An open model cross sectional observational study of hyponatremic patients in a tertiary care hospital

Harsha Gopinath, T. Duraickannu, Roopak Mohan, G. Rakesh Kumar


Background: Hyponatremia is the most common electrolyte disturbance encountered in clinical practice. Hyponatremia frequently develops in hospitalized patients, especially in metabolic encephalopathy patients, their causes are multiple. Symptomatology depends more on the rate of development of the electrolyte abnormality than on its severity. We undertook this study to determine etiological, clinico-lab profile and differential diagnosis in a group of hyponatremic patients.

Methods: We included retrospectively 50 patients of hyponatremia admitted in medical intensive care unit between June 2013 and May 2014. We excluded all patients who presented with chronic hyponatremia, chronic use of diuretics and recent cases undergoing surgery and chronic cases of malnutrition and those with age below 18 years. Data were analyzed by univariate methods, followed by multivariate analysis.

Results:  Among the 50 patients with hyponatremia, 42% of encephalopathy patients had metabolic encephalopathy. Majority who developed hyponatremia had age between 61 to 80 years. Clinical profile of patients with hyponatremia was revealed that most of the patients with hyponatremia were observed having confusion followed by nausea/vomiting, delirium, seizure. The most common etiology of metabolic encephalopathy with hyponatremia is diuretic induced, followed by diabetic ketoacidosis, chronic liver disease, chronic kidney disease, SIADH and hypothyroidism. The common co-morbid conditions for hyponatremia were hypertension 55.93%, diabetes mellitus 43.85%, and chronic renal failure 35.29%. In the patients with hyponatremia high urine sodium level suggests that most of the patients had hyponatremia due to renal loss of sodium other than extra renal cause.

Conclusions: In the present study, hypertension was found a major risk factor for hyponatremia. Common causes of hyponatremia found are intake of diuretics and excessive renal loss. Most of the hypertensive patients in the present study group were on thiazide or potassium sparing diuretics. Diabetes mellitus and dyslipidemia were important co-morbidities of hyponatremia.



Hyponatremia, Metabolic encephalopathy, Hypertension, Diabetes mellitus, Dyslipidemia

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