Background. Frailty is highly prevalent among patients with heart failure (HF) and is associated with adverse clinical outcomes. Chronic kidney disease (CKD) frequently coexists with HF and may further increase risk. However, the clinical profile linking frailty and CKD remains insufficiently characterized. This study aimed to determine the prevalence and clinical correlates of frailty in outpatients with HF and to assess whether its prognostic significance varies across CKD severity. Methods. A prospective, observational cohort of HF outpatients was enrolled. Frailty was defined according to Fried’s phenotype (≥3 criteria). Factors associated with frailty were identified using logistic regression. The primary endpoint was a composite of all-cause mortality or HF hospitalization over one year. Cox proportional hazards models were used to evaluate associations between frailty and outcomes and to test its interaction with CKD. Results. A total of 459 HF outpatients (median age 75 [IQR 68–82] years; 72% men) were included. Frailty was present in 39.9% of patients and increased progressively with worsening renal function—from 14% in those with eGFR >60 to 38% in eGFR 30–60 and 48% in eGFR <30 mL/min/1.73 m² (p < 0.001). In multivariate analysis, older age, prior stroke, higher CA125 levels, and lower eGFR were independently associated with frailty. Frail patients had a higher risk of all-cause death or HF hospitalization (adjusted HR 2.09; 95% CI 1.22–3.58; p = 0.007), with an amplified effect among those with advanced CKD (HR 5.02; 95% CI 2.46–10.22; p < 0.001). Conclusions. In HF outpatients, frailty is common and closely linked to renal dysfunction. Its coexistence with advanced CKD identifies a subgroup at the highest risk of adverse outcomes. Combined assessment of frailty and renal function may enhance prognostic precision and guide more individualized therapeutic strategies.

Background/Objectives: Frailty and congestion are highly prevalent in patients with heart failure (HF) and are independently associated with adverse outcomes. However, their interrelationship and combined prognostic significance remain incompletely understood. We aimed to investigate the association between frailty and congestion phenotypes in older patients with HF and to evaluate their combined impact on clinical outcomes. Methods: We prospectively included 308 ambulatory patients aged ≥65 years with chronic HF from a specialized HF clinic between 2022 and 2024. Frailty was assessed using the Fried phenotype. Congestion was defined by clinical signs and/or elevated NT-proBNP (≥1000 pg/mL) and CA125 (≥35 U/mL). Associations between congestion and frailty were evaluated using logistic regression and restricted cubic spline analyses. The primary endpoint was a composite of all-cause mortality or HF hospitalization at 1 year. Results: Frailty was present in 49.7% of patients and congestion in 79.9%. Frailty prevalence increased progressively across congestion phenotypes, from 21.0% in patients without congestion to 70.8% in those with combined clinical and biochemical congestion (p < 0.001). Congestion was also associated with worse nutritional status and reduced muscle strength. In multivariable analyses, frailty and congestion remained independently associated with adverse outcomes. Their coexistence identified the subgroup with the highest risk of death or HF hospitalization (HR 25.54, 95% CI 3.46–188.26; p = 0.001). Conclusions: In older ambulatory patients with HF, frailty and congestion frequently coexisted and identified patients at increased risk of adverse outcomes, particularly when clinical and biochemical congestion were present. These findings support combining frailty evaluation with congestion assessment for prognostic stratification.