Risk factors and mortality in elderly patients with severe hyponatremia admitted to the emergency department

Background This study was aimed at determining the risk factors associated with mortality in elderly patients with severe hyponatremia admitted to the emergency department. Materials and methods The data of patients aged >= 65 years who were admitted to the emergency department and whose serum sodium levels were < 125 mEq/L were retrospectively collected. Results Mortality was associated with chronic liver disease/cirrhosis (p = 0.036), metastatic tumor (p = 0.007) and solid tumor (p = 0.013) cancers, antiarrhythmic drug use (p = 0.003), potassium-sparing diuretic use (p = 0.044), antineoplastic drug use (p = 0.0029), and dialysis treatment (p = 0.015). The following cutoff values were determined to be predictive of mortality: urea > 63.6 (AUC: 0.771; p = 0.0001), creatinine > 1.39 (AUC: 0.675; p = 0.0003), potassium > 4.64 (AUC: 0.711; p = 0.0001), C-reactive protein > 44 (AUC: 0.765; p = 0.0001), white blood cell count > 12.21 (AUC: 0.688; p = 0.0001), hemoglobin < 11.2 (AUC: 0.611; p = 0.0103), and Charlson comorbidity index > 2 (AUC: 0.739; p = 0.0001). The use of antineoplastic drugs (OR: 4.502; p = 0.010) and increased values of the following were associated with an increased risk of mortality: urea (OR: 1.007; p = 0.024), C-reactive protein (OR: 1.005; p = 0.026), glucose (OR: 1.008; p = 0.001), and Charlson comorbidity index (OR: 1.198; p = 0.025). Conclusion Malignancy; liver cirrhosis; dialysis treatment; increased Charlson comorbidity index, urea, and C-reactive protein values and the use of antineoplastic drugs are associated with mortality.

Automated summary

Chronic liver disease/cirrhosis, metastatic and solid tumors, use of antiarrhythmic and potassium-sparing diuretic drugs, antineoplastic drug use, and dialysis treatment are associated with mortality risk in elderly patients with severe hyponatremia.