Association of Computer and Smartphone Use, Health Literacy, and Frailty Among Community-Dwelling Older Adults: The Higashiura Study.

AIM: Frailty is an age-related condition involving physical, psychological, and social functional decline, and global efforts to prevent frailty using information and communication technology have recently expanded. This study aimed to examine whether computer and smartphone use among community-dwelling older adults is associated with frailty mediated by health literacy. METHODS: Participants were community-dwelling adults aged ≥ 65 years without long-term care certification participating in the 2024 Higashiura Study. The primary outcome was frailty assessed using the revised Japanese Cardiovascular Health Study criteria. In this cross-sectional study, the independent variable was computer and smartphone use for health information acquisition and health management. The mediating variable was health literacy measured using the Communicative and Critical Health Literacy Scale. Mediation analysis was conducted, adjusting for age, gender, educational attainment, and household income, with 95% confidence intervals (CIs) estimated via bootstrapping. RESULTS: Of 451 participants, 423 were analyzed. Frailty prevalence was 15 participants (3.5%), and 143 (33.8%) of participants reported computer and smartphone use. In the main outcome analysis (frailty vs. non-frailty), mediation analysis showed a non-significant direct effect (β = -0.818, 95% CI: -2.127 to 0.490) and a significant indirect effect through health literacy (β = 0.323, 95% CI: 0.084-0.698). No significant indirect effect was observed for the sub-outcome analysis (robust vs. non-robust). CONCLUSIONS: Among community-dwelling older adults, not engaging in health-related computer and smartphone use was associated with frailty, and lower health literacy may be involved in this association. Further longitudinal studies are needed to clarify temporal relationships between these factors.