Benefits of the angiotensin II receptor antagonist olmesartan in controlling hypertension and cerebral hemodynamics after stroke

Abstract

The purpose of this study was to assess the relative benefits of angiotensin II receptor blockers (ARBs) and calcium channel blockers (CCBs) on cerebral hemodynamics and rehabilitation outcome in hypertensive stroke patients. We randomly assigned 35 patients to either the olmesartan (n¼18) or amlodipine (n¼17) treatment groups for 8 weeks. Changes in cerebral blood flow (CBF) and cerebrovascular reserve capacity (CRC) were quantified using xenon-CT and rehabilitation parameters were also measured. Over 24 h, olmesartan and amlodipine both reduced blood pressure (BP) to similar levels (systolic BP, À16.1±2.7 mm Hg vs. À15.7±3.1; diastolic BP, À9.2±2.9 vs. À8.6±3.3 mm Hg, respectively). In olmesartan-treated patients, CBF significantly increased in the affected and unaffected hemispheres, and CRC increased significantly in the affected hemisphere. No increases in CBF and CRC were observed in amlodipine-treated patients. Patients treated with olmesartan showed effective rates of improvement in hand (30.0%), upper extremities (40.0%) and lower extremities (100.0%), measured by Brunnstrom stage; these improvements were significantly different from those in amlodipine-treated patients for the total (Po0.02) and lower extremity (Po0.05) scores. There were no significant differences in Barthel indices and MiniMental State Examination (MMSE) scores. Olmesartan, but not amlodipine, had beneficial effects on CBF, CRC and rehabilitation outcomes in hypertensive stroke patients, by a mechanism independent of BP reduction and possibly by normalizing CBF autoregulation. Our results suggest that olmesartan may improve cerebral circulation and rehabilitation in hypertensive stroke patients in whom CBF autoregulation is impaired.

A randomized, double-blind, four-arm parallel-group study of the efficacy and safety of azelnidipine and olmesartan medoxomil combination therapy compared with each monotherapy in Japanese patients with essential hypertension: the REZALT study

“…A sample size of 180 patients per group would have 90% power to detect all the differences of 6 and 3 mm Hg in the primary SBP and DBP end points between the O/A (20/16) group and the monotherapy (AZL (16) or OLM (20)) group assuming that the common s.d. would be 11 and 8 mm Hg, respectively, and the correlation coefficient between SBP and DBP would be 0.7 using 2000 simulations of a t-test with a 0.05 two-sided significance level.…”

“…15,16 In addition to reducing BP, OLM is reported to have the following effects: inhibition of vascular remodeling, anti-inflammatory effect, antiatherosclerotic effect, maintaining cerebral blood flow and prevention of microalbuminuria. [17][18][19][20] AZL is also reported to have the following effects: antioxidative effect, antiatherosclerotic effect, maintaining cerebral blood flow, prevention of proteinuria and PR reduction which is not observed with amlodipine. [21][22][23][24][25] Furthermore, combined use of ARB and AZL is reported to prevent microalbuminuria in diabetic nephropathy patients.…”

Liver growth factor treatment reverses vascular and plasmatic oxidative stress in spontaneously hypertensive rats

“…Therefore, there is great interest in the development of strategies able to reduce oxidative stress in hypertension-related pathologies [10]. One of the most widely used approaches is targeting the renin-angiotensin system with angiotensin receptor ATR1 antagonists [11][12][13], angiotensin-converting enzyme inhibitors [14] or combined therapies [15]. A second strategy is the use of small molecules to inhibit enzymatic ROS and RNS-producing systems such as NADPH oxidase [16] and xanthine oxidase [17], and a third approach is to employ ROS scavengers [18][19][20].…”

Effects of telmisartan on the cerebral circulation of hypertensive patients with chronic-stage stroke

“…Several studies have described the effects of the ARBs losartan, valsartan and olmesartan in maintaining and increasing cerebral blood flow (CBF) and improving cerebral perfusion reserve capacity in chronic-stage stroke patients. [6][7][8][9] Although previous studies on telmisartan have reported reduced infarct size [10][11][12] and increased CBF 13 in mouse and rat cerebral ischemia models, there have not been any clinical studies on the effects of telmisartan on cerebral circulation in chronic-stage stroke patients.…”