Randomized, placebo-controlled trial of the angiotensin-converting enzyme inhibitor, ramipril, in patients with coronary or other occlusive arterial disease. PART-2 Collaborative Research Group. Prevention of Atherosclerosis with Ramipril

Effects of renin-angiotensin-aldosterone-system inhibitors on coronary atherosclerotic plaques: The PARADIGM registry

BACKGROUND AND AIMS

Inhibition of Renin-Angiotensin-Aldosterone-System (RAAS) has been hypothesized to improve endothelial function and reduce plaque inflammation, however, their impact on the progression of coronary atherosclerosis is unclear. We aim to study the effects of RAAS inhibitor on plaque progression and composition assessed by serial coronary CT angiography (CCTA).

METHODS

We performed a prospective, multinational study consisting of a registry of patients without history of CAD, who underwent serial CCTAs. Patients using RAAS inhibitors were propensity matched to RAAS inhibitor naïve patients based on clinical and CCTA characteristics at baseline. Atherosclerotic plaques in CCTAs were quantitatively analyzed for percent atheroma volume (PAV) according to plaque composition. Interactions between RAAS inhibitor use and baseline PAV on plaque progression were assessed in the unmatched cohort using a multivariate linear regression model.

RESULTS

Of 1248 patients from the registry, 299 RAAS inhibitor taking patients were matched to 299 RAAS inhibitor naïve patients. Over a mean interval of 3.9 years, there was no significant difference in annual progression of total PAV between RAAS inhibitor naïve vs taking patients (0.75 vs 0.79%/year, p = 0.66). With interaction testing in the unmatched cohort, however, RAAS inhibitor use was significantly associated with lower non-calcified plaque progression (Beta coefficient -0.100, adjusted p = 0.038) with higher levels of baseline PAV.

CONCLUSIONS

The use of RAAS inhibitors over a period of nearly 4 years did not significantly impact on total atherosclerotic plaque progression or various plaque components. However, interaction testing to assess the differential effect of RAAS inhibition based on baseline PAV suggested a significant decrease in progression of non-calcified plaque in patients with a higher burden of baseline atherosclerosis, which should be considered hypothesis generating.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for adults with early (stage 1 to 3) non-diabetic chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a long-term condition that occurs as a result of damage to the kidneys. Early recognition of CKD is becoming increasingly common due to widespread laboratory estimated glomerular filtration rate (eGFR) reporting, raised clinical awareness, and international adoption of the Kidney Disease Improving Global Outcomes (KDIGO) classifications. Early recognition and management of CKD affords the opportunity to prepare for progressive kidney impairment and impending kidney replacement therapy and for intervention to reduce the risk of progression and cardiovascular disease. Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) are two classes of antihypertensive drugs that act on the renin-angiotensin-aldosterone system. Beneficial effects of ACEi and ARB on kidney outcomes and survival in people with a wide range of severity of kidney impairment have been reported; however, their effectiveness in the subgroup of people with early CKD (stage 1 to 3) is less certain. This is an update of a review that was last published in 2011.

OBJECTIVES

To evaluate the benefits and harms of ACEi and ARB or both in the management of people with early (stage 1 to 3) CKD who do not have diabetes mellitus (DM).

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 6 July 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and Embase, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) reporting the effect of ACEi or ARB in people with early (stage 1 to 3) CKD who did not have DM were selected for inclusion. Only studies of at least four weeks duration were selected. Authors independently assessed the retrieved titles and abstracts and, where necessary, the full text to determine which satisfied the inclusion criteria.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out by two authors independently, using a standard data extraction form. The methodological quality of included studies was assessed using the Cochrane risk of bias tool. Data entry was carried out by one author and cross-checked by another. When more than one study reported similar outcomes, data were pooled using the random-effects model. Heterogeneity was analysed using a Chi² test and the I² test. Results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach MAIN RESULTS: Six studies randomising 9379 participants with CKD stages 1 to 3 (without DM) met our inclusion criteria. Participants were adults with hypertension; 79% were male from China, Europe, Japan, and the USA. Treatment periods ranged from 12 weeks to three years. Overall, studies were judged to be at unclear or high risk of bias across all domains, and the quality of the evidence was poor, with GRADE rated as low or very low certainty. In low certainty evidence, ACEi (benazepril 10 mg or trandolapril 2 mg) compared to placebo may make little or no difference to death (any cause) (2 studies, 8873 participants): RR 2.00, 95% CI 0.26 to 15.37; I² = 76%), total cardiovascular events (2 studies, 8873 participants): RR 0.97, 95% CI 0.90 to 1.05; I² = 0%), cardiovascular-related death (2 studies, 8873 participants): RR 1.73, 95% CI 0.26 to 11.66; I² = 54%), stroke (2 studies, 8873 participants): RR 0.76, 95% CI 0.56 to 1.03; I² = 0%), myocardial infarction (2 studies, 8873 participants): RR 1.00, 95% CI 0.84 to 1.20; I² = 0%), and adverse events (2 studies, 8873 participants): RR 1.33, 95% CI 1.26 to 1.41; I² = 0%). It is uncertain whether ACEi (benazepril 10 mg or trandolapril 2 mg) compared to placebo reduces congestive heart failure (1 study, 8290 participants): RR 0.75, 95% CI 0.59 to 0.95) or transient ischaemic attack (1 study, 583 participants): RR 0.94, 95% CI 0.06 to 15.01; I² = 0%) because the certainty of the evidence is very low. It is uncertain whether ARB (losartan 50 mg) compared to placebo (1 study, 226 participants) reduces: death (any-cause) (no events), adverse events (RR 19.34, 95% CI 1.14 to 328.30), eGFR rate of decline (MD 5.00 mL/min/1.73 m2, 95% CI 3.03 to 6.97), presence of proteinuria (MD -0.65 g/24 hours, 95% CI -0.78 to -0.52), systolic blood pressure (MD -0.80 mm Hg, 95% CI -3.89 to 2.29), or diastolic blood pressure (MD -1.10 mm Hg, 95% CI -3.29 to 1.09) because the certainty of the evidence is very low. It is uncertain whether ACEi (enalapril 20 mg, perindopril 2 mg or trandolapril 1 mg) compared to ARB (olmesartan 20 mg, losartan 25 mg or candesartan 4 mg) (1 study, 26 participants) reduces: proteinuria (MD -0.40, 95% CI -0.60 to -0.20), systolic blood pressure (MD -3.00 mm Hg, 95% CI -6.08 to 0.08) or diastolic blood pressure (MD -1.00 mm Hg, 95% CI -3.31 to 1.31) because the certainty of the evidence is very low.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine the effectiveness of ACEi or ARB in patients with stage 1 to 3 CKD who do not have DM. The available evidence is overall of very low certainty and high risk of bias. We have identified an area of large uncertainty for a group of patients who account for most of those diagnosed as having CKD.

Incident Stroke Events in Clinical Trials of Antihypertensive Drugs in Cardiovascular Disease Patients: A Network Meta-analysis of Randomized Controlled Trials

Antihypertensive drugs are commonly used in cardiovascular diseases (CVD), less is known about the comparative effectiveness of different antihypertensive drugs on stroke events in CVD patients. We searched MEDLINE, EMBASE, the Cochrane Library, and the Web of Science for randomized controlled trails comparing the different antihypertensive drugs for stroke events in CVD patients from inception until November, 2022. Pairwise and network meta-analysis were performed to compare of different antihypertensive drugs for the incidence of stroke events in CVD patients. The protocol was registered on the PROSPERO database (CRD42022375038). 33 trials involving 141,217 CVD patients were included. The incidence of stroke in CVD patients for each antihypertensive drugs was placebo (3.0%), ACEI (2.4%), ARB (4.1%), CCB (1.8%), β blocker (1.3%), and diuretic (3.6%). Antihypertensive drug was significantly reducing stroke events in CVD patients when compared with placebo (OR 0.82; 95% CI 0.75 to 0.89). Specifically, ACEI (OR 0.82; 95% CI, 0.69-0.97), ARB (OR 0.87; 95% CI, 0.77-0.98), CCB (OR 0.69; 95% CI, 0.54-to 0.87), and diuretic (OR 0.74; 95% CI, 0.57-0.95) were significantly reducing stroke events in CVD patients when compared with placebo. Network meta-analysis suggested CCB and diuretic ranked the first and second in reducing the incidence of stroke events in CVD patients with the SUCRA value of 90.9% and 73.8%. CCB and diuretic had the greatest possibility to reduce the incidence of stroke events in CVD patients, while, ACEI was the worst antihypertensive agents in reducing the incidence of stroke events in CVD patients.

A reference-free R-learner for treatment recommendation

Assigning optimal treatments to individual patients based on their characteristics is the ultimate goal of precision medicine. Deriving evidence-based recommendations from observational data while considering the causal treatment effects and patient heterogeneity is a challenging task, especially in situations of multiple treatment options. Herein, we propose a reference-free R-learner based on a simplex algorithm for treatment recommendation. We showed through extensive simulation that the proposed method produced accurate recommendations that corresponded to optimal treatment outcomes, regardless of the reference group. We used the method to analyze data from the Systolic Blood Pressure Intervention Trial (SPRINT) and achieved recommendations consistent with the current clinical guidelines.

Benefits and risks of antihypertensive medication in adults with different systolic blood pressure: A meta-analysis from the perspective of the number needed to treat

Background

The blood pressure (BP) threshold for initial pharmacological treatment remains controversial. The number needed to treat (NNT) is a significant indicator. This study aimed to explore the benefits and risks of antihypertensive medications in participants with different systolic BPs (SBPs), and cardiovascular disease status from the perspective of the NNT.

