Low-renin primary aldosteronism predicts superior surgical outcomes compared to high-renin disease.

OBJECTIVE: To study the prognostic difference of unilateral adrenalectomy in patients with Primary Aldosteronism (PA) with different renin levels. METHODS: The clinical data of 159 patients with PA who underwent unilateral adrenalectomy at Beijing Anzhen Hospital of Capital Medical University from August 2022 to January 2025 were retrospectively analyzed. The mean age of the 159 patients was 51.98 ± 10.61 years old, the body mass index was 26.10 ± 3.94 kg/m2, and the preoperative glomerular filtration rate was 88.53 ± 20.30 ml/(min*1.73m2), preoperative serum creatinine 81.83 ± 27.66 µmol/L. The expression of aldosterone synthase in adrenal specimens was detected postoperatively and staged according to the 2022 World Health Organization Consensus on Histopathology of PA. The 159 patients with PA were divided into low and high renin groups according to the lower limit of the reference range of renin level of 4.4 µIU/ml in our institution, respectively. Both clinical success and biochemical success including complete, partial and no success were assessed with reference to the 2016 Consensus on Prognostic Evaluation of PA Surgery Comparison. The prognosis of different aldosterone level groups was compared using non-parametric tests. RESULTS: There were 121 cases in the low renin group, of which 87 cases (71.90%) were completely successful clinically, 32 cases (26.45%) were partially successful, and 2 cases (1.65%) were no success; 102 cases (84.20%) were completely successful biochemically, 8 cases (6.61%) were partially successful, and 11 cases (9.09%) were no success. In the high renin group, there were 38 cases, of which 19 cases (50.00%) were completely successful clinically, 15 cases (39.47%) were partially successful, and 4 cases (10.53%) were no success; 26 cases (68.42%) were completely successful biochemically, 7 cases (18.42%) were partially successful, and 5 cases (13.16%) were no success. The clinical prognosis (P = 0.011) and biochemical prognosis (P = 0.045) of PA patients in the low renin group were significantly different from those in the high renin group. A total of 101 out of 159 PA patients underwent adjunctive aldosterone synthase testing of postoperative adrenal specimens. There were 44 cases of Aldosterone-Producing Adenomas (APA), 1 case of Aldosterone-Producing Nodule (APN), Aldosterone-Producing Micronodules (APM) 5, Multiple Aldosterone-Producing Nodules (MAPN) 1, Multiple Aldosterone-Producing Micronodules (MAPM) 9, Aldosterone Producing Diffuse Hyperplasia (APDH) 4, all-negative 3 and mixed 19 in low renin group; and in high renin group, there are 7 cases of APA, 1 case of APM, 1 case of MAPN, 4 cases of MAPM, APDH 1 case, and mixed 1 case. CONCLUSION: The prognosis of PA patients in the low renin group who underwent unilateral adrenalectomy was better than that of PA patients in the high renin group.