Angiotensin-Converting Enzyme Inhibitors and Calcium Channel Blockers for Coronary Heart Disease and Stroke Prevention

Calcium channel blocker compared with angiotensin receptor blocker for patients with hypertension: a meta-analysis of randomized controlled trials

To explore the clinical effects of a calcium channel blocker compared with an angiotensin II receptor blocker in hypertensive patients, the authors collected data from randomized controlled trials. The pooled outcomes were all-cause mortality, stroke, myocardial infarction, and heart failure. Eight head-to-head trials enrolling 25,084 patients were included. There was no significant mortality difference in the two arms (relative risk, 0.99; 95% confidence interval, 0.91-1.07). However, calcium channel blockers were more effective in reducing stroke (relative risk, 0.87; 95% confidence interval, 0.76-0.99) and myocardial infarction incidence (relative risk, 0.86; 95% confidence interval, 0.76-0.98). There was no significant difference with heart failure incidence between the two arms but a lower trend in patients with angiotensin II receptor blockers was noted (relative risk, 1.4; 95% confidence interval, 0.99-1.98). The meta-analysis suggested that initially use of a calcium channel blocker might be superior to an angiotensin II receptor blocker for prevention of stroke and myocardial infarction.

Amlodipine and cardiovascular outcomes in hypertensive patients: meta-analysis comparing amlodipine-based versus other antihypertensive therapy

BACKGROUND/AIMS

This meta-analysis compared the effects of amlodipine besylate, a charged dihydropyridine-type calcium channel blocker (CCB), with other non-CCB antihypertensive therapies regarding the cardiovascular outcome.

METHODS

Data from seven long-term outcome trials comparing the cardiovascular outcomes of an amlodipine-based regimen with other active regimens were pooled and analyzed.

RESULTS

The risk of myocardial infarction was significantly decreased with an amlodipine-based regimen compared with a non-CCB-based regimen (odds ratio [OR], 0.91; 95% confidence interval [CI], 0.84 to 0.99; p = 0.03). The risk of stroke was also significantly decreased (OR, 0.84; 95% CI, 0.79 to 0.90; p < 0.00001). The risk of heart failure increased slightly with marginal significance for an amlodipine-based regimen compared with a non-CCB-based regimen (OR, 1.14; 95% CI, 0.98 to 1.31; p = 0.08). However, when compared overall with β-blockers and diuretics, amlodipine showed a comparable risk. Amlodipine-based regimens demonstrated a 10% risk reduction in overall cardiovascular events (OR, 0.90; 95% CI, 0.82 to 0.99; p = 0.02) and total mortality (OR, 0.95; 95% CI, 0.91 to 0.99; p = 0.01).

CONCLUSIONS

Amlodipine reduced the risk of total cardiovascular events as well as all-cause mortality compared with non-CCB-based regimens, indicating its benefit for high-risk cardiac patients.

Can we identify response markers to antihypertensive drugs? First results from the IDEAL Trial

Current antihypertensive strategies do not take into account that individual characteristics may influence the magnitude of blood pressure (BP) reduction. Guidelines promote trial-and-error approaches with many different drugs. We conducted the Identification of the Determinants of the Efficacy of Arterial blood pressure Lowering drugs (IDEAL) Trial to identify factors associated with BP responses to perindopril and indapamide. IDEAL was a cross-over, double-blind, placebo-controlled trial, involving four 4-week periods: indapamide, perindopril and two placebo. Eligible patients were untreated, hypertensive and aged 25-70 years. The main outcome was systolic BP (SBP) response to drugs. The 112 participants with good compliance had a mean age of 52. One in every three participants was a woman. In middle-aged women, the SBP reduction from drugs was -11.5 mm Hg (indapamide) and -8.3 mm Hg (perindopril). In men, the response was significantly smaller: -4.8 mm Hg (indapamide) and -4.3 (perindopril) (P for sex differences 0.001 and 0.015, respectively). SBP response to perindopril decreased by 2 mm Hg every 10 years of age in both sexes (P=0.01). The response to indapamide increased by 3 mm Hg every 10 years of age gradient in women (P=0.02). Age and sex were important determinants of BP response for antihypertensive drugs in the IDEAL population. This should be taken into account when choosing drugs a priori.

The prognostic values of leukocyte Rho kinase activity in acute ischemic stroke

Objective. It has been reported that leukocyte ROCK activity is elevated in patients after ischemic stroke, but it is unclear whether leukocyte ROCK activity is associated with clinical outcomes following acute stroke events. The objective of this study is to investigate if leukocyte ROCK activity can predict the outcomes in patients with acute ischemic stroke. Materials and Methods. We enrolled 110 patients of acute ischemic stroke and measured the leukocyte ROCK activity and plasma level of inflammatory cytokines to correlate the clinical outcomes of these patients. Results. The leukocyte ROCK activity at 48 hours after admission in acute ischemic stroke patients was higher as compared to a risk-matched population. The leukocyte ROCK activity significantly correlated with National Institute of Health Stroke Scale (NIHSS) difference between admission and 90 days after stroke event. Kaplan-Meier survival estimates showed lower stroke-free survival during follow-up period in patients with high leukocyte ROCK activity or plasma hsCRP level. Leukocyte ROCK activity independently predicted the recurrent stroke in patients with atherosclerotic stroke. Conclusions. This study shows elevated leukocyte ROCK activity in patients with ischemic stroke as compared to risk-matched subjects and is an independent predictor for recurrent stroke.