Methods

We conducted a meta-analysis of 52 randomized placebo-controlled trials. The data were extracted from published articles and pooled to calculate NNTs. The participants were divided into five groups, based on the mean SBP at entry (120–129.9, 130–139.9, 140–159.9, 160–179.9, and ≥180 mmHg). Furthermore, we stratified patients into those with and without cardiovascular disease. The primary outcomes were the major adverse cardiovascular events (MACEs), and adverse events (AEs) leading to discontinuation.

Results

Antihypertensive medications were not associated with MACEs, however, it increased AEs, when the SBP was <140 mmHg. For participants with cardiovascular disease or at a high risk of heart failure and stroke, antihypertensive treatment reduced MACEs when SBP was ≥130 mmHg. Despite this, only 2–4 subjects had reduced MACEs per 100 patients receiving antihypertensive medications for 3.50 years. The number of individuals who needed to treat to avoid MACEs declined with an increased cardiovascular risk.

Conclusion

Pharmacological treatment could be activated when SBP reaches 140 mmHg. For people with cardiovascular disease or at a higher risk of stroke and heart failure, 130 mmHg may be a better therapeutic threshold. It could be more cost-effective to prioritize antihypertensive medications for people with a high risk of developing cardiovascular disease.

Effects of elevated systolic blood pressure on ischemic heart disease: a Burden of Proof study

High systolic blood pressure (SBP) is a major risk factor for ischemic heart disease (IHD), the leading cause of death worldwide. Using data from published observational studies and controlled trials, we estimated the mean SBP-IHD dose-response function and burden of proof risk function (BPRF), and we calculated a risk outcome score (ROS) and corresponding star rating (one to five). We found a very strong, significant harmful effect of SBP on IHD, with a mean risk-relative to that at 100 mm Hg SBP-of 1.39 (95% uncertainty interval including between-study heterogeneity 1.34-1.44) at 120 mm Hg, 1.81 (1.70-1.93) at 130 mm Hg and 4.48 (3.81-5.26) at 165 mm Hg. The conservative BPRF measure indicated that SBP exposure between 107.5 and 165.0 mm Hg raised risk by 101.36% on average, yielding a ROS of 0.70 and star rating of five. Our analysis shows that IHD risk was already increasing at 120 mm Hg SBP, rising steadily up to 165 mm Hg and increasing less steeply above that point. Our study endorses the need to prioritize and strengthen strategies for screening, to raise awareness of the need for timely diagnosis and treatment of hypertension and to increase the resources allocated for understanding primordial prevention of elevated blood pressure.

Antihypertensive treatment and risk of cancer: an individual participant data meta-analysis

BACKGROUND

Some studies have suggested a link between antihypertensive medication and cancer, but the evidence is so far inconclusive. Thus, we aimed to investigate this association in a large individual patient data meta-analysis of randomised clinical trials.

METHODS

We searched PubMed, MEDLINE, The Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov from Jan 1, 1966, to Sept 1, 2019, to identify potentially eligible randomised controlled trials. Eligible studies were randomised controlled trials comparing one blood pressure lowering drug class with a placebo, inactive control, or other blood pressure lowering drug. We also required that trials had at least 1000 participant years of follow-up in each treatment group. Trials without cancer event information were excluded. We requested individual participant data from the authors of eligible trials. We pooled individual participant-level data from eligible trials and assessed the effects of angiotensin-converting enzyme inhibitors (ACEIs), angiotensin II receptor blockers (ARBs), β blockers, calcium channel blockers, and thiazide diuretics on cancer risk in one-stage individual participant data and network meta-analyses. Cause-specific fixed-effects Cox regression models, stratified by trial, were used to calculate hazard ratios (HRs). The primary outcome was any cancer event, defined as the first occurrence of any cancer diagnosed after randomisation. This study is registered with PROSPERO (CRD42018099283).

FINDINGS

33 trials met the inclusion criteria, and included 260 447 participants with 15 012 cancer events. Median follow-up of included participants was 4·2 years (IQR 3·0-5·0). In the individual participant data meta-analysis comparing each drug class with all other comparators, no associations were identified between any antihypertensive drug class and risk of any cancer (HR 0·99 [95% CI 0·95-1·04] for ACEIs; 0·96 [0·92-1·01] for ARBs; 0·98 [0·89-1·07] for β blockers; 1·01 [0·95-1·07] for thiazides), with the exception of calcium channel blockers (1·06 [1·01-1·11]). In the network meta-analysis comparing drug classes against placebo, we found no excess cancer risk with any drug class (HR 1·00 [95% CI 0·93-1·09] for ACEIs; 0·99 [0·92-1·06] for ARBs; 0·99 [0·89-1·11] for β blockers; 1·04 [0·96-1·13] for calcium channel blockers; 1·00 [0·90-1·10] for thiazides).

INTERPRETATION

We found no consistent evidence that antihypertensive medication use had any effect on cancer risk. Although such findings are reassuring, evidence for some comparisons was insufficient to entirely rule out excess risk, in particular for calcium channel blockers.

FUNDING

British Heart Foundation, National Institute for Health Research, Oxford Martin School.

Traditional Risk Factors are Causally Related to Carotid Intima-Media Thickness Progression: Inferences from Observational Cohort Studies and Interventional Trials

In the present review, associations between traditional vascular risk factors (VRFs) and carotid intimamedial thickness progression (C-IMTp) as well as the effects of therapies for VRFs control on C-IMTp were appraised to infer causality between each VRF and C-IMTp. Cohort studies indicate that smoking, binge drinking, fatness, diabetes, hypertension and hypercholesterolemia are associated with accelerated C-IMTp. An exception is physical activity, with mixed data. Interventions for the control of obesity, diabetes, hypertension and hypercholesterolemia decelerate C-IMTp. Conversely, scarce information is available regarding the effect of smoking cessation, stop of excessive alcohol intake and management of the metabolic syndrome. Altogether, these data support a causative role of several traditional VRFs on C-IMTp. Shortcomings in study design and/or ultrasonographic protocols may account for most negative studies, which underlines the importance of careful consideration of methodological aspects in investigations using C-IMTp as the outcome.

Angiotensin II and leukocyte trafficking: New insights for an old vascular mediator. Role of redox-signaling pathways

Inflammation and activation of the immune system are key molecular and cellular events in the pathogenesis of cardiovascular diseases, including atherosclerosis, hypertension-induced target-organ damage, and abdominal aortic aneurysm. Angiotensin II (Ang-II) is the main effector peptide hormone of the renin-angiotensin system. Beyond its role as a potent vasoconstrictor and regulator of blood pressure and fluid homeostasis, Ang-II is intimately involved in the development of vascular lesions in cardiovascular diseases through the activation of different immune cells. The migration of leukocytes from circulation to the arterial subendothelial space is a crucial immune response in lesion development that is mediated through a sequential and coordinated cascade of leukocyte-endothelial cell adhesive interactions involving an array of cell adhesion molecules present on target leukocytes and endothelial cells and the generation and release of chemoattractants that activate and guide leukocytes to sites of emigration. In this review, we outline the key events of Ang-II participation in the leukocyte recruitment cascade, the underlying mechanisms implicated, and the corresponding redox-signaling pathways. We also address the use of inhibitor drugs targeting the effects of Ang-II in the context of leukocyte infiltration in these cardiovascular pathologies, and examine the clinical data supporting the relevance of blocking Ang-II-induced vascular inflammation.

Carotid Intima-Media Thickness Progression as Surrogate Marker for Cardiovascular Risk: Meta-Analysis of 119 Clinical Trials Involving 100 667 Patients

BACKGROUND

To quantify the association between effects of interventions on carotid intima-media thickness (cIMT) progression and their effects on cardiovascular disease (CVD) risk.

METHODS

We systematically collated data from randomized, controlled trials. cIMT was assessed as the mean value at the common-carotid-artery; if unavailable, the maximum value at the common-carotid-artery or other cIMT measures were used. The primary outcome was a combined CVD end point defined as myocardial infarction, stroke, revascularization procedures, or fatal CVD. We estimated intervention effects on cIMT progression and incident CVD for each trial, before relating the 2 using a Bayesian meta-regression approach.

RESULTS

We analyzed data of 119 randomized, controlled trials involving 100 667 patients (mean age 62 years, 42% female). Over an average follow-up of 3.7 years, 12 038 patients developed the combined CVD end point. Across all interventions, each 10 μm/y reduction of cIMT progression resulted in a relative risk for CVD of 0.91 (95% Credible Interval, 0.87-0.94), with an additional relative risk for CVD of 0.92 (0.87-0.97) being achieved independent of cIMT progression. Taken together, we estimated that interventions reducing cIMT progression by 10, 20, 30, or 40 μm/y would yield relative risks of 0.84 (0.75-0.93), 0.76 (0.67-0.85), 0.69 (0.59-0.79), or 0.63 (0.52-0.74), respectively. Results were similar when grouping trials by type of intervention, time of conduct, time to ultrasound follow-up, availability of individual-participant data, primary versus secondary prevention trials, type of cIMT measurement, and proportion of female patients.

CONCLUSIONS

The extent of intervention effects on cIMT progression predicted the degree of CVD risk reduction. This provides a missing link supporting the usefulness of cIMT progression as a surrogate marker for CVD risk in clinical trials.

Benefits and harms of lower blood pressure treatment targets: systematic review and meta-analysis of randomised placebo-controlled trials

OBJECTIVES

To assess the effect of antihypertensive treatment in the 130-140 mm Hg systolic blood pressure range.

