The aim of the present study was to compare the effects of the aldosterone blocker eplerenone and thiazide-like diuretic indapamide on blood pressure (BP) and target organs with reference to salt intake in hypertensive outpatients. Twenty hypertensive patients (nine women and 11 men, mean age 71 ± 13 years) with inadequate BP control despite taking calcium channel blockers (CCBs) and angiotensin II receptor blockers (ARBs) were administered eplerenone (50 mg/day) or indapamide (1 mg/day) for 3 months each in a randomized crossover manner. Salt intake, BP and indices of organ damage were assessed at baseline and at the end of each treatment period. Eplerenone and indapamide were similarly effective in lowering office and home BPs. Both the treatments significantly reduced the estimated glomerular filtration rate (eGFR) and increased serum uric acid levels. The treatment with eplerenone significantly increased serum potassium levels, whereas the treatment with indapamide significantly decreased them. The treatment with eplerenone significantly decreased pulse wave velocity and urinary 8-hydroxydeoxyguanosine levels. These changes were not significantly affected by the treatment with indapamide. In conclusion, eplerenone and indapamide were similarly effective in lowering office and home BPs in hypertensive patients treated with CCBs and ARBs. Eplerenone may exert more favorable effects on arterial stiffness and oxidative stress.
Keywords: Arterial stiffness; blood pressure; eplerenone; indapamide; oxidative stress.