Extracellular water to lean body mass ratio predicts mortality in patients with chronic heart failure: A prospective,...

Chronic fluid accumulation and malnutrition represent key pathophysiological mechanisms linked to adverse outcomes in chronic heart failure (CHF). We developed a composite index, the extracellular water (ECW) -to-lean body mass (LBM) ratio (ELR), which concurrently reflects these pathological processes, and assessed its prognostic utility in CHF patients.

A prospective cohort of 401 consecutive patients with CHF was enrolled between August 2019 and October 2021. The InBody S10 device measured ECW and LBM. The study evaluated long-term all-cause and cardiovascular mortality as primary endpoints.

The mean age of this cohort was 69.51 years and 62.3 % were male. ELR showed superior predictive value for long-term all-cause mortality (AUC = 0.686) compared to ECW (0.502) and LBM (0.546), with similar patterns observed for cardiovascular mortality (0.649 vs. 0.525 and 0.564, respectively). The optimal ELR cutoff was 0.308 by Youden index analysis. Over a median of 1200-day follow-up, patients with ELR > 0.308 had markedly higher all-cause (40.1 % vs. 15.6 %, p < 0.001) and cardiovascular mortality rates (28.4 % vs. 11.2 %, p < 0.001). Kaplan-Meier curves revealed significantly divergent survival outcomes for both endpoints (log-rank p < 0.001). Multivariable analysis demonstrated ELR > 0.308 independently predicted all-cause (HR = 1.834, 95 %CI 1.134-2.968, p = 0.013) and cardiovascular mortality (HR = 2.026, 95 %CI 1.138-3.609, p = 0.017). These associations remained robust across all examined subgroups.

The ELR represents a novel index that concurrently reflects both volume status and nutritional status in CHF patients, demonstrating potential as a long-term prognostic biomarker for this population.