Blood pressure control among stroke patients in Thailand--the i-STROKE study

BACKGROUND

Direct correlation between stroke mortality and hypertension calls for a tight blood pressure (BP) control. Our study determined the prevalence of the BP control and evaluated current clinical practices on hypertension management in stroke patients in Thailand.

METHODS

This multicenter, cross-sectional, retrospective, observational study was carried out between February 2010 and January 2011 and enrolled stroke patients aged 45 years or older with ictus incidence 12,030 days before the enrollment. The events were confirmed by either computerized tomography scan or magnetic resonance imaging. Patient data including demographics, medical, and clinical history were collected.

RESULTS

At enrollment, 274 of 558 (49.1%) patients had controlled arterial BP with an average pressure of 134.220.4/78.812.8 mm Hg; 412 (73.8%) patients received antihypertensive medications and the most common use was angiotensin-converting enzyme inhibitors (ACEIs), reported in 200 (35.8%) patients. With questionnaire, insufficient antihypertensive use and lack of patients' awareness were the 2 most common reasons given by physicians for the patients' uncontrolled BP. Factors identified to have adverse association with the controlled BP at enrollment were diabetes at baseline, stage II hypertension, stage I hypertension, and the use of ACEIs at discharge (odds ratio of .18, .24, .30 [P < .001], and .53 [P = .009], respectively).

CONCLUSIONS

Despite clinical evidence of the benefits of the BP control in reduction of secondary stroke events, a substantial number of stroke patients in Thailand do not achieve their BP targets, and this could possibly be a result of inadequate use of antihypertensive therapies and lack of compliance to BP management guidelines.

Simultaneous determination of losartan, losartan acid and amlodipine in human plasma by LC-MS/MS and its application to a human pharmacokinetic study

INTRODUCTION

A simple, rapid and sensitive liquid chromatography-tandem mass spectrometric assay method has been developed and fully validated for simultaneous quantification of losartan and its active metabolite, losartan carboxylic acid, and amlodipine in human plasma. Irbesartan was used as an internal standard.

MATERIALS AND METHODS

The analytes were extracted from human plasma samples by solid-phase extraction technique using Oasis HLB cartridges, (Waters Corporation, Mumbai, India). The reconstituted samples were chromatographed on a C18 column by using an 85:15, v/v mixture of methanol and 0.1% v/v formic acid as the mobile phase at a flow rate of 1.0 mL/min. A detailed validation of the method was performed as per the FDA guidelines.

RESULTS

The calibration curves obtained were linear (r ≥ 0.99) over the concentration range of 0.5-1000 ng/mL for losartan and for its active metabolite losartan acid and 0.05-10.1 ng/mL for amlodipine. The results of the intra- and inter-day precision and accuracy studies were well within the acceptable limits.

CONCLUSIONS

A run time of 2.5 min for each sample made it possible to analyze more than 300 plasma samples per day. The proposed method was found to be applicable to clinical studies.

Global QSAR modeling of logP values of phenethylamines acting as adrenergic alpha-1 receptor agonists

Global QSAR models predict biological response of molecular structures which are generic in particular class. A global QSAR dataset admits structural features derived from larger chemical space, intricate to model but more applicable in medicinal chemistry. The present work is global in either sense of structural diversity in QSAR dataset or large number of descriptor input. Forty phenethylamine structure derivatives were selected from a large pool (904) of similar phenethylamines available in Pubchem database. LogP values of selected candidates were collected from physical properties database (PHYSPROP) determined in identical set of conditions. Attempts to model logP value have produced significant QSAR models. MLR aided linear one-variable and two-variable QSAR models with their respective R(2) (0.866, 0.937), R(2)A (0.862, 0.932), F-stat (181.936, 199.812) and Standard Error (0.365, 0.255) are statistically fit and found predictive after internal validation and external validation. The descriptors chosen after improvisation and optimization reveal mechanistic part of work in terms of Verhaar model of Fish base-line toxicity from MLOGP, i.e. (BLTF96) and 3D-MoRSE -signal 15 /unweighted molecular descriptor calculated by summing atom weights viewed by a different angular scattering function (Mor15u) are crucial in regulation of logP values of phenethylamines.

Beneficial effect of calcium channel blockers on home blood pressure variability in the morning in patients with type 2 diabetes

Aims/Introduction

Recent studies have shown the association between blood pressure variability and cardiovascular events. The present study was designed to investigate the relationship between antihypertensive drug class and home blood pressure variability in patients with type 2 diabetes.

Materials and Methods

We compared home blood pressure variability among patients treated with calcium channel blockers (n = 44), with angiotensin II receptor blockers and/or angiotensin‐converting enzyme inhibitors (n = 159), and with calcium channel blockers combined with angiotensin II receptor blockers and/or angiotensin‐converting enzyme inhibitors (n = 183). Next, we analyzed the effect of calcium channel blockers on morning blood pressure variability using multiple linear regression analysis.

Results

Coefficient variation of morning systolic blood pressure in patients treated with calcium channel blockers was significantly lower than that in patients treated with angiotensin II receptor blockers and/or angiotensin‐converting enzyme inhibitors (P = 0.036). Multivariate linear regression analyses showed that treatment with calcium channel blockers was significantly correlated with coefficient variation of morning systolic blood pressure (β = −0.264, P = 0.001).

Conclusions

The present study implies a possibility for validity on selecting calcium channel blockers in hypertensive patients with type 2 diabetes to reduce home blood pressure variability.

Beta-blockers for hypertension

BACKGROUND

This review is an update of the Cochrane Review published in 2007, which assessed the role of beta-blockade as first-line therapy for hypertension.

OBJECTIVES

To quantify the effectiveness and safety of beta-blockers on morbidity and mortality endpoints in adults with hypertension.

