Sarcopenia evaluated by fat-free mass index is an important prognostic factor in patients with chronic heart failure

Abstract

Background and aim: Chronic heart failure (CHF) is a major cause of morbidity and mortality, and cardiac cachexia and sarcopenia are serious complications associated with weight loss and increased catabolism. Fat-free mass index (FFMI) is an indicator of resting energy expenditure and is used for the clinical diagnosis of sarcopenia. In the present study, we investigated the impact of sarcopenia, as evaluated by FFMI, on cardiac prognosis in patients with CHF.

Methods and results: We calculated FFMI in 267 CHF patients who were prospectively followed until they died due to cardiac event, or until they were re-hospitalized. Fat-free mass (FFM) was estimated by the formula [FFM (kg)=7.38+0.02908×urinary creatinine (mg/day)] and normalized by the square of the patient's height in meters to calculate FFMI. During the follow-up periods, there were 83 cardiac events, including 19 cardiac deaths. FFMI was lower in patients with cardiac events than in those without (17.0 kg/m(2) vs. 17.6 kg/m(2), P=0.045). Multivariate Cox hazard analysis revealed that decreased FFMI was associated with an unfavorable outcome (adjusted hazard ratio 0.68, 95% confidence interval 0.47-0.98). The patients were divided into two groups according to their median FFMI. The Kaplan-Meier analysis revealed that significantly higher cardiac event rate was observed in the low-FFMI group (log-rank test, P=0.017).

Conclusions: Decreased FFMI was associated with an unfavorable prognosis in patients with CHF.

Keywords: Cachexia; Heart failure; Prognosis; Sarcopenia.