# Life-Course Psychosocial Stress and Risk of Dementia and Stroke in Middle-Aged and Older Adults

## TL;DR

Experiencing stress and trauma during childhood and adulthood is linked to higher risks of dementia and stroke, partly due to depression, according to a study of older adults in China.

## Contribution

The study identifies how life-course psychosocial stress increases dementia and stroke risks, partially mediated by depression, in a Chinese population.

## Key findings

- High levels of adverse childhood and adulthood experiences are significantly associated with increased dementia risk.
- Adverse adulthood experiences are also linked to increased stroke risk.
- Depression partially mediates the associations between adverse experiences and both dementia and stroke.

## Abstract

This cohort study examines associations of adverse childhood and adverse adulthood experiences with the risk of dementia and stroke among middle-aged and older adults in China.

Are adverse childhood experiences (ACEs) and adverse adulthood experiences (AAEs) associated with an increased risk of incident dementia and stroke in middle-aged and older adults in China?

In this cohort study of 11 601 adults, exposure to high levels of ACEs and AAEs was significantly associated with increased dementia risk, with AAEs also being associated with increased stroke risk; depression partially mediated these associations.

These findings suggest that life-course adverse experiences may increase the risks of dementia and stroke partly through depression, underscoring the importance of early identification of psychosocial stressors and preventative strategies aimed at mental health and trauma support.

The associations of adverse childhood experiences (ACEs) and adverse adulthood experiences (AAEs) with incident dementia and stroke in the Chinese population are not well understood.

To investigate the associations of ACEs and AAEs with dementia and stroke incidence, and to examine whether depression mediates these associations.

This population-based cohort study utilized data from the China Health and Retirement Longitudinal Study (June 2015 to December 2020). Participants aged 45 years and older with complete adverse experience data were included and were followed up for a mean (SD) of 4.89 (0.48) years for dementia and 4.84 (0.57) years for stroke. Statistical analysis was performed from August 20, 2025, to November 23, 2025.

ACEs and AAEs were assessed through a structured questionnaire, with cumulative scores calculated for both categories.

Dementia was identified using a standardized cognitive battery and activities of daily living scale, while stroke was determined through self-reported physician diagnosis. Depression was evaluated using the 10-item Centre for Epidemiologic Studies Depression Scale. Cox proportional hazards regression analysis was used to explore the association of ACEs and AAEs with the risk of new-onset dementia and stroke, with results presented as hazard ratios (HRs) with 95% CIs.

Among 11 601 participants (mean [SD] age, 59.18 [9.41] years; 5569 male [48.0%]), 9145 (78.8%) were exposed to at least 1 ACE indicator, 4241 (36.6%) to at least 1 AAE indicator, and 3531 (30.4%) to both ACE and AAE markers. Both ACEs (HR, 1.11; 95% CI, 1.05-1.18) and AAEs (HR, 1.23; 95% CI, 1.14-1.33) were significantly associated with higher hazards of dementia during follow-up, whereas only AAEs were associated with higher hazards of stroke (HR, 1.19; 95% CI, 1.12-1.26). Latent class analysis identified a high-risk ACEs subgroup associated with incident stroke (HR, 1.33; 95% CI, 1.08-1.65). In the joint effects analyses, participants in the high-risk groups for both ACEs and AAEs exhibited higher hazards of dementia (HR, 3.28; 95% CI, 1.54-7.02) and stroke (HR, 2.50; 95% CI, 1.24-5.30). Depression mediated 34.3% of the association of ACEs with dementia (β = 0.10; 95% CI, 0.04-0.17), 20.9% of the association of AAEs with dementia (β = 0.22; 95% CI, 0.13-0.30), and 17.5% of the association of AAEs with stroke (β = 0.18; 95% CI, 0.11-0.24).

In this cohort study, exposure to adverse experiences throughout life was associated with increased risks of dementia and stroke, with depression mediating these associations. These findings highlight the importance of implementing life-course interventions that address both psychological trauma and mental health to reduce the burden of neurovascular diseases.