SEARCH METHODS

In December 2011 we searched the Cochrane Central Register of Controlled Trials, Medline, Embase, and reference lists of previous reviews; for eligible studies published since the previous search we conducted in May 2006.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of at least one year duration, which assessed the effects of beta-blockers compared to placebo or other drugs, as first-line therapy for hypertension, on mortality and morbidity in adults.

DATA COLLECTION AND ANALYSIS

We selected studies and extracted data in duplicate. We expressed study results as risk ratios (RR) with 95% confidence intervals (CI) and combined them using the fixed-effects or random-effects method, as appropriate.

MAIN RESULTS

We included 13 RCTs which compared beta-blockers to placebo (4 trials, N=23,613), diuretics (5 trials, N=18,241), calcium-channel blockers (CCBs: 4 trials, N=44,825), and renin-angiotensin system (RAS) inhibitors (3 trials, N=10,828). Three-quarters of the 40,245 participants on beta-blockers used atenolol. Most studies had a high risk of bias; resulting from various limitations in study design, conduct, and data analysis.Total mortality was not significantly different between beta-blockers and placebo (RR 0.99, 95%CI 0.88 to 1.11; I(2)=0%), diuretics or RAS inhibitors, but was higher for beta-blockers compared to CCBs (RR 1.07, 95%CI 1.00 to 1.14; I(2)=2%). Total cardiovascular disease (CVD) was lower for beta-blockers compared to placebo (RR 0.88, 95%CI 0.79 to 0.97; I(2)=21%). This is primarily a reflection of the significant decrease in stroke (RR 0.80, 95%CI 0.66 to 0.96; I(2)=0%), since there was no significant difference in coronary heart disease (CHD) between beta-blockers and placebo. There was no significant difference in withdrawals from assigned treatment due to adverse events between beta-blockers and placebo (RR 1.12, 95%CI 0.82 to 1.54; I(2)=66%).The effect of beta-blockers on CVD was significantly worse than that of CCBs (RR 1.18, 95%CI 1.08-1.29; I(2)=0%), but was not different from that of diuretics or RAS inhibitors. In addition, there was an increase in stroke in beta-blockers compared to CCBs (RR 1.24, 95%CI 1.11-1.40; I(2)=0%) and RAS inhibitors (RR 1.30, 95%CI 1.11 to 1.53; I(2)=29%). However, CHD was not significantly different between beta-blockers and diuretics, CCBs or RAS inhibitors. Participants on beta-blockers were more likely to discontinue treatment due to adverse events than those on RAS inhibitors (RR 1.41, 95% CI 1.29 to 1.54; I(2)=12%), but there was no significant difference with diuretics or CCBs.

AUTHORS' CONCLUSIONS

Initiating treatment of hypertension with beta-blockers leads to modest reductions in cardiovascular disease and no significant effects on mortality. These effects of beta-blockers are inferior to those of other antihypertensive drugs. The GRADE quality of this evidence is low, implying that the true effect of beta-blockers may be substantially different from the estimate of effects found in this review. Further research should be of high quality and should explore whether there are differences between different sub-types of beta-blockers or whether beta-blockers have differential effects on younger and elderly patients.

An angiotensin II receptor blocker-calcium channel blocker combination prevents cardiovascular events in elderly high-risk hypertensive patients with chronic kidney disease better than high-dose angiotensin II receptor blockade alone

The OSCAR study was a multicenter, prospective randomized open-label blinded end-point study of 1164 Japanese elderly hypertensive patients comparing the efficacy of angiotensin II receptor blocker (ARB) uptitration to an ARB plus calcium channel blocker (CCB) combination. In this prospective study, we performed prespecified subgroup analysis according to baseline estimated glomerular filtration rate (eGFR) with chronic kidney disease (CKD) defined as an eGFR <60 ml/min per 1.73 m². Blood pressure was lower in the combined therapy than in the high-dose ARB cohort in both groups with and without CKD. In patients with CKD, significantly more primary events (a composite of cardiovascular events and noncardiovascular death) occurred in the high-dose ARB group than in the combination group (30 vs. 16, respectively, hazard ratio 2.25). Significantly more cerebrovascular and more heart failure events occurred in the high-dose ARB group than in the combination group. In patients without CKD, however, the incidence of primary events was similar between the two treatments. The treatment-by-subgroup interaction was significant. Allocation to the high-dose ARB was a significant independent prognostic factor for primary events in patients with CKD. Thus, the ARB plus CCB combination conferred greater benefit in prevention of cardiovascular events in patients with CKD compared with high-dose ARB alone. Our findings provide new insight into the antihypertensive strategy for elderly hypertensive patients with CKD.

Is it the blood pressure or the blood vessel?

The physiologic link between vascular health and arterial pressure makes it difficult to separate the adverse effects of pressure and vascular functional and structural alterations in determining the adverse complications of hypertension. Since endothelial dysfunction and nitric oxide deficiency are characteristic features of hypertension and of other risk factors for morbid events, it is proposed that blood pressure elevation may be viewed in part as a complication of functional and structural changes in the microcirculation, and that structural changes in the conduit arteries leading to morbid events may be viewed as a complication of both pressure elevation and endothelial dysfunction. Improvement in endothelial dysfunction will relax the microcirculation and lower blood pressure. Thus pressure elevation and its lowering in resposne to treatment serves as a useful guide to the vascular abnormality and its amelioration, but vascular structural abnormalities are the proximate cause of vascular events and therapy aimed at the vasculature rather than the pressure may serve as a more sensitive and specific guide to treatment.

