Impact of Hospital-Associated Hyponatremia on Selected Outcomes

Abstract

Hospital-associated hyponatremia is a common occurrence. All forms of hyponatremia are independently associated with in-hospital mortality and heightened resource consumption.

Evaluation of incremental healthcare resource burden and readmission rates associated with hospitalized hyponatremic patients in the US

“…6 In the study by Wald et al, which defined hyponatremia as <138 mEq/L, the risk of in-hospital mortality was similar. 3 In both of these studies, even mild hyponatremia (130-137 mEq/L) was associated with increased risk of in-hospital mortality. 3,6 The overall cost of hyponatremia is estimated to range between $1.6 and $3.6 billion for 2011.…”

“…3 In both of these studies, even mild hyponatremia (130-137 mEq/L) was associated with increased risk of in-hospital mortality. 3,6 The overall cost of hyponatremia is estimated to range between $1.6 and $3.6 billion for 2011. 12,13 Hospital readmissions are a significant contributor to total healthcare costs, with some being entirely avoidable with increased standards of care.…”

“…Hyponatremia is an electrolyte disorder most commonly defined as a serum sodium concentration <135 mEq/ L. 1 Its exact definition can vary across studies, but typically ranges between <130 and <138 mEq/L. 2,3 Signs and symptoms of hyponatremia can include malaise, headache, disorientation, confusion, muscle weakness, and cramps. If severe, seizures, respiratory arrest, brainstem herniation, coma, and death may result.…”

“…6 A recent study reported that when hyponatremia was defined with a less stringent threshold of <138 mEq/L, the incidence at admission rose to 38%. 3 Hyponatremia is a comorbid condition of multiple diseases, occurring in approximately 20% of patients with heart failure, 7,8 and 40% to 57% of patients with advanced cirrhosis. 9,10 The syndrome of the inappropriate release of antidiuretic hormone (SIADH) is additionally a predominant cause of hyponatremia, with a prevalence reported as high as 35% in hospitalized patients.…”

“…The analysis accounted for potential confounding factors by inclusion of the following covariates: age group, gender, race, admission source, and DeyoCharlson Comorbidity Index score. These covariates were previously identified in the Wald et al hyponatremia study, 3 and were verified using likelihood-ratio, Hosmer-Lemshow goodness of fit, and concordance c statistics.…”