Effects of Aliskiren-Based Therapy on Ambulatory Blood Pressure Profile, Central Hemodynamics, and Arterial Stiffness in Nondiabetic Mild to Moderate Hypertensive Patients

Renin Inhibition with Aliskiren: A Decade of Clinical Experience

The renin-angiotensin-aldosterone system (RAAS) plays a key role in the pathophysiology of arterial hypertension as well as in more complex mechanisms of cardiovascular and renal diseases. RAAS-blocking agents like angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers, have long been key components in the treatment of essential hypertension, heart failure, diabetic nephropathy, and chronic kidney disease, showing benefits well beyond blood pressure reduction. Renin blockade as the first step of the RAAS cascade finally became possible in 2007 with the approval of aliskiren, the first orally active direct renin inhibitor available for clinical use and the newest antihypertensive agent on the market. In the last decade, many clinical trials and meta-analyses have been conducted concerning the efficacy and safety of aliskiren in comparison to other antihypertensive agents, as well as the efficacy and potential clinical use of various combinations. Large trials with cardiovascular and renal endpoints attempted to show potential benefits of aliskiren beyond blood pressure lowering, as well as morbidity and mortality outcomes in specific populations such as diabetics, heart failure patients, and post-myocardial infarction individuals. The purpose of this review is to present the currently available data regarding established and future potential clinical uses of aliskiren.

Effect of single-pill irbesartan/amlodipine combination-based therapy on clinic and home blood pressure profiles in hypertension with chronic kidney diseases

We examined the efficacy of single-pill irbesartan/amlodipine combination-based therapy for 12 weeks in 20 hypertensive chronic kidney disease (CKD) patients, by evaluating self-measured home blood pressure (BP) profile. The single-pill irbesartan/amlodipine combination-based therapy decreased clinic BP and home BP (morning, evening, and nighttime BPs), and improved within-visit clinic BP variability, day-by-day home BP variability (morning and evening), and nighttime home BP variability. Furthermore, the single-pill combination-based therapy reduced albuminuria and exerted improved parameters of vascular function. These results indicate that this single-pill combination-based therapy may exert beneficial effects on clinic and home BP profiles as well as on renal and vascular damages, in hypertension with CKD.

Impact of Antihypertensive Agents on Central Systolic Blood Pressure and Augmentation Index: A Meta-Analysis

BACKGROUND

New evidence suggests that central systolic blood pressure (cSBP) and augmentation index (AI) are superior predictors of adverse cardiovascular outcomes compared to peripheral systolic BP (pSBP). We performed a meta-analysis assessing the impact of antihypertensives on cSBP and AI.

METHODS

PubMed, Cochrane Library, and CINAHL were searched until September 2014 to identify eligible articles. A DerSimonian and Laird random-effects model was used to calculate the weighted mean difference (WMD) and its 95% confidence interval (CI). Fifty-two and 58 studies incorporating 4,381 and 3,716 unique subjects were included for cSBP and AI analysis, respectively.

RESULTS

Overall, antihypertensives reduced pSBP more than cSBP (WMD 2.52 mm Hg, 95% CI 1.35 to 3.69; I (2) = 21.9%). β-Blockers (BBs) posed a significantly greater reduction in pSBP as compared to cSBP (WMD 5.19 mm Hg, 95% CI 3.21 to 7.18). α-Blockers, angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, diuretics, renin-angiotensin aldosterone system inhibitors and nicorandil reduced cSBP and pSBP in a similar manner. The overall reduction in AI from baseline was 3.09% (95% CI 2.28 to 3.90; I (2) = 84.5%). A significant reduction in AI was seen with angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, diuretics, renin-angiotensin aldosterone system inhibitors, BBs, α-blockers (ABs), nicorandil, and moxonidine reduced AI nonsignificantly.

CONCLUSIONS

BBs are not as beneficial as the other antihypertensives in reducing cSBP and AI.

Effects of pitavastatin add-on therapy on chronic kidney disease with albuminuria and dyslipidemia

Background

In non-dialysis chronic kidney disease (CKD) patients with dyslipidemia, statin therapy is recommended to prevent cardiovascular complications. Dyslipidemia has been also shown to be an independent risk factor for the progression of CKD. However, it is still unclear whether statin therapy exerts an inhibitory effect on renal deterioration in CKD patients with dyslipidemia. The purpose of the present study was to examine possible therapeutic effects of statin add-on therapy on renal function as well as parameters of lipid and glucose metabolism, arterial stiffness and oxidative stress, in comparison to diet therapy, in CKD patients with dyslipidemia.