Beyond blood pressure: Arterial stiffness as a new biomarker of cardiovascular disease

Arterial stiffness of the large, elastic conduit arteries is considered a risk marker of vascular aging, as well as a new biomarker of cardiovascular (CV) disease. Arterial stiffness also plays an important role in the development of isolated systolic hypertension (ISH) in the middle-aged and elderly population. ISH is characterized by an increase in pulse pressure (PP) in association with a rise in systolic blood pressure (SBP) and a fall in diastolic blood pressure (DBP). Increased PP, however, is not always a good surrogate for arterial stiffening because of the frequent discrepancy between peripheral brachial and central aortic PP values due to varying pressure amplification. Therefore, noninvasive, easily performed methods for more direct measurement of arterial stiffness and wave reflection, such as aortic pulse wave velocity (PWV) and pulse wave analysis, have been developed for clinical use. The present review aims to provide an understanding of the pathophysiology of arterial stiffness and wave reflection, to review the various techniques for their measurement, and to explore their usefulness in predicting CV risk and therapeutic benefit in comparison with traditional brachial artery cuff blood pressure (BP) by sphygmomanometry.

Hypertension in the metabolic syndrome

Increased blood pressure is considered an important component of metabolic syndrome. More than 85% of those with metabolic syndrome, even in the absence of diabetes, have elevated blood pressure (BP) or hypertension. The association of elevated BP with the metabolic syndrome is strongly linked through the causative pathway of obesity. Hypertension is the leading metabolic syndrome risk factor that predisposes to increased cardiovascular morbidity and mortality, and is additionally an important risk factor for development of chronic kidney disease in the presence of obesity, the metabolic syndrome, and microalbuminuria. Control of blood pressure in persons with the metabolic syndrome may prevent a significant number of coronary heart disease events. The primary modality of treatment is lifestyle intervention with reduced caloric intake and increased physical activity. Pharmacologic intervention is indicated on the basis of the severity of BP elevation, associated cardiovascular risk factors, and the presence of target organ damage.

Cardiovascular outcomes in high-risk patients without heart failure treated with ARBs: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Angiotensin II type 1 receptor antagonists (ARBs) are widely used as a substitute for angiotensin-converting enzyme inhibitors (ACEIs) to treat patients without heart failure, but their effect on cardiovascular morbidity and mortality has not been clearly determined. A systematic review and meta-analysis was undertaken to determine the impact of ARBs on cardiovascular outcomes in high-risk patients without heart failure.

METHODS

A computerized literature search was carried out using PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, and EMBASE, from January 1990 to April 2008. The following search terms were used: 'hypertension', 'clinical trial', 'sartan', 'ARB', 'angiotensin receptor antagonist', 'losartan', 'candesartan', 'valsartan', 'irbesartan', 'eprosartan', 'telmisartan', 'olmesartan', 'coronary disease', 'coronary heart disease', 'myocardial infarction', 'cardiovascular disease', 'cerebrovascular disease', and 'stroke'. Criteria for inclusion of clinical trials in our meta-analysis were the use of a randomized control group not receiving an ARB and the availability of outcome data for any one of four endpoints: myocardial infarction (MI), stroke, cardiovascular death, and all-cause death (these were not always pre-specified endpoints in all trials). Out of 45 potentially relevant studies, 37 trials met the inclusion criteria. We tabulated all occurrences of these four adverse outcomes.

RESULTS

Homogenous subgroups were combined by means of a fixed-effects model, while heterogenous subgroups were not combined. In the subgroup without heart failure, ARBs, when compared with the control group, had an odds ratio of 1.09 (95% CI 1.00, 1.18; p = 0.05) for MI. Other endpoints, namely, cardiovascular death and all-cause death, did not reach statistical significance. There was a clear trend for fewer strokes in the ARB group, but these studies were clearly heterogenous, and therefore a pooled risk estimate was not computed.

CONCLUSION

After pooling more than 89 000 patients, there is no evidence to suggest that ARBs confer cardiovascular protection akin to ACEIs, and the results that emerged are not in favor of ARB therapy in terms of its use as a substitute for ACEIs in non-heart failure patients. ARBs may have a small benefit in terms of stroke risk, but the studies are heterogenous, making it very difficult to quantify this effect. Given that ACEIs protect against both stroke and MI, caution is advised in the use of ARBs as a substitute for ACEIs in patients without a heart failure indication, who are tolerant of an ACEI.

Metabolic effects of manidipine

The calcium channel antagonists (CCAs) were originally introduced as vasodilators for the treatment of coronary heart disease, but are now also noted for their clinical efficacy in the management of hypertension. Data from large clinical studies have shown that CCAs are not associated with the undesirable metabolic effects (e.g. worsening of dyslipidemia and reduction of insulin sensitivity) seen with older agents such as thiazide diuretics and beta-adrenoceptor antagonists (beta-blockers) that are used to treat hypertension. Indeed, reductions in cardiovascular risk and rates of onset of new cases of diabetes mellitus have been reported in trials in patients with hypertension treated with CCAs. These beneficial effects extend beyond those expected to accompany reductions in BP. Until recently, the biochemical effects underlying these metabolic changes were only poorly understood, but pharmacologic studies have now started to shed more light on these issues. Of particular interest are studies with manidipine, some of which suggest that this agent may be associated with greater improvements in insulin sensitivity and may have better renal protective properties than other CCAs. Confirmation of potential differences among CCAs in terms of the relative magnitude of any beneficial metabolic effects requires further study. Ongoing research is expected to clarify further the action of these agents at the cellular level and to assist with the optimization of antihypertensive therapy, particularly in patients with elevated cardiovascular risk profiles.

