High‐resolution computed tomography in healthy smokers and never‐smokers: a 6‐year follow‐up study of men born in 1933

Purpose: To elucidate whether emphysematous lesions and other high‐resolution computed tomography (HRCT) findings considered associated with smoking are part of a progressive process, and to measure the extent to which similar changes are found in never‐smokers. Material and Methods: Healthy smokers and never‐smokers were recruited from a randomized epidemiological study and investigated with a 6‐year interval. Emphysema, parenchymal and subpleural nodules, ground‐glass opacities, bronchial alterations, and septal lines were evaluated in 66 subjects (40 smokers, 11 of whom had stopped smoking in the interval, and 26 never‐smokers). Lung function was tested. Results: All except emphysematous lesions were present to some extent in never‐smokers. Emphysema, parenchymal nodules, and septal lines occurred significantly more in current smokers, and a progression in extent of emphysema, ground‐glass opacities, bronchial alterations and septal lines was seen. There was no significant change among those who stopped and never‐smokers except for bronchial alterations, which progressed in never‐smokers. Conclusion: In healthy, elderly never‐smokers a low extent of various HRCT findings has to be considered normal. Emphysema, parenchymal nodules, and ground‐glass opacities are indicative of smoking‐induced disease. Further progress may cease if smoking is stopped.