Abstract 16345: Increase in Serum Chloride Level During Hospitalization Leads to Improved Clinical Outcomes in Patients With Heart Failure

Abstract

Introduction: Serum chloride levels both at admission and at discharge in patients with heart failure (HF) are independently associated with the incidence of adverse clinical outcomes. However, there has been few reports focusing on the prognostic impact of the change in serum chloride level during the hospitalization on the long-term prognosis after discharge. Hypothesis: We thus hypothesized that changes in serum chloride during the hospitalization is an independent prognostic predictor after discharge in HF patients. Methods: This observational study included 1,913 consecutive patients who admitted to hospital due to worsening of HF and discharged alive in a single university hospital. After excluding patients who received regular hemodialysis, 1,762 patients were ultimately analyzed. The primary endpoint of this study was death from any cause. Result: Overall serum chloride level was significantly decreased from the admission to discharge (103 [100-106] mEq/L to 102 [99-105] mEq/L, P<0.001). During the observation period with 512 days of median follow-up, 286 patients (16.2%) died. Multivariate Cox regression analysis revealed that increase in serum chloride level during the index hospitalization was independently associated with lower rates of mortality, even after the adjustment of diverse covariates including serum chloride level at admission (hazard ratio (HR): 0.94, 95% confidence interval: 0.90-0.98). When dividing the study population into tertiles by chloride levels at admission, patients with the lower baseline chloride level had the greater reduction in HR of the primary endpoint by the increase of chloride level during the hospitalization (Figure). Conclusion: Increase in serum chloride level during hospitalization may be associated with better post-discharge prognosis in HF patients. This could be a new therapeutic target for heart failure to improve long-term prognosis.