Beta-blockers for hypertension

BACKGROUND

This review is an update of the Cochrane Review published in 2007, which assessed the role of beta-blockade as first-line therapy for hypertension.

OBJECTIVES

To quantify the effectiveness and safety of beta-blockers on morbidity and mortality endpoints in adults with hypertension.

SEARCH METHODS

In December 2011 we searched the Cochrane Central Register of Controlled Trials, Medline, Embase, and reference lists of previous reviews; for eligible studies published since the previous search we conducted in May 2006.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of at least one year duration, which assessed the effects of beta-blockers compared to placebo or other drugs, as first-line therapy for hypertension, on mortality and morbidity in adults.

DATA COLLECTION AND ANALYSIS

We selected studies and extracted data in duplicate. We expressed study results as risk ratios (RR) with 95% confidence intervals (CI) and combined them using the fixed-effects or random-effects method, as appropriate.

MAIN RESULTS

We included 13 RCTs which compared beta-blockers to placebo (4 trials, N=23,613), diuretics (5 trials, N=18,241), calcium-channel blockers (CCBs: 4 trials, N=44,825), and renin-angiotensin system (RAS) inhibitors (3 trials, N=10,828). Three-quarters of the 40,245 participants on beta-blockers used atenolol. Most studies had a high risk of bias; resulting from various limitations in study design, conduct, and data analysis.Total mortality was not significantly different between beta-blockers and placebo (RR 0.99, 95%CI 0.88 to 1.11; I(2)=0%), diuretics or RAS inhibitors, but was higher for beta-blockers compared to CCBs (RR 1.07, 95%CI 1.00 to 1.14; I(2)=2%). Total cardiovascular disease (CVD) was lower for beta-blockers compared to placebo (RR 0.88, 95%CI 0.79 to 0.97; I(2)=21%). This is primarily a reflection of the significant decrease in stroke (RR 0.80, 95%CI 0.66 to 0.96; I(2)=0%), since there was no significant difference in coronary heart disease (CHD) between beta-blockers and placebo. There was no significant difference in withdrawals from assigned treatment due to adverse events between beta-blockers and placebo (RR 1.12, 95%CI 0.82 to 1.54; I(2)=66%).The effect of beta-blockers on CVD was significantly worse than that of CCBs (RR 1.18, 95%CI 1.08-1.29; I(2)=0%), but was not different from that of diuretics or RAS inhibitors. In addition, there was an increase in stroke in beta-blockers compared to CCBs (RR 1.24, 95%CI 1.11-1.40; I(2)=0%) and RAS inhibitors (RR 1.30, 95%CI 1.11 to 1.53; I(2)=29%). However, CHD was not significantly different between beta-blockers and diuretics, CCBs or RAS inhibitors. Participants on beta-blockers were more likely to discontinue treatment due to adverse events than those on RAS inhibitors (RR 1.41, 95% CI 1.29 to 1.54; I(2)=12%), but there was no significant difference with diuretics or CCBs.

AUTHORS' CONCLUSIONS

Initiating treatment of hypertension with beta-blockers leads to modest reductions in cardiovascular disease and no significant effects on mortality. These effects of beta-blockers are inferior to those of other antihypertensive drugs. The GRADE quality of this evidence is low, implying that the true effect of beta-blockers may be substantially different from the estimate of effects found in this review. Further research should be of high quality and should explore whether there are differences between different sub-types of beta-blockers or whether beta-blockers have differential effects on younger and elderly patients.

Progress report on the first sub-Saharan Africa trial of newer versus older antihypertensive drugs in native black patients

BACKGROUND

The epidemic surge in hypertension in sub-Saharan Africa is not matched by clinical trials of antihypertensive agents in Black patients recruited in this area of the world. We mounted the Newer versus Older Antihypertensive agents in African Hypertensive patients (NOAAH) trial to compare, in native African patients, a single-pill combination of newer drugs, not involving a diuretic, with a combination of older drugs including a diuretic.

METHODS

Patients aged 30 to 69 years with uncomplicated hypertension (140 to 179/90 to 109 mmHg) and ≤2 associated risk factors are eligible. After a four week run-in period off treatment, 180 patients have to be randomized to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg (R) or amlodipine/valsartan 5/160 mg (E). To attain blood pressure <140/<90 mmHg during six months, the doses of bisoprolol and amlodipine should be increased to 10 mg/day with the possible addition of up to 2 g/day α-methyldopa.

RESULTS

At the time of writing of this progress report, of 206 patients enrolled in the run-in period, 140 had been randomized. At randomization, the R and E groups were similar (P ≥ 0.11) with respect to mean age (50.7 years), body mass index (28.2 kg/m(2)), blood pressure (153.9/91.5 mmHg) and the proportions of women (53.6%) and treatment naïve patients (72.7%). After randomization, in the R and E groups combined, blood pressure dropped by 18.2/10.1 mmHg, 19.4/11.2 mmHg, 22.4/12.2 mmHg and 25.8/15.2 mmHg at weeks two (n = 122), four (n = 109), eight (n = 57), and 12 (n = 49), respectively. The control rate was >65% already at two weeks. At 12 weeks, 12 patients (24.5%) had progressed to the higher dose of R or E and/or had α-methyldopa added. Cohort analyses of 49 patients up to 12 weeks were confirmatory. Only two patients dropped out of the study.

CONCLUSIONS

NOAAH (NCT01030458) demonstrated that blood pressure control can be achieved fast in Black patients born and living in Africa with a simple regimen consisting of a single-pill combination of two antihypertensive agents. NOAAH proves that randomized clinical trials of cardiovascular drugs in the indigenous populations of sub-Saharan Africa are feasible.

