Idiopathic primary hyperaldosteronism frequently undergoes spontaneous remission: frequence and predictors

B. Lucatello; A. Benso; I. Tabaro; E. Capello; L. Marafetti; M Parasiliti Caprino; D. Rossato; S. Oleandri; E. Ghigo; M. Maccario

Background: Idiopathic primary hyperaldosteronism (IHA) is the subtype of primary aldosteronism (PA) in which lateralization of the mineralocorticoid hypersecretion cannot be demonstrated. Scanty data are available on the clinical history of IHA: a couple of brief reports suggest a remission of aldosterone hypersecretion after years of treatment with mineralocorticoid receptor blocking agents.

Aim of this study was to check the persistence/remission of aldosterone hypersecretion in patients with IHA followed in a tertiary care referral center for endocrine and metabolic diseases, long after the diagnosis, looking for possible associations of persistence/remission with clinical features.

Patients/Methods: Plasma aldosterone to renin acivity ratio (ARR) and plasma aldosterone after saline infusion test, clinical and metabolic features, indices of early target organ damage, adrenal imaging were obtained in 34 patients followed for 8.4 (range 3–15) years after the diagnosis of IHA. All hormonal measurements were carried out after prolonged (30–40 days) withdrawn of both interfering drugs and low salt diet. Criteria for persistence of PA were the same as at the diagnosis: ARR (pg/ml to ng/ml/h) >400, plasma aldosterone concentration >150 pg/ml basally and >100 pg/ml after saline infusion.

Results: In 26/34 patients (76%) PA was not confirmed. At univariate analysis, remission from PA was positively associated with female sex, potassium levels, age over 60, duration of hypertension and duration of follow-up. Absence of unilateral adrenal mass, treatment with mineralocorticoid antagonists and lower aldosterone levels at diagnosis were not associated to remission. At multivariate analysis, age above 60 years was the only independent predictor of remission of PA (OR 64.7, CI 1.1–3758.9, P=0.044).

Conclusions: This study suggests that mineralocorticoid function in patients with IHA normalize spontaneously at a high rate. Age is a positive predictor of this evenience.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.

Endocrine Abstracts

P73