Smoking cessation slows loss of lung function. (Compared to Continuing Smokers).

Those who have kicked the smoking habit lose lung function at a significantly slower rate than those who keep smoking, reported Dr. Nicholas R. Anthonisen of the University of Manitoba, Winnipeg, and his colleagues in the Lung Health Study Research Group.

The findings come from a follow-up to a Lung Health Study performed 11 years previously Participants were randomly assigned to receive either smoking intervention or usual care and were classified into three groups based on smoking history: those who had quit, those who smoked intermittently and those who continued to smoke (Am. J. Respir. Grit. Care Med. 166[5]:675-79, 2002).

On follow-up, 4,145 participants from the original study had spirometry testing. For both smoking intervention (SI) and usual care (UC) participants, sustained quitters had the lowest rates of declining lung function. In the SI group, sustained quitters lost 0.23% of the predicted normal value for forced expiratory volume in 1 second ([FEV.sub.1]) Sustained quitters in the UC group lost 0.40% of the predicted normal value for [FEV.sub.1].

In contrast, continuing smokers in both groups had lost significantly more lung function. Continuing smokers in the SI ...