Hyponatraemia: A strong predictor of mortality in adults with congenital heart disease

Area of Science:

• Cardiology
• Internal Medicine
• Clinical Research

Background:

• Adult congenital heart disease (ACHD) represents a growing population with complex medical needs.
• Understanding the prognostic factors in ACHD is crucial for improving patient outcomes.
• Hyponatraemia is a common electrolyte disturbance with known implications in various cardiovascular conditions.

Purpose of the Study:

• To determine the prevalence of hyponatraemia in a large cohort of adult patients with congenital heart disease.
• To investigate the prognostic significance of hyponatraemia on mortality in the ACHD population.
• To identify predictors associated with hyponatraemia in ACHD patients.

Main Methods:

• Retrospective analysis of 1004 adult congenital heart disease patients.
• Assessment of hyponatraemia prevalence and associated clinical factors.
• Cox regression analysis, multivariable regression, and propensity score matching to evaluate mortality risk associated with hyponatraemia, adjusting for confounders.

Main Results:

• The prevalence of hyponatraemia in the ACHD cohort was 15.5%, with higher rates in specific conditions like congenitally corrected transposition (33.3%) and post-Fontan operation (29.6%).
• Predictors of hyponatraemia included worse functional class, cyanosis, elevated serum creatinine, and diuretic use.
• Hyponatraemia was a significant independent predictor of mortality (adjusted Hazard Ratio 2.82), even after accounting for other risk factors.

Conclusions:

• Hyponatraemia is a prevalent finding in adult congenital heart disease patients.
• Hyponatraemia is associated with a substantially increased risk of death in ACHD, approximately threefold.
• Hyponatraemia serves as a simple, cost-effective, yet potent marker for predicting mortality in ACHD.