C-reactive protein-to-albumin ratio as a marker of frailty, impaired physical function, and mortality in older adults with heart failure.

BACKGROUND AND AIMS: Malnutrition and inflammation often coexist in older adults with heart failure (HF), but routine biomarkers that capture these interconnected processes are limited. We evaluated whether the C-reactive protein-to-albumin ratio (CAR), which indicates malnutrition and inflammation, is associated with frailty, physical performance, and mortality.

METHODS AND RESULTS: We conducted a post hoc analysis of consecutive hospitalised HF patients aged ≥ 65 years enrolled in the FRAGILE-HF study, a prospective, multi-centre observational study. CAR, calculated at discharge, was dichotomised at the third quartile (> 0.240). Physical frailty (Fried phenotype) and physical performance (Short Physical Performance Battery [SPPB], 6-min walk distance [6MWD], handgrip strength) were assessed at discharge. Logistic regression was used to evaluate associations with physical frailty and low physical performance. Cox proportional hazards models were used to assess all-cause mortality over 2 years. Of 1332 patients, 1272 (median age: 81 years; 57.7% male) were included in the analysis. After multivariable adjustment, high CAR was associated with Fried frailty (odds ratio [OR], 1.56; 95% confidence interval [CI], 1.18-2.05; P = 0.002), SPPB ≤ 9 (OR, 1.86; 95% CI, 1.38-2.50; P < 0.001), 6MWD < 300 m (OR, 2.23; 95% CI, 1.61-3.09; P < 0.001), and weak handgrip strength (OR, 2.09; 95% CI, 1.49-2.92; P < 0.001). During follow-up, 266 deaths occurred. High CAR independently predicted mortality (hazard ratio [HR], 1.44; 95% CI, 1.11-1.87; P = 0.006).

CONCLUSION: CAR is an inexpensive and readily available marker that integrates inflammation and malnutrition, identifies physical frailty and impaired physical performance, and predicts mortality in older patients with HF.

CLINICAL TRIAL REGISTRATION: UMIN-CTR (UMIN000023929).