Albuminuria Levels and Geriatric Outcomes in Predialysis: Chronic Kidney Disease: Falls, Fear of Falling, and Frailty...

Background: Chronic kidney disease (CKD) accelerates biological aging and amplifies the risk of adverse geriatric outcomes. Albuminuria reflects systemic endothelial dysfunction beyond renal damage, yet its specific relationship with falls, fear of falling, and frailty in predialysis CKD patients remains underexplored. Objectives: We aimed to evaluate the association between albuminuria levels (urinary albumin-to-creatinine ratio, ACR) with falls, fear of falling (Falls Efficacy Scale, FES), and frailty (FRAIL scale and Clinical Frailty Scale, CFS) in older adults with CKD. Methods: This cross-sectional study analyzed 295 patients aged ≥60 years attending nephrology and geriatrics clinics at Kayseri City Hospital, Turkey (April-June 2025). ACR was categorized per KDIGO (A1: <30, A2: 30-300, A3: ≥300 mg/g). Inflammatory indices (NLR, SII, CAR) were calculated. Hierarchical multivariable logistic regression and ROC analyses were performed. Results: Fall prevalence showed a clear dose-response across ACR categories: 31.2% (A1), 72.0% (A2), and 93.2% (A3) (p < 0.001). In the fully adjusted model, each unit increase in log-ACR was associated with a 3.84-fold increase in fall odds (OR 3.84, 95% CI 2.74-6.65). Although bivariate ACR-frailty associations were non-significant, fully adjusted models uncovered independent associations across both instruments and thresholds: FRAIL ≥ 3 (OR 1.41, 95% CI 1.05-2.03), FRAIL ≥ 2 (OR 1.49, 95% CI 1.08-2.21), CFS ≥ 5 (OR 1.87, 95% CI 1.38-2.83), and CFS ≥ 4 (OR 1.37, 95% CI 1.02-1.93). ACR showed good discriminative ability for falls (AUC 0.773, optimal cut-off 21.70 mg/g) but poor discrimination for frailty (AUC 0.50-0.54). The ACR-fall association was stronger in patients with GFR < 60 (OR 4.48) than GFR ≥ 60 (OR 2.18). Conclusions: Albuminuria is a strong, independent, and graded predictor of falls in older CKD patients, with a nearly 4-fold increase in risk per log-unit ACR increase after full adjustment. ACR measurement, already routine in CKD monitoring, could help identify older patients at increased fall risk and guide targeted geriatric assessment. However, ACR showed poor standalone discriminative ability for frailty across all definitions (AUC 0.50-0.54), establishing that it cannot serve as a frailty screening tool in isolation.