Endocrine Abstracts

Background: Hyponatremia (HN) is the most common electrolyte disorder of hospitalized patients. It occurs in up to 28% of in-patients, is more common in the elderly and patients with multiple co-morbidities, increases the in-hospital risk of death by 1.47-fold, and is associated with significantly higher mortality risk following discharge. The HN Registry is the first large-scale, international effort to document the clinical characteristics, choice of therapies, and impact of HN in the hospital setting.

Methods: After informed consent or waiver, medical records of patients meeting the registry entry criteria, principally age >18 years and euvolemic or hypervolemic HN (serum sodium ((Na⁺)) <130 mmol/l) were abstracted. Accrual to date is ~59% of the projected enrollment of 3500 patients. Data are summarized by sample size (n) and percentage (%) for categorical data, and mean and standard deviation for continuous data.

Results: A total of 812 of the 2051 patients enrolled at 215 (US=143, EU=72) sites between study initiation in September 2010 and December 2011 had sufficient data for analysis. The mean entry and discharge (Na⁺) values were 126.8±7.3 and 131.8±5.0 mmol/l respectively for all patients and 125.9±7.6 and 132.1±4.6 mmol/l respectively for SIADH patients. Additional results are below.

Conclusions: These interim data suggest that initiation of tolvaptan therapy is delayed and often used as therapy after fluid restriction or saline has failed. Hypertonic saline had the highest response rate but was associated with a greater risk of overly rapid correction (>12 mmol/l in 24 h) than other therapies. Some patients received multiple therapies and are therefore represented in multiple categories, limiting between group interpretations. Additional data, including results for other pharmacologic therapies, will be reported as sufficient data becomes available for meaningful analysis. An adjudication process will be performed to eliminate patients inadvertently enrolled with hypovolemic HN.

Results:

Declaration of interest: I fully declare a conflict of interest. Details below:

Funding: This work was supported, however funding details unavailable.