Mineralocorticoid receptor blockade does not affect arterial compliance in middle‐aged and older adults with and without metabolic syndrome

Abstract

Aging and metabolic syndrome (MS) are associated with decreased arterial compliance but the underlying mechanisms are not completely understood. Aldosterone and activation of the mineralocorticoid receptors (MR) are thought to be elevated in MS and may contribute to reduced arterial compliance. We hypothesized that chronically elevated activation of MR is partly responsible for reduced arterial compliance in aging/MS and that MR blockade would lead to greater improvements in carotid artery compliance (CAC: high resolution ultrasonography and applanation tonometry) in middle‐aged (MA) and older (O) adults with vs. without MS. To test this hypothesis, we administered 100 mg of Eplerenone (MR blocker) or placebo per day for 4 weeks in a randomized, double blind, crossover design, in 6 MA/O adults with and 14 without MS. At baseline, brachial blood pressure (BP) was higher (mean BP: 98±2 vs. 90±3 mmHg, P=0.03) and CAC was lower (0.12±0.02 vs. 0.19±0.03 mm2/mmHg, P=0.03) in the MS group. MR blockade reduced brachial BP similarly in both groups (delta mean BP: −6±2 vs. −3±1 mmHg, P=0.1, with vs. without MS) but it did not affect CAC in either group (delta CAC: −0.01±0.01 vs. −0.02±0.03 mm2/mmHg, P=0.4, with vs. without MS). In conclusion, arterial compliance in MA/O adults with or without MS is not affected by short‐term MR blockade.Supported by AHA Grant 0865117F and NIH Grant AG032067.