Igor Sturdik1, Monika Adamcova2, Jana Kollerova3, Tomas Koller4, Zuzana Zelinkova5, Juraj Payer6. 1. 5th Department of Internal Medicine, Medical Faculty of Comenius University, University Hospital Bratislava, Slovakia. Electronic address: igor.sturdik@gmail.com. 2. 5th Department of Internal Medicine, Medical Faculty of Comenius University, University Hospital Bratislava, Slovakia. Electronic address: adamcova.monika@gmail.com. 3. 5th Department of Internal Medicine, Medical Faculty of Comenius University, University Hospital Bratislava, Slovakia. Electronic address: jana.kollerova@gmail.com. 4. 5th Department of Internal Medicine, Medical Faculty of Comenius University, University Hospital Bratislava, Slovakia. Electronic address: koller.tomas@gmail.com. 5. 5th Department of Internal Medicine, Medical Faculty of Comenius University, University Hospital Bratislava, Slovakia. Electronic address: zelinkova@ru.unb.sk. 6. 5th Department of Internal Medicine, Medical Faculty of Comenius University, University Hospital Bratislava, Slovakia. Electronic address: payer@ru.unb.sk.
Abstract
BACKGROUND: Hyponatraemia increases morbidity and mortality, but the extent to which this condition influences mortality independently of other contributing factors is unclear. MATERIALS AND METHODS: All hyponatremic patients admitted to the internal medicine department during a six month period were included. Medical records were reviewed and patients' demographics, underlying disease, cause of hyponatremia and in-hospital deaths were noted. Control group consisted of patients with normonatremia admitted to the same department during the same period matched 1:1 by sex, age and underlying disease. Difference in in-hospital mortality rate between the study and control groups was tested by chi-square test. Baseline demographics, underlying diseases, cause of hyponatremia and state of hyponatremia correction as possible risk factors for mortality were tested in a multivariate analysis. RESULTS: The baseline cohort of all admitted patients consisted of 2,171 patients. Hyponatraemia was found in 278 (13%) patients (160 females and 118 males). The three most common causes of hyponatremia included gastrointestinal loss (52 patients), decreased oral intake (47 patients), and dilution hyponatremia (45 patients). The in-hospital mortality rate in the hyponatremic group was significantly higher compared with the control group (22% vs 7%, respectively; OR 3.75, 95% CI 2.17-6.48, p<0.0001). In a multivariate analysis age above 65 years, dilution hyponatremia, decreased oral intake as etiologic factors of hyponatremia, and unsuccessful hyponatremia correction were independent factors associated with increased mortality. CONCLUSION: Hyponatraemia represents independent factor associated with in-hospital mortality. Age above 65 years, failure to correct hyponatremia and some specific etiologic factors of hyponatremia are related to increased mortality.
BACKGROUND:Hyponatraemia increases morbidity and mortality, but the extent to which this condition influences mortality independently of other contributing factors is unclear. MATERIALS AND METHODS: All hyponatremic patients admitted to the internal medicine department during a six month period were included. Medical records were reviewed and patients' demographics, underlying disease, cause of hyponatremia and in-hospital deaths were noted. Control group consisted of patients with normonatremia admitted to the same department during the same period matched 1:1 by sex, age and underlying disease. Difference in in-hospital mortality rate between the study and control groups was tested by chi-square test. Baseline demographics, underlying diseases, cause of hyponatremia and state of hyponatremia correction as possible risk factors for mortality were tested in a multivariate analysis. RESULTS: The baseline cohort of all admitted patients consisted of 2,171 patients. Hyponatraemia was found in 278 (13%) patients (160 females and 118 males). The three most common causes of hyponatremia included gastrointestinal loss (52 patients), decreased oral intake (47 patients), and dilution hyponatremia (45 patients). The in-hospital mortality rate in the hyponatremic group was significantly higher compared with the control group (22% vs 7%, respectively; OR 3.75, 95% CI 2.17-6.48, p<0.0001). In a multivariate analysis age above 65 years, dilution hyponatremia, decreased oral intake as etiologic factors of hyponatremia, and unsuccessful hyponatremia correction were independent factors associated with increased mortality. CONCLUSION: Hyponatraemia represents independent factor associated with in-hospital mortality. Age above 65 years, failure to correct hyponatremia and some specific etiologic factors of hyponatremia are related to increased mortality.