Context: The few published prospective studies of smoking and mortality in China have reported low relative risks, but the durations of follow-up were short.
Objective: To assess the mortality of ever- and never-smokers in a cohort after 20 years of follow-up.
Design, setting, and subjects: A cohort analytic study in a machinery factory in Xi'an, China, involving 1696 people aged 35 years or older (1124 men and 572 women) examined in May 1976.
Main outcome measures: All-cause and tobacco-associated mortality.
Results: A total of 56% of the men and 12% of the women were ever-smokers at baseline. Through August 31, 1996, 218 persons (173 men and 45 women) had died. The relative risks (95% confidence intervals [CIs]) for ever smoking (after adjusting for age, marital status, occupation, education, diastolic blood pressure, and triglyceride and cholesterol levels) for deaths resulting from all causes, all cancer, and coronary heart disease were, respectively, 2.42 (95% CI, 1.72-3.42), 2.50 (95% CI, 1.41-4.43), and 3.61 (95% CI, 1.35-9.67) in men and 2.32 (95% CI, 1.18-4.56), 1.98 (95% CI, 0.50-7.92), and 4.67 (95% CI, 0.78-27.8) in women.
Conclusions: Previous prospective studies of smoking-related mortality in China tended to underestimate the risks, probably because of short durations of follow-up. We have demonstrated that smoking is a major cause of death in China, and the risks are similar to those seen in the United States and the United Kingdom. Thus, about half of the 300 million smokers in China will eventually die of smoking-related diseases if urgent tobacco-control measures are not instituted to prevent this growing epidemic.