Add-on Amlodipine Improves Arterial Function and Structure in Hypertensive Patients Treated With an Angiotensin Receptor Blocker

Pharmacological interventions for asymptomatic carotid stenosis

BACKGROUND

Carotid artery stenosis is narrowing of the carotid arteries. Asymptomatic carotid stenosis is when this narrowing occurs in people without a history or symptoms of this disease. It is caused by atherosclerosis; that is, the build-up of fats, cholesterol, and other substances in and on the artery walls. Atherosclerosis is more likely to occur in people with several risk factors, such as diabetes, hypertension, hyperlipidaemia, and smoking. As this damage can develop without symptoms, the first symptom can be a fatal or disabling stroke, known as ischaemic stroke. Carotid stenosis leading to ischaemic stroke is most common in men older than 70 years. Ischaemic stroke is a worldwide public health problem.

OBJECTIVES

To assess the effects of pharmacological interventions for the treatment of asymptomatic carotid stenosis in preventing neurological impairment, ipsilateral major or disabling stroke, death, major bleeding, and other outcomes.

SEARCH METHODS

We searched the Cochrane Stroke Group trials register, CENTRAL, MEDLINE, Embase, two other databases, and three trials registers from their inception to 9 August 2022. We also checked the reference lists of any relevant systematic reviews identified and contacted specialists in the field for additional references to trials.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs), irrespective of publication status and language, comparing a pharmacological intervention to placebo, no treatment, or another pharmacological intervention for asymptomatic carotid stenosis.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Two review authors independently extracted the data and assessed the risk of bias of the trials. A third author resolved disagreements when necessary. We assessed the evidence certainty for key outcomes using GRADE.

MAIN RESULTS

We included 34 RCTs with 11,571 participants. Data for meta-analysis were available from only 22 studies with 6887 participants. The mean follow-up period was 2.5 years. None of the 34 included studies assessed neurological impairment and quality of life. Antiplatelet agent (acetylsalicylic acid) versus placebo Acetylsalicylic acid (1 study, 372 participants) may result in little to no difference in ipsilateral major or disabling stroke (risk ratio (RR) 1.08, 95% confidence interval (CI) 0.47 to 2.47), stroke-related mortality (RR 1.40, 95% CI 0.54 to 3.59), progression of carotid stenosis (RR 1.16, 95% CI 0.79 to 1.71), and adverse events (RR 0.81, 95% CI 0.41 to 1.59), compared to placebo (all low-certainty evidence). The effect of acetylsalicylic acid on major bleeding is very uncertain (RR 0.98, 95% CI 0.06 to 15.53; very low-certainty evidence). The study did not measure neurological impairment or quality of life. Antihypertensive agents (metoprolol and chlorthalidone) versus placebo The antihypertensive agent, metoprolol, may result in no difference in ipsilateral major or disabling stroke (RR 0.14, 95% CI 0.02 to1.16; 1 study, 793 participants) and stroke-related mortality (RR 0.57, 95% CI 0.17 to 1.94; 1 study, 793 participants) compared to placebo (both low-certainty evidence). However, chlorthalidone may slow the progression of carotid stenosis (RR 0.45, 95% CI 0.23 to 0.91; 1 study, 129 participants; low-certainty evidence) compared to placebo. Neither study measured neurological impairment, major bleeding, adverse events, or quality of life. Anticoagulant agent (warfarin) versus placebo The evidence is very uncertain about the effects of warfarin (1 study, 919 participants) on major bleeding (RR 1.19, 95% CI 0.97 to 1.46; very low-certainty evidence), but it may reduce adverse events (RR 0.89, 95% CI 0.81 to 0.99; low-certainty evidence) compared to placebo. The study did not measure neurological impairment, ipsilateral major or disabling stroke, stroke-related mortality, progression of carotid stenosis, or quality of life. Lipid-lowering agents (atorvastatin, fluvastatin, lovastatin, pravastatin, probucol, and rosuvastatin) versus placebo or no treatment Lipid-lowering agents may result in little to no difference in ipsilateral major or disabling stroke (atorvastatin, lovastatin, pravastatin, and rosuvastatin; RR 0.36, 95% CI 0.09 to 1.53; 5 studies, 2235 participants) stroke-related mortality (lovastatin and pravastatin; RR 0.25, 95% CI 0.03 to 2.29; 2 studies, 1366 participants), and adverse events (fluvastatin, lovastatin, pravastatin, probucol, and rosuvastatin; RR 0.76, 95% CI 0.53 to1.10; 7 studies, 3726 participants) compared to placebo or no treatment (all low-certainty evidence). The studies did not measure neurological impairment, major bleeding, progression of carotid stenosis, or quality of life.

