Prevalence and Prognostic Impact of Multiple Frailty Domain in Japanese Older Adults.

Objectives: In this observational study, we aimed to evaluate the independent and overlapping effects of multiple frailty domains on long-term care insurance (LTCI) use.

Design: Population-based cohort design.

Setting And Participants: In total, 9804 community-dwelling older adults were recruited from the National Center for Geriatrics and Gerontology-Study of Geriatric Syndromes.

Methods: The physical domain of frailty was assessed using the revised Japanese version of the Cardiovascular Health Study criteria. The cognitive domain of frailty was identified as impairment of memory, attention, executive function, or processing speed using standardized thresholds established for each domain in population-based cohorts. The social domain was operationalized using the National Center for Geriatrics and Gerontology-Social Frailty Scale. The use of LTCI was prospectively determined over 60 months using data extracted from the Japanese long-term care insurance system.

Results: The data from 7745 participants were analyzed, of whom 793 (10.2%) required LTCI certification within 60 months (interquartile range: 60-60 months). The Kaplan-Meier curve analysis demonstrated that a high number of frailty domains was associated with incident LTCI use. The proportions of incident LTCI use were 6.0%, 12.4%, 30.1%, and 43.9% for non-frail participants and those with impairments in 1, 2, and 3 frailty domains, respectively. In the multivariate Cox regression model, physical, cognitive, and social domain impairments independently increased the risk of incident LTCI use [physical domain impairment, hazard ratio (HR), 1.67; 95% CI, 1.39-2.01; cognitive domain impairment, HR, 1.59; 95% CI, 1.37-1.84; social domain impairment, HR, 1.26; 95% CI, 1.05-1.50].

Conclusions And Implications: Overlapping frailty domains were strongly associated with incident LTCI use among community-dwelling older adults. These findings emphasize the importance of assessing multiple frailty domains and tailoring interventions according to the unique circumstances of older adults to prevent functional disabilities.