Central Pressure and Biomarker Responses to Renin Inhibition with Hydrochlorothiazide and Ramipril in Obese Hypertensives: The ATTAIN Study

Systemic and tissue-specific effects of aliskiren on the RAAS and carbohydrate/lipid metabolism in obese patients with hypertension

Aliskiren penetrates adipose and skeletal muscle in hypertensive patients with abdominal obesity and reduces renin-angiotensin-aldosterone system activity. After discontinuation, blood pressure-lowering effects are observed possibly through drug-tissue binding. We performed microdialysis evaluation of adipose tissue and skeletal muscle before and during an insulin-modified frequently sampled intravenous glucose tolerance test (IM-FSIGT). Aliskiren 300 mg (n = 8) or amlodipine 5 mg (n = 8) once daily were administered during a 12-week randomized treatment period. Aliskiren elicited variable changes in median interstitial angiotensin II (Ang II) in adipose (2.60-1.30 fmol/mL) and skeletal muscle (2.23-0.68 fmol/mL); amlodipine tended to increase adipose and skeletal muscle Ang II (P = .066 for skeletal muscle treatment difference). Glucose/insulin increased median plasma Ang II 1 hour after glucose injection (1.04-2.50 fmol/mL; P = .001), which was markedly attenuated by aliskiren but not amlodipine. Aliskiren increased glucose disposition index (P = .012) and tended to increase acute insulin response to glucose (P = .067). Fasting adipose glycerol (-17%; P = .064) and fasting muscle glucose dialysate (-17%; P = .025) were decreased by aliskiren but not amlodipine. In summary, aliskiren decreased Ang II production in response to glucose/insulin stimulus and elicited metabolic effects in adipose and skeletal muscle suggestive of increased whole-body glucose utilization.

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.

Effectiveness and safety of aliskiren and aliskiren hydrochlorothiazide (HCT) in a multiethnic, real-world setting

INTRODUCTION

Numerous randomized clinical trials have demonstrated the efficacy and tolerability of aliskiren and aliskiren hydrochlorothiazide (aliskiren HCT) single-pill combination therapy in patients with hypertension. The objective of the present study was to evaluate the effectiveness and safety of aliskiren-based therapy under daily life conditions in a multiethnic population.

METHODS

This observational, multicenter, noninterventional study, conducted at 420 centers in Asia and the Middle East, included adult patients with hypertension who received treatment with aliskiren or aliskiren HCT as single or add-on therapy for a planned treatment period of at least 26 weeks. The main effectiveness assessments included the proportion of patients achieving therapeutic blood pressure (BP) goal (defined as systolic BP [SBP]/diastolic BP [DBP]<140/90 mmHg, or <130/80 mmHg in patients with diabetes) and BP response, and change in mean sitting BP from baseline to study end.

RESULTS

Of 4,826 patients (mean age 51.4 years, 65.9% male, 64.5% Asian, 41.5% diabetic) included in the study, 3,473 received aliskiren and 1,353 received aliskiren HCT. Almost half the study population (48.1%) received aliskiren or aliskiren HCT as add-on therapy. The therapeutic BP goal was achieved in 49.5% of patients treated with aliskiren and 48.3% of patients receiving aliskiren HCT; attainment of BP goal increased to more than 70% when a classic BP target of <140/90 mmHg was applied for all patients. Reductions in mean sitting SBP/DBP were significantly lower versus baseline for both aliskiren (24.1/12.2 mmHg) and aliskiren HCT (27.6/14.1 mmHg) and BP response rates were consistently achieved in more than 80% of all patients during the study. Aliskiren treatment was well tolerated with only a small proportion of patients experiencing adverse events (AEs; 2.1%) and serious AEs (0.3%).

CONCLUSION

In this real-world, naturalistic setting, antihypertensive treatment with an aliskiren-based regimen was effective and well-tolerated in this multiethnic population with arterial hypertension.

Aliskiren/amlodipine as a single-pill combination in hypertensive patients: subgroup analysis of elderly patients, with metabolic risk factors or high body mass index

Aims

Blood pressure (BP) reduction in hypertensive patients is more difficult to achieve in the elderly or in the presence of comorbidities. We aimed to investigate the efficacy of the single-pill combination (SPC) aliskiren/amlodipine in hypertensive elderly patients, patients with high body mass index (BMI), with at least one metabolic risk factor, and/or type 2 diabetes mellitus (DM).

Methods

In an open-label non-randomized study, patients not adequately controlled by previous treatment with the SPC olmesarten 40/amlodipine 10 (phase 1) were switched to the SPC aliskiren 300/amlodipine 10 (phase 2). The present post-hoc analysis investigated BP reduction in phase 2 in the named subgroups. The EudraCT identifier was 2009-016693-33, ClinicalTrials.gov identifier NCT01113047.

Results

Of the 187 patients not adequately controlled in phase 1 and thus treated with the SPC aliskiren 300/amlodipine 10 in phase 2, 69 were of advanced age (≥65 years), 74 or 89 were overweight or obese (BMI 25.0–29.9 kg/m² or ≥30 kg/m², respectively), 91 had metabolic risk factors (without DM) and 41 had DM. At the beginning of phase 2, depending on the subgroup, baseline SBP was 168–169 mmHg and DBP 103–104 mmHg. After 4 weeks of treatment with aliskiren 300/amlodipine 10, SBP/DBP was lowered by −5.1/−4.8 mmHg in the total cohort, by −5.5/−5.1 mmHg in elderly patients, by −6.7/−5.5 in overweight and by −4.2/−4.5 mmHg in obese patients, by −6.4/−4.7 mmHg in patients with metabolic risk factors without DM, and by −3.3/−5.0 mmHg in DM patients. Limitations include low sample size, limited treatment duration and the fact that the post-hoc defined groups were not mutually exclusive.

Conclusions

In this study reflecting clinical practice, the aliskiren/amlodipine combination achieved effective BP reduction in elderly patients or with metabolic comorbidities, including DM that might be more difficult to treat. This consistent BP lowering pattern facilitates everyday care of patients who receive aliskiren/amlodipine.

Epidemiology and management of hypertension in the Hispanic population: a review of the available literature

Hispanics are the fastest growing ethnic minority in the USA. Among Hispanics, lack of hypertension awareness and lack of effective blood pressure (BP) control are problematic, as are higher incidence rates of hypertension-related co-morbidities compared with non-Hispanic populations. Moreover, there are currently no hypertension treatment guidelines that address the unique characteristics of this ethnic group. This article discusses ethnic differences in hypertension and cardiovascular risk factors and reviews the literature on the efficacy of antihypertensive agents in Hispanic patients, with a focus on the role of renin-angiotensin-aldosterone system (RAAS) inhibition in the management of hypertension in these patients. Hypertension in Hispanic patients can be challenging to manage, in part because this population has a higher prevalence of obesity, diabetes, and metabolic syndrome compared with non-Hispanic whites. The presence of these co-morbidities suggests that RAAS-inhibitor-based therapies may be particularly beneficial in this population. However, few studies have evaluated the efficacy of antihypertensive treatments in Hispanic patients. Two outcomes studies in hypertensive patients have shown the benefits of treating Hispanic patients with antihypertensive therapy and included RAAS inhibitors as part of the treatment regimen. In addition, BP-lowering trials have shown the antihypertensive efficacy of angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, and direct renin inhibitors, although data on the latter are more limited. Additional studies are needed to more thoroughly evaluate the effects of RAAS inhibitors (and other drug classes) on outcomes and BP lowering in the Hispanic hypertensive population.