Abstract: Objective The Objective of this study was to analyze the long-term change trend of gastric cancer incidence in China from 1990 to 2021,and to provide scientific suggestion for the prevention and control of gastric cancer in China. Methods The incidence burden data of gastric cancer from 1990 to 2021 were obtained from the Global Burden of Disease(GBD)2021 database.The age-period-cohort model was to evaluate its independent effects,and the Nordpred model was used to predict its incidence trend from 2022 to 2031. Results The number and incidence of gastric cancer from 1990 to 2021 in China showed an upward trend,while the age-standardized incidence showed a decreasing trend.The results of age-period-cohort model showed that in the same birth cohort,the incidence of gastric cancer in China increased with age,the incidence of the total population increases from 0.91/100,000 to 233.37/100,000 in total population,the incidence of men increases from 0.91/100,000 to 508.90/100,000,and the incidence of women increases from 1.04/100,000 to 115.86/100,000.During the period from 1992—1996 to 2017—2021,the relative risk(RR)of gastric cancer incidence showed a decreasing trend with the passage of time.The RR of the total population period decreased from 1.10 to 0.72,with males decreasing from 1.06 to 0.75 and females decreasing from 1.19 to 0.65.The later the birth cohort throughout the birth cohort years,the lower the risk of onset;The RR of gastric cancer incidence in the total population decreased from 1.60 to 0.34,from 1.36 to 0.40 for males and from 2.23 to 0.22 for females.The incidence prediction results showed that by 2031,the incidence of gastric cancer would increase to 470,429 cases,including 323,399 cases for men and 147,029 cases for women.The standardized incidence of the total population would decrease to 23.80/100,000 cases,35.13/100,000 cases for men and 24.17/100,000 cases for women. Conclusion The prevention and treatment measures of gastric cancer from 1990 to 2021 have achieved certain results in reducing the risk of gastric cancer,but the incidence of gastric cancer is still serious,and it is necessary to focus on strengthening the intervention for men over 50 years old.

Key words: Stomach cancer, Incidence rate, Age-period-cohort model, Prediction