Antidepressant-associated hyponatremia among the elderly: A retrospective study

Background: The use of antidepressants among elderly is associated with dreaded side effect of hyponatremia. However, there is limited information about specific risk factors associated with developing hyponatremia in elderly. Aim of the Study: The aim of this study was to evaluate the clinical risk factors for the development of hyponatremia among elderly patients started on antidepressant medications. Methodology: Using retrospective study design, patients who developed hyponatremia (n = 35) and those who did not develop hyponatremia (n = 43) with use of antidepressants, were matched on sociodemographic parameters and were compared for various parameters such as physical illness, other medications, and dose and type of antidepressant drug. Results: Higher proportion of those who developed hyponatremia had history of comorbid hypertension, were receiving antihypertensive agents, and were receiving 2 antihypoglycemic agents concomitantly. Majority of the patients who developed hyponatremia were receiving mirtazapine, followed by sertraline and venlafaxine. There was no association of hyponatremia with concomitant use of psychotropics, presence of other physical illnesses, comorbid dementia, and comorbid substance use. Conclusion: Antidepressant-associated hyponatremia is more commonly seen in patients with comorbid hypertension, those receiving any antihypertensive agent and those on more than one hypoglycemic agent.