Valsartan in a Japanese population with hypertension and other cardiovascular disease (Jikei Heart Study): a randomised, open-label, blinded endpoint morbidity-mortality study

Temporary treatment with AT1 receptor blocker, valsartan, from early stage of hypertension prevented vascular remodeling

BACKGROUND

The present study examined the inhibitory action of temporary treatment with an angiotensin type 1 (AT(1)) receptor blocker (ARB) on vascular remodeling using hypertensive mice with overexpression of the human renin (hRN) and angiotensinogen (hANG) genes.

METHODS

hRN/hANG transgenic mice (hRN/hANG-Tg) were treated with an ARB, valsartan, from 4 weeks of age. In some mice, valsartan treatment was stopped at 8 weeks of age (temporary treatment). Inflammatory vascular injury was induced by polyethylene-cuff placement around the femoral artery at the age of 10 weeks.

RESULTS

Compared with wild-type (WT) mice, hRN/hANG-Tg showed higher blood pressure (BP) and enhancement of oxidative stress and medial thickening even before cuff placement. Inflammatory vascular remodeling and oxidative stress after cuff placement were further enhanced in hRN/hANG-Tg. Temporary treatment with valsartan continuously lowered BP even after cessation of administration, and inhibited these changes. In contrast, administration of hydralazine lowered BP to a similar level to that with valsartan, but did not inhibit medial thickening and inflammatory vascular remodeling. In contrast to the valsartan treatment, BP immediately increased to the untreated level after cessation of hydralazine.

CONCLUSIONS

These results indicate that temporary ARB treatment leads to prolonged effect of BP lowering and prevents vascular remodeling in hypertensive mice induced by activation of the human renin-angiotensin system. The inhibitory action of valsartan is not due to the BP lowering but is at least in part due to a decrease in oxidative stress and inflammation.

Angiotensin receptor blockers and risk of myocardial infarction: meta-analyses and trial sequential analyses of 147 020 patients from randomised trials

OBJECTIVES

To evaluate the cardiovascular outcomes and other outcomes associated with angiotensin receptor blockers.

DESIGN

Systematic review of randomised controlled trials with meta-analysis and trial sequential analysis (TSA).

DATA SOURCES AND STUDY SELECTION

Pubmed, Embase, and CENTRAL searches for randomised clinical trials, until August 2010, of angiotensin receptor blockers compared with controls (placebo/active treatment) that enrolled at least 100 participants and had a follow-up of at least one year.

DATA EXTRACTION

Myocardial infarction, death, cardiovascular death, angina pectoris, stroke, heart failure, and new onset diabetes.

RESULTS

37 randomised clinical trials included 147,020 participants and had a total follow-up of 485,166 patient years. When compared with controls (placebo/active treatment), placebo, or active treatment, angiotensin receptor blockers were not associated with an increase in the risk of myocardial infarction (relative risk 0.99, 95% confidence interval 0.92 to 1.07), death, cardiovascular death, or angina pectoris. Compared with controls, angiotensin receptor blockers were associated with a reduction in the risk of stroke (0.90, 0.84 to 0.98), heart failure (0.87, 0.81 to 0.93), and new onset diabetes (0.85, 0.78 to 0.93), with similar results when compared with placebo or with active treatment. Based on trial sequential analysis, there is no evidence even for an average 5.0-7.5% (upper confidence interval 5-11%) relative increase in myocardial infarction (absolute increase of 0.3%), death, or cardiovascular death with firm evidence for relative risk reduction of stroke (at least 1%, average 10%) (compared with placebo only), heart failure (at least 5%, average 10%), and new onset diabetes (at least 4%, average 10%) with angiotensin receptor blockers compared with controls.

CONCLUSIONS

This large and comprehensive analysis produced firm evidence to refute the hypothesis that angiotensin receptor blockers increase the risk of myocardial infarction (ruling out even a 0.3% absolute increase). Compared with controls, angiotensin receptor blockers reduce the risk of stroke, heart failure, and new onset diabetes.