DESIGN

Systematic review and meta-analysis.

INFORMATION SOURCES

PubMed, CDSR and DARE were searched for the systematic reviews, which were manually browsed for clinical trials. PubMed and Cochrane Central Register of Controlled Trials were searched for trials directly in February 2018.

ELIGIBILITY CRITERIA

Randomised double-blind trials with ≥1000 patient-years of follow-up, comparing any antihypertensive agent against placebo.

DATA EXTRACTION AND RISK OF BIAS

Two reviewers extracted study-level data, and assessed risk of bias using Cochrane Collaborations risk of bias assessment tool, independently.

MAIN OUTCOMES AND MEASURES

Primary outcomes were all-cause mortality, major cardiovascular events and discontinuation due to adverse events. Secondary outcomes were cardiovascular mortality, myocardial infarction, stroke, heart failure, hypotension-related adverse events and renal impairment.

RESULTS

Eighteen trials, including 92 567 participants (34% women, mean age 63 years), fulfilled the inclusion criteria. Primary preventive antihypertensive treatment was associated with a neutral effect on all-cause mortality (relative risk 1.00, 95% CI 0.95 to 1.06) and major cardiovascular events (1.01, 0.96 to 1.06), but an increased risk of discontinuation due to adverse events (1.23, 1.03 to 1.47). None of the secondary efficacy outcomes were significantly reduced, but the risk of hypotension-related adverse events increased with treatment (1.71, 1.32 to 2.22). In coronary artery disease secondary prevention, antihypertensive treatment was associated with reduced risk of all-cause mortality (0.91, 0.83 to 0.99) and major cardiovascular events (0.85, 0.77 to 0.94), but doubled the risk of adverse events leading to discontinuation (2.05, 1.62 to 2.61).

CONCLUSION

Primary preventive blood pressure lowering in the 130-140 mm Hg systolic blood pressure range adds no cardiovascular benefit, but increases the risk of adverse events. In the secondary prevention, benefits should be weighed against harms.

PROSPERO REGISTRATION NUMBER

CRD42018088642.

Hydrochlorothiazide and alternative diuretics versus renin-angiotensin system inhibitors for the regression of left ventricular hypertrophy: a head-to-head meta-analysis

BACKGROUND

Found in 36-41% of hypertension, elevated left ventricular mass (LVM) independently predicts cardiovascular events and total mortality. Conversely, drug-induced regression of LVM predicts improved outcomes. Previous studies have favored renin-angiotensin system inhibitors (RASIs) over other antihypertensives for reducing LVM but ignored differences among thiazide-type diuretics. From evidence regarding potency, cardiovascular events, and electrolytes, we hypothesized a priori that 'CHIP' diuretics [CHlorthalidone, Indapamide and Potassium-sparing Diuretic/hydrochlorothiazide (PSD/HCTZ)] would rival RASIs for reducing LVM.

METHOD AND RESULTS

Systematic review yielded 12 relevant double-blind randomized trials. CHIPs were more closely associated with reduced LVM than HCTZ (P = 0.004), indicating that RASIs must be compared with each diuretic separately. Publication bias favoring RASIs was corrected by cumulative analysis. For reducing LVM, HCTZ tended to be less effective than RASIs. However, the following surpassed RASIs: chlorthalidone Hedge's G: -0.37 (95% CI -0.72 to -0.02), P = 0.036; indapamide -0.20 (-0.39 to -0.01), P = 0.035; all CHIPs combined (with 61% of patients in one trial) -0.25 (-0.41to -0.09), P = 0.002. Statistical significance (P < 0.05) did not depend on any one trial. CHIPs reduction in LVM was 37% greater than that from RASIs. CHIPs superiority tended to increase with trial duration, from a negligible effect at 0.5 year to a maximal effect at 0.9-1.0 years: -0.26 (-0.43 to -0.09), P = 0.003. Fifty-eight percent of patients had information on echocardiographic components of LVM: relative to RASIs, CHIPs significantly reduced end-diastolic LV internal dimension (EDLVID): -0.18 (-0.36 to -0.00), P = 0.046. Strength of evidence favoring CHIPs over RASIs was at least moderate.

CONCLUSION

In these novel results in patients with hypertension, CHIPs surpassed RASIs for reducing LVM and EDLVID.

Pharmacotherapy for hypertension in adults 60 years or older

BACKGROUND

This is the second substantive update of this review. It was originally published in 1998 and was previously updated in 2009. Elevated blood pressure (known as 'hypertension') increases with age - most rapidly over age 60. Systolic hypertension is more strongly associated with cardiovascular disease than is diastolic hypertension, and it occurs more commonly in older people. It is important to know the benefits and harms of antihypertensive treatment for hypertension in this age group, as well as separately for people 60 to 79 years old and people 80 years or older.

OBJECTIVES

Primary objective• To quantify the effects of antihypertensive drug treatment as compared with placebo or no treatment on all-cause mortality in people 60 years and older with mild to moderate systolic or diastolic hypertensionSecondary objectives• To quantify the effects of antihypertensive drug treatment as compared with placebo or no treatment on cardiovascular-specific morbidity and mortality in people 60 years and older with mild to moderate systolic or diastolic hypertension• To quantify the rate of withdrawal due to adverse effects of antihypertensive drug treatment as compared with placebo or no treatment in people 60 years and older with mild to moderate systolic or diastolic hypertension SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to 24 November 2017: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We contacted authors of relevant papers regarding further published and unpublished work.

SELECTION CRITERIA

Randomised controlled trials of at least one year's duration comparing antihypertensive drug therapy versus placebo or no treatment and providing morbidity and mortality data for adult patients (≥ 60 years old) with hypertension defined as blood pressure greater than 140/90 mmHg.

DATA COLLECTION AND ANALYSIS

Outcomes assessed were all-cause mortality; cardiovascular morbidity and mortality; cerebrovascular morbidity and mortality; coronary heart disease morbidity and mortality; and withdrawal due to adverse effects. We modified the definition of cardiovascular mortality and morbidity to exclude transient ischaemic attacks when possible.

MAIN RESULTS

This update includes one additional trial (MRC-TMH 1985). Sixteen trials (N = 26,795) in healthy ambulatory adults 60 years or older (mean age 73.4 years) from western industrialised countries with moderate to severe systolic and/or diastolic hypertension (average 182/95 mmHg) met the inclusion criteria. Most of these trials evaluated first-line thiazide diuretic therapy for a mean treatment duration of 3.8 years.Antihypertensive drug treatment reduced all-cause mortality (high-certainty evidence; 11% with control vs 10.0% with treatment; risk ratio (RR) 0.91, 95% confidence interval (CI) 0.85 to 0.97; cardiovascular morbidity and mortality (moderate-certainty evidence; 13.6% with control vs 9.8% with treatment; RR 0.72, 95% CI 0.68 to 0.77; cerebrovascular mortality and morbidity (moderate-certainty evidence; 5.2% with control vs 3.4% with treatment; RR 0.66, 95% CI 0.59 to 0.74; and coronary heart disease mortality and morbidity (moderate-certainty evidence; 4.8% with control vs 3.7% with treatment; RR 0.78, 95% CI 0.69 to 0.88. Withdrawals due to adverse effects were increased with treatment (low-certainty evidence; 5.4% with control vs 15.7% with treatment; RR 2.91, 95% CI 2.56 to 3.30. In the three trials restricted to persons with isolated systolic hypertension, reported benefits were similar.This comprehensive systematic review provides additional evidence that the reduction in mortality observed was due mostly to reduction in the 60- to 79-year-old patient subgroup (high-certainty evidence; RR 0.86, 95% CI 0.79 to 0.95). Although cardiovascular mortality and morbidity was significantly reduced in both subgroups 60 to 79 years old (moderate-certainty evidence; RR 0.71, 95% CI 0.65 to 0.77) and 80 years or older (moderate-certainty evidence; RR 0.75, 95% CI 0.65 to 0.87), the magnitude of absolute risk reduction was probably higher among 60- to 79-year-old patients (3.8% vs 2.9%). The reduction in cardiovascular mortality and morbidity was primarily due to a reduction in cerebrovascular mortality and morbidity.

AUTHORS' CONCLUSIONS

Treating healthy adults 60 years or older with moderate to severe systolic and/or diastolic hypertension with antihypertensive drug therapy reduced all-cause mortality, cardiovascular mortality and morbidity, cerebrovascular mortality and morbidity, and coronary heart disease mortality and morbidity. Most evidence of benefit pertains to a primary prevention population using a thiazide as first-line treatment.

Effects of lowering diastolic blood pressure to <80 mmHg on cardiovascular mortality and events in patients with coronary artery disease: a systematic review and meta-analysis

The target of diastolic blood pressure (DBP) remains controversial in patients with coronary artery disease (CAD). We systematically searched PubMed/Medline and the Cochrane Central database for randomized controlled trials (RCTs) assessing the efficacy and safety of reducing DBP in CAD patients from January 1965 to July 2017. Seven placebo-controlled RCTs enrolling 34,814 CAD patients who achieved DBP <80 mmHg were included in the drug-intervention group. The average achieved blood pressures (BPs) were 126.3/75.1 and 131.5/77.8 mmHg in the drug-intervention and placebo-control groups, respectively. Drug intervention was associated with an 11% reduction in coronary revascularization and a 31% reduction in heart failure. In the drug-intervention group, all-cause death, myocardial infarction, angina pectoris, and stroke were reduced with marginal significance, whereas hypotension was increased by 123%. A meta-analysis of four RCTs, in which the achieved DBP was <75 mmHg, showed that the drug intervention was associated with a 22% reduction in heart failure. These results suggest that reducing DBP to 80 mmHg or less would significantly reduce coronary revascularization and heart failure but at the expense of causing hypotension in CAD patients. Further trials are warranted to prove this issue.

