ACTH Stimulation and Oral Salt Loading Tests Detect Biochemical Outcome Early After Primary Aldosteronism Surgery

Area of Science:

• Endocrinology
• Surgical Outcomes
• Clinical Diagnostics

Background:

• Primary aldosteronism (PA) management relies on assessing aldosterone hypersecretion post-surgery, typically 6-12 months later.
• Predicting early surgical outcomes in PA patients remains an area with limited investigation.
• This study explores the utility of immediate postoperative endocrine testing for outcome prediction.

Purpose of the Study:

• To evaluate the predictive value of the adrenocorticotropin stimulation test (AST) and oral salt loading test (OST) in the early postoperative period.
• To determine if these tests can forecast biochemical outcomes one year after adrenalectomy for PA.
• To compare the efficacy of immediate postoperative tests versus baseline measurements in predicting surgical success.

Main Methods:

• Retrospective analysis of 268 PA patients undergoing adrenalectomy (2008-2020).
• AST and OST were administered within 15 days post-surgery.
• Patients were categorized by biochemical outcomes (complete vs. incomplete success) at one year, with analysis of AST and OST parameters.

Main Results:

• Patients with incomplete biochemical success showed higher baseline and post-test plasma aldosterone concentration (PAC) and PAC/serum cortisol ratio (PAC/Cort).
• Post-ACTH loading PAC/Cort (AUC=0.76) and 24-hour urine aldosterone (AUC=0.77) were identified as superior predictors.
• Post-ACTH loading parameters demonstrated better predictive accuracy for both biochemical and clinical outcomes than baseline values.

Conclusions:

• Adrenocorticotropin stimulation tests (AST) and oral salt loading tests (OST) conducted immediately after surgery are effective predictors of long-term outcomes in primary aldosteronism.
• These early postoperative tests can reliably forecast both biochemical and clinical success one year after adrenalectomy.
• The findings support the use of immediate postoperative endocrine testing for patient management and outcome assessment in PA.