Trends in colorectal cancer mortality in China from 2004 to 2021: an epidemiological analysis based on national disease surveillance data

Background: Colorectal cancer (CRC) is a common malignant tumor in the digestive system worldwide. In China, there are significant challenges in prevention and control, and there is a lack of relevant evidence regarding the long-term epidemiological trends. This study aims to evaluate the CRC mortality data in China from 2004 to 2021 and to explore the trends of age-specific and stratified mortality rates by age, gender, urban-rural areas, and regions. Method: The CRC mortality data from 2004 to 2021 were extracted from the China Disease Surveillance Point (DSP) system. After excluding low-quality data, the mortality rates for five age groups, gender, urban-rural residence, and regions were calculated. Independent sample t-tests and 95% confidence intervals (CI) were used to compare differences between groups and the average mortality rates before and after 2012. The long-term trend was analyzed using the age-period-cohort (APC) model and the analysis was conducted using R 3.1.2 and SAS 9.4. Result: The standardized CRC mortality rate for Chinese adults was 11.5 per 100,000 (95% CI: 11.3 - 11.7), showing a significant age gradient. The mortality rate for men (14.2 per 100,000) was higher than that for women (9.1 per 100,000), and the mortality rate in urban areas (14.1 per 100,000) was higher than that in rural areas (10.0 per 100,000). The overall mortality rate remained stable (average annual change rate -0.10%), but the mortality rate for people aged 65 and above significantly increased, especially for those aged 85 and above (average annual change rate 2.52%, 95% CI: 0.98 - 4.09). The mortality rate increase for men aged 85 and above in the western rural areas was the most significant (average annual change rate 5.53%, 95% CI: 3.14 - 7.97). Conclusion: The mortality rate of CRC in China shows significant differences among populations and regions. The burden is particularly heavy for men, urban residents, and people in the eastern coastal areas. Strengthening early screening for high-risk groups and optimizing the allocation of regional medical resources are crucial for reducing the burden of CRC.