AUTHORS' CONCLUSIONS

Although there is no high-certainty evidence to support pharmacological intervention, this does not mean that pharmacological treatments are ineffective in preventing ischaemic cerebral events, morbidity, and mortality. High-quality RCTs are needed to better inform the best medical treatment that may reduce the burden of carotid stenosis. In the interim, clinicians will have to use other sources of information.

Mineralocorticoid receptor antagonist treatment improved arterial stiffness in patients with primary aldosteronism: a cohort study compared with adrenalectomy

Background

Elevated arterial stiffness in patients with primary aldosteronism (PA) can be reversed after adrenalectomy; however, the effect of medical treatment with mineralocorticoid receptor antagonist (MRAs) is unknown.

Objectives

The aim of this study was to evaluate the effect of MRAs and compare both treatment strategies on arterial stiffness in PA patients.

Design

Prospective cohort study.

Methods

We prospectively enrolled PA patients from 2006 to 2019 who received either adrenalectomy or MRA treatment (spironolactone). We compared their baseline and 1-year post-treatment biochemistry characteristics and arterial pulse wave velocity (PWV) to verify the effects of treatment and related determinant factors.

Results

A total 459 PA patients were enrolled. After 1:1 propensity score matching for age, sex and blood pressure (BP), each group had 176 patients. The major determinant factors of baseline PWV were age and baseline BP. The adrenalectomy group had greater improvements in BP, serum potassium level, plasma aldosterone concentration, and aldosterone-to-renin ratio. The MRA group had a significant improvement in PWV after 1 year of treatment (1706.2 ± 340.05 to 1613.6 ± 349.51 cm/s, p < 0.001). There were no significant differences in post-treatment PWV (p = 0.173) and improvement in PWV (p = 0.579) between the adrenalectomy and MRA groups. The determinant factors for an improvement in PWV after treatment were hypertension duration, baseline PWV, and the decrease in BP.

Conclusion

The PA patients who received medical treatment with MRAs had a significant improvement in arterial stiffness. There was no significant difference in the improvement in arterial stiffness between the two treatment strategies.

Electrocardiographic measures of left ventricular hypertrophy in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

Left ventricular hypertrophy (LVH) predicts cardiovascular risk in hypertensive patients. We analyzed baseline/follow-up electrocardiographies in 26,376 Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial participants randomized to amlodipine (A), lisinopril (L), or chlorthalidone (C). Prevalent/incident LVH was examined using continuous and categorical classifications of Cornell voltage. At 2 and 4 years, prevalence of LVH in the C group (5.57%; 6.14%) was not statistically different from A group (2 years: 5.47%; P = .806, 4 years: 6.54%; P = .857) or L group (2 years: 5.64%; P = .857, 4 years: 6.50%; P = .430). Incident LVH followed similarly, with no difference at 2 years for C (2.99%) compared to A (2.57%; P = .173) or L (3.16%; P = .605) and at 4 years (C = 3.52%, A = 3.29%, L = 3.71%; P = .521 C vs. A, P = .618 C vs. L). Mean Cornell voltage decreased comparably across treatment groups (Δ baseline, 2 years = +3 to -27 μV, analysis of variance P = .8612; 4 years = +10 to -17 μV, analysis of variance P = .9692). We conclude that risk reductions associated with C treatment in secondary end points of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial cannot be attributed to differential improvements in electrocardiography LVH.

Effect of visit-to-visit blood pressure variability on cardiovascular events in patients with coronary artery disease and well-controlled blood pressure

This post hoc analysis of CAMELOT and PREVENT analyzed the impact of blood pressure variability (BPV, assessed as within-subject standard deviation of SBP from 12 weeks onward) on the incidence of major adverse cardiovascular events (MACE, defined according to original studies). Patients (n = 1677 CAMELOT; n = 776 PREVENT) were stratified by BPV quartile. Regardless of study, BPV was significantly lower for amlodipine versus other treatments. In CAMELOT, a significant association between BPV quartile and MACE was observed with amlodipine treatment. Significant associations between BPV quartile and MACE were observed for both studies, when analyzed overall (adjusting for treatment). In CAMELOT, with amlodipine treatment, an increased risk for MACE was observed with high (BPV ≥ Q3) versus low BPV (< Q1; adjusting for characteristics and risk factors). In both studies, increased risk for MACE was observed for BPV ≥ Q3 versus BPV < Q1 (analyzed overall, adjusting for treatment and covariates). For both studies, BPV, but not mean SBP, was associated with cardiovascular events. BPV was associated with cardiovascular outcomes in patients with CAD and well-controlled BP.

Blood Pressure Lowering Medication, Visit-to-Visit Blood Pressure Variability, and Cognitive Function in Old Age

BACKGROUND

Visit-to-visit blood pressure (BP) variability is associated with cognitive impairment. We assessed to what extent the association between BP variability and cognitive impairment is mediated by the association of BP lowering medication (BPLM) with both BP variability and cognition.

