Network Analysis of Health-Related Quality of Life by Frailty Status Among Korean Older Adults: Korea National Health and Nutrition Examination Survey (KNHANES) 2019-2021.

PURPOSE: Frailty in older adults is a multidimensional syndrome associated with adverse outcomes and reduced health-related quality of life (HRQoL). However, differences in HRQoL structure by frailty status are not well understood, and this study aimed to compare HRQoL network structures between frail and non-frail older adults and identify the most influential components in each group. METHODS: We analyzed data from 1311 adults aged ≥ 65 years in the 2019-2021 Korea National Health and Nutrition Examination Survey. Frailty was defined using a modified Fried phenotype, and HRQoL was measured with the Health-Related Quality of Life Instrument with Eight Items. Regularized partial correlation networks were estimated, and centrality, accuracy, and stability were assessed. RESULTS: The Frail group was older, more often female, socioeconomically disadvantaged, and had higher comorbidity burdens than non-frail group. In the frail group, depression-happiness was the strongest link, with working, depression, happiness, and sleep showing high centrality (strength); in non-frail group, climbing stairs-pain was strongest, with working, depression, climbing stairs, and pain central. Across groups, HRQoL was positively associated with better self-rated health, absence of unmet medical needs, and better oral health. CONCLUSION: HRQoL is organized differently according to frailty status: mental-emotional domains dominate the frail network, whereas physical-social domains dominate the non-frail network. The consistently high centrality of Work across groups highlights perceived role participation as a key lever for improving HRQoL in older adults. These findings support frailty-specific, network-informed strategies-emphasizing emotional support in frail older adults and physical resilience in non-frail older adults.