Methods

This study was a randomized, open-label, and parallel-group trial consisted of a 12-months treatment period in non-dialysis CKD patients with alubuminuria and dyslipidemia. Twenty eight patients were randomly assigned either to receive diet counseling alone (diet therapy group) or diet counseling plus pitavastatin (diet-plus-statin therapy group), to achieve the LDL-cholesterol (LDL-C) target of <100 mg/dl.

Results

The statin treatment by pitavastatin was well tolerated in all of the patients without any significant adverse events and the average dose of pitavastatin was 1.0 ± 0.0 mg daily after treatment. After the 12-months treatment period, LDL-C was significantly lower in the diet-plus-statin therapy group compared with the diet therapy group (diet vs diet-plus-statin: LDL-C, 126 ± 5 vs 83 ± 4 mg/dL, P < 0.001). On the other hand, the diet-plus-statin therapy did not significantly reduce albuminuria or delay the decline in eGFR compared with the diet therapy, and there was no relationship between the change in LDL-C and the change in eGFR or albuminuria. However, diet therapy as well as diet-plus-statin therapy exerted similar lowering effects on the pentosidine levels (diet therapy group, baseline vs 12 months: 40 ± 4 vs 24 ± 3 ng/mL, P = 0.001; diet-plus-statin therapy, 46 ± 7 vs 34 ± 6 ng/mL, P = 0.008). Furthermore, the results of multivariate regression analysis indicated that the change in pentosidine was a significant contributor to the change in eGFR (β = −0.536, P = 0.011).

Conclusions

Although statin add-on therapy did not show additive renal protective effects, the diet therapy as well as the diet-plus-statin therapy could contribute to the reduction in plasma pentosidine in CKD patients with albuminuria and dyslipidemia.

Role of the Renin-Angiotensin-Aldosterone System and Its Pharmacological Inhibitors in Cardiovascular Diseases: Complex and Critical Issues

Hypertension is one of the major risk factor able to promote development and progression of several cardiovascular diseases, including left ventricular hypertrophy and dysfunction, myocardial infarction, stroke, and congestive heart failure. Also, it is one of the major driven of high cardiovascular risk profile in patients with metabolic complications, including obesity, metabolic syndrome and diabetes, as well as in those with renal disease. Thus, effective control of hypertension is a key factor for any preventing strategy aimed at reducing the burden of hypertension-related cardiovascular diseases in the clinical practice. Among various regulatory and contra-regulatory systems involved in the pathogenesis of cardiovascular and renal diseases, renin-angiotensin system (RAS) plays a major role. However, despite the identification of renin and the availability of various assays for measuring its plasma activity, the specific pathophysiological role of RAS has not yet fully characterized. In the last years, however, several notions on the RAS have been improved by the results of large, randomized clinical trials, performed in different clinical settings and in different populations treated with RAS inhibiting drugs, including angiotensin converting enzyme (ACE) inhibitors and antagonists of the AT1 receptor for angiotensin II (ARBs). These findings suggest that the RAS should be considered to have a central role in the pathogenesis of different cardiovascular diseases, for both therapeutic and preventive purposes, without having to measure its level of activation in each patient. The present document will discuss the most critical issues of the pathogenesis of different cardiovascular diseases with a specific focus on RAS blocking agents, including ACE inhibitors and ARBs, in the light of the most recent evidence supporting the use of these drugs in the clinical management of hypertension and hypertension-related cardiovascular diseases.

Effects of aliskiren- and ramipril-based treatment on central aortic blood pressure in elderly with systolic hypertension: a substudy of AGELESS

BACKGROUND

Systolic hypertension is the most common form of hypertension in elderly patients. There is increasing evidence that measurement of central aortic pressure (CAP) better accounts for cardiovascular risk than brachial blood pressure (BP). The Aliskiren for GEriatric LowEring of SyStolic hypertension (AGELESS) study in elderly patients with systolic hypertension showed that aliskiren-based therapy provided greater reductions in peripheral BP than ramipril-based therapy over 12 and 36 weeks of treatment. Here, we present CAP results in a substudy of elderly patients from the AGELESS study.

METHODS

This was a post hoc analysis of a 36-week, randomized, double-blind, parallel-group, active-controlled, optional-titration study in patients ≥65 years of age with systolic BP ≥140 mmHg. Changes in both central and peripheral BP and pulse pressure (PP) and changes in systolic and PP amplification ratios from baseline to the week 36 end point with aliskiren-based versus ramipril-based therapy were analyzed.

