Impact of Targeted Hyponatremia Correction on 30-day Mortality and Rehospitalization Rate

Impact of Targeted Hyponatremia Correction on 30-day Mortality

Impact of Targeted Hyponatremia Correction on 30-day Mortality and Rehospitalization Rate

Julie Refardt¹

(1) Erasmus MC, Rotterdam, Netherlands.

Background:

Chronic hyponatremia is associated with increased mortality and rehospitalization rates, but it is unclear whether this association is causal. This leads to uncertainties in correction, which is therefore often slow or absent. The aim of this study was therefore to evaluate the direct effects of targeted hyponatremia correction versus routine care on mortality and rehospitalization rates.

Methods:

Randomized controlled, superiority, parallel-group, international multi-center trial with blinded outcome assessment. Hospitalized participants with hyponatremia <130 mmol/L from nine tertiary centers across Europe were assigned to undergo either targeted correction of plasma sodium levels according to guidelines (intervention) or routine care for hyponatremia (control). The primary outcome was the combined risk of death or rehospitalization within 30 days of study inclusion.

Results:

2174 patients were included in the primary analysis of which 1079 (49.6%) were randomized to the intervention and 1095 (50.4%) to the control group. Through the intervention, 641 (60.4%) patients reached normonatremia, compared to 493 (46.2%) patients in the control group.
Within 30 days, death or rehospitalization occurred in 93 (8.6%) and 138 (13.0%) patients in the intervention group, compared to 93 (8.5%) and 151 (14.0%) patients in the control group, leading to a combined event rate of 21.0% (224/1079 patients) in the intervention group and 22.2% (239/1095 patients) in the control group, estimated absolute difference in proportions [95% CI] -1.2% [-4.7, 2.3], p=0.50. This result was robust in the per protocol analysis and in subgroup analyses considering hyponatremia etiology, severity or correction rate.

Conclusion:

In this large hyponatremia intervention trial, targeted plasma sodium correction did not reduce 30-day mortality and rehospitalization rates. This suggests that in hospitalized patients, chronic hyponatremia is a marker of disease severity rather than a cause of worse outcome.