Positive association between sodium-to-chloride ratio and in-hospital mortality of acute heart failure

Area of Science:

• Clinical Medicine
• Cardiology
• Critical Care

Background:

• Blood sodium and chloride levels are recognized prognostic indicators for various medical conditions.
• The prognostic significance of the sodium-to-chloride (Na/Cl) ratio in acute heart failure (AHF) has not been previously explored.

Purpose of the Study:

• To investigate the prognostic value of the admission sodium-to-chloride (Na/Cl) ratio for in-hospital mortality in patients with acute heart failure (AHF).
• To determine if the Na/Cl ratio offers superior predictive capability compared to individual sodium or chloride levels.

Main Methods:

• Utilized data from the Medical Information Mart for Intensive Care IV database, including 7844 adult patients with AHF.
• Employed multivariable Cox regression, Kaplan-Meier curves, receiver operator characteristic (ROC) curve analysis, and subgroup analyses.
• Categorized patients based on admission Na/Cl ratio tertiles and adjusted for potential confounders.

Main Results:

• An elevated baseline Na/Cl ratio was significantly associated with increased in-hospital mortality risk in AHF patients (HR=1.34).
• A dose-response relationship was observed, with higher Na/Cl ratio tertiles showing progressively greater hazard ratios for mortality.
• The Na/Cl ratio demonstrated superior prognostic value in predicting in-hospital mortality compared to sodium or chloride levels alone (ROC AUC 0.564 vs. 0.505 and 0.544).

Conclusions:

• The admission sodium-to-chloride (Na/Cl) ratio is an independent and significant predictor of in-hospital mortality in critically ill patients with acute heart failure (AHF).
• The Na/Cl ratio provides a more sensitive prognostic marker for AHF mortality than individual electrolyte measurements.
• This finding suggests the Na/Cl ratio can be a valuable tool for risk stratification in AHF management.