PT  - JOURNAL ARTICLE
AU  - W. M. Vollmer
AU  - Þ. Gíslason
AU  - P. Burney
AU  - P. L. Enright
AU  - A. Gulsvik
AU  - A. Kocabas
AU  - A. S. Buist
TI  - Comparison of spirometry criteria for the diagnosis of COPD: results from the BOLD study
AID  - 10.1183/09031936.00164608
DP  - 2009 Sep 01
TA  - European Respiratory Journal
PG  - 588--597
VI  - 34
IP  - 3
4099  - http://erj.ersjournals.com/content/34/3/588.short
4100  - http://erj.ersjournals.com/content/34/3/588.full
SO  - Eur Respir J2009 Sep 01; 34
AB  - Published guidelines recommend spirometry to accurately diagnose chronic obstructive pulmonary disease (COPD). However, even spirometry-based COPD prevalence estimates can vary widely. We compared properties of several spirometry-based COPD definitions using data from the international Burden of Obstructive Lung Disease (BOLD)study. 14 sites recruited population-based samples of adults aged ≥40 yrs. Procedures included standardised questionnaires and post-bronchodilator spirometry. 10,001 individuals provided usable data. Use of the lower limit of normal (LLN) forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) ratio reduced the age-related increases in COPD prevalence that are seen among healthy never-smokers when using the fixed ratio criterion (FEV1/FVC <0.7) recommended by the Global Initiative for Chronic Obstructive Lung Disease. The added requirement of an FEV1 either <80% predicted or below the LLN further reduced age-related increases and also led to the least site-to-site variability in prevalence estimates after adjusting for potential confounders. Use of the FEV1/FEV6 ratio in place of the FEV1/FVC yielded similar prevalence estimates. Use of the FEV1/FVC<LLN criterion instead of the FEV1/FVC <0.7 should minimise known age biases and better reflect clinically significant irreversible airflow limitation. Our study also supports the use of the FEV1/FEV6 as a practical substitute for the FEV1/FVC.