Intrinsic capacity and its dimensions in relation to functional ability in older adults: A systematic review and...

This study aims to explore the association between declines in intrinsic capacity and its individual domains with functional impairment in older adults and to compare the predictive ability of overall intrinsic capacity and its specific domains for functional disability.

We systematically searched PubMed, Embase, Cochrane Library, Web of Science, SinoMed, CNKI, Wanfang, and VIP databases from inception to December 26, 2024. Meta-analysis was conducted using RevMan 5.4. Study quality was assessed with the Newcastle-Ottawa Scale, and evidence quality was evaluated using GRADE guidelines. The study protocol was registered in PROSPERO (CRD42025634431).

This meta-analysis included 15 longitudinal studies with 53,648 participants. Declines in locomotion, cognition, psychological well-being, and vitality were significantly associated with increased Activities of Daily Living (ADL) disability risk. Vision impairment also elevated ADL disability risk but hearing loss did not. Overall intrinsic capacity decline was linked to higher ADL disability risk (OR = 1.22, 95 % CI [1.16, 1.28]), with locomotion demonstrating stronger predictive power than overall intrinsic capacity. For instrumental activities of daily living (IADL) disability, declines in locomotion, cognition, psychological well-being, and vitality were significant risk factors. Sensory functions showed no significant association. Overall intrinsic capacity decline was strongly associated with IADL disability risk (OR = 1.41, 95 % CI [1.29, 1.54]), with no individual dimension showing significantly greater predictive power than overall intrinsic capacity. The GRADE evidence quality was rated as moderate.

This study confirms the role of overall intrinsic capacity and its individual domains in predicting functional impairment in older adults. It also compares the predictive value of overall intrinsic capacity with that of its specific domains, identifying locomotion decline as a key driver of functional impairment. Future research should further explore the longitudinal interactions among multiple intrinsic capacity domains using standardized intrinsic capacity assessment methods to refine the theoretical framework of healthy aging.