Instability in the COPD Diagnosis upon Repeat Testing Vary with the Definition of COPD

BackgroundA low FEV1/FVC from post-bronchodilator spirometry is required to diagnose COPD. Both the FEV1 and the FVC can vary over time; therefore, individuals can be given a diagnosis of mild COPD at one visit, but have normal spirometry during the next appointment, even without an intervention.MethodsWe analyzed two population-based surveys of adults with spirometry carried out for the same individuals 5-9 years after their baseline examination. We determined the factors associated with a change in the spirometry interpretation from one exam to the next utilizing different criteria commonly used to diagnose COPD.ResultsThe rate of an inconsistent diagnosis of mild COPD was 11.7% using FEV1/FVC 1/FEV6 1.ConclusionsUsing FEV1/FEV6