Doctors could soon have a new tool to help diagnose chronic obstructive pulmonary disease (COPD).
A questionnaire called CAPTURE successfully identified almost half of clinical trial participants who had moderate to severe forms of previously undiagnosed COPD, researchers report.
"The goal with trying to find COPD is to treat it earlier, which will help make patients feel better and hopefully prevent their disease from progressing," said principal investigator Dr. Fernando Martinez, chief of the pulmonary and critical care medicine division at Weill Cornell Medicine in New York City.
More than 15 million Americans have been diagnosed with COPD, and experts think millions more have it but don't know it. COPD is a leading cause of death in the United States.
Common COPD symptoms include coughing, shortness of breath, wheezing or whistling in the chest, and tightness or heaviness of the chest.
The CAPTURE tool asks patients to answer five questions that assess their breathing and exposure to chemicals or air pollution.
Those with medium scores take an in-office breathing test to gauge the force of their exhalation, a sign of lung function.
People who score low on that test — or who scored high on the CAPTURE questionnaire — proceed to a spirometry breathing test, which is considered the gold standard for diagnosing COPD.
CAPTURE screening gives doctors additional information to assess patients with respiratory symptoms, the study authors said.
Only about one-third of COPD assessments include spirometry, because the tests can be difficult to integrate into a short visit with a primary care doctor.
"CAPTURE was designed to be easy for physicians to use. The screening is simple, takes less than a minute, and helps identify adults with trouble breathing who should be evaluated further," Dr. Antonello Punturieri, program director of the U.S. National Heart, Lung, and Blood Institute's Chronic Obstructive Pulmonary Disease/Environment Program, said in an institute news release.
CAPTURE's clinical trial involved more than 4,300 adults aged 45 to 80, and ran from October 2018 to April 2022.
By the end, about 2.5% of the study sample had been diagnosed with moderate to severe forms of COPD. Of those cases, CAPTURE accurately identified about 48% as having COPD.
The researchers estimated that 1 in 81 CAPTURE screenings would identify an adult with treatable but previously undiagnosed COPD, based on these results.
However, CAPTURE also gave a false positive result for 479 participants who did not have COPD.
The researchers said they are studying ways to improve the tool's accuracy through minor changes like altering questions or adding others. But they emphasized that the goal is to identify people who would benefit from COPD testing with spirometry.
The findings were published Feb. 14 in the Journal of the American Medical Association.
"The study shows that there is a high degree of respiratory burden in primary care, and physicians need to ask about it and do the appropriate testing to determine if symptoms are driven by COPD or another process so that patients can get the right treatment," said principal investigator Dr. MeiLan Han, a professor of medicine in the division of pulmonary and critical care at the University of Michigan, in Ann Arbor.
Larger studies are underway to further assess CAPTURE and how doctors use the tool in practice. Results are expected later this year.