Objective To assess the burden of thyroid cancer (TC) attributable to high body mass index (BMI) in China from 1990 to 2021. In addition, we analyzed the effects of age, period, and cohort on the trends in TC burden and projected the disease burden from 2022 to 2050. Methods Data derived from the Global Burden of Disease (GBD) 2021 database were employed. Temporal trends were analyzed using Joinpoint regression to calculate the average annual percentage change (AAPC). To elucidate the independent effects of age, period, and cohort, we employed an APC model. In addition, a Bayesian age-period-cohort (BAPC) model was applied to project the future burden of TC associated with high BMI in China during 2022-2050. Results From 1990 to 2021 in China, mortality from TC attributable to high BMI increased, with stable age-standardized mortality rates (ASMR) but rising age-standardized DALY rates (ASDR). APC model analysis revealed that the age effect indicated a gradual increase in disease burden with advancing age. The time effect showed a decline in mortality risk from 1999 to 2004, followed by a rise in disease burden over time thereafter. The cohort effect demonstrated a persistent increase in disease risk, suggesting a growing disease burden among younger cohorts. Conclusion Between 1990 and 2021, China’s TC burden attributable to high BMI increased, with projections indicating further rises among males but declines among females, highlighting the need for targeted obesity prevention.
