Associations between serum electrolyte and short-term outcomes in patients with acute decompensated heart failure

INTRODUCTION: There is a dearth of comprehensive studies on the association between serum electrolyte and adverse short-term prognosis of Chinese patients with acute decompensated heart failure (ADHF). PATIENTS AND METHODS: A total of 5166 patients with ADHF were divided into four serum electrolyte-related study populations (potassium (n = 5145), sodium (n = 5135), chloride (n = 4966), serum total calcium (STC) (n = 4143)) under corresponding exclusions. Different logistic regression models were utilized to gauge the association between these electrolytes or the number of electrolyte abnormalities and the risk of a composite of all-cause mortality or 30-day heart failure (HF) readmission. RESULTS: In multivariable adjusted analysis, patients with potassium below 3.5 mmol/L (odds ratios (ORs) 1.45; 95% confidence interval (CI):1.07–1.95), 4.01–4.50 mmol/L (OR: 1.29, CI: 1.02–1.62), 4.51–5.00 mmol/L (OR: 1.43, CI: 1.08–1.90) and above 5.00 mmol/L (OR: 1.74, CI: 1.21–2.51) had an increased risk of outcome when compared with potassium at 3.50–4.00 mmol/L. Sodium levels were inversely related to the risk of a composite outcome (<130 mmol/L: OR: 2.73 (95% CI, 1.81–4.12); 130–134 mmol/L: OR, 1.97 (CI, 1.45–2.68); 135–140 mmol/L: OR, 1.45 (CI, 1.17–1.81); p for trend < 0.001) in comparison with sodium at 141–145 mmol/L. Chloride < 95 mmol/L corresponded to a higher risk of a composite outcome with an OR of 1.65 (95% CI, 1.16–2.37) in contrast to chloride levels at 101–105 mmol/L. In addition, the adjusted ORs (95% CI) for a composite outcome comparing the STC < 2.00 and 2.00–2.24 vs. 2.25–2.58 mmol/L were 0.98 (0.69–1.43) and 1.13 (0.89–1.44), respectively. Besides that, the number of electrolyte abnormalities was positively related to the risk of a composite outcome (N = 1, OR 1.40, 95% CI: 1.13–1.73; N = 2, OR 2.51, 95% CI: 1.85–3.42; N = 3, OR 2.47, 95% CI: 1.45–4.19; p for trend < 0.001) in comparison with N = 0. CONCLUSIONS: KEY MESSAGES: ADHF patients with baseline serum potassium at first half part of normal range (3.50–4.00 mmol/L) may herald the lowest risk of recent cardiovascular events. Serum sodium and chloride levels exhibit discrepancies in terms of risk of short-term adverse events of ADHF patients. The number of electrolyte abnormalities is a significant predictor of poor short-term prognosis in patients with ADHF. CLINICAL TRIAL REGISTRATION URL: http://www.chictr.org.cn/showproj.aspx?proj=23139. Unique identifier: ChiCTR-POC-17014020.