Variability of aldosterone, renin and the aldosterone-to-renin ratio in hypertensive patients without primary aldosteronism

Abstract

Objectives: The aldosterone-to-renin ratio (ARR) is commonly used in the screening of primary aldosteronism. However, limited information is available with regard to the intra-patient variability in this ratio. Our objective is to determine whether ARR measurements are reliably consistent over both the short-and long-term. Methods:We assessed the short-term variability of the aldosterone-to-renin ratio in 116 unmedicated, essential hypertensive participants who had two blood samples taken in the morning of the same day for measurement of aldosterone and active plasma renin concentration. Longterm variability was studied in 22 unmedicated, essential hypertensive participants who had two blood samples taken approximately 1 year apart. All samples were taken under highly standardized conditions.Results: Our data show that renin, aldosterone and the aldosterone-to-renin ratio show marked variations, both when measured on the same day and when assessed at a longer interval. The ARR becomes increasingly variable as its mean value increases. Its degree of variability is similar in both the short-term and the long-term.Conclusions: Based on our findings, we conclude that the aldosterone-to-renin has acceptable short-term variability in the lower ranges, but increasingly dubious reliability as aldosterone-to-renin values rise. Thus, in a clinical context, great caution should be taken in interpreting pointmeasurements of moderate to high aldosterone-to-renin ratio values.

Long-Term Follow-Up of Patients With Elevated Aldosterone-to-Renin Ratio but Negative Confirmatory Test: The Progression of Primary Aldosteronism Phenotypes

“…It should be noted that, in 23% of the patients, renin levels were no longer suppressed at follow-up and about half of the patients had a negative screening test at the second visit. This is not surprising, considering the renin variability that is observed in patients without PA, 26 justified by several factors, in particular dietary sodium intake. 27,28 However, at least in our study, dietary sodium intake estimated by 24-hour urinary sodium excretion was unaltered at follow-up.…”

Diagnosis and management of primary hyperaldosteronism in patients with hypertension: a practical approach endorsed by the British and Irish Hypertension Society

“…In well controlled conditions, an elevated ARR had a relatively good sensitivity for diagnosing PA [ 1 ] and, as such, is widely used for screening. Several authors have however questions its reliability due to significant variation on repeated measurements [ 44 ] and it is now commonly accepted that the interpretation of the ARR is subject to several pitfalls [ 45 ]. In fact, ARR is influenced by electrolyte abnormalities, drugs [ 1 ], circadian rhythm [ 46 ] and posture.…”