Abstract

Lower serum chloride (Cl) levels are strongly associated with increased long-term mortality after admission for acute heart failure (AHF). However, the therapeutic implications of serum Cl levels during AHF are unknown. We sought to determine the short-term clinical response and postdischarge outcomes associated with serum Cl levels in AHF. Serum Cl was measured at randomization (n = 358) and during hospitalization from patients with AHF in the Renal Optimization Strategies Evaluation in Acute Heart Failure trial. Outcomes included diuretic response and renal function at 72 hours and death and rehospitalization at 60 and 180 days. Baseline Cl tertiles were 84 to 98; 99 to 102; and 103 to 117 meq/l. Baseline Cl level was associated with diuretic efficiency (p <0.001) but not change in cystatin C (p = 0.30) at 72 hours and was associated with 60-day death (hazard ratio [HR] 0.86, p = 0.029), 60-day death and rehospitalization (HR 0.90, p = 0.01), and 180-day death (HR 0.91, p = 0.049). These associations were attenuated with additional adjustment for loop diuretic dose (p >0.05). Chloride change correlated with weight change (ρ 0.18, p = 0.001), cystatin C change (ρ -0.35, p <0.001), and cumulative sodium excretion (ρ -0.21, p <0.001) but was not associated with any clinical outcomes (p >0.05 for all). In conclusion, serum Cl levels in AHF were inversely associated with loop diuretic response and were prognostic. However, changes in Cl levels were associated with parameters of decongestion but not with clinical outcomes.