Clinical Manifestations of Elderly Patients Admitted Because of Severe Hyponatremia

Oh, You Jeong; Han, Ji Sun; Kim, Do Kyong; Chung, Seuk Hee; Kim, Sang Ock; Hsing, Chien Ter; Mok, Ji Young; An, Won Suk; Kim, Seong Eun; Kim, Ki Hyun

Abstract

PURPOSE
Recently the incidence of severe hyponatremia is increasing in old patients but there is no report about clinical findings of old patients with hyponatremia. We evaluated the cause and clinical manifestations of severe hyponatremia in old patients who had been admitted via emergency room.
METHODS
We retrospectively reviewed clinical records of the hyponatremic patients who had been admitted from 2000 to 2007. We enrolled 53 patients (Age >60 years, Na <125 mEq/L) without severe liver cirrhosis, heart failure or chronic kidney disease. We analyzed data to evaluate the differences of clinical manifestations according to the presence of symptoms, taking diuretics, urine sodium concentrations and the degree of hyponatremia.
RESULTS
Mean serum sodium concentration was 111.4+/-6.9 mEq/L and urine sodium concentration was 68.7+/-43.8 mEq/L. There was no difference in serum sodium concentration according to age. Twenty-nine (54.7%) patients had nausea and vomiting and 19 patients (35.8%) had neurologic symptoms. Patients with neurologic symptoms showed lower serum and urine sodium concentration than patients without neurologic symptoms. The main causes of severe hyponatremia were poor oral intake (79.2%), diuretics use (37.7%) and recent operation (15.1%). The mean sodium concentration of the fluid administered to achieve 125 mEq/L of serum sodium level was 336.5+/-160.6 mEq/L.
CONCLUSION
The urinary sodium loss, e.g., diuretics abuse, may be the main cause of severe hyponatremia in elderly patients over 60 years. In elderly patients, diuretics should be carefully administered with frequent electrolyte monitoring.