Hyponatremia prolongs hospital stay and hypernatremia better predicts mortality than hyponatremia in hospitalized patients with community-acquired pneumonia

INTRODUCTION: Dysnatremia is reported to have a prognostic effect in various diseases. A limited number of studies have been published on dysnatremiarelated parameters and clinical outcome in patients with pneumonia. The aim of the study is to analyze the factors related to baseline dysnatremia and to evaluate the clinical outcome of dysnatremia on hospital stay, 30-day and 1-year mortality in hospitalized patients with community-acquired pneumonia (CAP). MATERIALS AND METHODS: The study is a two-centre, retrospective, crosssectional study. According to the baseline corrected sodium values, hospitalized patients with CAP were grouped as hyponatremia (<135 mmol/L), normonatremia (135-145 mmol/L) and hypernatremia (> 145 mmol/L). RESULT: Of all the 471 patients included, 119 (25.3%) had hyponatremia and 25 (5.3%) had hypernatremia. Higher leucocytes and lower albumin values correlated with hyponatremia while female gender, higher leucocytes and urea levels correlated with hypernatremia. Baseline hyponatremia prolonged hospital stay (9.2 ± 5.6, vs. 7.5 ± 4.6, respectively, p= 0.001) and increased 1-year mortality. On the other hand, hypernatremia predicted 30-day (40%, vs. 10%, p<0.001) and independently predicted 1-year mortality (p< 0.001). CONCLUSIONS: In hospitalized patients with CAP, baseline hyponatremia prolongs hospital stay while hypernatremia signals a worse outcome both in the short term and long term.