Long-term exposure to outdoor air pollutants, especially ozone, accelerates the development of emphysema and age-related decline in lung function, even among people who have never smoked, according to a new study at Columbia. The findings may help explain why emphysema is relatively common in nonsmokers. Results are in the Journal of the American Medical Association.
Chronic lower respiratory disease is the fourth-leading cause of death in the U.S. and third-leading cause of death worldwide. Short-term exposure to air pollutants is a major risk factor for poor lung health. But the long-term effects of air pollutants on the lungs are not well understood.
The study, the largest and longest of its kind, looked at whether exposures to four major pollutants were associated with the development of emphysema and decline in lung function.
“The increase in emphysema was relatively large, similar to the lung damage caused by 29 pack-years of smoking and 3 years of aging,” said senior author Dr. R. Graham Barr, Hamilton Southworth Professor of Medicine and Epidemiology at Columbia Irving Medical Center and the Columbia University Mailman School of Public Health.
The study, co-led by the University of Washington, included more than 7,000 adults (ages 45 to 84) in Chicago, LA, Baltimore, St. Paul, NYC, and Winston-Salem, NC who were taking part in the MESA Air and MESA Lung studies. Participants were followed for a median of 10 years.
The researchers found that exposure to each of the pollutants at the beginning of the study was independently linked to the development of emphysema during the study period. The strongest association was seen with ozone. Only ozone, at baseline and during follow-up, was associated with a decline in lung function.Friday Letter Submission, Publish on August 23