COPD Screening Events Contribute Data for Study in CHEST

August 21, 2012

The AARC’s active involvement in screening the general public for COPD via health care expos and other events has now paid off in the publication of a study in the August issue of CHEST.

The paper, which was co-authored by AARC Associate Executive Director in Charge of IT Operations Steve Nelson, MS, RRT, FAARC, along with Lisa M. LaVange, PhD; Yonghong Nie, PhD; John W. Walsh; Paul L. Enright, MD; Fernando J. Martinez, MD, FCCP; David M. Mannino, MD, FCCP; and Byron M. Thomashow, MD, FCCP, finds a staged approach to screening can detect clinically significant airflow obstruction.

The research grew out of an Agency for Healthcare Research and Quality statement questioning the usefulness of screening spirometry in healthy adults who are not reporting symptoms.

That statement spurred a consensus conference on the topic hosted by the National Heart, Lung and Blood Institute and the COPD Foundation. A three staged approach to screening consisting of a brief questionnaire, peak flow measurement with a pocket spirometer, and diagnostic quality spirometry was developed by conference participants.

In their study, Nelson and his colleagues used this approach to screen adults, most of them participants in the health screening events supported by the AARC and its members. Overall, 5,638 people completed pocket spirometry. Among that group, 5.6% were identified with PEF <70% predicted and sent for spirometry. Spirometry was performed by respiratory therapists with pulmonary function testing experience.

Results showed:

• Based on 729 participants with acceptable spirometry, 63.1% of those with abnormal PEF tested positive for clinically significant airflow obstruction, compared to 5.5% with normal PEF.
• The estimated prevalence of significant COPD was 8.7%, and sensitivity and specificity were 40.7% and 97.7%, respectively.

With such a high specificity of PEF to clinically significant reduced airflow by spirometry, it can be concluded that PEF is a useful tool in detecting people at risk for COPD. Nelson and his colleagues further conclude, “Using a pocket spirometer in a screening program can reduce the number of diagnostic spirometry tests required. A step-wise approach to detect undiagnosed people with clinically significant airflow obstruction can reduce costs and increase accuracy.”

They believe this approach could increase the ease of finding previously undiagnosed COPD at an earlier stage in asymptomatic patients and also improve the care of COPD patients in clinical practice.