodilator FEV1/FVC ratioa | ≥0.70 | <0.70 | ≥0.70 | <0.70 |
Postbronchodilator FEV1 percent predicteda | ≥80 % | ≥80 % | <80 % | <80 % |
Abbreviations: COPD Chronic Obstructive Pulmonary Disease, FEV 1 forced expiratory volume in one second, FVC forced vital capacity, GOLD Global Initiative for Chronic Obstructive Lung Disease
aPostbronchodilator FEV1/FVC ratio was based on the GOLD criteria [4] and percent predicted FEV1 value was defined by the third National Health and Nutrition Examination Survey or NHANES-III reference equations [15])