First-line drugs for hypertension

BACKGROUND

This is the first update of a review published in 2009. Sustained moderate to severe elevations in resting blood pressure leads to a critically important clinical question: What class of drug to use first-line? This review attempted to answer that question.

OBJECTIVES

To quantify the mortality and morbidity effects from different first-line antihypertensive drug classes: thiazides (low-dose and high-dose), beta-blockers, calcium channel blockers, ACE inhibitors, angiotensin II receptor blockers (ARB), and alpha-blockers, compared to placebo or no treatment.Secondary objectives: when different antihypertensive drug classes are used as the first-line drug, to quantify the blood pressure lowering effect and the rate of withdrawal due to adverse drug effects, compared to placebo or no treatment.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to November 2017: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1946), Embase (from 1974), the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov. We contacted authors of relevant papers regarding further published and unpublished work.

SELECTION CRITERIA

Randomized trials (RCT) of at least one year duration, comparing one of six major drug classes with a placebo or no treatment, in adult patients with blood pressure over 140/90 mmHg at baseline. The majority (over 70%) of the patients in the treatment group were taking the drug class of interest after one year. We included trials with both hypertensive and normotensive patients in this review if the majority (over 70%) of patients had elevated blood pressure, or the trial separately reported outcome data on patients with elevated blood pressure.

DATA COLLECTION AND ANALYSIS

The outcomes assessed were mortality, stroke, coronary heart disease (CHD), total cardiovascular events (CVS), decrease in systolic and diastolic blood pressure, and withdrawals due to adverse drug effects. We used a fixed-effect model to to combine dichotomous outcomes across trials and calculate risk ratio (RR) with 95% confidence interval (CI). We presented blood pressure data as mean difference (MD) with 99% CI.

MAIN RESULTS

The 2017 updated search failed to identify any new trials. The original review identified 24 trials with 28 active treatment arms, including 58,040 patients. We found no RCTs for ARBs or alpha-blockers. These results are mostly applicable to adult patients with moderate to severe primary hypertension. The mean age of participants was 56 years, and mean duration of follow-up was three to five years.High-quality evidence showed that first-line low-dose thiazides reduced mortality (11.0% with control versus 9.8% with treatment; RR 0.89, 95% CI 0.82 to 0.97); total CVS (12.9% with control versus 9.0% with treatment; RR 0.70, 95% CI 0.64 to 0.76), stroke (6.2% with control versus 4.2% with treatment; RR 0.68, 95% CI 0.60 to 0.77), and coronary heart disease (3.9% with control versus 2.8% with treatment; RR 0.72, 95% CI 0.61 to 0.84).Low- to moderate-quality evidence showed that first-line high-dose thiazides reduced stroke (1.9% with control versus 0.9% with treatment; RR 0.47, 95% CI 0.37 to 0.61) and total CVS (5.1% with control versus 3.7% with treatment; RR 0.72, 95% CI 0.63 to 0.82), but did not reduce mortality (3.1% with control versus 2.8% with treatment; RR 0.90, 95% CI 0.76 to 1.05), or coronary heart disease (2.7% with control versus 2.7% with treatment; RR 1.01, 95% CI 0.85 to 1.20).Low- to moderate-quality evidence showed that first-line beta-blockers did not reduce mortality (6.2% with control versus 6.0% with treatment; RR 0.96, 95% CI 0.86 to 1.07) or coronary heart disease (4.4% with control versus 3.9% with treatment; RR 0.90, 95% CI 0.78 to 1.03), but reduced stroke (3.4% with control versus 2.8% with treatment; RR 0.83, 95% CI 0.72 to 0.97) and total CVS (7.6% with control versus 6.8% with treatment; RR 0.89, 95% CI 0.81 to 0.98).Low- to moderate-quality evidence showed that first-line ACE inhibitors reduced mortality (13.6% with control versus 11.3% with treatment; RR 0.83, 95% CI 0.72 to 0.95), stroke (6.0% with control versus 3.9% with treatment; RR 0.65, 95% CI 0.52 to 0.82), coronary heart disease (13.5% with control versus 11.0% with treatment; RR 0.81, 95% CI 0.70 to 0.94), and total CVS (20.1% with control versus 15.3% with treatment; RR 0.76, 95% CI 0.67 to 0.85).Low-quality evidence showed that first-line calcium channel blockers reduced stroke (3.4% with control versus 1.9% with treatment; RR 0.58, 95% CI 0.41 to 0.84) and total CVS (8.0% with control versus 5.7% with treatment; RR 0.71, 95% CI 0.57 to 0.87), but not coronary heart disease (3.1% with control versus 2.4% with treatment; RR 0.77, 95% CI 0.55 to 1.09), or mortality (6.0% with control versus 5.1% with treatment; RR 0.86, 95% CI 0.68 to 1.09).There was low-quality evidence that withdrawals due to adverse effects were increased with first-line low-dose thiazides (5.0% with control versus 11.3% with treatment; RR 2.38, 95% CI 2.06 to 2.75), high-dose thiazides (2.2% with control versus 9.8% with treatment; RR 4.48, 95% CI 3.83 to 5.24), and beta-blockers (3.1% with control versus 14.4% with treatment; RR 4.59, 95% CI 4.11 to 5.13). No data for these outcomes were available for first-line ACE inhibitors or calcium channel blockers. The blood pressure data were not used to assess the effect of the different classes of drugs as the data were heterogeneous, and the number of drugs used in the trials differed.

AUTHORS' CONCLUSIONS

First-line low-dose thiazides reduced all morbidity and mortality outcomes in adult patients with moderate to severe primary hypertension. First-line ACE inhibitors and calcium channel blockers may be similarly effective, but the evidence was of lower quality. First-line high-dose thiazides and first-line beta-blockers were inferior to first-line low-dose thiazides.

Blood pressure-lowering treatment strategies based on cardiovascular risk versus blood pressure: A meta-analysis of individual participant data

BACKGROUND

Clinical practice guidelines have traditionally recommended blood pressure treatment based primarily on blood pressure thresholds. In contrast, using predicted cardiovascular risk has been advocated as a more effective strategy to guide treatment decisions for cardiovascular disease (CVD) prevention. We aimed to compare outcomes from a blood pressure-lowering treatment strategy based on predicted cardiovascular risk with one based on systolic blood pressure (SBP) level.

METHODS AND FINDINGS

We used individual participant data from the Blood Pressure Lowering Treatment Trialists' Collaboration (BPLTTC) from 1995 to 2013. Trials randomly assigned participants to either blood pressure-lowering drugs versus placebo or more intensive versus less intensive blood pressure-lowering regimens. We estimated 5-y risk of CVD events using a multivariable Weibull model previously developed in this dataset. We compared the two strategies at specific SBP thresholds and across the spectrum of risk and blood pressure levels studied in BPLTTC trials. The primary outcome was number of CVD events avoided per persons treated. We included data from 11 trials (47,872 participants). During a median of 4.0 y of follow-up, 3,566 participants (7.5%) experienced a major cardiovascular event. Areas under the curve comparing the two treatment strategies throughout the range of possible thresholds for CVD risk and SBP demonstrated that, on average, a greater number of CVD events would be avoided for a given number of persons treated with the CVD risk strategy compared with the SBP strategy (area under the curve 0.71 [95% confidence interval (CI) 0.70-0.72] for the CVD risk strategy versus 0.54 [95% CI 0.53-0.55] for the SBP strategy). Compared with treating everyone with SBP ≥ 150 mmHg, a CVD risk strategy would require treatment of 29% (95% CI 26%-31%) fewer persons to prevent the same number of events or would prevent 16% (95% CI 14%-18%) more events for the same number of persons treated. Compared with treating everyone with SBP ≥ 140 mmHg, a CVD risk strategy would require treatment of 3.8% (95% CI 12.5% fewer to 7.2% more) fewer persons to prevent the same number of events or would prevent 3.1% (95% CI 1.5%-5.0%) more events for the same number of persons treated, although the former estimate was not statistically significant. In subgroup analyses, the CVD risk strategy did not appear to be more beneficial than the SBP strategy in patients with diabetes mellitus or established CVD.

CONCLUSIONS

A blood pressure-lowering treatment strategy based on predicted cardiovascular risk is more effective than one based on blood pressure levels alone across a range of thresholds. These results support using cardiovascular risk assessment to guide blood pressure treatment decision-making in moderate- to high-risk individuals, particularly for primary prevention.

Association of Blood Pressure Lowering With Mortality and Cardiovascular Disease Across Blood Pressure Levels: A Systematic Review and Meta-analysis

IMPORTANCE

High blood pressure (BP) is the most important risk factor for death and cardiovascular disease (CVD) worldwide. The optimal cutoff for treatment of high BP is debated.

OBJECTIVE

To assess the association between BP lowering treatment and death and CVD at different BP levels.

DATA SOURCES

Previous systematic reviews were identified from PubMed, the Cochrane Database of Systematic Reviews, and the Database of Abstracts of Reviews of Effect. Reference lists of these reviews were searched for randomized clinical trials. Randomized clinical trials published after November 1, 2015, were also searched for in PubMed and the Cochrane Central Register for Controlled Trials during February 2017.

