Predictors of functional capacity in younger and elderly chronic heart failure patients: an observational study

The prevalence of chronic heart failure (CHF) in the elderly population is growing. Identification of risk factors in patients with CHF is important. Recent studies suggest that red cell distribution width (RDW) has prognostic significance in these patients. We aimed to evaluate the relationship of RDW with clinical and laboratory parameters in patients with young and elderly CHF patients.

We evaluated patients with CHF with an ejection fraction (EF) of <50% in this observational cross-sectional study. Exclusion criteria were decompensated CHF, malignancy and end-stage renal disease. Clinical information, functional capacity (FC), hemoglobin, RDW, EF, and pro-B type natriuretic peptide (proBNP) were recorded. The younger and elderly groups were compared and correlation of RDW with clinical and laboratory parameters were analyzed in each group. Ordinal regression analysis was performed to determine independent correlates of increased FC.

Seventy young and 47 elderly cases were enrolled. The groups were similar regarding EF, proBNP and FC. RDW showed stronger correlation with FC in the young group (r=0.627, p<0.001) compared to the elderly group (r=0.332, p=0.023). In the younger group, there was a negative correlation between RDW and EF (r=-0.278, p=0.021) and a positive correlation between RDW and proBNP (r=0.487, p<0.001). RDW (OR=16.36, 95% CI 0.33-0.96, p<0.001), EF [OR=7.75, 95% CI (-0.16)-(-0.03), p=0.005] and usage of RAS inhibitors (OR=6.7, 95% CI 0.57-3.36, p=0.007) were independent predictors of increased FC.

We found a stronger correlation between RDW and EF, proBNP and FC in the younger patients compared the elderly group. RDW is a simple, inexpensive and easily accessible parameter that may be considered risk predictor especially in younger patients with CHF.