METHODS

We studied 5,606 participants from the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). BP was measured every 3 months during 3.2 years; BP variability was defined as the SD of BP measurements during follow-up. Cognitive function was assessed at baseline and during follow-up using the Stroop test, Letter-Digit Coding test, and immediate and delayed Picture-Word Learning tests. Multivariate regression models were used with and without adjustments for BPLM to calculate the percentage to which BPLM mediated the association between BP variability and cognition.

RESULTS

Participants taking calcium antagonists had a higher score in baseline Letter-Digit Coding test (mean difference (95% confidence interval (CI) 0.45 (0.06; 0.88). Participants taking beta-blockers had a steeper decline in Stroop test (additional change per year (95% CI) 0.40 (0.09; 0.70) and Letter-Digit Coding test (0.08 (-0.15; -0.02)). Furthermore, a steeper decline in Stroop test was found in participants taking renin-angiotensin system (RAS) inhibitors (0.50 (0.16; 0.85). Systolic BP variability was higher in participants taking beta-blockers and RAS inhibitors (mean difference in systolic BP variability in mm Hg (95% CI) 0.75 (0.45; 1.04) and 1.37 (1.04; 1.71) respectively). Participants taking diuretics, calcium antagonists, and RAS inhibitors had a higher diastolic BP variability (mean difference in diastolic BP variability in mm Hg (95% CI) 0.27 (0.04; 0.49), 0.37 (0.12; 0.62) and 0.65 (0.37; 0.93) SD, respectively). Beta estimates remained essentially the same when we adjusted for BPLM in the association of BP variability with cognitive function.

CONCLUSIONS

The association between BP variability and cognitive impairment was not mediated by BPLM.

Long-term prognostic implications of visit-to-visit blood pressure variability in patients with ischemic stroke

BACKGROUND

Blood pressure (BP) variability (BPV) is a novel risk factor for the development of atherosclerotic diseases. High BPV has recently been shown to predict all-cause and cardiovascular mortality in patients with lacunar infarct. Whether BPV has prognostic implications in patients with ischemic stroke subtypes, other than those due to small-vessel occlusion, remains uncertain.

METHODS

We prospectively followed up the clinical outcome of 632 consecutive ischemic stroke patients without atrial fibrillation. The average BP and BPV, as determined by the coefficient of variation of the systolic and diastolic BP, were recorded during a mean 12 ± 6 outpatient clinic visits.

RESULTS

The average age of the population was 71 ± 11 years. After a mean of 76 ± 18 months of follow-up, 161 patients died (26%); 35% (n = 56 of 161) of these deaths were due to cardiovascular causes. Sixteen percent and 5% developed recurrent stroke and acute coronary syndrome (ACS), respectively. After adjusting for mean systolic BP and confounding variables, patients with high systolic BPV were at significantly greater risk of cardiovascular mortality (hazards ratio (HR) = 2.36; 95% confidence interval (CI) = 1.02-5.49; P < 0.05). High systolic BPV also predicted all-cause mortality after adjusting for mean systolic BP (HR = 1.79; 95% CI = 1.16-2.75; P < 0.05). There was no association between systolic BPV and nonfatal recurrent stroke or nonfatal ACS. Raised diastolic BPV did not predict recurrent nonfatal stroke, nonfatal ACS, or mortality.

CONCLUSIONS

Visit-to-visit systolic BPV predicts long-term all-cause and cardiovascular mortality in patients with ischemic stroke without atrial fibrillation, independent of other conventional risk factors, including average BP control.

Visit-to-visit blood pressure variability as a prognostic marker in patients with cardiovascular and cerebrovascular diseases--relationships and comparisons with vascular markers of atherosclerosis

BACKGROUND

Visit-to-visit blood pressure variability (BPV) is a simple surrogate marker for the development of atherosclerotic diseases, cardiovascular and all-cause mortality. Nevertheless, the relative prognostic value of BPV in comparison with other established vascular assessments remain uncertain.

METHODS

We prospectively followed-up 656 high-risk patients with diabetes or established cardiovascular or cerebrovascular diseases for the occurrence of major adverse cardiovascular events (MACEs). Baseline brachial endothelial function, carotid intima-media thickness (IMT) and plaque burden, ankle-brachial index and arterial stiffness were determined. Visit-to-visit BPV were recorded during a mean 18 ± 9 outpatient clinic visits.

