A comparison of the burden of lung cancer attributable to tobacco exposure in China and the USA.

BACKGROUND:Tobacco exposure (TE) is the major contributor to lung cancer mortality worldwide. This study aims to clarify the possible reasons underlying the long-term trends and differences in lung cancer mortality attributable to TE in China and the United States of America (USA). METHODS:Lung cancer mortality data from China and the USA were obtained from the Global Burden of Disease (GBD) Study 2017. Joinpoint regression analysis was used to assess the magnitude and direction of trends from 1990 to 2017, and the age-period-cohort model (APCM) was used to analyze the temporal trends of lung cancer mortality by age, period, and cohort. RESULTS:For lung cancer attributable to smoking, the age-standardized mortality rates (ASMRs) exhibited an upward trend in China and a downward trend in the USA. The overall net drifts per year were 0.72% for China and -3.03% for the USA, and the local drift values in China and the USA increased by age group. All cohort/period relative risks (RRs) increased in China but decreased in the USA. The longitudinal age curves increased rapidly in China, whereas those in the USA were rose gradually. For lung cancer attributable to secondhand smoke, the ASMRs showed a downward trend in both China and the USA. The overall net drifts per year were -0.48% for China and -3.97% for the USA, and the local drift values in China and the USA also increased by age group. Cohort/period RRs decreased in the USA, and fluctuated in China. The longitudinal age curve trends in China and the USA were similar to those of smoking. CONCLUSIONS:The dangers of TE in China remain serious. The rates of lung cancer mortality attributable to TE have increased, especially in older individuals. We recommend that China strengthens the implementation of effective targeted tobacco control policies and other interventions to reduce the burden of lung cancer.