Prognostic factors of primary aldosteronism

Primary aldosteronism (PA) is a rare but potentially curable cause of hypertension. Between October 1982 and November 1994, 30 patients of PA received unilateral adrenalectomy with a long-term follow up (mean:60.3 months). Nineteen (63.3%) cases were cured (Group 1); 11(36.7%) cases were improved (Group 2). The purpose of this study was to determine prognostic factors after surgery in patients with PA.

A retrospective analysis was performed regarding age and sex of the patients, duration of hypertension, family history of hypertension, preoperative blood pressure, plasma aldosterone concentration (PAC), plasma renin activity (PRA) and efficacy of spironolactone on blood pressure between both groups. End-organs (including kidney, heart, retina and brain) involvement was evaluated and compared. Adrenalectomy and renal biopsy specimen for pathology were similarly evaluated.

The duration of hypertension was longer in Group 2 than in Group 1 (8.18 +/- 4.94 vs 5.21 +/- 4.24 years). The efficacy of spironolactone on blood pressure (BP) was positive in 81.8% of Group 1 and 16.7% of Group 2. Adrenal cortical adenoma in 24 cases with a cure rate of 70.8% (17/24) and adrenal cortical macronodular hyperplasia in 6 cases with a cure rate of 33.3% (2/6) were noted. Group 2 had more end-organs involvement than Group 1. The severity of histopathological change of the renal biopsy was similar.

This study suggests that preoperative response of blood pressure to spironolactone administration predicts the postoperative prognosis of hypertension in patient with PA. Long duration of hypertension and involvement of two or more end-organs were poor prognostic factors. Excellent results can be achieved by unilateral adrenalectomy in adrenal cortical adenoma and fair results, in adrenal cortical macronodular hyperplasia.