RESULTS

After a mean 81 ± 12 month's follow-up, 123 patients (19%) developed MACEs. Patients who developed a MACE had significantly higher systolic BPV, more severe endothelial function, arterial stiffness and systemic atherosclerotic burden compared to patients who did not develop a MACE (all P<0.01). BPV significantly correlated with all of the vascular assessments (P<0.01). A high carotid IMT had the greatest prognostic value in predicting development of a MACE (area under receiver operating characteristic curve (AUC) 0.69 ± 0.03, P<0.01). A high BPV also had moderate prognostic value in prediction of MACE (AUC 0.65 ± 0.03, P<0.01). After adjustment of confounding factors, a high BPV remained a significant independent predictor of MACE (hazards ratio 1.67, 95% confidence interval 1.14-2.43, P<0.01).

CONCLUSIONS

Compared with established surrogate markers of atherosclerosis, visit-to-visit BPV provides similar prognostic information and may represent a new and simple marker for adverse outcomes in patients with vascular diseases.

Effect of chlorthalidone, amlodipine, and lisinopril on visit-to-visit variability of blood pressure: results from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

Few randomized trials have compared visit-to-visit variability (VVV) of systolic blood pressure (SBP) across drug classes. The authors compared VVV of SBP among 24,004 participants randomized to chlorthalidone, amlodipine, or lisinopril in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). VVV of SBP was calculated across 5 to 7 visits occurring 6 to 28 months following randomization. The standard deviation (SD) of SBP was 10.6 (SD=5.0), 10.5 (SD=4.9), and 12.2 (SD=5.8) for participants randomized to chlorthalidone, amlodipine, and lisinopril, respectively. After multivariable adjustment including mean SBP across visits and compared with participants randomized to chlorthalidone, participants randomized to amlodipine had a 0.36 (standard error [SE]: 0.07) lower SD of SBP and participants randomized to lisinopril had a 0.77 (SE=0.08) higher SD of SBP. Results were consistent using other VVV of SBP metrics. These data suggest chlorthalidone and amlodipine are associated with lower VVV of SBP than lisinopril.

Elevated LDL-C combined with hypertension worsens subclinical vascular impairment and cognitive function

Hypertension and dyslipidemia belong to the most prevalent modifiable risk factors for cerebrovascular and cardiovascular diseases. Hereby, we aimed to examine the combined effects of newly diagnosed hypertension and hyperlipidemia on the characteristics of the arterial wall and on cognitive function. We examined 72 hypertensive and 85 apparently healthy individuals. Based on serum lipid levels, four subgroups were created ranging from normotensive-normolipidemic to hypertensive-hyperlipidemic subjects. Carotid intima-media thickness (IMT), arterial stiffness, and cognitive function were assessed. IMT of controls was the lowest, whereas that of patients with both risk factors the highest. Stiffness parameters increased when both risk factors were present, whereas subjects with only one risk factor exhibited intermediate values. Hypertensive patients performed worse when memory, attention, reaction time, and trait anxiety were assessed. Significant worsening of IMT, arterial stiffness, and sum of neuropsychological scores was observed along with increasing mean arterial pressure. Generally, hyperlipidemia combining with hypertension resulted in further worsening of all examined parameters. Subclinical changes of the vascular wall and cognitive performance are already present in recently diagnosed hypertensive patients. Combination of hyperlipidemia and hypertension results in more severe impairments, therefore, early and intensive treatment may be crucial to prevent further deterioration.

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.

Visit-to-visit systolic blood pressure variability predicts all-cause and cardiovascular mortality after lacunar infarct

BACKGROUND AND PURPOSE

Both blood pressure (BP) and its variability (BPV) are established risk factors for development of atherosclerotic disease and are associated with an increased risk for cardiovascular and all-cause mortality. The prognostic implications of outpatient clinic visit-to-visit BPV amongst patients with lacunar infarction are nevertheless unknown.

METHODS

The clinical outcome of 281 patients with lacunar infarction was prospectively followed up. The average BP and BPV, as determined by the standard deviation of the systolic and diastolic BP, were recorded during a mean 13 ± 6 outpatient clinic visits.

RESULTS

The mean age of the population was 70 ± 10 years. After a mean 78 ± 18 months follow-up, 65 patients died (23%), 31% (20/65) due to cardiovascular causes; 14% and 7% developed recurrent stroke and acute coronary syndrome. After adjusting for age, sex, mean systolic and diastolic BP, cardiovascular risk factors and comorbidities, patients with a systolic BPV of the third tertile had significantly higher risk of all-cause mortality [hazard ratio (HR) 1.97, 95% confidence interval (CI) 1.02-3.80, P = 0.04) and cardiovascular mortality (HR 7.64, 95% CI 1.65-35.41, P < 0.01) than those with systolic BPV of the first tertile. Nevertheless, systolic BPV did not predict recurrent stroke or acute coronary syndrome. Diastolic BPV did not predict various adverse clinical outcomes.

