Abstract
Background: Physical frailty is common among older patients with coronary artery disease (CAD) and is influenced by perceived social support, health literacy, and a sedentary lifestyle. This study examined the dual mediating roles of health literacy and a sedentary lifestyle in the relationship between perceived social support and physical frailty in older patients with CAD. Methods: This cross-sectional study included data collected from 182 older patients with CAD at a general hospital in Korea between June 2022 and January 2023. Participants completed self-reported questionnaires measuring the main variables and demographic information. Clinical data were obtained from electronic medical records. Results: The mediation hypothesis was tested using a dual mediation model with the PROCESS macro (Model 6) and 95% bias-corrected bootstrap confidence intervals. Perceived social support indirectly influenced physical frailty through three pathways: health literacy alone, sedentary lifestyle alone, and a sequential process in which health literacy influenced sedentary lifestyle and ultimately physical frailty. Conclusions: This study identified a strong mediating effect of health literacy and a sedentary lifestyle on the relationship between perceived social support and physical frailty. A built environment of perceived social support among older patients with CAD improves health literacy, modifies sedentary lifestyles, and helps prevent physical frailty. Thus, healthcare professionals should evaluate the perceived social support, health literacy, and sedentary lifestyle of older patients when developing physical frailty prevention programs.