STUDY SELECTION

Randomized clinical trials with at least 1000 patient-years of follow-up, comparing BP-lowering drugs vs placebo or different BP goals were included.

DATA EXTRACTION AND SYNTHESIS

Data were extracted from original publications. Risk of bias was assessed using the Cochrane Collaborations assessment tool. Relative risks (RRs) were pooled in random-effects meta-analyses with Knapp-Hartung modification. Results are reported according to PRISMA guidelines.

MAIN OUTCOMES AND MEASURES

Prespecified outcomes of interest were all-cause mortality, cardiovascular mortality, major cardiovascular events, coronary heart disease (CHD), stroke, heart failure, and end-stage renal disease.

RESULTS

Seventy-four unique trials, representing 306 273 unique participants (39.9% women and 60.1% men; mean age, 63.6 years) and 1.2 million person-years, were included in the meta-analyses. In primary prevention, the association of BP-lowering treatment with major cardiovascular events was dependent on baseline systolic BP (SBP). In trials with baseline SBP 160 mm Hg or above, treatment was associated with reduced risk for death (RR, 0.93; 95% CI, 0.87-1.00) and a substantial reduction of major cardiovascular events (RR, 0.78; 95% CI, 0.70-0.87). If baseline SBP ranged from 140 to 159 mm Hg, the association of treatment with mortality was similar (RR, 0.87; 95% CI, 0.75-1.00), but the association with major cardiovascular events was less pronounced (RR, 0.88; 95% CI, 0.80-0.96). In trials with baseline SBP below 140 mm Hg, treatment was not associated with mortality (RR, 0.98; 95% CI, 0.90-1.06) and major cardiovascular events (RR, 0.97; 95% CI, 0.90-1.04). In trials including people with previous CHD and mean baseline SBP of 138 mm Hg, treatment was associated with reduced risk for major cardiovascular events (RR, 0.90; 95% CI, 0.84-0.97), but was not associated with survival (RR, 0.98; 95% CI, 0.89-1.07).

CONCLUSIONS AND RELEVANCE

Primary preventive BP lowering is associated with reduced risk for death and CVD if baseline SBP is 140 mm Hg or higher. At lower BP levels, treatment is not associated with any benefit in primary prevention but might offer additional protection in patients with CHD.

Angiotensin-converting enzyme inhibitors reduce mortality compared to angiotensin receptor blockers: Systematic review and meta-analysis

Background There are few reviews comparing the long-term outcomes of the use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers in a hypertensive population because both are effective in reducing blood pressure. None of them compared angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers with a placebo group in patients with essential hypertension, because few studies exist with this design. Methods A systematic search of PUBMED, LILACS, SCIELO, ICTRP, Cochrane, EMBASE and ClinicalTrials.gov from 1 January 2000 until 31 December 2015 selected prospective studies that reported an association between the use of angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers in the following cardiovascular outcomes: heart failure/hospitalisation, stroke, acute myocardial infarction, total cardiovascular deaths, total deaths and total outcomes. Summary odds ratios (ORs) and 95% confidence intervals (CIs) were combined by using a fixed-effects model. Results Seventeen studies ( n = 73,761) were included of which 12 studies were randomly assigned to angiotensin II receptor blocker therapy ( n = 24,697) and five to angiotensin-converting enzyme inhibitors ( n = 12,170). Angiotensin-converting enzyme inhibitors proved to be significant in reducing total deaths (OR 0.85, 95% CI 0.78-0.93) and cardiovascular deaths (OR 0.77, 95% CI 0.69-0.87). Angiotensin II receptor blocker therapy did not show a reduction in total deaths (OR 1.02, 95% CI 0.96-1.09) or cardiovascular deaths (OR 0.95, 95% CI 0.86-1.06). For acute myocardial infarction, stroke and heart failure/hospitalisation, the reductions were significant for both classes. Conclusion Angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker use is similar in preventing major cardiovascular outcomes regarding acute myocardial infarction, stroke and heart failure/hospitalisation. However, the use of angiotensin-converting enzyme inhibitors is more effective in reducing total deaths and cardiovascular deaths than angiotensin II receptor blockers.

Angiotensin-Converting Enzyme Inhibitors and Angiotensin II Receptor Blockers Are Associated With Improved Outcome but Do Not Prevent New-Onset Atrial Fibrillation After Acute Myocardial Infarction

BACKGROUND

Treatment with renin-angiotensin system (RAS) inhibitors might restrain the structural/electrical remodeling associated with atrial fibrillation (AF). Limited evidence exists regarding the potential benefits of RAS inhibition post-acute myocardial infarction (AMI) in patients with AF. This study sought to assess the association between RAS inhibition and all-cause mortality and new-onset AF in patients with/without congestive heart failure (CHF) post-AMI.

METHODS AND RESULTS

Patients hospitalized for AMI between 2006 and 2012 were identified in Swedish registries. Patients were stratified in 4 subgroups; patients with CHF and AF (n=11 489); patients with CHF without AF (n=31 676); patients with AF without CHF (n=10 066); and patients without both CHF and AF (n=59 417). Patients exposed to RAS inhibition were compared to nontreated. Three-year risk of all-cause mortality and new-onset AF was assessed using adjusted Cox regression analyses. At discharge, 83 291 (73.9%) patients received RAS inhibition. RAS inhibition was associated with lower 3-year risk of all-cause mortality in CHF patients with AF, adjusted hazard ratio (HR) with 95% CI 0.75 (0.70-0.81), CHF patients without AF, HR 0.65 (0.60-0.69), AF patients without CHF, HR 0.82 (0.75-0.90), and in patients without CHF and AF, HR 0.76 (0.72-0.81), respectively. RAS inhibition was not associated with lower 3-year risk of new-onset AF in patients without AF but with/without CHF; HR 0.96 (0.84-1.10) and 1.12 (1.02-1.22), respectively.

CONCLUSIONS

RAS inhibition post-AMI was associated with lower risk of all-cause mortality. In patients with/without CHF, RAS inhibition was not associated with lower incidence of new-onset AF.

Carotid Intima-media Thickness Measurements: Relations with Atherosclerosis, Risk of Cardiovascular Disease and Application in Randomized Controlled Trials

Advances in the field of carotid ultrasound have been incremental, resulting in a steady decrease in measurement variability. Improvements in edge detection algorithms point toward increasing automation of CIMT measurements. The major advantage of CIMT is that it is completely noninvasive and can be repeated as often as required. It provides a continuous measure since all subjects have a measurable carotid wall. It is also relatively inexpensive to perform, and the technology is widely available. A graded relation between raising LDL cholesterol and increased CIMT is apparent. Increased CIMT has been shown consistently to relate the atherosclerotic abnormalities elsewhere in the arterial system. Moreover, increased CIMT predicts future vascular events in both populations from Caucasian ancestry and those from Asian ancestry. Furthermore, lipid‑lowering therapy has been shown to affect CIMT progression within 12–18 months in properly designed trials with results congruent with clinical events trials. In conclusion, when one wants to evaluate the effect of a pharmaceutical intervention that is to be expected to beneficially affect atherosclerosis progression and to reduce CV event risk, the use of CIMT measurements over time is a valid, suitable, and evidence‑based choice.

The potential role of angiotensin-converting enzyme inhibition in peripheral arterial disease

Peripheral arterial disease (PAD) is associated with significant morbidity and mortality, and yet remains under-recognized and under-treated. Atherosclerosis is the most common cause of lower extremity PAD and pharmacological interventions that alter this central pathogenic role of atherosclerosis may alter the natural history of PAD. There is growing evidence that the renin-angiotensin system (RAS) is a significant mediator of this disease process and that treatment with angiotensin-converting enzyme (ACE) inhibitors is associated with vasculoprotective effects that are independent of the antihypertensive properties of these agents. Numerous lines of evidence suggest that ACE inhibitors directly inhibit the atherosclerotic process and improve vascular endothelial function. In patients with PAD, ACE inhibitors have been shown to improve peripheral circulation as measured by peripheral arterial blood pressure and by increases in peripheral blood flow. Preliminary evidence suggests that ACE inhibitors might improve clinical symptoms in patients with PAD. Recent evidence has confirmed that ACE inhibition is associated with a decrease in morbidity and mortality in patients with arterial disease without left ventricular dysfunction; this benefit was at least as great for the subset of patients with PAD. Overall, these data support a significant role for the RAS in the pathogenesis of all atherosclerotic diseases (including PAD) and suggest that the benefit is independent of the blood pressure lowering properties of these agents. These studies suggest that ACE inhibitor therapy should be considered in the routine management of individuals with PAD, regardless of whether they have hypertension or left ventricular dysfunction.