CONCLUSIONS

Visit-to-visit systolic BPV predicts long-term all-cause and cardiovascular mortality after lacunar infarct, independent of conventional risk factors including average BP control.

Effects of antihypertensive drugs on central blood pressure in humans: a preliminary observation

BACKGROUND

Central blood pressure (BP) is considered a better predictor of cardiovascular events than brachial BP. Modifications of central, beyond brachial BP, can be assessed by pressure amplification, a potential new cardiovascular risk factor. Comparison between drugs' effect on central hemodynamics has been poorly studied. Our aim was to assess the hemodynamic effect of a 12-week treatment with amlodipine 5mg, or candesartan 8mg, or indapamide sustained-release 1.5mg, in comparison with placebo.

METHODS

We analyzed 145 out-patients with essential hypertension in primary prevention enrolled in the Natrilix SR Versus Candesartan and Amlodipine in the Reduction of Systolic Blood Pressure in Hypertensive Patients (X-CELLENT) study, a multicenter, randomized, double-blinded, placebo-controlled trial. Arterial stiffness, central BP, pressure amplification, and wave reflection were measured by applanation tonometry.

RESULTS

Baseline characteristics of patients were homogeneous between groups. After treatment, we found that active drugs produced similar reduction of both central and peripheral BPs, with no significant interdrug differences (all P < 0.05; excluded peripheral pulse pressure, compared with placebo). Second, amlodipine (1.9% ± 15.3%), candesartan (3.0% ± 14.6%) and indapamide (4.1% ± 14.4%) all increased pulse pressure amplification, but only indapamide was statistically different from placebo (P = 0.02). Finally, no significant changes were observed on pulse wave velocity, heart rate, and augmentation index.

CONCLUSIONS

The 3 antihypertensive drugs similarly reduced peripheral and central BP, as compared with placebo, but a significant increase in pulse pressure amplification was obtained only with indapamide, independently of arterial stiffness modifications.

REGISTRATION NUMBER

3283161 by BIOPHARMA.

Olmesartan/amlodipine: blood pressure lowering and beyond in special populations

Clinical studies and population-based analyses show that in patients with hypertension, the majority cannot control their blood pressure (BP) by treatment with a single antihypertensive agent. Combining agents from different antihypertensive classes with complementary modes of action significantly increases efficacy and is a treatment strategy recommended by European treatment guidelines, particularly in patients at high cardiovascular risk. The combinations of antihypertensive agents recommended by the European guidelines include an angiotensin receptor blocker (ARB) with a calcium channel blocker (CCB). The single-pill combination formulation of the ARB olmesartan medoxomil plus the CCB amlodipine is an effective and well-tolerated treatment that provides greater blood pressure lowering and control than the component monotherapies and favours compliance by not increasing pill burden. Importantly, the efficacy and tolerability of olmesartan plus amlodipine is not affected by age, gender, hypertension severity, diabetes status, race or body mass index. Additional blood pressure lowering effects are observed with stepwise uptitration of olmesartan plus amlodipine with or without hydrochlorothiazide, with more patients achieving blood pressure goals. In addition, olmesartan plus amlodipine has demonstrated effects beyond BP lowering by showing beneficial effects on markers of inflammation, endothelial dysfunction and oxidative stress, as well as metabolic improvements and a reduction in new-onset diabetes incidence in hypertensive patients with metabolic syndrome.

Low achieved diastolic pressure in tightly controlled mid-older hypertensive subjects is associated with favorable arterial properties

Low diastolic blood pressure (DBP) is commonly seen in well-controlled hypertensive subjects. We evaluated arterial properties in 53 hypertensive subjects with low on-treatment DBP (<70 mm Hg; LODP), 54 subjects with normal BP and spontaneously low DBP (SLDP), and 52 treated hypertensive subjects with DBP ≥70 mm Hg (HNDP). The two measures of large artery rigidity, pulse wave velocity and augmentation index, were similar in LODP and SLDP groups. In contrast, the HNDP group had higher PWV and the lowest large and small artery compliance in comparison with all other groups. Low on-treatment DBP is associated with favorable arterial properties in mid-older hypertensive patients.

