The influence of cigarette smoking and its withdrawal on the annual change of lung function in pulmonary emphysema.

Fifty-six male patients with pulmonary emphysema were followed for a minimum period of three years (range 3-13), to observe the effects of smoking and smoking withdrawal. The subjects were divided into smokers (Group S) and ex-smokers (Group EX-S). Forced expiratory volume in one second (FEV1) and vital capacity (VC) declined at a significantly (p less than 0.001) faster rate in those who continued to smoke than in ex-smokers. No significant difference between the two groups was observed for kCO (permeability coefficient) and PaO2 (arterial oxygen tension). There was a significant (p less than 0.001) difference between the two groups in the annual change in body weight. We conclude that all patients with emphysema, even those with advanced disease, should be encouraged to stop smoking.