Cumulative effect of intrinsic capacity domains on geriatric syndromes and functionality in older inpatients

Introduction Intrinsic capacity (IC), as defined by the World Health Organization, represents the composite of an individual’s physical and mental capacities and provides a multidimensional framework for assessing older adults’ functional reserve. It includes five domains: locomotion, vitality, cognition, psychological well-being, and sensory function. This study aimed to examine the associations between IC domains and common geriatric syndromes in hospitalized older adults. Methods In this retrospective observational study, 245 patients aged ≥ 60 years who underwent comprehensive geriatric assessment were included. IC was evaluated across five domains using standard tools: gait speed, self-reported sensory deficits, Standardized Mini-Mental State Examination (S-MMSE), Euro Quality of Life 5 Domain (EuroQOL-5D) and Mini Nutritional Assessment. The IC score ranges from 0 to 5, with higher scores indicating better intrinsic capacity, and a score ≤ 2 representing moderate–severe decline. Geriatric syndromes assessed were frailty, probable sarcopenia, falls, urinary incontinence, and functional impairments in Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL). Logistic regression models identified predictive IC domains, adjusting for age, sex, polypharmacy, and comorbidity. Results Nearly 60% of participants had moderate to severe IC decline (score ≤ 2). Vitality and locomotor impairments were the most common. Cognitive and vitality impairments were strongly associated with both ADL and IADL disability ( p < 0.001), while locomotor and vitality impairments predicted probable sarcopenia and frailty ( p < 0.01). Cognitive impairment was linked to a nearly six-fold increased fall risk (OR = 5.86, 95% CI: 2.51–13.68, p < 0.001). The models showed good discrimination, with an area under the curve value of 0.723 for falls and 0.854 for ADL disability. Conclusions IC impairments, particularly in cognition, vitality, and locomotion, are prevalent and predictive of major geriatric syndromes in hospitalized older adults. Routine IC assessment may help identify at-risk individuals and inform targeted interventions.