Comparative Analysis of Burden Trends of Alzheimer's Disease and Other Dementias in China and Globally From 1990 to 2021, With Projections to 2035: Implications for Public Health Prevention Strategies.

INTRODUCTION: This study analyzes trends in the burden of Alzheimer's disease and other dementias (ADODs) in China and globally from 1990 to 2021, with projections to 2035, to inform China's ADODs prevention policies. METHODS: Data from the Global Burden of Disease 2021 Study were used to assess ADODs burdens, including age-standardized rates of incidence, prevalence, mortality, and disability-adjusted life years. Temporal trends were evaluated using Joinpoint regression, and future projections (2022-2035) used a Bayesian Age-Period-Cohort model. Disparities between China and the global average were stratified by age, sex, and period. Analyses were conducted in 2025. RESULTS: From 1990 to 2021, China's ADODs burden grew faster than the global average, especially after 2019. Age-standardized prevalnce rates rose from 6,833.62 to 8,921.45 per 100,000 (average annual percent change=0.81%), versus the global average (average annual percent change=0.09%). Burden increased with age and was higher in females. China's prevalence and incidence peak shifted from age 75-79 years in 1990 to age 80-84 years in 2021, while the global peak stayed at age 80-84 years. Joinpoint analysis showed age-standardized incidence rates and age-standardized prevalence rates rose overall, with peak annual percent changes of 2.90% and 3.62% during 2019-2021. Age-standardized mortality rates and age-standardized disability-adjusted life years also rose rapidly. The BAPC model predicted China's age-standardized rates of incidence, prevalence, and disability-adjusted life years will rise by 2035, while the global average will remain stable. CONCLUSIONS: China's ADODs burden has long exceeded the global average and is projected to remain higher through 2035, disproportionately affecting females and adults aged 80-84 years. This indicates a need for proactive interventions for high-risk populations in future ADODs policies.