Valsartan-amlodipine-hydrochlorothiazide: the definitive fixed combination?

A significant proportion of patients with hypertension will need three or more antihypertensive agents to achieve blood pressure goals, particularly those at higher risk. On the other hand, fixed combinations provide an extra beneficial effect, as they improve medication adherence and, secondarily, the attainment of blood pressure goals during follow-up. Triple therapy is recommended in the treatment of hypertension in those patients not adequately controlled with two antihypertensive drugs. In this context, guidelines recommend the combination of a renin-angiotensin system inhibitor, a calcium channel blocker and a diuretic. The triple fixed combination of valsartan-amlodipine-hydrochlorothiazide has been shown to be an effective and safe therapy for treating hypertension and seems a logical approach for those patients uncontrolled with two antihypertensive agents as well as in those patients already treated with three drugs to improve treatment compliance. In this article, available evidence about the efficacy and tolerability of the triple fixed combined therapy valsartan-amlodipine-hydrochlorothiazide for the treatment of hypertension is updated.

Lower levels of high-density lipoprotein cholesterol on admission and a recurrence of ischemic stroke: a 12-month follow-up of the Fukuoka Stroke Registry

BACKGROUND

Despite recent progress in treatments for secondary prevention, ischemic stroke recurs in 8% to 12% of stroke survivors. We investigated the predisposing factors associated with recurrence within the first 12 months after an ischemic event to explore more effective preventive strategies.

METHODS

Between June 2007 and April 2008, acute (within 7 days of onset) ischemic stroke patients were registered in the Fukuoka Stroke Registry (FSR), a multicenter, prospective, observational database. The clinical characteristics on admission were analyzed, and the patients were followed for 12 months.

RESULTS

Two hundred sixty patients (151 males and 109 females, 71 ± 11 years of age) were registered; 25 (9.6%) had recurrence of ischemic stroke during the follow-up period. Kaplan-Meier curve analysis revealed a significant difference in recurrence-free survival between patients with high-density lipoprotein (HDL) cholesterol <40 mg/dL on admission and those with HDL cholesterol ≥ 40 mg/dL (P = .042). Adjusted multivariate logistic regression analysis showed that age (odds ratio 1.06; 95% CI, 1.00-1.11; P = .035) and HDL cholesterol <40 mg/dL (odds ratio 2.73; 95% CI, 1.01-7.38; P = .048) on admission were independently associated with a recurrence of ischemic stroke within 12 months of the initial onset.

CONCLUSIONS

Aging and low HDL cholesterol levels are considered independent risk factors for a recurrence of ischemic stroke.

Clinical Interaction between Brain and Kidney in Small Vessel Disease

Patients with chronic kidney disease (CKD) are well known to have a higher prevalence of cardiovascular disease from epidemiological studies. Recently, CKD has also been shown to be related to neurological disorders, not only ischemic brain injury but also cognitive impairment. This cerebrorenal connection is considered to involve small vessel disease in both the kidney and brain, based on their hemodynamic similarities. Clinical studies suggest that markers for CKD such as estimated glomerular filtration rate (eGFR), proteinuria, and albuminuria may be helpful to predict brain small vessel disease, white matter lesions (WMLs), silent brain ischemia (SBI), and microhemorrhages. Recently, changes in the vascular system of the brain have been shown to contribute to the onset and progression of cognitive impairment, not only vascular dementia but also Alzheimer's disease. Patients with CKD are also reported to have higher risk of impaired cognitive function in the future compared with non-CKD subjects. These results indicate that CKD markers may be helpful to predict the future risk of neuronal disease.

Moderate versus intensive treatment of hypertension with amlodipine/valsartan for patients uncontrolled on angiotensin receptor blocker monotherapy

OBJECTIVES

Many angiotensin receptor blocker (ARB) monotherapy patients need at least two agents to control blood pressure (BP). We investigated whether initiating intensive treatment with combination amlodipine/valsartan was superior to moderate treatment with amlodipine/valsartan in patients previously uncontrolled on ARB monotherapy.

