Hyponatremia in Cirrhotic Patients Often Goes Untreated

Hospitalized patients with cirrhosis who also have hyponatremia often receive no treatment, or ineffective treatment, and are often discharged with their serum sodium too low, according to a study presented here at The Liver Meeting, the 63^rd Annual Meeting of the American Association for the Study of Liver Diseases (AASLD).

Preliminary data from the Global Hyponatremia Registry indicates that 21% of patients were untreated, and 53% of patients were discharged with serum sodium still below 130 mEq/L.

The registry is likely to become the largest database on hyponatremia by the time it reaches its goal of enrolling 5,000 patients. There are currently 4,000 patients enrolled. The registry records data on current medical status and prior admissions, but is not meant to follow patients prospectively.

Of the enrolled patients, 453 (16%) of analyzable patients, had euvolemic or hypovolemic hyponatremia and cirrhosis at the time of hospitalization. The majority were men, with a mean age of 57 years and a mean serum sodium of 124.9 mEq/L.

Twenty-one percent of patients received no treatment for hyponatremia, despite having low sodium. Thirty-eight percent received fluid restriction only, 9% received normal saline only, and 3% received pharmacological treatment only. Of those who received pharmacological monotherapy, the majority were treated with tolvaptan, manufactured by Otsuka Pharmaceuticals, which sponsored the study.

The median hospital stay was lowest for those treated with tolvaptan (three days), followed by other pharmacological therapy or fluid restriction or no treatment (four days), followed by normal saline (six days). Patients on tolvaptan tended to have lower baseline sodium levels than those receiving other treatments.

Patients receiving no treatment had a greater mean increase in serum sodium than those receiving fluid restriction alone (3.7 vs. 3.1 mEq/L) and serum sodium at discharge was higher in patients receiving no therapy (131.2 mEq/L) than in those receiving fluid restriction (129.7 mEq/L).

“The most common therapy for hyponatremia was fluid restriction, and was no more effective than no treatment,” said lead author Samuel Sigal, MD, of New York University.

He also noted that many patients admitted for hyponatremia are treated by hospitalists or primary care physicians, not by specialists who may be more familiar with hyponatremia management.

The goal of the registry, he said, was to collect data to allow a careful analysis of treatment trends. Future studies will examine the clinical impact of correcting sodium more rigorously than is currently the practice, as revealed by these data.