Therapeutic Effects of a Selective Mineralocorticoid Receptor Blocker as an Additional Combination Antihypertensive Drug in Hypertensive Patients

抄録

Among the components of renin-angiotensin-aldosterone system, aldosterone facilitates 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) supposedly exhibit protective effects against cardiovascular organ injuries in hypertensive patients. In this study, the therapeutic effects of MRB in the combination antihypertensive treatment were examined in hypertensive patients.

Fifty mg eplerenone (EPL) was added to 24 hypertensive patients under antihypertensive drug therapy who had not achieved the target blood pressure. 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.

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 4.3 mEq/L, p = 0.014) and creatinine (0.82 to 0.87 mg/dL, P<0.001) increased slightly but significantly. Serum uric acid also increased significantly 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.

In the combination antihypertensive drug therapy, MRB is expected to reduce 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.