METHODS

In this 12-week study, patients aged at least 18 years on ARB (other than valsartan) for at least 28 days (with treatment-naïve patients or those not controlled on agents other than an ARB treated with open-label olmesartan 20 or 40 mg, respectively, for 28 days) and with uncontrolled mean sitting systolic blood pressure (MSSBP; ≥ 150-<200 mmHg) were randomized to amlodipine/valsartan 5/320 mg (n = 369) or 5/160 mg (n = 359). At week 2, the dose was increased to 10/320 mg in the intensive arm. Hydrochlorothiazide 12.5 mg was added to both arms at week 4. Optional up-titration with hydrochlorothiazide 12.5 mg at week 8 was allowed if MSSBP was more than 140 mmHg.

RESULTS

At baseline, mean office sitting BP was comparable in the intensive (163.9/95.5 mmHg) and moderate (163.3/95.0 mmHg) groups. Intensive treatment provided greater BP reductions versus moderate treatment (P < 0.05) from week 4 (-23.0/-10.4 versus -19.2/-8.7 mmHg; primary endpoint) to week 12 (-29.0/-14.8 versus -25.3/-12.3 mmHg). Adverse events were reported by a similar percentage of patients in both groups (36.3% intensive, 37.6% moderate); peripheral edema was more common with intensive versus moderate treatment (8.7 versus 4.5%; P = 0.025).

CONCLUSIONS

Initiating treatment with an intensive dose of amlodipine/valsartan provides significantly greater BP lowering versus moderate treatment in hypertensive patients unresponsive to ARB monotherapy. Both treatment regimens were generally well tolerated based on adverse event reports, but the lack of routine laboratory testing after screening limits conclusions on tolerability.

Angiotensin II type 1 receptor blockers improve insulin sensitivity in patients with schizophrenia being treated with olanzapine

RATIONALE

Olanzapine (OLZ) is known to cause weight gain and metabolic disturbances, which may have serious implications with respect to medical comorbidities such as metabolic syndrome and insulin resistance.

OBJECTIVES

The aim of this study was to evaluate the effects of two angiotensin II type 1 receptor blockers (ARBs) which are widely used as antihypertensive agents, valsartan (VAL) and telmisartan (TEL), on insulin resistance in patients with schizophrenia treated with OLZ.

METHODS

Thirty inpatients with schizophrenia with OLZ monotherapy over 8 weeks participated in this study. To assess insulin resistance, the homeostasis model assessment of insulin resistance (HOMA-IR), fasting plasma glucose (PG) levels and immunoreactive insulin (IRI) levels were measured [HOMA-IR = fasting PG level (mmol/L) x fasting IRI level (μU/ml)/22.5]. VAL add-on treatment was performed in insulin-resistant patients (HOMA-IR > 1.6) for 12 weeks. After a 12-week VAL washout period, TEL add-on treatment was carried out for 12 weeks. The effects of ARBs on insulin resistance and other metabolic variables were assessed.

RESULTS

In all 30 patients, both body mass index and abdominal circumference were strongly correlated with HOMA-IR. Twelve patients showed high HOMA-IR and were deemed to be insulin resistant. Add-on therapy of VAL and TEL resulted in a significant decrease in fasting IRI levels and HOMA-IR. No differences in any effects were observed between VAL and TEL. No adverse effects of either ARBs were observed in this study.

CONCLUSIONS

ARBs for patients treated with OLZ improved insulin sensitivity and attenuated insulin resistance.

Usefulness of a large automated health records database in pharmacoepidemiology

OBJECTIVES

In the present study, using a large automated health records database, we investigated the incidence of cardio-cerebrovascular events, diabetes new-onset events, and dialysis initiation events in hypertensive patients, and examined the effects of antihypertensive medications on these incidences.

