[Smoking cessation in patients with severe irreversible chronic obstructive pulmonary disease, "smoker's lung"]

A one year prospectively recorded material of 80 patients with severe chronic obstructive pulmonary disease (COPD) (FEV-1 < 40% predicted), only one never smoker and 26 ex-smokers, were included in the study. The 53 smokers were offered a smoking cessation program. Fifty-three of the total were alive after one year, including 16 of the ex-smokers. Twenty-one (57%) of the 37 surviving smokers had quit smoking (carbon monooxide in expired air < 10 ppm), whereas 16 (43%) still were smoking. FEV-1 increased by median 100 ml among both the quitters (p < 0.01), and the ex-smokers (p < 0.02), whereas FEV-1 declined by 50 ml (p > 0.05) among those who continued to smoke. There were more deaths among the sustainers than among the quitters (p < 0.05). Taking into consideration the many sources of bias in this small, uncontrolled study it seems as if smoking cessation prevents loss of lung function and perhaps even death among patients with advanced degree of smoker's lung.