Prognostic nutritional index in elderly patients hospitalized for acute heart failure

Abstract

Aims: Acute heart failure (AHF) represents a frequent cause of hospitalization and is associated with significant mortality among elderly patients. Risk assessment models like the prognostic nutritional index (PNI) have been proposed to stratify the risk of death and identify patients requiring more intensive levels of care. We evaluated the predictive value of PNI for in-hospital and overall mortality in a cohort of consecutive elderly patients hospitalized for AHF. Methods and results: Prognostic nutritional index, laboratory, and clinical parameters were collected upon admission. PNI values were calculated from albumin concentration and lymphocyte count and reported on a continuous scale with lower values indicating worse prognosis. The primary outcome was overall all-cause mortality defined as death from any cause occurring during hospitalization up to 6 months after discharge. Cox proportional regression analysis was used to calculate hazard ratios (HRs) and the relative 95% confidence intervals (CIs). The study population included 344 patients (median age 84 years, range 65 to 101). During a median follow-up of 158 days (range 2 to 180 days), 75 patients (21.8%) died of whom 28 (8.1%) died during hospitalization. The median PNI was 34 (range 17 to 55). In univariable analysis, PNI was inversely associated with overall mortality (HR 0.90; 95% CI, 0.87 to 0.94) and in-hospital mortality (HR 0.91; 95% CI, 0.85 to 0.98). In multivariable analysis, PNI remained a significant predictor of overall mortality (HR 0.93; 95% CI, 0.89 to 0.98) after adjustment for age, anaemia, NT-proBNP values, and bedridden status. PNI values ≤34 were associated with a two-fold higher risk of overall mortality (HR 2.54; 95% CI, 1.52 to 4.24) and three-fold higher risk of in-hospital mortality (HR 3.37; 95% CI, 1.14 to 9.95). Conclusions: Low PNI values are associated with short-term and long-term mortality among elderly patients hospitalized for acute decompensated heart failure. Future studies are warranted to confirm these findings and evaluate the use of PNI to guide therapeutic decisions.