MATERIALS AND METHODS

We conducted a search of an automated health records database that contained anonymous information from the health insurance claims and the results of laboratory tests at 15 medical facilities across Japan. The study cohort was defined as patients who were diagnosed with hypertension and who visited a medical institution in the registration period. Events were defined by diagnosis, medication history, and laboratory test results.

RESULTS

We obtained a cohort of 20,686 patients diagnosed with hypertension. The mean (standard deviation, SD) age in the cohort was 67.9 (13.2) years, and the follow-up period was 2.56 (1.42) years. The total incidence rates per 1,000 person-years in the present study population showed good agreement with rates in reported cohort studies: 8.10 (5.6-11.1) for cerebrovascular events, 1.27 (0.5-7.4) for cerebral hemorrhage, 6.57 (4.6-8.9) for cerebral infarction, 0.46 (0.1-1.0) for subarachnoid hemorrhage, and 1.75 (1.6-4.4) for myocardial infarction. The standardized incidence rates of cardio-cerebrovascular events, diabetes new-onset events, and dialysis initiation events were 9.73, 20.94, and 5.99 events/1,000 person-years, respectively.

CONCLUSIONS

In terms of the incidence of the investigated events in hypertensive patients, the study results suggested that the automated health records database data were as valid and reliable as data from other epidemiological studies.

Evaluation of dosing time-related anti-hypertensive efficacy of valsartan in patients with type 2 diabetes

The aim of this study was to evaluate which administration timing of valsartan provides satisfactory blood pressure (BP) control, once daily in the morning, once daily in the evening, or twice daily in total 160 mg. Hypertensive patients with mild-to-moderate diabetic nephropathy were enrolled, but those with more than three anti-hypertensive agents, renal insufficiency (serum creatinine ≥ 3 mg/ dL), or hepatic insufficiency were excluded. They were randomized to receive valsartan 160mg once daily in the morning, valsartan 160 mg once daily in the evening, or valsartan 80 mg twice daily for 12 weeks according to a three-period crossover design. Office blood pressure (OBP), home blood pressure (HBP) self-measured by patients, and urinary albumin excretion adjusted by creatinine excretion (UAE) were measured every 12 weeks. In 34 patients, (male: 18, mean age: 57.5 ± 10.3), valsartan with ether all administration timing demonstrated significant reductions in OBP and HBP compared to baseline: valsartan 160 mg once daily in the morning: −12.2/−9.5 mmHg (p < 0.01); valsartan 160 mg once daily in the evening: −14.2/−10.3 mmHg (p < 0.01); valsartan 80 mg twice daily: −15.0/−10.2 mmHg (p < 0.01) There was no statistically significant differences in a decrease in OBP and HBP, and reduction of UAE among three administration timing. In conclusion, these data indicate that the efficacy on BP-lowering does not depend on administration timing of valsartan in patients with diabetic nephropathy.

Treating high blood pressure: is reaching the target more important than the means? No, the means are important

All major antihypertensive drug classes i.e. diuretics, beta-blockers, calcium antagonists and blockers of the renin-angiotensin system have been shown to effectively lower blood pressure and hence to reduce cardiovascular outcomes in hypertensive patients. These drugs decrease cardiovascular complications in hypertension essentially because they reduce systemic blood pressure. Nevertheless, there is growing evidence that the extent of the benefits differed between drug classes suggesting that the various classes of antihypertensive agents are not equivalent in their ability to protect against target organ damages and cardiovascular and renal endpoints. More recently, evidence has also accumulated to demonstrate that even combination therapies are not equally effective in reducing the occurrence of cardiovascular complications in hypertension. These recent observations suggest that the means to lower blood pressure are as important as the achieved target blood pressure in the management of hypertensive patients.

Antihypertensive drugs and risk of cancer: network meta-analyses and trial sequential analyses of 324,168 participants from randomised trials

BACKGROUND

The risk of cancer from antihypertensive drugs has been much debated, with a recent analysis showing increased risk with angiotensin-receptor blockers (ARBs). We assessed the association between antihypertensive drugs and cancer risk in a comprehensive analysis of data from randomised clinical trials.

