Background: Hyponatremia is a common electrolyte disturbance in the hospitalized elderly sick patients. There is no existing record for profiling of symptomatic hyponatremia in elderly Indian subjects.

Objective: To study clinical features and etiology of hyponatremia in elderly hospitalized patients. To classify severity of hyponatremia in hospitalized elderly

Methods: All elderly patients admitted to ICU with serum sodium level < =125 mmol/L were included in study.

Results: 100 patients with symptomatic hyponatremia (serum sodium < =125 mmol/L) were studied. The CNS symptoms included drowsiness, lethargy, confusion, seizures and coma. There was female preponderance of cases (55%). The common co-morbid conditions were Hypertension (69%) and diabetes mellitus (51%). Females tolerated hyponatremia better than males with mortality of 9.09% in females and 33.33% in males (p = 0.0026). The common cause of Hyponatremia was SIADH (30) followed by drugs of which diuretics was the major contributor.

Conclusions: Hyponatremia was more common in females and they seemed to better tolerate it than their male counterparts. Diuretics should be used with caution in elderly.