Significance of Hyponatremia as an Independent Factor in Predicting Short-term Mortality in Patients with Hemorrhagic Stroke

Introduction Hyponatremia is the most common electrolyte imbalance in patients with acute cerebrovascular insults. In patients with acute non-traumatic hemorrhagic stroke, the role of hyponatremia as a negative prognostic indicator has been controversial. The aim of this study is to evaluate the frequency of hyponatremia in patients with hemorrhagic stroke and determine its impact on their in-hospital disease outcome. Methods This was a prospective observational study, which included all patients with non-traumatic hemorrhagic stroke. Serum sodium concentration <135 mmol/L was labeled as hyponatremia. The etiology of hyponatremia was determined as syndrome of inappropriate antidiuretic hormone (SIADH) and cerebral salt wasting syndrome (CSWS). The outcome was categorized as “complete recovery,” “motor/sensory deficit but not wheelchair/bed bound,” “wheelchair/bed bound,” and “in-hospital mortality.” SPSS for Windows version 22.0 (IBM Corp., Armonk, NY, US) was used to analyze the data. Results Out of 234 patients of hemorrhagic stroke, 45.3% (n=106) were hyponatremic, 58.5% had SIADH and 41.5% had CSWS. The overall mortality rate of hemorrhagic stroke was 16.2%. The mortality rate was 36.5% in the SIADH group, 50% in the CSWS group, and 13.1% in the normonatremic group (p<0.00001). The mean hospital stay in the SIADH group was 7.04 ± 2.57, in the CSWS group, it was 6.50 ± 1.55, and in the normonatremic group, it was 3.88 ± 2.74 (p=0.000). Conclusion Hyponatremia is an independent predictor of short-term mortality in patients with acute hemorrhagic stroke.