METHODS

We undertook traditional direct comparison meta-analyses, multiple comparisons (network) meta-analyses, and trial sequential analyses. We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials from 1950, to August, 2010, for randomised clinical trials of antihypertensive therapy (ARBs, angiotensin-converting-enzyme inhibitors [ACEi], β blockers, calcium-channel blockers [CCBs], or diuretics) with follow-up of at least 1 year. Our primary outcomes were cancer and cancer-related deaths.

FINDINGS

We identified 70 randomised controlled trials (148 comparator groups) with 324,168 participants. In the network meta-analysis (fixed-effect model), we recorded no difference in the risk of cancer with ARBs (proportion with cancer 2·04%; odds ratio 1·01, 95% CI 0·93-1·09), ACEi (2·03%; 1·00, 0·92-1·09), β blockers (1·97%; 0·97, 0·88-1·07), CCBs (2·11%; 1·05, 0·96-1·13), diuretics (2·02%; 1·00, 0·90-1·11), or other controls (1·95%, 0·97, 0·74-1·24) versus placebo (2·02%). There was an increased risk with the combination of ACEi plus ARBs (2·30%, 1·14, 1·02-1·28); however, this risk was not apparent in the random-effects model (odds ratio 1·15, 95% CI 0·92-1·38). No differences were detected in cancer-related mortality for ARBs (death rate 1·33%; odds ratio 1·00, 95% CI 0·87-1·15), ACEi (1·25%; 0·95, 0·81-1·10), β blockers (1·23%; 0·93, 0·80-1·08), CCBs (1·27%; 0·96, 0·82-1·11), diuretics (1·30%; 0·98, 0·84-1·13), other controls (1·43%; 1·08, 0·78-1·46), and ACEi plus ARBs (1·45%; 1·10, 0·90-1·32). In direct comparison meta-analyses, similar results were recorded for all antihypertensive classes, except for an increased risk of cancer with ACEi and ARB combination (OR 1·14, 95% CI 1·04-1·24; p=0·004) and with CCBs (1·06, 1·01-1·12; p=0·02). However, we noted no significant differences in cancer-related mortality. On the basis of trial sequential analysis, our results suggest no evidence of even a 5-10% relative risk (RR) increase of cancer and cancer-related deaths with any individual class of antihypertensive drugs studied. However, for the ACEi and ARB combination, the cumulative Z curve crossed the trial sequential monitoring boundary, suggesting firm evidence for at least a 10% RR increase in cancer risk.

INTERPRETATION

Our analysis refutes a 5·0-10·0% relative increase in the risk of cancer or cancer-related death with the use of ARBs, ACEi, β blockers, diuretics, and CCBs. However, increased risk of cancer with the combination of ACEi and ARBs cannot be ruled out.

Candesartan and amlodipine combination therapy provides powerful vascular protection in stroke-prone spontaneously hypertensive rats

