Analysis of long-term trends and 15-year predictions of smoking-related bladder cancer burden in china across different age and sex groups from 1990 to 2021.

BACKGROUND

Tobacco is a significant risk factor for bladder cancer, with notable disparities in smoking rates and cancer prevalence between sex. Our objective is to assess the sex- and age-specific burden of bladder cancer attributable to smoking in China from 1990 to 2021, and predict its future trends over the next 15 years using GBD study data.

METHODS

All data were extracted from the 2021 GBD study, utilizing metrics such as mortality rates, disability-adjusted life years (DALYs), age-standardized mortality rates (ASMR), and age-standardized DALY rates (ASDR) to describe the burden of smoking-attributable bladder cancer in China. We employed joinpoint and age-period-cohort (APC) analysis methods to elucidate the epidemiological characteristics of bladder cancer. Frontier analysis was used to visually demonstrate the potential for burden reduction based on the development level of each country or region. We applied the ARIMA model to fit and predict the future burden of smoking-attributable bladder cancer in China for the next 15 years.

RESULTS

From 1990 to 2021, the number of deaths and DALYs due to smoking-attributable bladder cancer in China significantly increased. However, ASMR and ASDR decreased for both sexs but males experiencing a higher burden. Population aging drove the decline in ASMR and ASDR, despite rising absolute deaths and DALYs. Joinpoint regression yielded average annual percentage changes (AAPC) of - 1.23 for ASMR and - 1.38 for ASDR, with the rate of change being lower in males than in females. The impact of age, period, and cohort on mortality rates varied. There was a slight increase in relative health inequality in the bladder cancer burden among countries of different income levels. By 2036, ASDR and ASMR for smoking-related bladder cancer in China are expected to continue decreasing, with this trend being more pronounced in males.

CONCLUSION

Over the past three decades, the number of deaths and DALYs due to smoking-related bladder cancer in China has significantly increased across different sexs and age groups, while ASMR and ASDR have shown a declining trend, reflecting certain public health progress. This trend is especially evident among males and is primarily driven by population aging and demographic effects. The inequality among countries of different income levels has slightly increased. The burden of smoking-related bladder cancer in China is projected to continue declining by 2036, particularly among males. Therefore, precise prevention and intervention strategies targeting different sexs and age groups are essential to further alleviate the public health burden of smoking-related bladder cancer.