Smoking and Subclinical Interstitial Lung Disease

The relationships between cigarette smoking and heart disease, lung cancer, and chronic obstructive pulmonary disease (COPD) are well known; in contrast, the topic of the relationship between smoking and interstitial lung disease is almost obscure. Despite its lack of a public persona, this relationship is important, since smoking plays a key role in the pathobiology of several interstitial lung diseases — respiratory bronchiolitis, desquamative interstitial pneumonia, pulmonary Langerhans'-cell histiocytosis, and perhaps idiopathic pulmonary fibrosis.1 It is widely known that in asymptomatic smokers with normal lung function, chest radiography reveals the presence of interstitial opacities (also known as dirty lung).2 The . . .