A Polypill for All? Critical Review of the Polypill Literature for Primary Prevention of Cardiovascular Disease and Stroke

Objective:

To evaluate the efficacy and safety of the polypill for prevention of cardiovascular disease (CVD) and stroke and to present literature related to the polypill components (statin, aspirin, antihypertensive) for primary prevention of CVD and stroke.

Data Sources:

A literature search was conducted in MEDLINE (1948-January 2011) and EMBASE (1974-January 2011) using the terms polypill and Polycap. When limited to clinical trials, systematic reviews, or meta-analyses, 7 studies were identified. Bibliographies of pertinent review articles and studies were scanned for additional references. A similar search was conducted to identify literature related to the use of polypill components for primary prevention of CVD and stroke.

Study Selection and Data Extraction:

Studies that evaluated the hypothetical benefits of a polypill and controlled trials that assessed a formulation of the polypill related to prevention of CVD and stroke were included. Studies were assessed for efficacy, safety, drug interactions, and clinical pharmacokinetics.

Data Synthesis:

An initial study to predict benefit estimated that a hypothetical polypill would reduce diastolic blood pressure by 11 mm Hg and low-density lipoprotein cholesterol (LDL-C) by 70 mg/dL, thus reducing the relative risks of CVD and stroke by 68% and 80%, respectively. One clinical trial in patients at low risk for CVD and stroke found that diastolic Wood pressure was reduced by 1.6 mm Hg and LDL-C was reduced by 17.7 mg/dL, correlating with 44% and 21% reduction in the relative risks of CVD and stroke, respectively. Studies in higher risk patients reported reductions in systolic blood pressure of up to 28.8 mm Hg and in LDL-C of up to 54 mg/dL, correlating with 62% and 60% relative reduction in risks of CVD and stroke, respectively.

Conclusions:

Polypill study results have been more modest than originally theorized. However, results show promise in patients at higher risk for CVD and stroke.

The evolution and refinement of traditional risk factors for cardiovascular disease

Traditional risk factors for cardiovascular disease such as systemic hypertension and hypercholesterolemia, all described more than half a century ago, are relatively few in number. Efforts to expand the epidemiologic canon have met with limited success because of the high hurdle of causality. Fortunately, another solution to current deficiencies in risk assessment-in particular, the underestimation of risk both before and after initiation of pharmacotherapy-may exist. Parallel to the investigation of novel biomarkers, such as high-sensitivity C-reactive protein, ongoing research has yielded improved metrics of known causative conditions. This evolution of traditional risk factors, heralded by measures such as ambulatory blood pressure, central hemodynamics, low density lipoprotein particle concentration, genetic testing, and "vascular age," may better address the detection gap in cardiovascular disease.

Beyond blood pressure: evidence for cardiovascular, cerebrovascular, and renal protective effects of renin-angiotensin system blockers

For patients with hypertension, effective control of blood pressure (BP) reduces cardiovascular (CV), and renal risk. Antihypertensive agents that offer benefits that extend beyond those associated with BP reduction alone, to include tissue protective effects and effects on the vasculature, may be of benefit for many patients with increased CV risk due to comorbidities or prior history of CV events. Renin-angiotensin system (RAS) blockers [angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs)] are guideline-recognized, highly effective antihypertensive agents that exert their BP-lowering action through different mechanisms at different levels of the RAS. Large-scale clinical studies suggest that small, between-treatment differences in BP lowering do not account for observed outcome differences between RAS blockers and other antihypertensive agents. Analysis of data from seminal clinical studies and meta-analyses identify that, controlling for effects on BP control, RAS blockers may be more effective than calcium channel blockers (CCBs) in reducing risk of myocardial infarction and congestive heart failure; ARBs may be more effective than either ACEIs or β blockers in stroke prevention; CCBs may be more effective than RAS blockers in stroke prevention; and ARBs may be more effective than β blockers in reducing left ventricular hypertrophy. This review considers the rationale and evidence for benefits of RAS blockade beyond BP lowering, and highlights the differences between ARBs and ACEIs, and between agents within these drug classes.

Correlations between prescription of anti-hypertensive medication and mortality due to stroke

Background

One of the most important risk factors for stroke is hypertension. A number of studies have attempted to identify the most effective anti-hypertensive therapeutic group for stroke prevention. Using an epidemiologic approach we aimed to find correlations based on Hungarian data on stroke-mortality and on prescription routine of anti-hypertensive therapeutics in three different counties, showing significant difference in stroke mortality.

Methods

We have used the official yearly reports on stroke-mortality for the period 2003-2008. Based on the significant differences in the change in mortality due to stroke three counties were selected: Baranya, Bekes and Hajdu-Bihar. The usage of antihypertensive therapeutic groups was analyzed. The correlation of stroke mortality difference and different antihypertensive treatment habits was analyzed by using normality test, time series analyses, correlation coefficient, paired samples test, one sample test and chi-square test.

Results

For the year 2003 stroke-mortality standardized with the county population number was highest in county Bekes, followed by county Baranya and county Hajdu-Bihar. For each year stroke mortality has shown significant (p < 0.0001) difference between the three counties and the ranking/order of the counties has been preserved over time. During the period of our study, an increase in the number of days of treatment was observed for most of the anti-hypertensive drugs listed. We have observed that the increased use of high-ceiling diuretics resulted in a mortality advantage, and the reduction in use of calcium channel blockers with direct cardiac effect had negative consequences.