Do all antihypertensive drugs improve carotid intima-media thickness? A network meta-analysis of randomized controlled trials

The many clinical trials investigating the effect of various antihypertensive drugs on carotid intima-media thickness (CIMT) produced conflicting results. We used meta-analysis to evaluate CIMT changes and network meta-analysis to rank drugs according to the magnitude of these changes. We identified 31 randomized controlled trials listed in three databases as of January 2008. Using a random-effects model, we found a significant CIMT decrease with antihypertensive drugs compared to placebo (-0.10 [-0.16; -0.04]). Overall effect sizes vs. placebo were significant for angiotensin-converting enzyme (ACE) inhibitors (-0.08 [-0.14; -0.02]), and a trend was found for beta-blockers (-0.09 [-0.19; 0.01]). The data did not allow other direct comparisons vs. placebo. Significant benefits were found for calcium-channel blockers (CCBs) compared to both ACE inhibitors (0.37 [0.20; 0.54]), as well as for angiotensin II receptor blockers (ARBs) compared to beta-blockers (0.42 [0.29; 0.55]). Diuretics were less efficient than CCBs (-0.09 [-0.16; -0.02]). Indirect comparisons with network meta-analysis showed significant effects of CCBs and ARBs vs. placebo (both P < 0.05) and vs. diuretics (both P < 0.001). The CIMT decrease with ACE inhibitors and beta-blockers was greater than with diuretics (both P < 0.05) but was not different from the placebo effect. In subgroup analyses, significant benefits occurred with lower baseline CIMT values and shorter treatment durations but were unrelated to the size of the blood pressure decrease. In conclusion, among antihypertensive drugs, CCBs and ARBs have the greatest effect on CIMT.

The role of ambulatory blood pressure monitoring compared with clinic and home blood pressure measures in evaluating moderate versus intensive treatment of hypertension with amlodipine/valsartan for patients uncontrolled on angiotensin receptor blocker monotherapy

OBJECTIVES

Ambulatory blood pressure monitoring (ABPM) has greater predictive value than office blood pressure (BP) with respect to hypertension-related target-organ damage and morbidity. ABPM in a subset of 80 patients from the Exforge Target Achievement trial (N=728) was used to compare the efficacy of intensive-treatment and moderate-treatment regimens of amlodipine/valsartan, and to determine whether treatment differences could be better assessed with ABPM than with office or home BP. Home BP was measured on the morning of clinic visits to minimize differences that timing might have on home versus office BP measures.

METHODS

A 12-week randomized, double-blind study in which hypertensive patients earlier uncontrolled (mean sitting systolic BP≥150 and <200 mmHg) on angiotensin receptor blocker monotherapy (other than valsartan) after 28 days or more (N=728) were randomized to amlodipine/valsartan treatment [10/320 mg (intensive) or 5/160 mg (moderate)]. Treatment-naive patients (in previous 28 days) or patients who failed on a nonangiotensin receptor blocker agent underwent a 28-day run-in period with a 20-mg or 40-mg dose of olmesartan, respectively.

RESULTS

Significantly greater 24-h ABP reductions from baseline to week 4 (primary time point) were observed with intensive versus moderate treatment (least-square mean systolic/diastolic BP reduction of -16.2/-10.1 vs. -9.5/-6.5 mmHg; P=0.0024/P=0.010 for least-square mean difference). Similarly, a significantly greater proportion of patients receiving an intensive treatment achieved ambulatory BP goal (<130/80 mmHg) at week 4 than did those receiving a moderate treatment (P=0.040). Treatment-group differences did not reach statistical significance for these end points when measured by office and home BP.

CONCLUSION

In this first randomized trial evaluating the effects of intensive versus moderate dosing of the combination of amlodipine/valsartan, our data suggest that ABPM was a better method for assessing between-treatment differences than clinic or home BP recordings, although measurement of home BP as a single recording was a limitation of our trial.

The role of Angiotensin receptor blocker and calcium channel blocker combination therapy in treating hypertension: focus on recent studies

Hypertension remains a significant health problem, affecting approximately 30% of the US population. Of these, only 36.8% have BP controlled to recommended levels of <140/90 mmHg for uncomplicated hypertension and <130/80 mmHg for patients with diabetes mellitus or renal disease. For those with uncontrolled hypertension, the risk of diabetes, renal disease, stroke, and cardiovascular disease is increased. Therapeutic options for the treatment of hypertension include several major classes of drugs: diuretics, β-adrenoceptor antagonists (β-blockers), ACE inhibitors, angiotensin II type 1 receptor antagonists (angiotensin receptor blockers [ARBs]), renin inhibitors, calcium channel blockers, and central sympatholytics, alone or in combination. Guidelines recommend thiazide diuretics as preferred first-line monotherapy. However, only 50% of patients will respond adequately to this therapy and the rest will require two or more antihypertensive agents to achieve BP goals. Clinical evidence demonstrates that some drugs have advantages when used in combination rather than as monotherapy. Drugs that block the renin-angiotensin-aldosterone system not only provide BP control but may also provide vascular protection and are metabolically neutral. This is a concise review of the safety and efficacy of ARBs in combination with amlodipine for the treatment of hypertension, with focus on the telmisartan-amlodipine combination. A MEDLINE search of the English literature from 2006 to 2009 of amlodipine in combination with ARBs revealed six publications, which are included in this review.

