Smoking-related emphysema is associated with idiopathic pulmonary fibrosis and rheumatoid lung.

Background And Objective: A combined pulmonary fibrosis/emphysema syndrome has been proposed, but the basis for this syndrome is currently uncertain. The aim was to evaluate the prevalence of emphysema in idiopathic pulmonary fibrosis (IPF) and rheumatoid lung (rheumatoid arthritis-interstitial lung disease (RA-ILD)), and to compare the morphological features of lung fibrosis between smokers and non-smokers.

Methods: Using high-resolution computed tomography, the prevalence of emphysema and the pack-year smoking histories associated with emphysema were compared between current/ex-smokers with IPF (n = 186) or RA-ILD (n = 46), and non-chronic obstructive pulmonary disease (COPD) controls (n = 103) and COPD controls (n = 34).