Previous studies only focused on changes in the global age-specific incidence and mortality for Alzheimer’s disease and other dementias, failed to distinguish between cohort and period effects, and did not discuss risk factors separately.

In this study, Alzheimer’s disease disability-adjusted life years (DALYs) data to estimate the burden by gender, age, locations, and social-demographic status for 21 regions from 1990 to 2019. Additionally, trend analysis was performed using the age-period-cohort (APC) model and Join-point model.

In most regions, indicators (incidence, mortality, and DALYs) increased steadily with socio-demographic index(SDI) increased. The age effects for Alzheimer’s disease and other dementias showed a significant increase from 40 to 95 years. The cohort effects rate ratios (RRs) had a rapid reduction attributed to smoking, high fasting plasma glucose, and high body mass index (BMI).

Countries in middle-low and low SDI regions have higher levels of risk factor exposure. As a result, rapid and effective government responses are necessary to control dementia risk factors and reduce the disease burden in these countries.