Combinations of inhibitors of the renin-angiotensin system with calcium channel blockers for the treatment of hypertension: focus on perindopril/amlodipine

BACKGROUND

Combination antihypertensive therapy with an inhibitor of the renin-angiotensin system (RAS) and a calcium channel blocker (CCB) is a rational approach to achieve blood pressure (BP) goals in patients with hypertension, and may provide additional cardiovascular protection compared to other strategies in special populations. This article reviews the rationale for, and evidence supporting, the use of newer fixed-dose combinations of RAS inhibitors and CCBs, with particular emphasis on perindopril/amlodipine.

METHODS

A literature search was performed in Medline and EMBASE databases to identify articles published up to May 2010 describing the impact of combination treatment with angiotensin receptor blocker (ARB)/CCB or angiotensin-converting enzyme (ACE) inhibitor/CCB based antihypertensive strategies on BP or clinical outcomes.

FINDINGS

A substantial body of evidence supports the BP-lowering efficacy of RAS inhibitor/CCB combination therapy in patients with hypertension. RAS inhibitors and CCBs represent two different and complementary mechanisms of actions; their use in combination is associated with effective BP lowering with favourable tolerability and fewer adverse metabolic effects than some other combination therapies. Currently, intervention studies demonstrating the impact of ARB/CCB combinations on cardiovascular mortality and morbidity are lacking. However, evidence from large outcome trials supports the use of ACE inhibitor/CCB combinations for reducing the risk of cardiovascular and renal events, particularly in high-risk patients. There is also evidence that the benefits of ACE inhibitor/CCB combinations may extend beyond those solely associated with brachial BP lowering, by an additional impact on central BP haemodynamics.

CONCLUSIONS

RAS inhibitor/CCB combination therapy is an effective antihypertensive therapy. Strong evidence supports the antihypertensive efficacy of ACE inhibitor/CCB combinations with cardioprotective and renoprotective properties. In particular, evidence suggests that fixed-dose perindopril/amlodipine effectively decreases BP and currently is the only RAS inhibitor/CCB combination proven to decrease all-cause and cardiovascular mortality as well as major cardiovascular events, and thus is a valuable option for the management of hypertension, especially in high-risk patients.

Limitations of the usual blood-pressure hypothesis and importance of variability, instability, and episodic hypertension

Although hypertension is the most prevalent treatable vascular risk factor, how it causes end-organ damage and vascular events is poorly understood. Yet, a widespread belief exists that underlying usual blood pressure can alone account for all blood-pressure-related risk of vascular events and for the benefits of antihypertensive drugs, and this notion has come to underpin all major clinical guidelines on diagnosis and treatment of hypertension. Other potentially informative measures, such as variability in clinic blood pressure or maximum blood pressure reached, have been neglected, and effects of antihypertensive drugs on such measures are largely unknown. Clinical guidelines recommend that episodic hypertension is not treated, and the potential risks of residual variability in blood pressure in treated hypertensive patients have been ignored. This Review discusses shortcomings of the usual blood-pressure hypothesis, provides background to accompanying reports on the importance of blood-pressure variability in prediction of risk of vascular events and in accounting for benefits of antihypertensive drugs, and draws attention to clinical implications and directions for future research.

Effects of antihypertensive-drug class on interindividual variation in blood pressure and risk of stroke: a systematic review and meta-analysis

INTRODUCTION

Unexplained differences between classes of antihypertensive drugs in their effectiveness in preventing stroke might be due to class effects on intraindividual variability in blood pressure. We did a systematic review to assess any such effects in randomised controlled trials.

METHODS

Baseline and follow-up data for mean (SD) of systolic blood pressure (SBP) were extracted from trial reports. Effect of treatment on interindividual variance (SD2) in blood pressure (a surrogate for within-individual variability), expressed as the ratio of the variances (VR), was related to effects on clinical outcomes. Pooled estimates were derived by use of random-effects meta-analysis.

FINDINGS

Mean (SD) SBP at follow-up was reported in 389 (28%) of 1372 eligible trials. There was substantial heterogeneity between trials in VR (p<1 x 10(-40)), 68% of which was attributable to allocated drug class. Compared with other drugs, interindividual variation in SBP was reduced by calcium-channel blockers (VR 0.81, 95% CI 0.76-0.86, p<0.0001) and non-loop diuretic drugs (0.87, 0.79-0.96, p=0.007), and increased by angiotensin-converting enzyme (ACE) inhibitors (1.08, 1.02-1.15, p=0.008), angiotensin-receptor blockers (1.16, 1.07-1.25, p=0.0002), and beta blockers (1.17, 1.07-1.28, p=0.0007). Compared with placebo only, interindividual variation in SBP was reduced the most by calcium-channel blockers (0.76, 0.67-0.85, p<0.0001). Effects were consistent in parallel group and crossover design trials, and in analyses of dose-response. Across all trials, effects of treatment on VR of SBP (r2=0.372, p=0.0006) and on mean SBP (r2=0.328, p=0.0015) accounted for effects on stroke risk (eg, odds ratio 0.79, 0.71-0.87, p<0.0001, for VR< or =0.80), and both remained significant in a combined model.