RESULTS

Of the 901 patients randomized in the overall study, 154 patients (aliskiren, n=78; ramipril, n=76) had CAP data. Numerically comparable reductions were seen for central aortic systolic pressure (CASP) in aliskiren-based therapy (baseline: 143.7±15.0; week 36: -20.3±16.2) compared with ramipril-based therapy (baseline: 147.9±11.9; week 36: -20.7±14.6). However, for the change in central aortic diastolic pressure, the least squares mean between-treatment difference (-3.6 mmHg [95% confidence interval, -6.76, -0.43; P=0.0263]) was in favor of aliskiren, while the other changes were comparable between the two groups with a trend in favor of aliskiren for CASP as well (-2.6 mmHg [95% confidence interval, -7.38, 2.19; P=0.2855)]. Correlation coefficients for change from baseline between CASP and systolic BP and between central aortic pulse pressure and PP (r=0.8, P<0.0001) were highly significant.

CONCLUSION

Aliskiren-based therapy provides comparable reductions in CASP to ramipril-based therapy. Although the results did not reach statistical significance, these findings, when coupled with those of the main study, suggest that aliskiren may offer effective control of central BP in elderly patients with systolic hypertension and may be a good alternative to ramipril.

Effects of single pill-based combination therapy of amlodipine and atorvastatin on within-visit blood pressure variability and parameters of renal and vascular function in hypertensive patients with chronic kidney disease

Both strict blood pressure (BP) control and improvements in BP profile such as BP variability are important for suppression of renal deterioration and cardiovascular complication in hypertension and chronic kidney disease (CKD). In the present study, we examined the beneficial effects of the single pill-based combination therapy of amlodipine and atorvastatin on achievement of the target BP and clinic BP profile, as well as markers of vascular and renal damages in twenty hypertensive CKD patients. The combination therapy with amlodipine and atorvastatin for 16 weeks significantly decreased clinic BP, and achievement of target BP control was attained in an average of 45% after the combination therapy in spite of the presence of no achievement at baseline. In addition, the combination therapy significantly decreased the within-visit BP variability. With respect to the effects on renal damage markers, combination therapy with amlodipine and atorvastatin for 16 weeks significantly decreased albuminuria (urine albumin-to-creatinine ratio, 1034 ± 1480 versus 733 ± 1218 mg/g-Cr, P < 0.05) without decline in estimated glomerular filtration rate. Concerning parameters of vascular function, the combination therapy significantly improved both brachial-ankle pulse wave velocity (baPWV) and central systolic BP (cSBP) (baPWV, 1903 ± 353 versus 1786 ± 382 cm/s, P < 0.05; cSBP, 148 ± 19 versus 129 ± 23 mmHg, P < 0.01). Collectively, these results suggest that the combination therapy with amlodipine and atorvastatin may exert additional beneficial effects on renal and vascular damages as well as BP profile in addition to BP lowering in hypertension with CKD.

Role of aliskiren on arterial stiffness and endothelial function in patients with primary hypertension

Arterial stiffness and endothelial dysfunction are important determinants of cardiovascular events in patients with arterial hypertension. There are few data regarding the role of aliskiren on the central hemodynamics and endothelial function in patients with uncontrolled arterial hypertension. The aim of this study was to assess the addition of aliskiren to other antihypertensive drug treatment for arterial stiffness and endothelial function. Thirty uncontrolled hypertensive patients (mean age, 60.4±12.2 years), without any other cardiovascular risk factors, were enrolled. Augmentation index (AIx) and carotid-femoral pulse wave velocity (cfPWV) by applanation tonometry and reactive hyperemia peripheral arterial tonometry (RH PAT) index using peripheral arterious tonometry at baseline and after 6 months of aliskiren titrated to 300 mg once a day was evaluated. The addition of aliskiren had no effect on values of central AIx (33.26±10.74% vs 28.86±10.74%; P=.36) but did significantly improve values of cfPWV (9.36±2.65 m/s vs 8.72±2.48 m/s; P=.04) and RH PAT index (1.64±0.57 vs 1.75±0.45; P=.05). In addition to improving systolic and diastolic blood pressure, the addition of aliskiren to concomitant antihypertensive drugs in uncontrolled hypertensive patients may be effective in improving aortic stiffness and endothelial function. These results encourage further studies to evaluate the use of aliskiren for cardiovascular prevention.

