Despite the culture war on smokers, the idea that cigarette smoking causes lung cancer or lung disease is largely a myth.   Anti-smoking groups are a multi-billion dollar industry on their own and continued marketing is a key part of maintaining the revenue stream but only 10% of smokers get lung cancer and 50% of lung cancer victims never smoked.

However, cigarette smoking is obviously not good for you so you shouldn't do it, and work continues to determine how smoking impacts risk factors for diseases.

Given that smoking has been in the news for so long, it may surprise you to learn that only recently a team of researchers at Brigham and Women’s Hospital (BWH) determined that approximately one out of every twelve adult smokers have abnormal lung densities present on chest computed tomography (CT) images, which are suggestive of interstitial lung disease which is associated with substantial reductions in lung volumes.

But these lung densities were inversely not associated with emphysema, despite being positively associated with smoking for decades.

Interstitial lung disease may evolve prior to the development of symptoms. Although it is known that smoking can cause some forms of interstitial lung disease, the prevalence of these chest CT scan abnormalities and their effect on lung volumes had been unclear. “This manuscript highlights the degree of lung volume reduction associated to previously unrecognized interstitial lung abnormalities in smokers,” said Hiroto Hatabu, MD, and Ivan Rosas, MD of the Divisions of Radiology and Pulmonary/Critical Care Medicine at BWH. 

In the New England Journal of Medicine study, researchers characterized the presence of interstitial lung abnormalities in 2416 participants from the COPDGene study. The researchers found that interstitial lung abnormalities are associated with both reduced total lung capacity and less emphysema in smokers. The team also found that smokers with interstitial lung abnormalities are at an increased risk for a restrictive reduced lung oxygen volume.lung deficit.

“The fact that smoking can result in distinct, and to some degree, physiologically divergent pulmonary conditions highlights the need for a better understanding of the phenotypic, environmental, and genetic backgrounds that can predispose smokers to diverse pulmonary diseases,” said George Washko, MD, and Gary Hunninghake, MD, of the Division of Pulmonary/Critical Care Medicine at BWH.

Further research is needed to definitely characterize the link between interstitial lung abnormalities present on chest CT and idiopathic pulmonary fibrosis, the most common and severe form of interstitial lung disease.