10-year imaging study examines long-term side effects of smoking cigarettes
Results from a 10-year study on the progression of emphysema in smokers offer new insights into the long-term ramifications of cigarette smoking.
Published in Radiology on April 11, the research highlights serious pulmonary consequences that face individuals with chronic obstructive pulmonary disease (COPD) who fail to quit smoking. Compared to former smokers with trace emphysema at baseline imaging, current smokers displayed a significant decline in adjusted lung density (ALD) on imaging over a 10-year period, even after adjusting for multiple patient and scanning factors. Researchers also noted that emphysema progression occurred faster in continuous smokers than in former smokers.
Experts involved in the study suggested that their findings support the notion that it really is never too late to quit smoking, as the benefits of doing so are clear.
“This difference in the rate of emphysema progression provides further support for smoking cessation even in individuals with established emphysema,” corresponding author of the new paper David Baraghoshi, from the Division of Biostatistics, Environment and Health at Jewish National Health in Denver, Colorado, and colleagues noted.
A total of 8,431 current and former smokers from the COPDGene study were included in the analysis. Participants were prospectively followed for 10 years, undergoing CT imaging at baseline and then again at five- and 10-year follow-up.
Of the 8,431 participants, 49% were current smokers and 53% had more than trace emphysema on baseline imaging. These individuals weathered the greatest decline in ALD, with annual decreases of 1.4 g/L in the first five years and 0.9 g/L in the second five years. Former smokers had the lowest average ALD at each imaging interval and their trajectory of lung density loss was less than that of current smokers.
Although other studies have assessed the long-term lung damage caused by smoking cigarettes, this latest research stands out for a couple of different reasons, the authors suggested.
First, the team adjusted their estimates based on different CT equipment and individual protocols used for the scans—something that has not been studied extensively in prior research. Second, 10 years' worth of data was included in the study, allowing the team to better understand the long-term progression of emphysema in both smokers and nonsmokers.
To study abstract is available here, and an accompanying editorial can be found here.