Treating mucus plugs in COPD could affect mortality

Targeting mucus plugs could lower mortality from COPD, chronic obstructive pulmonary disease, the fourth leading cause of death in the United States.

Researchers reported this finding on May 21, 2023 in JAMA, the Journal of the American Medical Association. The findings were also reported on the same day at the American Thoracic Society 2023 International Conference.

“As a chronic disease, COPD can’t be cured, but our findings suggest that using therapies to break up these mucus plugs could help improve outcomes for COPD patients, which is the next best thing,” said author Alejandro Diaz, MD, associate scientist in the Division of Pulmonary and Critical Care Medicine at Brigham and Women’s Hospital in Boston and assistant professor of medicine at Harvard Medical School.

The new study is a retrospective analysis of data from the Genetic Epidemiology of COPD (COPDGene) study, which investigated the underlying genetic risk factors of COPD.

COPDGene subjects were enrolled between November 2007 and April 2011, and they were followed through August 31, 2022. The study included subjects with COPD at different stages, from the mildest to the most severe.

The researchers in the new study analyzed chest CT scans from 4,363 COPDGene subjects taken at their first visit to the clinic. This enabled the researchers to find mucus plugs even in those who did not feel sick.

The researchers reported that the mortality rate over the course of the study for subjects with no detectable mucus plugs was 34 percent. For those with mucus plugs in up to two lung segments, the mortality rate rose to 46.7 percent. For those with plugs in three or more lung segments, the mortality rate was 54.1 percent.

“The fact that these mucus plugs were associated with mortality across different disease phases tells us that there are aspects of COPD progression that can be picked up by a CT scan even if they’re not felt by the patient,” said Diaz.

Since mucus is a therapeutic target for other diseases, the investigators plan to test existing mucus-targeting therapies in people with COPD.

“For the last four decades we’ve had only two targets for COPD therapies –either promoting bronchial dilation, which means making the airways themselves wider, or reducing bronchial inflammation,” said Diaz. “This is telling us that there may be more we can do about this disease than we realized before….Mucus is something that we already know a lot about from a basic science standpoint, and there are also a lot of mucus-targeting therapies that either already exist or are in development for other diseases, so it’s an extremely promising target.”