Persistent Renin Suppression After Unilateral Adrenalectomy for Primary Aldosteronism: Implications for Adverse Outcome?

Abstract

Suppressed renin concentrations in medically treated patients with primary aldosteronism (PA) are associated with a worse cardiometabolic outcome compared to patients with normalized renin levels. No similar study has been conducted in patients with PA after unilateral adrenalectomy. This study investigates the prevalence and impact of persistent renin suppression after unilateral adrenalectomy in patients with lateralized PA. We retrospectively included 77 patients who underwent adrenalectomy for lateralized PA. All patients had postoperative renin levels available. Patients were divided into tertiles based on their direct renin concentrations (DRC) (<8 mU/L, 8-16 mU/L, >16 mU/L) at the first follow-up, approximately 6 months after surgery. Study endpoints included histopathology using CYP11B2 staining according to HISTALDO consensus, biochemical and clinical outcomes according to the PASO criteria and improvement of comorbidities and end-organ damage at short- and long-term follow-up up to 3 years postoperatively. Patients with DRC <8 mU/L showed a higher prevalence of non-classical histopathology compared to the other 2 tertiles (8/26 [30.8%] vs 1/25 [4%] vs 3/26 [11.5%]; P = .024) and more frequently absent or partial biochemical remission at their first follow-up (9/26 [34.6%] vs 3/25 [12.0%] vs 2/26 [7.7%]; P = .036). Nonetheless, 65.4% achieved complete biochemical remission. Clinical outcomes, including end-organ damage and comorbidities, did not differ across the tertiles. Persistent renin suppression is common 6 months after adrenalectomy and associated with worse biochemical but not clinical outcomes. More than 60% of patients with DRC <8 mU/L achieved full biochemical remission.