Abstract
BACKGROUND: This study evaluated the burden of breast cancer (BC) in Belt and Road Initiative (BRI) countries from 1990 to 2021 by age, sex, and risk factors, aiming to guide health promotion. METHODS: Data from 66 BRI countries were extracted from the Global Burden of Disease (GBD) 2021 database. Trends in age-standardized incidence (ASIR) and mortality (ASMR) were assessed using estimated annual percentage change (EAPC). Associations with the Social Development Index (SDI) and attributable risk factors were also examined. RESULTS: From 1990 to 2021, global ASIR rose from 21.38 to 24.56 per 100 000 (EAPC = 0.38), while ASMR declined by 0.59% annually; BRI countries showed similar trends. In 1990, Greece had the highest ASIR and Israel the highest ASMR, whereas Bangladesh and Oman had the lowest. By 2021, Lebanon reported the highest ASIR, Georgia the highest ASMR, and Mongolia and Oman the lowest. Turkey showed the largest ASIR increase (EAPC = 6.77). Both ASIR and ASMR were positively correlated with SDI. Risk factors also shifted: in 1990, major contributors were high red meat intake, high body mass index (BMI), and alcohol use; by 2021, high red meat intake, high BMI, and high fasting plasma glucose (FPG) dominated. High BMI and FPG rose markedly, whereas smoking, secondhand smoke, and alcohol use declined. CONCLUSION: Although mortality has fallen, BC incidence continues to rise in BRI countries, especially in low- and middle-SDI regions. Expanded screening, improved healthcare infrastructure, and targeted interventions on modifiable risks are urgently required.