Tissue ACE Inhibitors for Secondary Prevention of Cardiovascular Disease in Patients With Preserved Left Ventricular Function: A Pooled Meta-analysis of Randomized Placebo-controlled Trials

Objective. A pooled meta-analysis of published, randomized placebo-controlled clinical trials to evaluate the role of tissue angiotensin-converting enzyme (ACE) inhibitors in secondary prevention of cardiovascular disease in patients with preserved left ventricular function. Sources. Peer-reviewed journals listed in Index Medicus/MEDLINE, the Cochrane Central Register of Controlled Clinical Trials, and the Cochrane Database of Systematic Reviews. Study selection . Randomized placebo-controlled clinical trials of at least 12 months' duration, in patients with a prior cardiovascular event or at high risk for cardiovascular events, were analyzed. Data synthesis and analysis. A total of 31 555 patients (136 882 patient-years) from 4 trials were selected for the meta-analysis. Relative risk estimations were made using data pooled from these trials, and statistical significance was determined using the χ2 test. The number of patients needed to treat was also calculated for each outcome. Results. Tissue ACE inhibitors significantly reduced the risk of all-cause mortality, cardiovascular mortality, acute myocardial infarction, and stroke ( P < .001 for each). The need for invasive coronary revascularization was reduced ( P = .03), as was the risk of hospitalization for congestive heart failure ( P = .001). The occurrence of new-onset diabetes was also significantly reduced ( P < .001), but the risk of hospitalization for angina was not significantly affected ( P = .677). Treating about 100 patients for about 4.5 years would prevent 1 death, 1 non-fatal myocardial infarction, 1 cardiovascular death, or 1 invasive coronary revascularization. Conclusions. Tissue ACE inhibitors have demonstrated benefit when used for secondary prevention of cardiovascular disease in patients with preserved left ventricular function in randomized placebo-controlled clinical trials.

Triamterene Enhances the Blood Pressure Lowering Effect of Hydrochlorothiazide in Patients with Hypertension

BACKGROUND

Triamterene, because of its potassium-sparing properties, is frequently used in combination with hydrochlorothiazide (HCTZ) to treat patients with hypertension. By inhibiting the epithelial sodium channel (ENaC) in the cortical collecting duct, triamterene reduces potassium secretion, thus reducing the risk of hypokalemia. Whether triamterene has an independent effect on blood pressure (BP) has not been well studied.

OBJECTIVE

To determine if triamterene provides an effect to further lower BP in patients treated with HCTZ.

DESIGN

We conducted an observational study using electronic medical record data from the Indiana Network for Patient Care. Participants were 17,291 patients with the diagnosis of hypertension between 2004 and 2012.

MAIN MEASURES

BP was the primary outcome. We compared the BP between patients who were taking HCTZ, with and without triamterene, either alone or in combination with other antihypertensive medications, by using a propensity score analysis. For each medication combination, we estimated the propensity score (i.e., probability) of a patient receiving triamterene using a logistic regression model. Patients with similar propensity scores were stratified into subclasses and BP was compared between those taking triamterene or not within each subclass; the effect of triamterene was then assessed by combining BP differences estimated from all subclasses.

KEY RESULTS

The mean systolic BP in the triamterene + HCTZ group was 3.8 mmHg lower than in the HCTZ only group (p < 0.0001); systolic BP was similarly lower for patients taking triamterene with other medication combinations. Systolic BP reduction was consistently observed for different medication combinations. The range of systolic BP reduction was between 1 and 4 mm Hg, depending on the concurrently used medications.

CONCLUSIONS

In the present study, triamterene was found to enhance the effect of HCTZ to lower BP. In addition to its potassium-sparing action, triamterene's ability to lower BP should also be considered.

Effects of blood pressure reduction in mild hypertension: a systematic review and meta-analysis

BACKGROUND

Effects of blood pressure reduction in persons with grade 1 hypertension are unclear.

PURPOSE

To investigate whether pharmacologic blood pressure reduction prevents cardiovascular events and deaths in persons with grade 1 hypertension.

DATA SOURCES

Trials included in the BPLTTC (Blood Pressure Lowering Treatment Trialists' Collaboration) and trials identified from a previous review and electronic database searches.

STUDY SELECTION

Patients without cardiovascular disease with blood pressures in the grade 1 hypertension range (140 to 159/90 to 99 mm Hg) who were randomly assigned to an active (antihypertensive drug or more intensive regimen) or control (placebo or less intensive regimen) blood pressure-lowering regimen.

DATA EXTRACTION

Individual-patient data from BPLTTC trials and aggregate data from other trials were extracted. Risk of bias was assessed for all trials.

DATA SYNTHESIS

Individual-patient data involved 10 comparisons from trials where most patients had diabetes, and aggregate data involved 3 comparisons from trials of patients without diabetes. The average blood pressure reduction was about 3.6/2.4 mm Hg. Over 5 years, odds ratios were 0.86 (95% CI, 0.74 to 1.01) for total cardiovascular events, 0.72 (CI, 0.55 to 0.94) for strokes, 0.91 (CI, 0.74 to 1.12) for coronary events, 0.80 (CI, 0.57 to 1.12) for heart failure, 0.75 (CI, 0.57 to 0.98) for cardiovascular deaths, and 0.78 (CI, 0.67 to 0.92) for total deaths. Results were similar in secondary analyses. Withdrawal from treatment due to adverse effects was more common in the active groups.

LIMITATION

Blood pressure reductions and numbers of events were small.

CONCLUSION

Blood pressure-lowering therapy is likely to prevent stroke and death in patients with uncomplicated grade 1 hypertension.

PRIMARY FUNDING SOURCE

Swedish Heart-Lung Foundation, Swedish Research Council, Australian Research Council, and National Health and Medical Research Council of Australia.

Blood pressure-lowering treatment based on cardiovascular risk: a meta-analysis of individual patient data

BACKGROUND

We aimed to investigate whether the benefits of blood pressure-lowering drugs are proportional to baseline cardiovascular risk, to establish whether absolute risk could be used to inform treatment decisions for blood pressure-lowering therapy, as is recommended for lipid-lowering therapy.

METHODS

This meta-analysis included individual participant data from trials that randomly assigned patients to either blood pressure-lowering drugs or placebo, or to more intensive or less intensive blood pressure-lowering regimens. The primary outcome was total major cardiovascular events, consisting of stroke, heart attack, heart failure, or cardiovascular death. Participants were separated into four categories of baseline 5-year major cardiovascular risk using a risk prediction equation developed from the placebo groups of the included trials (<11%, 11-15%, 15-21%, >21%).

FINDINGS

11 trials and 26 randomised groups met the inclusion criteria, and included 67,475 individuals, of whom 51,917 had available data for the calculation of the risk equations. 4167 (8%) had a cardiovascular event during a median of 4·0 years (IQR 3·4-4·4) of follow-up. The mean estimated baseline levels of 5-year cardiovascular risk for each of the four risk groups were 6·0% (SD 2·0), 12·1% (1·5), 17·7% (1·7), and 26·8% (5·4). In each consecutive higher risk group, blood pressure-lowering treatment reduced the risk of cardiovascular events relatively by 18% (95% CI 7-27), 15% (4-25), 13% (2-22), and 15% (5-24), respectively (p=0·30 for trend). However, in absolute terms, treating 1000 patients in each group with blood pressure-lowering treatment for 5 years would prevent 14 (95% CI 8-21), 20 (8-31), 24 (8-40), and 38 (16-61) cardiovascular events, respectively (p=0·04 for trend).

INTERPRETATION

Lowering blood pressure provides similar relative protection at all levels of baseline cardiovascular risk, but progressively greater absolute risk reductions as baseline risk increases. These results support the use of predicted baseline cardiovascular disease risk equations to inform blood pressure-lowering treatment decisions.

FUNDING

None.

Primary and secondary prevention of stroke by antihypertensive drug treatment

Hypertension is the most powerful risk factor for stroke. Antihypertensive drug treatment reduces the incidence of stroke. In a meta-analysis of actively controlled trials, calcium-channel blockers, including (-8%; p = 0.07) or excluding verapamil (-10%; p = 0.02), as well as angiotensin Type 1 receptor blockers (-24%; p = 0.0002) resulted in better stroke prevention than the old drugs (diuretics or beta-blockers), whereas the opposite trend was observed for angiotensin-converting enzyme inhibitors (+10%; p = 0.03). An overview of six trials conducted in patients with a history of cerebrovascular disease demonstrated that blood pressure-lowering therapy reduced stroke recurrence by 25% (p = 0.004). A meta-regression analysis showed that within-trial differences in systolic blood pressure accounted for the prevention of stroke in most trials. This finding was corroborated by the recently published Valsartan Antihypertensive Long-term Use Evaluation trial.

Blood pressure lowering and major cardiovascular events in people with and without chronic kidney disease: meta-analysis of randomised controlled trials

OBJECTIVE

To define the cardiovascular effects of lowering blood pressure in people with chronic kidney disease.

DESIGN

Collaborative prospective meta-analysis of randomised trials.

DATA SOURCES AND ELIGIBILITY

Participating randomised trials of drugs to lower blood pressure compared with placebo or each other or that compare different blood pressure targets, with at least 1000 patient years of follow-up per arm.

MAIN OUTCOME MEASURES

Major cardiovascular events (stroke, myocardial infarction, heart failure, or cardiovascular death) in composite and individually and all cause death.

PARTICIPANTS

26 trials (152,290 participants), including 30,295 individuals with reduced estimated glomerular filtration rate (eGFR), which was defined as eGFR <60 mL/min/1.73 m(2).

DATA EXTRACTION

Individual participant data were available for 23 trials, with summary data from another three. Meta-analysis according to baseline kidney function was performed. Pooled hazard ratios per 5 mm Hg lower blood pressure were estimated with a random effects model.

RESULTS

Compared with placebo, blood pressure lowering regimens reduced the risk of major cardiovascular events by about a sixth per 5 mm Hg reduction in systolic blood pressure in individuals with (hazard ratio 0.83, 95% confidence interval 0.76 to 0.90) and without reduced eGFR (0.83, 0.79 to 0.88), with no evidence for any difference in effect (P=1.00 for homogeneity). The results were similar irrespective of whether blood pressure was reduced by regimens based on angiotensin converting enzyme inhibitors, calcium antagonists, or diuretics/β blockers. There was no evidence that the effects of different drug classes on major cardiovascular events varied between patients with different eGFR (all P>0.60 for homogeneity).

