Comparison of eplerenone and spironolactone for the treatment of primary aldosteronism.

The mineralocorticoid receptor (MR) is expressed in the kidneys and in adipose tissue, and primary aldosteronism (PA) is associated with metabolic syndrome. This study assessed the effects of MR blockade by eplerenone (EPL) and spironolactone (SPL) on blood pressure (BP) and metabolic factors in patients with PA. Fifty-four patients with PA were treated with one of two MRAs, EPL (25-100 mg daily, n=27) or SPL (12.5-100 mg daily, n=27) for 12 months. Visceral (VAT) and subcutaneous adipose tissue were quantified using CT and FatScan imaging analysis software. Body mass index, homeostasis model assessment-insulin resistance (HOMA-IR), serum creatinine, potassium and lipids, urinary albumin excretion (UAE) and plasma aldosterone concentration (PAC) and plasma renin activity (PRA) were measured before and after treatment. EPL and SPL decreased BP and increased serum potassium levels to similar degrees. PAC and PRA did not differ between the two groups. Although treatment with the MRAs did not change HOMA-IR or serum lipids, they significantly decreased UAE and VAT (P<0.05). These results suggest that EPL and SPL are effective and safe for the treatment of PA. The long-term metabolic and renal effects of these MRAs should be further investigated.