Cost-effectiveness of adrenal vein sampling- vs computed tomography-guided adrenalectomy for unilateral adrenaloma in primary aldosteronism

Purpose Adrenalectomies performed for the treatment of primary aldosteronism due to unilateral adenoma are traditionally confirmed with, and guided by, results from adrenal vein sampling (AVS). However, the usefulness of AVS at the expense of cost and complications is debated, and many institutions have independent protocols that use AVS to varying degrees. Methods Cost-effectiveness of AVS- vs computed tomography (CT)-based adrenalectomy was calculated using decision tree models. The tree was populated with values describing biochemical post-operative outcomes from the published literature; patients were placed into AVS- or CT-dependent treatment arms. Biochemical outcomes were defined based on patients' potassium levels and aldosterone-renin ratios. Patients underwent adrenalectomies and received medical management dosed based on surgical outcomes. Costs were represented by Medicare (FY2021) reimbursement rates (US$) and quality-adjusted life-years (QALYs) were calculated using published morbidity and survival data. A willingness-to-pay of $100,000 per QALY gained was set to determine the most cost-effective strategy. The primary outcome was the incremental cost-effectiveness ratio (ICER) associated with biochemical outcomes. Results The base case analyses favored the use of AVS-guided care, which cost $307.65 more but yielded 0.78 more QALYs, resulting in an ICER of $392.57. These results were upheld by all one-way and two-way sensitivity analyses. In 100,000 random-sampling simulations, AVS-guided care was favored 100% of the time. Conclusions For patients with primary aldosteronism receiving adrenalectomies with curative intent, the more cost-effective method based on biochemical outcomes is AVS-based care. Recent literature suggests biochemical resolution should be favored over clinical resolution, due to long-term detriments of increased aldosterone independent of clinical symptoms.