THERAPEUTIC EFFECTS OF MINERAL CORTICOID RECEPTOR BLOCKER IN THE COMBINATION ANTIHYPERTENSIVE DRUG THERAPY IN HYPERTENSIVE PATIENTS

Abstract

Objective: Among the components of renin-angiotensin-aldosterone system, aldosterone is supposed to facilitate the progression of cardiovascular organ injuries not only by promoting renal tubular Na reabsorption but also by causing oxidative stress, inflammation and cardiovascular tissue hypertrophy and fibrosis. Therefore, mineral corticoid receptor blockers (MRB) are expected to exhibit protective effects against cardiovascular organ injuries in hypertensive patients. In the present study, the therapeutic effects of MRB in the combination antihypertensive treatment were examined in hypertensive patients. Design and method: Fifty mg eplerenone (EPL) was added to 24 hypertensive patients under antihypertensive drug therapy who were not achieved the target blood pressure levels. The combination was continued for 3 to 4 months and the effects on blood pressure (BP) and laboratory data including renal function and cardiovascular endocrine system were evaluated. Results: After 3–4 months, office BP was lowered from 148/91 to 135/86 mmHg (p < 0.001/p = 0.002) as well as the home BP (morning 150/86 to 134/81, p = 0.001/p = 0.033; evening 139/80 to 127/74, p = 0.005/p = 0.030). Serum K (4.2 to 4.3mEq/L, p = 0.014) and creatinine (0.82 to 0.87 mg/dL, P < 0.001) were slightly but significantly increased. Serum uric acid was significantly also increased from 5.8 to 6.4 mg/dL (p = 0.015). However, the indices of glucose metabolism and serum lipids were not affected. In addition to the natural increases in plasma renin and aldosterone, plasma B-type natriuretic peptide (BNP: 23 to 17 pg/mL, p = 0.028) and urinary albumin excretion (111 to 70 mg/gCr, p = 0.009) were significantly decreased. Conclusions: In the combination antihypertensive drug therapy, MRB is expected to cardiac and renal injuries and the influences on glucose and lipid metabolisms seem negligible, however, care should be taken for the development of hyperuricemia and renal dysfunction in addition to hyperkalemia.