CONCLUSIONS

Blood pressure lowering is an effective strategy for preventing cardiovascular events among people with moderately reduced eGFR. There is little evidence from these overviews to support the preferential choice of particular drug classes for the prevention of cardiovascular events in chronic kidney disease.

Carotid artery intima-media thickness and the renin-angiotensin system

Carotid artery intima-media thickness (IMT) is a biomarker for cardiovascular disease that also predicts the risk of cardiovascular mortality. Angiotensin-converting enzyme (ACE) inhibition is a unique therapeutic modality because it both treats hypertension and improves arterial health and cardiovascular disease outcomes. Controversy exists regarding the role of ACE inhibitors and angiotensin receptor blockers (ARBs) in IMT regression. Our article provides an update on how ACE inhibitors and ARBs could play a role in decreasing IMT.

A meta-analysis reporting effects of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in patients without heart failure

OBJECTIVES

The goal of the study was to assess the effects of angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin receptor blockers (ARBs) on the composite of cardiovascular (CV) death, myocardial infarction (MI), and stroke, and on all-cause death, new-onset heart failure (HF), and new-onset diabetes mellitus (DM) in high-risk patients without HF.

BACKGROUND

ACE-Is reduce CV events in high-risk patients without HF whereas the effects of ARBs are less certain.

METHODS

Twenty-six randomized trials comparing ARBs or ACE-Is versus placebo in 108,212 patients without HF were collected in a meta-analysis and analyzed for the risk of the composite outcome, all-cause death, new-onset HF, and new-onset DM.

RESULTS

ACE-Is significantly reduced the risk of the composite outcome (odds ratio [OR]: 0.830 [95% confidence interval (CI): 0.744 to 0.927]; p = 0.001), MI (OR: 0.811 [95% CI: 0.748 to 0.879]; p < 0.001), stroke (OR: 0.796 [95% CI: 0.682 to 0.928]; p < 0.004), all-cause death (OR: 0.908 [95% CI: 0.845 to 0.975]; p = 0.008), new-onset HF (OR: 0.789 [95% CI: 0.686 to 0.908]; p = 0.001), and new-onset DM (OR: 0.851 [95% CI: 0.749 to 0.965]; p < 0.012). ARBs significantly reduced the risk of the composite outcome (OR: 0.920 [95% CI: 0.869 to 0.975], p = 0.005), stroke (OR: 0.900 [95% CI: 0.830 to 0.977], p = 0.011), and new-onset DM (OR: 0.855 [95% CI: 0.798 to 0.915]; p < 0.001).

CONCLUSIONS

In patients at high CV risk without HF, ACE-Is and ARBs reduced the risk of the composite outcome of CV death, MI, and stroke. ACE-Is also reduced the risk of all-cause death, new-onset HF, and new-onset DM. Thus, ARBs represent a valuable option to reduce CV mortality and morbidity in patients in whom ACE-Is cannot be used.

Long-term treatment with sulfhydryl angiotensin-converting enzyme inhibition reduces carotid intima-media thickening and improves the nitric oxide/oxidative stress pathways in newly diagnosed patients with mild to moderate primary hypertension

Aim. Sulfhydryl angiotensin-converting enzyme (ACE) inhibitors exert antiatherosclerotic effects in preclinical models and antioxidant effects in patients. However, whether ACE inhibitors have any clinically significant antiatherogenic effects remains still debated. Objectives. In mildly hypertensive patients, we evaluated the effect of the sulfhydryl ACE inhibitor zofenopril in comparison with the carboxylic ACE inhibitor enalapril on carotid atherosclerosis (intima-media thickness [IMT] and vascular lumen diameter) and systemic oxidative stress (nitrite/nitrate, asymmetrical dimethyl-L-arginine, and isoprostanes). Material and methods. In 2001, we started a small prospective randomized clinical trial on 48 newly diagnosed mildly hypertensive patients with no additional risk factors for atherosclerosis (eg, hyperlipidemia, smoke habit, familiar history of atherosclerosisrelated diseases or diabetes). Patients were randomly assigned either to the enalapril (20 mg/d, n = 24) or the zofenopril group (30 mg/d, n = 24); the planned duration of the trial was 5 years. Carotid IMT and vascular lumen diameter were determined by ultrasonography for all patients at baseline and at 1, 3, and 5 years. Furthermore, nitrite/nitrate, asymmetrical dimethyl-L-arginine, and isoprostane levels were measured. Results. In our conditions, IMT of the right and left common carotid arteries was similar at baseline in both groups (P = NS). Intima-media thickness measurements until 5 years revealed a significant reduction in the zofenopril group but not in the enalapril group (P b .05 vs enalapril-treated group). This effect was coupled with a favorable nitric oxide/oxidative stress profile in the zofenopril group. Conclusion. Long-term treatment with the sulfhydryl ACE inhibitor zofenopril besides its blood pressure–lowering effects may slow the progression of IMT of the carotid artery in newly diagnosed mildly hypertensive patients. (Am Heart J 2008;156:1154.e1-1154.e8.)

Effect of a pharmacist-managed hypertension program on health system costs: an evaluation of the Study of Cardiovascular Risk Intervention by Pharmacists-Hypertension (SCRIP-HTN)

STUDY OBJECTIVE

To quantify the potential cost savings of a community pharmacy-based hypertension management program based on the results of the Study of Cardiovascular Risk Intervention by Pharmacists-Hypertension (SCRIP-HTN) study in terms of avoided cardiovascular events-myocardial infarction, stroke, and heart failure hospitalization, and to compare these cost savings with the cost of the pharmacist intervention program.

DESIGN

An economic model was developed to estimate the potential cost avoidance in direct health care resources from reduced cardiovascular events over a 1-year period.

MEASUREMENTS AND MAIN RESULTS

The SCRIP-HTN study found that patients with diabetes mellitus and hypertension who were receiving the pharmacist intervention had a greater mean reduction in systolic blood pressure of 5.6 mm Hg than patients receiving usual care. For our model, published meta-analysis data were used to compute cardiovascular event absolute risk reductions associated with a 5.6-mm Hg reduction in systolic blood pressure over 6 months. Costs/event were obtained from administrative data, and probabilistic sensitivity analyses were performed to assess the robustness of the results. Two program scenarios were evaluated-one with monthly follow-up for a total of 1 year with sustained blood pressure reduction, and the other in which pharmacist care ended after the 6-month program but the effects on systolic blood pressure diminished over time. The cost saving results from the economic model were then compared with the costs of the program. Annual estimated cost savings (in 2011 Canadian dollars) from avoided cardiovascular events were $265/patient (95% confidence interval [CI] $63-467) if the program lasted 1 year or $221/patient (95%CI $72-371) if pharmacist care ceased after 6 months with an assumed loss of effect afterward. Estimated pharmacist costs were $90/patient for 6 months or $150/patient for 1 year, suggesting that pharmacist-managed programs are cost saving, with the annual net total cost savings/patient estimated to be $131 for a program lasting 6 months or $115 for a program lasting 1 year.

CONCLUSION

Our model found that community pharmacist interventions capable of reducing systolic blood pressure by 5.6 mm Hg within 6 months are cost saving and result in improved patient outcomes. Wider adoption of pharmacist-managed hypertension care for patients with diabetes and hypertension is encouraged.

The role of renin angiotensin system intervention in stage B heart failure

This article outlines the link between the renin angiotensin aldosterone system (RAAS) and various forms of cardiomyopathy, and also reviews the understanding of the effectiveness of RAAS intervention in this phase of ventricular dysfunction. The authors focus their discussion predominantly on patients who have had previous myocardial infarction or those who have left ventricular hypertrophy and also briefly discuss the role of RAAS activation and intervention in patients with alcoholic cardiomyopathy.

Safety and efficacy of the sulfydryl ACE-inhibitor zofenopril in the management of cardiovascular disease

In the 1970s, pharmacological therapy interrupting the renin-angiotensin system was considered beneficial for patients with high-renin hypertension. Angiotensin-converting enzyme (ACE) inhibitors proved to be effective not only in patients with high renin and elevated blood pressure, but also in many hypertensive patients with normal levels of plasma renin activity. ACE inhibitors are used in a wide range of chronic illnesses such as atherosclerosis, hypertension, myocardial infarction, heart failure, diabetic complications, and stroke. To date, more than ninety controlled clinical trials evaluating the beneficial effects of 14 different ACE inhibitors were conducted. Moreover, data from experimental studies showed that ACE inhibitors can attenuate the development of atherosclerosis, oxidative stress, and vascular inflammation in a wide range of species indicating that ACE inhibition also favourably affects the vasculature. More than fifteen years ago, the bi-sulfydryl ACE-inhibitor zofenopril has shown an excellent clinical safety and efficacy in patients with hypertension and in those with myocardial infarction. More recently, this compound exhibited a potent antioxidant and antiatherosclerotic effect indicating a clinical useful vasoprotective action.

