Lifestyle and Socioeconomic Transition and Health Consequences of Alzheimer's Disease and Other Dementias in Global, from 1990 to 2019.

Background: 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.

Methods: 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.

Results: 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).

Conclusions: 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.