Incidence of Hyponatremia in Geriatric Patients Presenting to the Emergency Department with Headache

Objective: Headache is one of the most common neurological complaints in elderly population. Hyponatremia is a rare condition that can cause headache. The aim of our study was to evaluate the frequency and etiology of hyponatremia in geriatric patients presenting to the emergency department (ED) with atraumatic headache. Methods: This is an observational, retrospective study. Patients aged 65 years and older with serum sodium levels who presented to the ED with headache were included in the study. Demographic data, comorbidities, other admission complaints, medications, and sodium levels were retrospectively reviewed. Results: The study included 429 patients. Hyponatremia was detected in 17.7% (n=76) of the patients and was mostly mild (56.6%). In comparison with normonatremic patients, hyponatremic patients had increased frequency of hypothyroidism and diuretic use, longer hospital stays, higher blood urea nitrogen, and lower serum osmolarity, hemoglobin, and albumin levels (p<0.05 for all values). Conclusion: Our results showed the presence of hyponatremia in a significant proportion of patients presenting to the ED with headache. Most cases of hyponatremia were hypovolemic and was caused by diuretic use, dehydration, and inappropriate antidiuretic hormone syndrome. In patients with comorbidities and polypharmacy, hyponatremia should be prioritized as a potential cause of secondary headache and should contribute to the management of patients in emergency settings.