The evolving burden of early-onset Alzheimer's disease and other dementias in BRICS countries: Insights from the Global Burden of Disease Study 2023 and projections to 2035

BackgroundThe burden of early-onset Alzheimer's disease and other dementias (EOAD) in BRICS nations (Brazil, Russia, India, China, South Africa, Egypt, Ethiopia, Iran, Saudi Arabia, the United Arab Emirates, and Indonesia) is poorly characterized.ObjectiveOur aims are to characterize national trends, identify high-burden populations, quantify sex- and risk factor-specific burdens, and inform targeted prevention and age-inclusive healthcare strategies in these key nations.MethodsUsing data from the Global Burden of Disease Study (GBD) 2023, we analyzed EOAD (ages 40-64) across BRICS countries from 1990-2023, employing decomposition, Joinpoint regression, and Bayesian Age-Period-Cohort modeling to project trends to 2035.ResultsPrevalent cases increased in all nations, led by China. Age-standardized incidence rose in China (average annual percentage change 0.461%) but declined in India and Iran. Females consistently bore a higher burden. Ambient particulate matter drove substantial disability-adjusted life years in Iran (74.43/100,000) and Saudi Arabia, while household air pollution was key in Ethiopia and India. Projections indicate divergence by 2035, with Russia's incidence rising to 56.22 and Saudi Arabia's prevalence falling to 160.10 per 100,000.ConclusionsEOAD burden in BRICS is heterogeneous, driven by aging, sex, and modifiable risks, necessitating tailored public health strategies.