Can a Single Spirometry Measure Accurately Diagnose Chronic Obstructive Pulmonary Disease?

In patients with typical respiratory symptoms and histories of exposure to inhaled toxins, chronic pulmonary obstructive disease (COPD) is diagnosed by confirming fixed airflow obstruction on spirometry (i.e., post-bronchodilator forced expiratory volume in 1 second [FEV₁] to forced vital capacity [FVC] ratio of <0.70). After a patient is labeled as having COPD, this diagnosis often is not revisited. In this study, researchers used data from serial spirometry in more than 7000 patients with mild-to-moderate COPD in two prospective cohort studies to evaluate changes in airflow obstruction over time.

During 5 years, 13% and 27% of patients in the two studies no longer met criteria for fixed obstruction and thus no longer had COPD (diagnostic r…