Caring for Grandchildren and Dementia Among Older Adults in China

Importance The association between grandchild care and dementia remains unclear, with previous studies yielding mixed results and unclear mechanisms. Objective To examine the association between grandchild care and dementia odds and to explore the mediating roles of mobile telephone ownership, broadband internet access, and reduced loneliness. Design, Setting, and Participants This cohort study used data from the China Health and Retirement Longitudinal Study from 2013 to 2018. Data analysis was conducted from March 10, 2024, to April 20, 2025. Multistage, stratified, cluster sampling was used to recruit participants from 28 provinces across China. Data were collected through biennial, computer-assisted personal interviews. The analytic sample comprised Chinese adults aged 50 to 79 years who were dementia free at baseline. Exposure Grandchild caregiving was classified into 4 groups: noncaregivers (0 hours per week), nonintensive caregivers (1-39 hours per week), intensive caregivers (≥40 hours per week), and those without grandchildren. Main Outcomes and Measures Dementia was assessed using both self-reports and proxy measures, with dementia defined by scores of 0 to 6 on the modified Telephone Interview for Cognitive Status or a score of 4 or higher on the Informant Questionnaire on Cognitive Decline in the Elderly. Results From an initial cohort of 18 605 participants, 10 058 were included (5062 men [50.3%]; 4996 women [49.7%]; mean [SD] age, 60.9 [7.2] years). Nonintensive grandchild caregiving was associated with lower odds of dementia (odds ratio [OR], 0.76; 95% CI, 0.60-0.97) than no grandchild care. The mediation analysis revealed that the association of nonintensive grandchild care with dementia odds was partially mediated by mobile telephone ownership (17.68%; 95% CI, 2.05%-37.23%), broadband internet access (17.36%; 95% CI, 5.37%-30.05%), and reduced loneliness (16.83%; 95% CI, 4.52%-30.24%), with a combined mediating proportion of 36.99% (95% CI, 25.01%-51.41%). Neither intensive grandchild caregiving nor having no grandchildren was associated with dementia odds, and no significant indirect effects were observed through the mediators examined. Conclusions and Relevance In this cohort study of older Chinese adults, nonintensive grandchild caregiving was associated with lower odds of dementia, partly owing to increased digital technology access and reduced loneliness. Promoting digital inclusion and social engagement could be beneficial for cognitive health, particularly among older adults providing moderate levels of grandchild care.