Prognostic Value of Frailty Assessment Combining the Frailty Index Based on Laboratory Tests With the Clinical Frailty Scale in Patients With Acute Heart Failure

BACKGROUND: Heart failure (HF) is often complicated by frailty. We evaluated the prognostic value of the Frailty Index based on laboratory tests (FI-lab) and the Clinical Frailty Scale, as well as their combined use, for adults with acute HF. METHODS: This study was a post hoc analysis of the POPEYE-AHF (Prospective Observational Study on Acute Pharmacotherapy and Prognosis in Management of Acute Heart Failure) registry, a prospective observational study evaluating the treatment and characteristics of patients with acute HF. At discharge, 975 patients had available FI-lab data, while 637 patients had available Clinical Frailty Scale data. The FI-lab was determined at discharge by the proportion of 21 laboratory items with abnormal results. The outcomes were all-cause death, HF hospitalization, and the composite of both. RESULTS: At baseline, the median age was 80 years, and 45.0% of the patients with FI-lab data were women. Multivariable Cox proportional hazards regression revealed that the measured FI-lab was associated with all outcomes (all-cause death: hazard ratio [HR], 1.38 [95% CI, 1.15–1.67], P=0.001; HF hospitalization: HR, 1.15 [95% CI, 1.00–1.32], P=0.044; composite outcome: HR, 1.21 [95% CI, 1.08–1.37], P=0.002) after full adjustment. When dividing patients into the high and low FI-lab subgroups (median cutoff, 0.48), high FI-lab was associated with all-cause death (HR, 2.11 [95% CI, 1.31–3.41], P=0.002) and the composite outcome (HR, 1.40 [95% CI, 1.05–1.88], P=0.023). High FI-lab/high Clinical Frailty Scale was associated with all-cause death after adjustment (HR, 2.62 [95% CI, 1.38–4.99], P=0.003). CONCLUSIONS: FI-lab identified high-risk adults with acute HF. The combined use of the Clinical Frailty Scale and FI-lab identified adults at high risk of all-cause death.