Conclusions

The authors acknowledge that by limiting the study to three counties the findings cannot be generalized to the whole Hungarian population. Two trends can still be identified:

i) increased number of days of treatment (and therefore the probable use) of high-ceiling diuretics is associated with reduction in mortality due to stroke and its immediate complications; ii) reduction in the use of non-dihidropiridin CCBs does not seem justified, as their use appears to be advantageous in stroke prevention. Authors put emphasis on the importance of the adherence of the patients to the preventive therapies. Health care professionals could provide an important added value to the life long preventive therapies by improving the compliance of their patients, giving personalized care and advice.

A new dimension in hypertension management with the amlodipine/perindopril combination

Recent guidelines are consistent in acknowledging that most hypertensive patients need at least two drugs for optimal blood pressure (BP) control. Trial data are available to support the use of a renin-angiotensin system (RAS) blocker (ie, an angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker), plus a diuretic, a RAS blocker plus a calcium channel blocker (CCB), and a CCB plus a diuretic. The ACCOMPLISH trial demonstrated somewhat convincingly that an ACE inhibitor/CCB is superior to the same ACE inhibitor plus a thiazide. In the ASCOT trial, amlodipine/perindopril was superior to beta-blocker/thiazide in its effects on all major cardiovascular outcomes and new-onset diabetes. Further substudies of ASCOT provided plausible explanations for the benefits of amlodipine/perindopril strategy. In the CAFE substudy, amlodipine/perindopril was significantly more effective in the reduction of central BP as compared to atenolol/bendroflumethiazide, despite similar brachial BP reduction. More recently, analysis of long-term BP variability provided a further explanation for the reduction of cardiovascular events with amlodipine/perindopril in ASCOT. Thus, the combination of perindopril and amlodipine seems an ideal logical evidence-based pair of antihypertensive agents to select.

Effects of angiotensin-converting enzyme inhibitors beyond lowering blood pressure--are they important for doctors?

Large clinical trials and experimental studies have indicated that not all of the beneficial properties of angiotensin-converting enzyme inhibitors (ACE-Is) can be attributed to the lowering of blood pressure. The aim of this study was to assess doctors' opinions about the importance of the cardioprotective effects of ACE-Is beyond lowering blood pressure. The study participants (685 physicians) filled in a questionnaire testing doctors' knowledge of all of the therapeutic effects of ACE-Is not directly associated with lowering blood pressure and their clinical importance. In addition, each doctor filled in 20 questionnaires for subsequent patients treated with any ACE-I. Fifty-nine percent of the investigated physicians were aware of most of the therapeutic effects of ACE-Is. The most important therapeutic effects for the respondents were the following: reduction of peripheral resistance, inhibition of left ventricle hypertrophy, inhibition of vascular remodeling and atherosclerotic plaque stabilization. The most commonly prescribed ACE-Is were perindopril, lisinopril and chinalapril for inhibition of left ventricular hypertrophy and perindopril, ramipril and chinalapril for inhibition of arterial wall remodeling. The ACE-Is that were used to reduce peripheral vessel resistance included perindopril, lisinopril and trandolapril. Drugs used to stabilize the plaque included perindopril, lisinopril and cilazapril. The therapeutic effects of ACE-Is beyond lowering blood pressure were considered to be valid and important in daily clinical practice for the prevention of cardiovascular diseases and diabetic complications. The attribution of the effects of a particular ACE-I was not always in accordance with evidence-based medicine. The obtained treatment outcomes were attributed to the entire group of ACE-Is.

Rationale and design of the Newer Versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) trial

BACKGROUND

Sub-Saharan Africa experiences an epidemic surge in hypertension. Studies in African Americans led to the recommendation to initiate antihypertensive treatment in Blacks with a diuretic or a low-dose fixed combination including a diuretic. We mounted the Newer versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) trial to compare in native African patients a fixed combination of newer drugs, not involving a diuretic, with a combination of older drugs including a diuretic.

METHODS

Patients aged 30-69 years with uncomplicated hypertension (140-179/90-109 mmHg) and two or fewer associated risk factors are eligible. After a 4-week run-in period off treatment, 180 patients will be randomized to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg or amlodipine/valsartan 5/160 mg. To attain and maintain blood pressure below 140/90 mmHg during 6 months of follow-up, the doses of bisoprolol and amlodipine in the combination tablets will be increased to 10 mg/day with the possible addition of α-methyldopa or hydralazine. NOAAH is powered to demonstrate a 5-mmHg between-group difference in sitting systolic pressure with a two-sided p-value of 0.01 and 90% power. NOAAH is investigator-led and complies with the Helsinki declaration.

RESULTS

Six centers in four sub-Saharan countries started patient recruitment on September 1, 2010. On December 1, 195 patients were screened, 171 were enrolled, and 51 were randomized and followed up. The trial will be completed in the third quarter of 2011.

CONCLUSIONS

NOAAH (NCT01030458) is the first randomized multicenter trial of antihypertensive medications in hypertensive patients born and living in sub-Saharan Africa.

Primary stroke prevention and hypertension treatment: which is the first-line strategy?

Hypertension (HT) is considered the main classic vascular risk factor for stroke and the importance of lowering blood pressure (BP) is well established. However, not all the benefit of antihypertensive treatment is due to BP reduction per se, as the effect of reducing the risk of stroke differs among classes of antihypertensive agents. Extensive evidences support that angiotensin-converting enzyme inhibitors (ACEI), angiotensin II receptor blockers (ARB), dihydropyridine calcium channel blockers (CCB) and thiazide diuretics each reduced risk of stroke compared with placebo or no treatment. Therefore, when combination therapy is required, a combination of these antihypertensive classes represents a logical approach. Despite the efficacy of antihypertensive therapy a large proportion of the population, still has undiagnosed or inadequately treated HT, and remain at high risk of stroke. In primary stroke prevention current guidelines recommend a systolic/diastolic BP goal of <140/<90 mmHg in the general population and <130/80 mmHg in diabetics and in subjects with high cardiovascular risk and renal disease. The recent release in the market of the fixed-dose combination (FDC) of ACEI or ARB and CCB should provide a better control of BP. However to confirm the efficacy of the FDC in primary stroke prevention, clinical intervention trials are needed.