INTERPRETATION

Drug-class effects on interindividual variation in blood pressure can account for differences in effects of antihypertensive drugs on risk of stroke independently of effects on mean SBP.

FUNDING

None.

Improving vascular function in hypertension: potential benefits of combination therapy with amlodipine and renin-angiotensin-aldosterone system blockers

Hypertension is characterized by endothelial dysfunction and increased risk for adverse cardiovascular outcomes. In addition to lowering blood pressure, the calcium-channel blocker amlodipine and blockers of the renin-angiotensin-aldosterone system (angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers) may further reduce cardiovascular risk by improving endothelial function when used alone or in combination. In fact, the beneficial effects of the combination of amlodipine and a renin-angiotensin-aldosterone system blocker on endothelial function have been found to be greater than the effect of either drug alone, likely due to additive effects on nitric oxide activity. This review summarizes the observed effects of these agents on endothelial function and the complementary mechanisms by which they act, thus providing rationale (beyond blood pressure benefits) for their use in combination.

Carotid intima-media thickness measurements: techniques and clinical relevance

Atherosclerosis is a systemic disease that is responsible for most cardiovascular events and stroke. Epidemiologic studies and intervention trials based on the incidence of acute vascular disease end points require years of follow-up, the participation of large populations, or both. As a consequence, such studies consume considerable time and financial resources. The use of surrogate markers, therefore, is of paramount relevance because it allows researchers to have reliable data in less time and from reduced populations. Intima-media thickness (IMT) measured by B-mode ultrasound is the most studied surrogate marker and has been validated by official medical agencies. In this article, we review the most important technical considerations related to its measurement and highlight issues that should be systematically addressed in IMT-related studies. In summary, the use of IMT as an end point in clinical studies is of great value, but several technical limitations might jeopardize its interpretation.

Comparison of renal and vascular protective effects between telmisartan and amlodipine in hypertensive patients with chronic kidney disease with mild renal insufficiency

The present study was conducted to compare the renal and vascular protective effects of telmisartan and amlodipine in untreated hypertensive chronic kidney disease (CKD) patients with moderate renal insufficiency. Thirty hypertensive CKD patients were randomly assigned to receive telmisartan 40 mg (n = 15) or amlodipine 5 mg (n = 15) once daily for 12 months. Changes in blood pressure, serum creatinine, 24-h creatinine clearance (Ccr), proteinuria, brachial-ankle pulse wave velocity (baPWV), intima-media thickness (IMT), plasma interleukin-6 (IL-6), plasma matrix metalloproteinase (MMP)-9 and lipid profiles were monitored in all patients. Before treatment, there were no significant differences in these parameters between the telmisartan and amlodipine groups. Over the 12 month observation period, blood pressure decreased equally in both groups. However, serum creatinine, proteinuria, baPWV, IMT, plasma levels of IL-6 and MMP-9 and total cholesterol decreased and 24-h Ccr increased more strikingly in the telmisartan group than the amlodipine group. These data suggest that telmisartan is more effective than amlodipine for protecting renovascular functions, and potentially for ameliorating atherosclerosis, in hypertensive CKD patients with moderate renal insufficiency.

Cilnidipine and Telmisartan Similarly Improves Vascular Damage in Hypertensive Patients

This study was designed to compare the effects of 12-month blood pressure (BP) control using cilnidipine and telmisartan on vascular damage in untreated hypertensive patients. One hundred patients were randomly assigned to either a cilnidipine group or a telmisartan group. The extent of vascular damage was assessed before and after treatment by measuring urinary albumin excretion (UAE), pulse wave velocity (PWV), and intima-media thickness (IMT) of the carotid arteries in each patient. Both drugs similarly decreased BP without altering plasma markers for oxidative stress or inflammation. Both UAE and PWV were significantly improved in both groups, but IMT was significantly reduced only in the cilnidipine group. Multiple regression analyses suggested that the UAE may have decreased as a result of a reduction in intraglomerular pressure caused by telmisartan or by efferent arteriolar dilation caused by cilnidipine. In addition, the PWV may have decreased as a result of the improvement in lipid metabolism caused by telmisartan or the reduction in plasma levels of aldosterone caused by cilnidipine. However, the analyses could not identify any definitive causal relationships or suggest the mechanism responsible for the improvement in IMT caused by cilnidipine. Thus, telmisartan and cilnidipine have unique properties for inhibiting vascular complications.