# Trajectories of social participation and risk of cognitive impairment in Chinese older adults: A six-year longitudinal study

## TL;DR

Long-term social participation in older Chinese adults is linked to lower risk of cognitive decline, suggesting that maintaining social activities can help protect brain health.

## Contribution

The study identifies distinct social participation patterns and their long-term associations with cognitive impairment in older Chinese adults.

## Key findings

- Maintaining or increasing social participation is associated with a significantly lower risk of cognitive impairment.
- Stable high or stable intermediate levels of social activity are linked to better cognitive outcomes.
- A moderate decline in social participation does not significantly affect cognitive impairment risk.

## Abstract

The growing burden of cognitive decline represents a significant public health concern in aging populations, particularly in China. Social participation is a modifiable factor that may protect against cognitive decline, yet its long-term dynamic association with cognitive impairment remains insufficiently characterized.

This study aimed to delineate long-term trajectories of social participation and determine their association with cognitive impairment in Chinese older adults.

: Longitudinal cohort study.

The study utilized data collected in 2013, 2015, and 2018 from the China Health and Retirement Longitudinal Study.

We included 3074 Chinese adults aged ≥60 years who were free of cognitive impairment in 2013, had complete social participation data in 2013/2015/2018, and completed cognitive assessments in 2018

Not applicable.

Social participation was derived from CHARLS self-reported activity items and frequency and summed into a composite score (range 0–33). Cognitive performance was assessed using episodic memory (immediate and delayed 10-word recall) and mental status (orientation, serial subtraction, and figure drawing), yielding a global score (range 0–31); cognitive impairment was defined as a score <11. Group-based trajectory modeling identified five social participation trajectories. Multivariable logistic regression estimated odds ratios (ORs) for cognitive impairment adjusting for sociodemographic, health, and behavioral covariates.

Five distinct social participation trajectories were identified. In the fully adjusted model, relative to the “stable low” group, those in the “low baseline–increasing” (OR = 0.66, 95% CI: 0.47–0.92), “stable intermediate” (OR = 0.75, 95% CI: 0.58–0.97), and “stable high” (OR = 0.41, 95% CI: 0.22–0.76) groups had markedly reduced chances of cognitive impairment, while no significant link was found for the “moderate decline” group (OR = 0.90, 95% CI: 0.71–1.17).

Maintaining or increasing one’s social activities was linked to a notably lower likelihood of cognitive decline. These results highlight the importance of social involvement patterns as a modifiable factor for fostering cognitive strength. Interventions to maintain or enhance participation are therefore a viable strategy for the primary prevention of cognitive decline in older adults.