EFFECTS OF CIGARETTE-SMOKING ON LUNG-FUNCTION IN 4 POPULATION SAMPLESIN THE PEOPLES-REPUBLIC-OF-CHINA

As part of an ongoing study of cardiopulmonary risk factors in the Peo ple's Republic of China, we conducted lung function tests and obtained information about smoking habits on 6,765 Chinese men and women 35 to 56 yr of age residing in or around Beijing in the north and in or aro und Guangzhou in the south. Within each region, separate urban and rur al populations were recruited. This study examined the relationship be tween tobacco consumption (both manufactured cigarettes and leaf tobac co) and lung function in a subset of current smokers and never smokers who had acceptable lung function data. All methods were strictly stan dardized. Overall, tobacco smoking was associated with a statistically significant mean difference in FEV(1) among men (-89 ml) and women (- 52 ml) relative to never smokers after adjusting for age, height, and residence. Differences between smokers of cigarettes and smokers of le af tobacco were not significant. Among the subset of smokers who smoke d only cigarettes, this decrement increased with increasing duration o f cigarette smoking, but it was small (-4 ml/yr of smoking for FEV(1) for both men and women) in comparison with the effects of smoking repo rted from western countries. Although the smoking effect tended to inc rease with increasing dose, these differences were small and generally not statistically significant. The relatively small smoking effect in this study may result from differences between developed and developi ng countries in the cumulative dose of tobacco products. Alternative e xplanations or contributing factors such as racial differences in susc eptibility and differences in the form and delivery of tobacco cannot be discounted.