Abstract
Mild chronic hyponatremia, as defined by a persistent (>72 hours) plasma sodium concentration between 125 and 135 mEq/L without apparent symptoms, is common in ambulatory patients and generally perceived as being inconsequential. The association between increased mortality and hyponatremia in hospitalized patients in various settings and etiologies is widely recognized. This review analyzes the significance of mild chronic hyponatremia in ambulatory subjects and its effects on mortality and morbidity. It addresses whether this disorder should even be treated and if so, which patients are likely to benefit from treatment. The available approaches to correct hyponatremia in such patients in the context of recently published panel-generated recommendations and guidelines are described.