Background:
In response to the Agency for Healthcare Research and Quality statement questioning the usefulness of “screening spirometry,” the National Heart, Lung, and Blood Institute and the COPD Foundation held a consensus conference in June 2008 to establish a procedure to detect cases of COPD in the general population. Conference participants developed a three-stage approach, using a brief questionnaire, peak flow measurement with a pocket spirometer, and diagnostic quality spirometry. The overall objective of this study was to examine the usefulness of a simple questionnaire and peak flow measurement in screening for COPD in a self-selected population. We hypothesized that this combination would efficiently screen for clinically relevant COPD.
Methods:
We queried individuals attending public events regarding the presence of wheeze and/or asthma, mucus production, dyspnea, exposure to irritants, and tobacco use. Peak expiratory flow (PEF) was then measured with a pocket spirometer. If PEF was < 70% predicted, spirometry was performed. In order to estimate the false-negative rate, a random sample of every 10th participant was also selected for spirometry.
Results:
Between June 2008 and December 2009, 5,761 adults completed the risk assessment questionnaire. The mean age of the respondents was 54 years, 58% were women, and 88% were white. Of these, 5,638 participants completed pocket spirometry, and 315 (5.6%) had PEF < 70% predicted. Of 5,323 with normal PEF, 651 underwent spirometry. The performance of PEF was assessed via positive and negative predictive values relative to a diagnosis of clinically significant airflow obstruction, defined as FEV1/FEV6 < the lower limit of normal and FEV1 < 60% predicted. Of 4,238 subjects with at least two risk factors, 267 (6.3%) had PEF < 70%, compared with 48 of the 1,400 subjects (3.4%) with fewer than two risk factors (P < .001). Based on 729 participants with acceptable spirometry, 63.1% (113 of 179) of those with abnormal PEF tested positive for clinically significant airflow obstruction, compared with 5.5% (30 of 550) with normal PEF (P < .001). The estimated prevalence of significant COPD among the 5,638 screened was 8.7%, and sensitivity and specificity were 40.7% and 97.7%, respectively.
Conclusions:
A staged approach to COPD screening in adults is useful for detecting clinically significant airflow obstruction in our study population.
From the American Association for Respiratory Care (Mr Nelson), Irving, TX; University of North Carolina (Drs LaVange and Nie), Chapel Hill, NC; COPD Foundation (Mr Walsh), Miami, FL; University of Arizona (Dr Enright), Tucson, AZ; University of Michigan (Dr Martinez), Ann Arbor, MI; University of Kentucky (Dr Mannino), Lexington, KY; Columbia University (Dr Thomashow), New York, NY.Correspondence to: Steven Nelson, MS, American Association for Respiratory Care, 9425 N MacArthur Blvd, Irving, TX 75063; e-mail: nelson@aarc.org
Author contributions: Mr Nelson had full access to the data and takes responsibility for the integrity and accuracy of the data.
Mr Nelson: contributed to the study concept and design, acquisition of data, preparation and critical revision of the manuscript, and final approval of the version to be published.
Dr LaVange: contributed to the study concept and design, statistical analysis, preparation and critical revision of the manuscript, and final approval of the version to be published.
Dr Nie: contributed to the statistical analysis, preparation and critical revision of the manuscript, and final approval of the version to be published.
Mr Walsh: contributed to the study concept and design and revision of the manuscript.
Dr Enright: contributed to the study concept and design, acquisition of data, drafting of the article, preparation and critical revision of the manuscript, and final approval of the version to be published.
Dr Martinez: contributed to the study concept and design, preparation and critical revision of the manuscript, and final approval of the version to be published.
Dr Mannino: contributed to the study concept and design, preparation and critical revision of the manuscript, and final approval of the version to be published.
Dr Thomashow: contributed to the study concept and design as the principal investigator, analysis and interpretation of data, preparation and critical revision of the manuscript, and final approval of the version to be published.
Financial/nonfinancial disclosures: The authors have reported to CHEST the following conflicts of interest: Mr Nelson is an employee of the American Association for Respiratory Care and a member of the Medical and Scientific Advisory Board of the COPD Foundation. Dr LaVange previously owned stock options in Inspire Pharmaceuticals. She served on data and safety monitoring boards for several pharmaceutical companies in the past 3 years, namely MAP Pharmaceuticals; Merck & Co, Inc; and GlaxoSmithKline. Her role was to review data from ongoing clinical trials and evaluate whether the patients’ safety was at risk. Mr Walsh is president and a member of the board of directors of the COPD Foundation. Dr Enright is a member of the Medical and Scientific Advisory Board of the COPD Foundation. Dr Martinez has participated in advisory boards in COPD development for Actelion Pharmaceuticals Ltd; Almirall; American Institutes for Research; AstraZeneca; Bayer; BoomComm; Center for Health Care Education; Forest Laboratories, Inc; GlaxoSmithKline; Ikaria; MedImmune, LLC; Merck & Co, Inc; Novartis AG; Nycomed; Pearl; Pfizer, Inc; and Schering. He has been a member of steering committee for COPD studies sponsored by Actelion Pharmaceuticals Ltd; GlaxoSmithKline; Forest Laboratories, Inc; MPex; and Nycomed. He has participated in Food and Drug Administration mock panels for Boehringer Ingelheim GmbH and Forest Laboratories, Inc. The University of Michigan received funds from Boehringer Ingelheim GmbH for a COPD study. Dr Martinez has served on speaker’s bureaus or in continuing medical education activities sponsored by American College of Chest Physicians; American Lung Association; Almirall; AstraZeneca; Beaumont; Boehringer Ingelheim GmbH; CME Incite; ePocrates; Forest Laboratories, Inc; France Foundation; GlaxoSmithKline; Lovelace; MedEd; NACE; Nycomed; Potomac; Prescott; Sanofi-Aventis; St. Luke’s; and UpToDate. He has received royalties from Associates in Medical Marketing, Castle Connolly. Dr Mannino is a member of the medical and scientific advisory board and the board of directors of the COPD Foundation. He has served on advisory boards for Boehringer Ingelheim GmbH; Pfizer, Inc; GlaxoSmithKline; Sepracor (now Sunovion Pharmaceuticals, Inc); AstraZeneca; Novartis AG; and Ortho Biotech and has received research grants from AstraZeneca, GlaxoSmithKline, Novartis AG, and Pfizer, Inc. Dr Thomashow is a member of the medical and scientific advisory board and chairman of the board of directors of the COPD Foundation. He has served on advisory boards for GlaxoSmithKline, Boehringer Ingelheim GmbH, Talecris, Intermune, and Forest Laboratories, Inc. Dr Nie has reported that no potential conflicts of interest exist with any companies/organizations whose products or services may be discussed in this article.
Role of sponsors: The COPD Foundation provided the entire funding for this study, including payment of all expenses, both direct and indirect, for the COPD Foundation Mobile Spirometry Unit at venues selected by the study steering committee. The American Association for Respiratory Care (AARC) provided in kind support of senior staff participation, and study project management.
Additional information: The e-Appendixes and e-Table can be found in the “Supplemental Materials” area of the online article.
Funding/Support: The COPD Foundation provided funding for the performance of the study.Reproduction of this article is prohibited without written permission from the American College of Chest Physicians. See online for more details.