Gastric cancer incidence trends in China: 1989-2018 registry data, 2022 Bayesian age-period-cohort estimates, ecological correlates
Abstract
Background
Gastric cancer is a major global public health challenge. Although previous studies have described incidence trends in limited populations, the relationship between long-term incidence trends and their driving factors remains unclear.
Aim
To investigate the temporal trends in gastric cancer incidence in China over three decades, identify key influencing factors, and assess changes in urban-rural disparities to inform prevention strategies.
Methods
This time-series correlation study used National Cancer Center data (1989-2018) with Bayesian age-period-cohort (BAPC)-model-projected incidence estimates for 2022. Joinpoint regression calculated annual percent change (APC) and average APC (AAPC) by gender and urban/rural residence. Bivariate correlation analysis examined associations between incidence and economic, environmental, and lifestyle factors.
Results
Gastric cancer incidence declined significantly across all groups: Rural males [AAPC: -3.47%; 95% confidence interval (CI): -4.19 to -2.74; P < 0.001]; urban males (AAPC, -1.51%; 95%CI: -2.68 to -0.33; P = 0.012); rural females (AAPC: -3.18%; 95%CI: -3.86 to -2.50; P < 0.001), and urban females (AAPC: -1.73%; 95%CI: -2.91 to -0.53; P = 0.005). Rural rates exceeded urban rates throughout, but the gap narrowed substantially by 2022. Strongest correlates of declining incidence included economic income (R 2, urban: 0.514; rural: 0.914); fresh food consumption (R 2, urban: 0.507; rural: 0.914); population migration (R 2, urban: 0.471; rural: 0.906); fresh fruit consumption (R 2, urban: 0.561; rural: 0.863); and industrial wastewater treatment (chemical oxygen demand R 2, urban: 0.253; rural: 0.766).
Conclusion
Thirty-year declining gastric cancer incidence in China showed ecological temporal correlations with economic development, environmental improvement, and dietary improvement. Rural areas demonstrated steeper declines but persistent disparities, highlighting priorities for targeted prevention.