The vascular protective effects of placebo, candesartan (1 mg kg(-1) per day) monotherapy, candesartan (1 mg kg(-1) per day) and amlodipine (1 mg kg(-1) per day) combination therapy, and candesartan (1 mg kg(-1) per day) and hydrochlorothiazide (HCTZ) (10 mg kg(-1) per day) combination therapy for 2 weeks were compared in stroke-prone, spontaneously hypertensive rats. Candesartan monotherapy significantly reduced blood pressure, and both combination therapies were equally and significantly lower than the monotherapy. Acetylcholine-induced vascular relaxation was significantly stronger in all therapeutic groups than in the placebo-treated group. Furthermore, the relaxation was significantly stronger in the candesartan plus amlodipine-treated group than in the candesartan-treated group; however, there was no significant difference between the candesartan- and candesartan plus HCTZ-treated groups. Vascular gene expressions of the NADPH oxidase subunits p22(phox), gp91(phox), NOX1 and NOX4 were significantly attenuated in all therapeutic groups compared with the placebo-treated group, and there were no significant differences among those groups. However, a significant augmentation of vascular superoxide dismutase activity was observed in the candesartan plus amlodipine-treated group, but not in other groups. Malondialdehyde levels in the vascular tissues were significantly attenuated in all therapeutic groups. Compared with the candesartan-treated group, significant attenuation was observed in the candesartan plus amlodipine-treated group, but not in the candesartan plus HCTZ-treated group. Immunohistological analysis showed that areas positive for 4-hydroxy-2-nonenal were significantly reduced in all therapeutic groups, but this reduction was significantly greater for the candesartan plus amlodipine-treated group than for the candesartan-treated group. Thus, candesartan and amlodipine combination therapy could have a powerful protective effect in vascular tissues via the reduction of oxidative stress.

Renin-angiotensin system blockade in older adults with chronic kidney disease: a review of the literature

PURPOSE OF REVIEW

We have reviewed the literature examining the benefits and harms of renin-angiotensin system (RAS) blockade in older adults, using studies which included patients with chronic kidney disease (CKD) as well as those which included a broader patient population.

RECENT FINDINGS

We review the results of key trials which evaluate the impact of RAS blockade on renal outcomes, and those which address the impact of RAS blockade on more global outcomes (cardiovascular events and mortality). Many trials examining renal outcomes of RAS blockade excluded older patients or did not present age-stratified results, whereas trials which examined global outcomes often excluded patients with CKD. Most older patients with CKD have nonproteinuric nondiabetic CKD, thus differing from participants in trials which examined renal outcomes, which often included only patients with diabetes or proteinuria. Most studies did not address alternate outcomes which may carry greatest import for older patients, such as worsening comorbid illness or changes in functional status.

SUMMARY

The role of RAS inhibition for older patients with CKD remains unclear. Information on age-specific effects of RAS blockade on a range of different outcomes among older patients with CKD would improve our ability to assess the benefits and harms of RAS inhibition in this population.

Benefits of prestroke use of angiotensin type 1 receptor blockers on ischemic stroke severity

BACKGROUND

There is a general agreement that the stroke prevention benefit of antihypertensive agents is mainly based on their blood pressure lowering properties. The aim of this retrospective study was to assess the benefits of angiotensin type 1 receptor blockers (ARBs) used before the onset of ischemic stroke.

METHODS

Data were obtained between April 2007 and March 2009 using the discharge statistics of the neurologic service at Juntendo hospital. We retrieved the demographic and clinical characteristics of stroke patients and functional status upon discharge assessed by the modified Rankin Scale (mRS) and Barthel index (BI).

RESULTS

We enrolled 151 patients. Patients treated with ARBs were less often treated with a calcium channel blocker (CaB)/angiotensin-converting enzyme inhibitor (ACEI). They often had diabetes and showed better outcomes than the non-ARB group. Logistic regression analysis indicated that in patients with a mRS score of 0 to 2, older age (P < .007) was associated with severe outcomes, while the factor of pretreatment with ARB (P < .014) was associated with better outcomes. For patients with BI scores of more than 75, older age (P < .015) and large artery atherosclerosis (P < .035) were associated with severe outcomes. Logistic regression analysis identified the factor of pretreatment with ARB (P < .020) to be associated with better outcomes.

CONCLUSIONS

ARB is widely used in patients with hypertension and cardiovascular disease, and our results further support this indication.

