Association of the red blood cell distribution width-to-albumin ratio with major geriatric syndromes: a retrospective cross-sectional single-centre study

Comprehensive geriatric assessment (CGA) is the cornerstone for identifying multidimensional vulnerability in older adults but is resource-intensive, creating a need for simple triage markers. We investigated the association between the red blood cell distribution width-to-albumin ratio (RAR) and major geriatric syndromes in older outpatients. This retrospective cross-sectional study analysed geriatric outpatients aged ≥ 60 years evaluated at a university hospital geriatrics clinic between January 2020 and September 2025. The primary analysis included the first visit for each patient ( N = 1948). Frailty, functional independence, nutritional status, mood, cognition, sarcopenia risk, handgrip strength, falls, and incontinence were assessed using validated instruments. Logistic regression estimated odds ratios (ORs) per 1-standard deviation (SD) increment in RAR. The primary model adjusted for age and sex, with subsequent models adding body mass index, polypharmacy, anaemia, renal function, and comorbidities. Diagnostic discrimination was evaluated using the area under the receiver operating characteristic curve (AUC), and exploratory optimal cut-points were identified. The cohort was predominantly female (64.3%) with a median age of 73 years. Following adjustment for age and sex, each 1-SD increase in RAR was most strongly associated with frailty (OR 1.86; 95% CI 1.62–2.13), sarcopenia risk (1.80; 1.60–2.02), and malnutrition (1.63; 1.43–1.86). Associations were significant but weaker for cognitive impairment (1.31; 1.18–1.45), depressive symptoms (1.25; 1.12–1.41), falls (1.22; 1.10–1.34), and urinary incontinence (1.15; 1.04–1.26; all P ≤ .01). Associations with frailty, sarcopenia risk, and malnutrition remained robust to full confounder adjustment, whereas the weaker associations attenuated, with incontinence becoming non-significant. Rank correlations were significant but weak to moderate (|ρ| 0.11–0.33). Diagnostic discrimination was modest (AUC 0.54–0.70). Exploratory optimal cut-points ranged from 3.32 to 3.51 for the strongest outcomes, yielding sensitivities of 0.49–0.60 and specificities of 0.71–0.77; these cut-points have not been externally validated. Higher RAR was consistently associated with adverse outcomes across multiple geriatric domains, most strongly and robustly with frailty, sarcopenia risk, and malnutrition. Given its modest discrimination, RAR is best positioned as a low-cost triage signal rather than a definitive diagnostic test, helping to prioritise older adults for CGA. Not applicable.