Mediating Role of Health Literacy in Relationship Between Frailty and Medical Costs in Community-Dwelling Older Adults.

This study aims to examine the mediating effects of health literacy on the relationship between frailty and medical costs among community-dwelling older adults. This study conducted a secondary data analysis of the research data that were constructed by linking the Korean Frailty and Aging Cohort Data (KFACD) and the National Health Insurance Database (NHID). Frailty was measured using the Modified Fried Phenotype. Medical costs were calculated using insurance-covered medical costs, including both inpatient and outpatient medical costs, from January 1 to December 31 of the year when the participants were enrolled in the Korean Frailty and Aging Cohort Study. Health literacy was assessed using questions from the Behavioral Risk Factor Surveillance System (BRFSS) conducted by the US Centers for Disease Control and Prevention. To examine the mediating role of health literacy in the relationship between frailty and medical costs, Baron and Kenny's method was used. Linear regression was applied to estimate the association between frailty and health literacy, and Poisson regression was used to model the relationship between frailty, health literacy, and medical costs. Frailty showed a negative correlation with health literacy (r = -0.27, < 0.001) and a positive correlation with medical costs (r = 0.15, < 0.001). Health literacy had a negative correlation with medical costs (r = -0.07, = 0.008). We verified that health literacy played a partial mediating role in the relationship between frailty and medical costs. To reduce medical costs in older adults, intervention measures to improve health literacy as well as prevention and management measures for frailty should be considered simultaneously. In addition, primary medical institutions' active participation in such projects is needed.