Mortality and morbidity during and after the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

A randomized, double-blind, active-controlled, multicenter trial assigned 32,804 participants aged 55 years and older with hypertension and ≥ 1 other coronary heart disease risk factors to receive chlorthalidone (n=15,002), amlodipine (n=8898), or lisinopril (n=8904) for 4 to 8 years, when double-blinded therapy was discontinued. Passive surveillance continued for a total follow-up of 8 to 13 years using national administrative databases to ascertain deaths and hospitalizations. During the post-trial period, fatal outcomes and nonfatal outcomes were available for 98% and 65% of participants, respectively, due to lack of access to administrative databases for the remainder. This paper assesses whether mortality and morbidity differences persisted or new differences developed during the extended follow-up. Primary outcome was cardiovascular mortality and secondary outcomes were mortality, stroke, coronary heart disease, heart failure, cardiovascular disease, and end-stage renal disease. For the post-trial period, data are not available on medications or blood pressure levels. No significant differences (P<.05) appeared in cardiovascular mortality for amlodipine (hazard ratio [HR], 1.00; 95% confidence interval [CI], 0.93-1.06) or lisinopril (HR, 0.97; CI, 0.90-1.03), each compared with chlorthalidone. The only significant differences in secondary outcomes were for heart failure, which was higher with amlodipine (HR, 1.12; CI, 1.02-1.22), and stroke mortality, which was higher with lisinopril (HR, 1.20; CI, 1.01-1.41), each compared with chlorthalidone. Similar to the previously reported in-trial result, there was a significant treatment-by-race interaction for cardiovascular disease for lisinopril vs chlorthalidone. Black participants had higher risk than non-black participants taking lisinopril compared with chlorthalidone. After accounting for multiple comparisons, none of these results were significant. These findings suggest that neither calcium channel blockers nor angiotensin-converting enzyme inhibitors are superior to diuretics for the long-term prevention of major cardiovascular complications of hypertension.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for adults with early (stage 1 to 3) non-diabetic chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is a long term condition that occurs as a result of damage to the kidneys. Early recognition of CKD is becoming increasingly common due to widespread laboratory estimated glomerular filtration rate (eGFR) reporting, raised clinical awareness, and international adoption of Kidney Disease Outcomes Quality Initiative (K/DOQI) classification. Early recognition and management of CKD affords the opportunity not only to prepare for progressive kidney impairment and impending renal replacement therapy, but also for intervening to reduce the risk of progression and cardiovascular disease. Angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) are two classes of antihypertensive drugs that act on the renin-angiotensin-aldosterone system. Beneficial effects of ACEi and ARB on renal outcomes and survival in people with a wide range of severity of renal impairment have been reported; however, their effectiveness in the subgroup of people with early CKD (stage 1 to 3) is less certain.

OBJECTIVES

This review aimed to evaluate the benefits and harms of ACEi and ARB or both in the management of people with early (stage 1 to 3) CKD who do not have diabetes mellitus.

SEARCH STRATEGY

In March 2010 we searched The Cochrane Library, including The Cochrane Renal Group's specialised register and The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Reference lists of review articles and relevant studies were also checked. The search was conducted using the optimally sensitive strategy developed by the Cochrane Collaboration for the identification of randomised controlled trials (RCTs) with input from an expert in trial search strategy.

SELECTION CRITERIA

All RCTs reporting the effect of ACEi or ARB in people with early (stage 1 to 3) CKD who did not have diabetes mellitus were selected for inclusion. Only studies of at least four weeks duration were selected. Authors, working in teams of two, independently assessed the retrieved titles and abstracts, and whenever necessary the full text of these studies were screened to determine which studies satisfied the inclusion criteria.

DATA COLLECTION AND ANALYSIS

Data extraction was carried out by two authors, independently, using a standard data extraction form and cross checked by two other authors. Methodological quality of included studies was assessed using the Cochrane risk of bias tool. Data entry was carried out by one author and cross checked by another author. When more than one study reported similar outcomes, data were pooled using the random-effects model, but a fixed-effect model was also analysed to ensure the robustness of the model chosen and to check susceptibility to outliers. Heterogeneity was analysed using a Chi² test on N-1 degrees of freedom, with an alpha of 0.05 used for statistical significance and with the I² test. Where data permitted, subgroup analysis was used to explore possible sources of heterogeneity. The quality of the evidence was analysed.

MAIN RESULTS

Four RCTs enrolling 2177 participants met our inclusion criteria. Of these, three compared ACEi with placebo and one compared ACEi with ARB. Two studies had an overall low risk of bias, and the other two were considered to be at moderate to high risk of bias. Low to moderate quality of evidence (from two studies representing 1906 patients) suggested that ACEi had no impact on all-cause mortality (RR 1.80, 95% CI 0.17 to 19.27, P = 0.63) or cardiovascular events (RR 0.87, 95% CI 0.66 to 1.14, P = 0.31) in people with stage 3 CKD. For all-cause mortality, there was substantial heterogeneity in the results. One study (quality assessment: low risk of bias) reported no difference in the risk of end-stage kidney disease in those with an eGFR > 45 mL/min/1.74 m² treated with ACEi versus placebo (RR 1.00, 95% CI 0.09 to 1.11, P = 0.99). The (high risk of bias) study that compared ACEi with ARB reported little difference in effect between the treatments when urinary protein, blood pressure or creatinine clearance were compared. No published studies comparing ARB with placebo or ACEi and ARB with placebo were identified.

AUTHORS' CONCLUSIONS

Our review demonstrated that there is currently insufficient evidence to determine the effectiveness of ACEi or ARB in patients with stage 1 to 3 CKD who do not have diabetes mellitus. We have identified an area of significant uncertainty for a group of patients who account for most of those labelled as having CKD.

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.

Does achieving an intensive versus usual blood pressure level prevent stroke?

OBJECTIVE

The purpose of this study was to compare the impact of achieving tight versus usual systolic blood pressure (SBP) control on stroke prevention through meta-analysis of randomized controlled trials.

METHODS

We searched PubMed and bibliographies of recent review articles. Relative risk with 95% confidence interval was used as a measure of the association between an active treatment group with achieved SBP <130 mmHg versus a comparator group with achieved SBP 130 to 139 mmHg, and risk of stroke after pooling data across trials.

RESULTS

The search identified 11 studies with 42,572 participants and 794 stroke events. The final SBPs, weighted for trial size, were a mean of 126.5 mmHg in the intensive treatment arms and 132.6 mmHg in the conventional arms (mean SBP reduction, 6.1 mmHg). Achieving a tight SBP level was associated with a lower stroke risk (relative risk, 0.80; 95% confidence interval, 0.70-0.92; p < 0.01) and a lower risk of major vascular events (0.91; 0.86-0.96; p < 0.001). In subgroup analyses, subjects with risk factors but no established cardiovascular disease showed substantial reduction of future stroke risk with tight control (0.49; 0.34-0.69), but those with established cardiovascular disease at entry did not experience stroke risk reduction with tight control (0.92; 0.83-1.03).

INTERPRETATION

Achieving an SBP <130 mmHg compared to 130 to 139 mmHg appears to provide additional stroke protection only among people with risk factors but no established cardiovascular disease.

The effects of blood pressure reduction and of different blood pressure-lowering regimens on major cardiovascular events according to baseline blood pressure: meta-analysis of randomized trials

BACKGROUND

The benefits of reducing blood pressure are well established, but there remains uncertainty about whether the magnitude of the effect varies with the initial blood pressure level. The objective was to compare the risk reductions achieved by different blood pressure-lowering regimens among individuals with different baseline blood pressures.

METHODS

Thirty-two randomized controlled trials were included and seven comparisons between different types of treatments were made. For each comparison, the primary prespecified analysis included calculation of summary estimates of effect using random-effects meta-analysis for major cardiovascular events in four groups defined by baseline SBP (<140, 140-159, 160-179, and ≥ 180 mmHg).

RESULTS

There were 201 566 participants among whom 20 079 primary outcome events were observed. There was no evidence of differences in the proportionate risk reductions achieved with different blood pressure-lowering regimens across groups defined according to higher or lower levels of baseline SBP (all P for trend > 0.17). This finding was broadly consistent for comparisons of different regimens, for DBP categories, and for commonly used blood pressure cut-points.

CONCLUSION

It appears unlikely that the effectiveness of blood pressure-lowering treatments depends substantively upon starting blood pressure level. As the majority of patients in the trials contributing to these overviews had a history of hypertension or were receiving background blood pressure-lowering therapy, the findings suggest that additional blood pressure reduction in hypertensive patients meeting initial blood pressure targets will produce further benefits. More broadly, the data are supportive of the utilization of blood pressure-lowering regimens in high-risk patients with and without hypertension.

Imagine how many lives you save: angiotensin-converting enzyme inhibition for atherosclerotic vascular disease in the present era of risk reduction

INTRODUCTION

Angiotensin-converting enzyme (ACE) inhibition is clearly beneficial in patients with hypertension, heart failure, and post-myocardial infarction left ventricular (LV) dysfunction. However, whereas initial trials had reported a benefit of ACE inhibition in high-risk vascular patients, current trials of ACE inhibition have failed to demonstrate a clear benefit in vascular patients who are receiving risk-reduction interventions. The purpose of this review is to analyze the reasons behind the failure of the most recent trials of ACE inhibitors in vascular patients without overt LV dysfunction. The reader will gain an understanding of the time-dependent trend towards a reduction in the absolute benefit conferred by ACE inhibition in patients with vascular atherosclerosis as risk reduction interventions are increasingly implemented.

AREAS COVERED

Major trials with a follow-up period of at least 1 year assessing the use of ACE inhibitors in patients with a history of cardiac or vascular events were identified via a PubMed literature search. All-cause and cardiovascular mortality outcomes were reported for each trial, as well as the use of aspirin, lipid-lowering drugs and β-blockers, and the mean LV ejection fraction.

EXPERT OPINION

The findings of recent trials do not support the use of ACE inhibitors in vascular patients who, adherent with risk reduction therapy, do not have hypertension, diabetes, or LV dysfunction.