The Diagnostic Performance of 24-hour Urinary Aldosterone for Primary Aldosteronism

This is an observational study to define the cut-off value of 24-hour urinary aldosterone for diagnosing primary aldosteronism in hypertensive patients in our center. Plasma aldosterone and renin measurements are subject to significant intra-individual variability, including variation related to posture, time of day and sodium balance. Aldosterone secretion is not constant and may be subject to diurnal variation. As such one-off testing of ARR, does not consider the salt status of the individual necessitating repetition of tests to ensure false negative or false positive test results are ruled out. The value of accumulated aldosterone in a 24-hour sample has the advantage that it does not depend on circadian variation. This study will help establish the positivity rates of 24-hour urine aldosterone, and test the robustness of current standard guidelines for primary aldosteronism screening and case confirmation.

Previous studies reported that primary aldosteronism is associated with a higher risk of CV complications and a higher prevalence of target organ damage. Also, previous studies reported on the association of echocardiographic parameters with circulating or urinary aldosterone. Therefore, we intent to investigate the independent associations of different target organ damage with the urinary excretion of aldosterone.