Abstract
OBJECTS: This study examines how social isolation affects the relationship between childhood friendships and frailty in older adults, aiming to provide insights for improving their health. DESIGN: A Longitudinal study guided by the Strengthening the Reporting of Observational Studies in Epidemiology. METHODS: Data from the CHARLS database (2014, 2015, 2018) were analyzed. Correlation, regression, and mediation analyses were used to explore the relationships between childhood friendships, social isolation, and frailty. RESULTS: Among 4,132 participants, 1,363 (33.0%) were identified as frail. Childhood friendships were negatively associated with frailty and social isolation, while social isolation was positively associated with frailty. Mediation analysis showed a significant indirect effect (-0.0040, 95% CI: -0.0055, -0.0027), indicating that social isolation mediates the relationship between childhood friendships and frailty. CONCLUSION: Social isolation can exacerbate the effects of adverse childhood experiences on subsequent frailty. Targeted interventions should be developed to reduce social isolation and maintain health in older adults.