Serial change in serum chloride during hospitalization could predict heart failure death in acute decompensated heart failure patients

Background: Although hyponatremia predicts morbidity and mortality in acute decompensated heart failure (ADHF), hypochloremia is also independently associated with poor prognosis in ADHF. Little is known, however, about the prognostic value of serial change in serum chloride during hospitalization in ADHF patients. Methods and Results: We prospectively studied 208 ADHF survivors after discharge and divided them into 4 groups according to serum chloride on admission and at discharge: (1) persistent hypochloremia group (n=12), hypochloremia both on admission and at discharge; (2) progressive hypochloremia group (n=42), development of hypochloremia after admission; (3) improved hypochloremia group (n=14), hypochloremia only on admission; and (4) no hypochloremia group, no hypochloremia during hospitalization (n=140). During a mean follow-up period of 1.86±0.76 years, 20 of 208 patients had heart failure death (HFD). In a model adjusted for hyponatremia, hypochloremia both on admission and at discharge was still significantly associated with HFD. Hyponatremia, however, was not significantly associated with HFD after adjustment for hypochloremia. Patients with persistent hypochloremia (HR, 9.13; 95% CI: 2.56–32.55) and with progressive hypochloremia (HR, 4.65; 95% CI: 1.61–13.4) had a significantly greater risk of HFD than those without hypochloremia during hospitalization. Conclusions: Both persistent hypochloremia and progressive hypochloremia during hospitalization are associated with HFD in ADHF patients.