The current status, trends, and challenges of Alzheimer's disease and other dementias in Asia (1990-2036)

Abstract

Background: With global aging, Alzheimer's disease (AD) and other dementias have emerged as significant health threats to the older adults, garnering considerable attention due to their impact on public health. Despite the substantial burden of dementia in Asia, targeted research remains limited. This study aims to assess the current burden, future trends, risk factors, and inequalities in Asia.

Method: The GBD 2021 study was utilized to evaluate the numbers and age-standardized rates (ASRs) of prevalence, mortality, and disability-adjusted life-years (DALYs) of AD and other dementias from 1990 to 2021. Joinpoint regression analysis was performed to assess the trends during this period, while the Autoregressive Integrated Moving Average (ARIMA) model was employed to predict future trends. Additionally, the relationship between disease burden and sociodemographic index (SDI) was also analyzed.

Results: In 2021, Asia experienced a 250.44% increase in prevalent cases, a 297.34% rise in mortality, and a 249.54% surge in DALYs for AD and other dementias compared to 1990. Meanwhile, the age-standardized prevalence rate, age-standardized mortality rate, and age-standardized DALY rate also exhibited varying degrees of rise from 1990 to 2021. Demographically, the disease burden was higher in women and those aged 65 and above. Regionally, the burden was highest in East Asia and relatively low in South and Central Asia. Nationally, China, India, Japan, and Indonesia reported the most cases. Over the next 15 years, the age-standardized prevalence rate in Asia is expected to peak in 2028 before declining, while the age-standardized mortality rate is anticipated to keep rising. An overall "V" shaped association was found between sociodemographic index (SDI) and the age-standardized DALY rate in Asia. Only smoking, high fasting plasma glucose (FPG), and high BMI were identified as causal risk factors within the GBD framework.

Conclusion: The burden of AD and other dementias in Asia has significantly increased over the past three decades and is expected to persistently impact Asian populations, particularly in developing countries experiencing rapid demographic shifts. Women and the older adult should be a focus of attention. It is imperative to implement targeted prevention and intervention strategies, enhance chronic disease management, and control risk factors.

Keywords: Alzheimer’s disease and other dementia; disability-adjusted life years; global burden of disease; mortality; prevalence; risk factors.

Figure 1

The join-point regression analysis of ASPR and ASMR in Alzheimer’s disease and other dementias. (A,C,E) Join-point regression analysis of ASPR in Alzheimer’s disease and other dementias in Asia for both genders (A), male (C), female (E) from 1990 to 2021. (B,D,F) Join-point regression analysis of ASMR in Alzheimer’s disease and other dementias in Asia for both genders (B), male (D), female (F) from 1990 to 2021. ASPR, age-standardized prevalence rate; ASMR, age-standardized mortality rate.

Figure 2

Number of cases (A), mortality number (B), DALYs number (C), prevalence (D), mortality rate (E), and DALYs rate (F) due to Alzheimer’s disease and other dementias in Asia by gender in 2021. DALYs, disability-adjusted life years.

Figure 3

ASPR (A), number of cases (B), ASMR (C), mortality number (D), ASDR (E), and DALYs (F) due to Alzheimer’s disease and other dementias in different countries and regions Asia in 2021. DALY, disability-adjusted life-year; ASPR, age-standardized prevalence rate; ASMR, age-standardized mortality rate; DALYs, disability-adjusted life years; ASDR, age-standardized DALY rate.

Figure 4

The number of cases and ASPR of Alzheimer’s disease and other dementias by year in China (A), India (B), Japan (C), and Indonesia (D) from 1990 to 2021. ASPR, age-standardized prevalence rate.

Figure 5

Predicted trends of prevalence (A, C, E) and mortality rate (B, D, F) in Asia in the next 15 years (2022–2036). ASPR, age-standardized prevalence rate; ASMR, age-standardized mortality rate.

Figure 6

The attributable risk factors of Alzheimer’s disease and other dementias for both genders in Asia in 1990 (A) and 2021 (B).

Figure 7

ASDR of Alzheimer’s disease and other dementias for 5 GBD regions in Asia by SDI, 1990–2021, with 32 data points plotted for each region. Expected values, based on the SDI and disease rates of all locations, are denoted by solid lines. Regions above the solid line indicate a burden exceeding expectations, while those below suggests a burden lower than expected. ASDR, age-standardized DALY rate; SDI, socio-demographic index.