Appropriate Timing for a Biochemical Evaluation After Adrenalectomy for Unilateral Aldosterone-Producing Adenoma

Kimiharu Takamatsu; Toshikazu Takeda; Seiya Hattori; Nobuyuki Tanaka; Shinya Morita; Kazuhiro Matsumoto; Takeo Kosaka; Ryuichi Mizuno; Toshiaki Shinojima; Eiji Kikuchi; Hiroshi Asanuma; Isao Kurihara; Hiroshi Itoh; Mototsugu Oya


Clin Endocrinol. 2020;92(6):503-508. 

In This Article

Abstract and Introduction


Context: The oversecretion of plasma aldosterone by unilateral aldosterone-producing adenoma (APA) can be cured by adrenalectomy. However, the time needed for the endocrine environment to normalize remains unclear.

Objective: To clarify adequate timing for a biochemical evaluation in unilateral APA patients after adrenalectomy.

Design and patients: A total of 166 unilateral APA patients were retrospectively reviewed. We evaluated the plasma aldosterone concentration (PAC) (pg/mL), active renin concentration (ARC) (pg/mL), aldosterone-renin ratio (ARR; PAC/ARC), serum potassium concentration and estimated glomerular filtration rate (eGFR) at 1, 3 and 6 postoperation months (POM).

Results: PAC was significantly lower at 1POM than at presurgery (presurgery; 407.2, 1 POM; 90.0 pg/mL, P < .001). ARC did not increase from baseline at 1POM, but significantly increased at 3POM (presurgery; 4.43, 1POM; 4.87, 3POM; 11.3 pg/mL, P < .001). ARR significantly decreased at 1POM (presurgery; 146.9, 1 POM; 26.3, P < .001) although ARC did not increase at 1POM. Among the 34 patients who had hypokalaemia presurgery, it was resolved in 28 (82%) at 1POM and in all (100%) at 3POM. The biochemical outcomes at 1POM were 131 (79%) complete, 20 (12%) partial and 15 (9%) absent successes, while at 3POM, 147 (89%) were complete, 9 (5%) partial and 10 (6%) absent. Twenty-three (14%) patients were reclassified into different biochemical outcomes between 1 and 3POM, whereas only 5 (3%) changed between 3 and 6POM.

Conclusion: The appropriate timing for a biochemical evaluation of unilateral APA patients treated with laparoscopic adrenalectomy appears to be 3 months or more after surgery.


Primary aldosteronism (PA) is an endocrine disease characterized by high plasma aldosterone and suppressed plasma renin levels.[1] PA is a common cause of endocrine hypertension, with an estimated prevalence of between 5% and 11% in patients with arterial hypertension.[2–4] The presence of PA has been identified as an independent risk factor for cardiovascular events in hypertensive patients.[1,2,5] PA has been classified as both a unilateral and bilateral diseases. The recommended treatment for unilateral PA, which includes aldosterone-producing adenoma (APA) and unilateral adrenal hyperplasia (UAH), is laparoscopic adrenalectomy because it is curable by surgical excision.[1] The surgical outcomes of adrenalectomy for unilateral PA are evaluated based on clinical and biochemical success. The clinical evaluation focuses on blood pressure and the use of antihypertensive medication. However, in a multicenter study, the proportion of patients achieving clinical success varied widely (17%-62%) because hypertensive patients were likely to have other internal causes and the use of antihypertensive drugs depended on the attending physicians.[6] A biochemical evaluation (an evaluation of changes in plasma aldosterone concentrations: PAC, the aldosterone-renin ratio: ARR and serum potassium concentrations) was previously reported as an appropriate evaluation tool for surgical outcomes because of the smaller associated disparity.[6]

The oversecretion of plasma aldosterone by unilateral PA needs to be resolved by adrenalectomy; however, the time needed for the endocrine environment to normalize remains unclear. Therefore, we herein evaluated changes in the hormonal environment over time after laparoscopic adrenalectomy for unilateral APA and clarified the adequate timing for a biochemical evaluation.