Predictive factors of hyponatremia in subarachnoid hemorrhage and outcomes

Background & Objective: The prevalence of hyponatremia in subarachnoid hemorrhage (SAH) was 30-55%. There was lack of evidence about predictive factors and clinical outcomes of hyponatremia in SAH patients. This study aimed to evaluate factors associated with hyponatremia following SAH and to review the clinical outcomes and treatment of hyponatremia in SAH patients. Method: This is a retrospective cohort study. SAH patients presented during January 2013 to January 2019 were reviewed. They were divided into 2 groups: SAH with normonatremia and SAH with hyponatremia. Clinical data, laboratory profile, aneurysm characteristics and clinical outcomes were recorded and analyzed. Result: A total number of 278 patients with SAH were included, 139 patients in each group. The populations were female 66% with mean age of 56 years old and mean serum sodium (Na) level 132 mmol/L. Aneurysm location associated with hyponatremia; anterior cerebral artery (ACA) (OR 4.2, 95%CI 1.4-13.0, p-value 0.009) and posterior cerebral artery (PCA) (OR 3.7, 95%CI 1.2-11.5, p-value 0.017). Aneurysms clipping procedure was also associated with hyponatremia (OR 4.0, 95%CI 1.8-8.8, p-value < 0.001). Conclusion: ACA and PCA aneurysms and aneurysms clipping procedure were risk factors for hyponatremia following SAH. Mild hyponatremia was not associated with morbidity and mortality in SAH patients.