Comparative analysis of the burden of young-onset and late-onset dementia in China from 1990 to 2021: A study based on GBD 2021 data.

Abstract

Background: Most epidemiological studies on dementia in China have focused on the elderly population, with a lack of systematic comparisons between the burden of young-onset dementia (YOD) and late-onset dementia (LOD).

Methods: Based on data from the Global Burden of Disease (GBD) study, this research systematically evaluated changes in the burden of YOD and LOD in China over different time periods. The analysis employed average annual percentage change (AAPC), Bayesian age-period-cohort (BAPC) modeling, decomposition analysis, risk factor attribution analysis, health inequality analysis, and frontier analysis.

Results: AAPC analysis showed that the growth rate of YOD has significantly outpaced that of LOD since 2012. Forecasting results indicated that the age-standardized rates for both YOD and LOD are expected to continue rising in the future. Decomposition analysis revealed that between 1990 and 2021, the main drivers of the increasing YOD burden shifted from population growth to epidemiological changes and population aging, whereas population growth remained the dominant driver for LOD. Risk factor analysis indicated that the impact of high BMI on both YOD and LOD has become increasingly pronounced. Health inequality and frontier analyses suggested that, although disparities in YOD and LOD burden across different SDI regions were not significant, there remains substantial room for improvement in managing both conditions in China.

Conclusion: In recent years, YOD has exhibited a more rapid increase compared to LOD, with its driving forces gradually shifting from population-related factors to epidemiological transitions. This highlights the need to strengthen identification and intervention strategies targeting younger and middle-aged populations. Tobacco use, high fasting plasma glucose, and high BMI are key modifiable risk factors shared by both YOD and LOD, with particular attention needed on the sustained impact of high BMI. Although international disparities in health inequality are not pronounced, China still holds considerable potential for improvement in the prevention and control of both YOD and LOD. Future interventions should be more forward-looking, systematic, and tailored to specific population groups.