The roles of health literacy and social support in the association between smartphone ownership and frailty in older adults: a moderated mediation model

Abstract Background Understanding the role of smartphones to promote the health status of older adults is important in the digital society. Little is known about the effects of having smartphones on physical frailty despite its positive effect on the well-being of older adults. This study aimed to explore the association between smartphone ownership and frailty in community-dwelling older adults and its underlying mechanism. Methods We used data from the Korean Frailty and Aging Cohort Study and analyzed 2,469 older adults aged 72–86 years. Frailty, health literacy, and social support were assessed by Fried’s frailty phenotype, the Behavioral Risk Factor Surveillance System health literacy module, and the Enhancing Recovery in Coronary Heart Disease (ENRICHD) Social Support Instrument, respectively. The mediation model and moderated mediation model were estimated, where the mediator was health literacy and the moderator was social support, to explore the relationship between smartphone ownership and frailty. Results Of our study participants, 58.9% owned smartphones, and 10.9% were classified as frail. Smartphone ownership was negatively associated with frailty ( β = −0.623, p < 0.001 ). Health literacy mediated the relationship between smartphone ownership and frailty ( β = −0.154, boot confidence interval CI = − 0.222, − 0.096), and social support moderated the mediation effect ( β = −0.010, Boot CI = − 0.016, − 0.004). Conclusions Owning smartphones among older adults could reduce the risk of frailty. Promoting health literacy and social support among older adults with smartphones would be effective to prevent frailty.