Effects of renin-angiotensin-aldosterone system inhibitors and beta-blockers on markers of arterial stiffness

Antihypertensive agents may, even within the same class, exert variable effects on arterial stiffness variables. Nebivolol could have a better impact than atenolol on arterial stiffness, by increasing the bioavailability of endothelium-derived nitric oxide. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) increase plasma renin activity (enhancing the production of angiotensin II via non-ACE-related pathways) whereas aliskiren does not, potentially affecting central hemodynamics differently. We compared the effects of two renin-angiotensin-aldosterone system (RAAS) inhibitors (quinapril and aliskiren) and 2 beta-blockers (atenolol and nebivolol) on arterial stiffness variables. Treatment-naïve patients (n = 72; 68.1% males; age, 47.6 ± 10.6 years) with uncomplicated stage I-II essential hypertension were randomly assigned to quinapril, aliskiren, atenolol, or nebivolol for 10 weeks. Central systolic and diastolic blood pressure (BP), central pulse pressure (PP), augmentation index (AIx), and pulse wave velocity (PWV) were measured at baseline, 2, and 10 weeks. The same measurements were performed in 20 normotensive subjects (65.0% males; age, 40.0 ± 8.9 years). Peripheral and central systolic and diastolic BP, peripheral PP, and PWV were significantly and similarly reduced by all agents. However, PWV continued to decline between the second and last visit in patients on quinapril and aliskiren but did not change in those on nebivolol or atenolol. Central PP and AIx decreased in patients on quinapril, aliskiren, and nebivolol but did not change in those taking atenolol. The decrease in central PP and AIx did not differ between patients on quinapril, aliskiren, and nebivolol. Despite similar reductions in peripheral BP, atenolol is less effective than nebivolol and RAAS inhibitors in improving central pulsatile hemodynamics. Aliskiren exerts similar effects on markers of arterial stiffness as quinapril. The clinical relevance of these differences remains to be established.

L/N-type calcium channel blocker cilnidipine added to renin-angiotensin inhibition improves ambulatory blood pressure profile and suppresses cardiac hypertrophy in hypertension with chronic kidney disease

Ambulatory blood pressure (BP) and heart rate (HR) profile are proposed to be related to renal deterioration and cardiovascular complication in hypertension and chronic kidney disease (CKD). In this study, we examined the beneficial effects cilnidipine, a unique L/N-type calcium channel blocker (CCB), in addition to renin-angiotensin system inhibitors, on ambulatory BP and HR profile, as well as cardiorenal function in hypertensive CKD patients. Forty-five patients were randomly assigned to the cilnidipine replacement group (n = 21) or the control CCBs group (n = 24) during a 24-week active treatment period. Although clinical BP values were similar in the cilnidipine and control CCBs groups after the treatment period, the results of ambulatory BP monitoring showed that the 24-h and daytime systolic BP levels in the cilnidipine group were significantly lower compared with the control group after the study. Furthermore, the left ventricular mass index (LVMI) was significantly decreased in the cilnidipine group compared to the control group after the study (LVMI, 135.3 ± 26.4 versus 181.2 ± 88.4, p = 0.031), with a significant difference in the changes in the LVMI between the cilnidipine and control groups (change in LVMI, −12.4 ± 23.7 versus 26.2 ± 64.4, p = 0.007). These results indicate that cilnidipine is beneficial for the suppression of pathological cardiac remodeling, at least partly, via a superior improving effect on ambulatory BP profile compared with control CCBs in hypertensive CKD patients.

Addition of aliskiren to Angiotensin receptor blocker improves ambulatory blood pressure profile and cardiorenal function better than addition of benazepril in chronic kidney disease

An altered ambulatory blood pressure (BP) and heart rate (HR) profile is related to chronic kidney disease (CKD) and cardiorenal syndrome. In this study, we examined the effects of aliskiren, when added to angiotensin II type 1 receptor blockers, on ambulatory BP and cardiorenal function in CKD. Thirty-six hypertensive CKD patients were randomly assigned to the aliskiren add-on group (n = 18) or the benazepril add-on group (n = 18). Ambulatory BP and cardiorenal function parameters were measured at baseline and 24 weeks after treatment. Compared with the benazepril group, nighttime systolic BP variability in the aliskiren group was lower after treatment. Albuminuria was decreased in the aliskiren group, but not in the benazepril group. In addition, left ventricular mass index (LVMI) was significantly lower in the aliskiren group than in the benazepril group after treatment. In the aliskiren group, multivariate linear regression analysis showed an association between changes in albuminuria and changes in nighttime systolic BP. Furthermore, there were associations between changes in LVMI and changes in daytime HR variability, as well as between changes in LVMI and changes in plasma aldosterone concentration. These results suggest that aliskiren add-on therapy may be beneficial for suppression of renal deterioration and pathological cardiac remodeling through an improvement that is effected in ambulatory BP and HR profiles.