Clinical features, outcome and cost of hyponatremiaassociated admission and hospitalization in elderly and very elderly patients: A single-center experience in Turkey

Abstract

Purpose Hyponatremia is a common electrolyte disorder in hospitalized patients. Clinical features, outcome and cost of hyponatremia-associated admission and hospitalization in elderly and very elderly patients are not well known. Methods Elderly (64 years) patients admitted to the emergency department (ED) and hospitalized between January 1, 2010, and December 31, 2010, were evaluated. Hyponatremia was defined as serum sodium level below 135 mmol/L. Hyponatremic patients were divided into two groups: group 1 (n = 150, 65-74 years old) and group 2 (n = 103,74 years old). Results A total of 4,960 patients above 65 years of age admitted to ED and hospitalized were included. Prevalence of ED in group 1 and group 2 was 4.1 % (150/3,651) and 7.8 % (103/1,309), respectively (P<0.001). Vomiting and diarrhea were the most important complaints. A total of 111 (43.8 %) patients were being treated with renin-angiotensin system (RAS) blockers. Mortality, morbidity and hospital cost increased in parallel to decrease in serum Na? level and increase in age. Group 2 subjects had not only higher intensive care need (P<0.01) and mortality rates (P<0.01), but also higher hospital cost burden (P<0.05) compared to group 1. Alzheimer's disease was one of the most common co-morbidity in patients, particularly in group 2 (5.3 % vs. 21.3 %, P<0.001). Conclusion Hyponatremia-associated hospitalization is an important and potentially lethal condition in elderly and very elderly patients. Clinicians should be careful when prescribing RAS blockers and diuretics in elderly patients. © Springer Science+Business Media Dordrecht 2013.