Digital Engagement and Cognitive Function Among Older Adults in China: Cross-Sectional Questionnaire Study and Moderated Mediation Model Analysis (Preprint)

BACKGROUND Given the global demographic shifts and rapid digitalization, digital engagement has emerged as a critical determinant of healthy aging. While previous research has linked digital engagement to cognitive outcomes, the underlying mechanisms remain underexplored among Chinese older adults. OBJECTIVE On the basis of the technological reserve hypothesis, this study aimed to investigate a moderated mediation model linking digital engagement to cognitive function among older adults in China, with digital health literacy and social support as mediators and living arrangements as the moderator. METHODS We conducted a cross-sectional questionnaire survey using stratified multistage sampling from June to November 2024, including 8123 participants. The eHealth Literacy Scale, the Perceived Social Support Scale and the Mini-Cog test were utilized to assess digital health literacy, social support and cognitive function. Mediation and moderated mediation analyses were performed using the PROCESS macro in SPSS with 5000 bootstrap resamples, adjusting for sociodemographic and health covariates. RESULTS Higher digital engagement was associated with better cognitive function. Both digital health literacy and social support served as significant mediators in the relationship. Additionally, living arrangements moderated the associations of digital engagement with cognitive function, digital health literacy, and social support. These effects were stronger among older adults living alone. CONCLUSIONS The study highlights the complex interplay among digital engagement, cognitive function, and psychosocial factors, emphasizing the significant mediating effects of digital health literacy and social support. Living arrangements emerged as a key moderator, with digital engagement having a stronger influence on cognitive function among older adults living alone, underscoring the need for tailored interventions in this vulnerable group. Importantly, the findings suggest that digital technology use can be an effective strategy to mitigate cognitive decline in later life, emphasizing that interventions need to go beyond access and foster capacities to obtain digital information resources and leverage social support.