Pathophysiology, prevention and management of chronic kidney disease in the hypertensive patient with diabetes mellitus

The authors concisely review the main clinical issues arising in the management of the hypertensive patient with type 2 diabetes, in whom chronic kidney disease is prevalent and heralds increased cardiovascular morbidity and mortality. Special attention is paid to the clinical meaning, relevance and limits of albumin excretion and glomerular filtration rate, the two widely used markers of reduced kidney function during the course of chronic diseases like diabetes and hypertension. The main therapeutic strategies involving blood pressure and glycemic control, treatment of dyslipidemia and improvement of lifestyle are discussed from the viewpoint of a general practitioner dealing with the clinical complexity of these patients.

Are there pleiotropic effects of antihypertensive medications or is it all about the blood pressure in the patient with diabetes and hypertension?

Many small studies with varied surrogate end points and numerous preclinical data have suggested the likelihood of there being specific benefits that exceed simple blood pressure control with drug classes such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and calcium channel blockers, which may be particularly relevant to the patient with diabetes and hypertension. Large clinical trials, however, have provided only token support for this idea. Likewise, meta-analyses that have incorporated varied clinical trials, albeit with somewhat heterogeneous data, have not been particularly forthcoming in their support of this concept. In the patient with diabetes and hypertension, tight blood pressure control, more so than using a specific drug class, is the most important aspect of therapy.

Beneficial effects of combination of valsartan and amlodipine on salt-induced brain injury in hypertensive rats

The optimum antihypertensive treatment for prevention of hypertensive stroke has yet to be elucidated. This study was undertaken to examine the benefit of a combination of valsartan, an angiotensin II type 1 (AT1) receptor blocker, and amlodipine, a calcium channel blocker, in prevention of high-salt-induced brain injury in hypertensive rats. High-salt-loaded stroke-prone spontaneously hypertensive rats (SHRSPs) were given 1) vehicle, 2) valsartan (2 mg/kg/day), 3) amlodipine (2 mg/kg/day), or 4) a combination of valsartan and amlodipine for 4 weeks. The effects on brain injury were compared between all groups. High-salt loading in SHRSPs caused the reduction of cerebral blood flow (CBF), cerebral hypoxia, white matter lesions, glial activation, AT1 receptor up-regulation, endothelial nitric-oxide synthase (eNOS) uncoupling, inducible nitric-oxide synthase induction, and nitroxidative stress. Valsartan, independently of blood pressure, enhanced the protective effects of amlodipine against brain injury, white matter lesions, and glial activation in salt-loaded SHRSPs. These beneficial effects of valsartan added to amlodipine were associated with an additive improvement in CBF and brain hypoxia because of an additive improvement in cerebral arteriolar remodeling and vascular endothelial dysfunction. Furthermore, valsartan added to amlodipine enhanced the attenuation of cerebral nitroxidative stress through an additive suppression of eNOS uncoupling. Valsartan, independently of blood pressure, augmented the protective effects of amlodipine against brain injury in salt-loaded hypertensive rats through an improvement in brain circulation attributed to nitroxidative stress. Our results suggest that the combination of valsartan and amlodipine may be a promising strategy for the prevention of salt-related brain injury in hypertensive patients.

Survival with treated and well-controlled blood pressure: findings from a prospective cohort study

Aim

To compare survival and incident cardiovascular disease between normotensive, untreated hypertensive, treated and poorly-controlled hypertensive and treated and well-controlled hypertensive adults.

Methods and Results

Data from the British Regional Heart Study (men) and British Women's Heart and Health Study (women) were used (N = 6476). Blood pressure and treatment were assessed at baseline (1998–2001) when participants were aged 60–79 years and participants were followed up for a median of 8 years. Date and cause of death were obtained from death certificates and non-fatal cardiovascular disease events were obtained from repeat detailed medical record reviews. Of the whole cohort 52% of women and 49% of men had untreated hypertension and a further 22% and 18%, respectively, had poorly treated hypertension. Just 3% of women and 4% of men had treated and well controlled hypertension and 23% and 29%, respectively, were normotensive. Compared to normotensive individuals, incident cardiovascular disease (fatal and non-fatal) was increased in those with poorly-controlled hypertension (Hazard Ratio (HR): 1.88; 95%CI: 1.53, 2.30), those with untreated hypertension (HR 1.46; 95%CI 1.22, 1.75) and those who were well-controlled hypertension (HR 1.38; 95%CI 0.94, 2.03). Adjustment for baseline differences in mean blood pressure between the groups resulted in attenuation of the increased risk in the poorly-controlled (1.52 (1.18, 1.97) and untreated groups (1.21 (0.97, 1.52), but did not change the association in the well-controlled group. All-cause mortality was also increased in all three hypertension groups but estimates were imprecise with wide confidence intervals.

Conclusions

Half of women and men aged 60–79 in Britain had untreated hypertension and only a very small proportion of those with diagnosed and treated hypertension were well controlled. Those with hypertension, irrespective of whether this was treated and controlled or not, were at greater risk of future cardiovascular disease than those who are normotensive.