Margit Pelkonen

The importance of physical activity for health is well recognized, but little is known about the influence of physical activity on pulmonary function. We have examined whether physical activity could slow down the decline in pulmonary function among the southwestern rural Finnish cohort of the Seven Countries Study. Physical activity was estimated by kilometers walked, cycled, and skied daily. We had complete data for 429 men for 10 years, 275 men for 20 years, and 186 men for 25 years. During the first 10 years, the decline in FEV was 9.8 ml/year less among men in the highest tertile of baseline physical activity than in men in the lowest tertile. According to the mean physical activity over either 20 or 25 years, men in the highest tertile also lost less pulmonary function (p = 0.009 and p = 0.043, respectively). A similar beneficial effect was observed in all smoking categories. In mortality analysis, continued high physical activity and an increase in activity to high level were associated with lower mortality. In conclusion, results indicated that physical activity is associated with a slower decline in pulmonary function and with lower mortality, and thus, middle-aged and older people should be encouraged to enjoy exercise.

BACKGROUND Permanent smoking cessation reduces loss of pulmonary function. Less is known in the long term about individuals who give up smoking temporarily or quitters with lower initial pulmonary function. Little is known also about the relationship between decline in pulmonary function and mortality. We examined these aspects and the association between smoking, decline in pulmonary function, and mortality. METHODS Two middle aged male Finnish cohorts of the Seven Countries Study and their re-examinations on five occasions during a 30 year period of follow up were analysed. RESULTS During the first 15 years (n=1007) adjusted decline in forced expiratory volume in 0.75 seconds (FEV_0.75) was 46.4 ml/year in never smokers, 49.3 ml/year in past smokers, 55.5 ml/year in permanent quitters, 55.5 ml/year in intermittent quitters, and 66.0 ml/year in continuous smokers (p0.75 had a slower decline in FEV_0.75 than continuous smokers. Among both continuing smokers and never smokers, non-survivors had a significantly (p0.75 than survivors. The adjusted relative hazard for total mortality was 1.73 (95% confidence interval (CI) 1.41 to 2.11) and 1.24 (95% CI 1.02 to 1.52) in the lowest and middle tertiles of decline in FEV_0.75. Never smokers, past smokers, and quitters had significantly lower total mortality than continuous smokers, partly because of their slower decline in FEV_0.75. CONCLUSION These results highlight the positive effect of smoking cessation, even intermittent cessation, on decline in pulmonary function. Accelerated decline in pulmonary function was found to be a risk factor for total mortality. The beneficial effect of smoking cessation on mortality may partly be mediated through a reduced decline in pulmonary function.

BACKGROUND Although it is well known that impaired pulmonary function is a strong predictor of mortality and that smoking decreases pulmonary function, little is known about the long term effect of smoking cessation on mortality at different levels of pulmonary function. We have studied the impact of smoking cessation on mortality over the entire range of baseline pulmonary function. METHODS The study subjects consisted of men aged 40–59 at entry who were the Finnish participants in the Seven Countries Study during 1959–89. RESULTS In all the participants (n = 1582) impaired forced expiratory volume in 0.75 seconds (FEV_0.75) was significantly associated with increased all cause mortality. When those who gave up smoking during the follow up period were compared with continuous smokers (n = 860) all cause mortality was found to be decreased among those who quit. The relative adjusted hazard (HR) was 0.71 (95% confidence interval 0.50 to 1.00). The median survival time in those who stopped smoking compared with those who continued to smoke from 1969 onwards was 7.65, 7.59, and 6.30 years longer in the lowest, middle and highest tertiles of adjusted FEV_0.75 distribution, respectively. In those who gave up smoking, mortality from cardiovascular causes was significantly lower (HR 0.60 (95% CI 0.37 to 0.98)). CONCLUSIONS These findings suggest that smokers across the entire range of pulmonary function may increase their expectation of lifespan by giving up smoking.