Relationship between admission serum sodium concentration and clinical outcomes in patients hospitalized for heart failure: an analysis from the OPTIMIZE-HF registry

Aims Hyponatraemia has been shown to be an independent predictor of mortality in selected patients with heart failure enrolled in clinical trials. The predictive value of hyponatraemia has not been evaluated in unselected patients hospitalized with heart failure. Methods and results OPTIMIZE-HF is a registry and performance-improvement programme for patients hospitalized with heart failure and includes a subgroup with 60–90 day follow-up data. The relationship between admission serum sodium concentration and clinical outcomes was analysed in 48 612 patients from 259 hospitals. Admission serum sodium levels were analysed both as a continuous variable and by grouping patients with admission Na