Angiotensin II receptor blockade with valsartan decreases plasma osteopontin levels in patients with essential hypertension

Osteopontin (OPN) has recently emerged as a key factor in both vascular remodelling and development of atherosclerosis. It has been reported that OPN is regulated by the renin-angiotensin-aldosterone system (RAAS). The aim of this study was to clarify the effect of angiotensin II receptor blockade with valsartan on plasma OPN levels in patients with essential hypertension (EHT). Forty-six patients (mean age, 64±11 years) with EHT were randomly assigned to treatment with amlodipine or valsartan. There were no significant differences in baseline clinical characteristics between the two groups. Blood sampling and blood pressure evaluation were performed before and after 24 weeks of treatment. After 24 weeks, both systolic blood pressure (SBP) and diastolic blood pressure (DBP) were decreased significantly and by the same degree in each treatment group. However, valsartan but not amlodipine decreased plasma OPN levels (baseline and 24-week data-valsartan: 614±224 ng ml(-1), 472±268 ng ml(-1), P=0.006; amlodipine: 680±151 ng ml(-1), 687±234 ng ml(-1), P>0.999). A positive correlation between the reduction in OPN and the log natural (ln) C-reactive protein (CRP) was seen in the valsartan-treated group. Stepwise regression analysis showed that treatment with valsartan and the reduction of ln CRP were associated with the reduction in OPN levels, and this association was independent of the reduction in SBP or aldosterone levels (valsartan: β=0.332, P=0.026; ln CRP reduction: β=0.366, P=0.015). These results suggest that suppression of the RAAS and inflammation may decrease plasma OPN levels.

Angiotensin-receptor blockade and risk of cancer: meta-analysis of randomised controlled trials

BACKGROUND

Angiotensin-receptor blockers (ARBs) are a widely used drug class approved for treatment of hypertension, heart failure, diabetic nephropathy, and, recently, for cardiovascular risk reduction. Experimental studies implicate the renin-angiotensin system, particularly angiotensin II type-1 and type-2 receptors, in the regulation of cell proliferation, angiogenesis, and tumour progression. We assessed whether ARBs affect cancer occurrence with a meta-analysis of randomised controlled trials of these drugs.

METHODS

We searched Medline, Scopus (including Embase), Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and the US Food and Drug Administration website for studies published before November, 2009, that included any of the seven currently available ARBs. Randomised controlled trials with an ARB given in at least one group, with a follow-up of at least 1 year, and that enrolled at least 100 patients were included. New-cancer data were available for 61,590 patients from five trials. Data on common types of solid organ cancers were available for 68,402 patients from five trials, and data on cancer deaths were available for 93,515 patients from eight trials.

FINDINGS

Telmisartan was the study drug in 30,014 (85.7%) patients who received ARBs as part of the trials with new cancer data. Patients randomly assigned to receive ARBs had a significantly increased risk of new cancer occurrence compared with patients in control groups (7.2%vs 6.0%, risk ratio [RR] 1.08, 95% CI 1.01-1.15; p=0.016). When analysis was limited to trials where cancer was a prespecified endpoint, the RR was 1.11 (95% CI 1.04-1.18, p=0.001). Among specific solid organ cancers examined, only new lung-cancer occurrence was significantly higher in patients randomly assigned to receive ARBs than in those assigned to receive control (0.9%vs 0.7%, RR 1.25, 1.05-1.49; p=0.01). No statistically significant difference in cancer deaths was observed (1.8%vs 1.6%, RR 1.07, 0.97-1.18; p=0.183).

INTERPRETATION

This meta-analysis of randomised controlled trials suggests that ARBs are associated with a modestly increased risk of new cancer diagnosis. Given the limited data, it is not possible to draw conclusions about the exact risk of cancer associated with each particular drug. These findings warrant further investigation.

Blood pressure lowering with valsartan is associated with maintenance of cerebral blood flow and cerebral perfusion reserve in hypertensive patients with cerebral small vessel disease

BACKGROUND

The purpose of this study was to determine the effect of systemic blood pressure-lowering treatment with an angiotensin II receptor blocker, valsartan, on cerebral hemodynamics in patients with hypertension and evidence of cerebral small vessel disease.

METHODS

We used positron emission tomography and acetazolamide challenge tests to measure cerebral blood flow (CBF) and cerebrovascular reserve (CVR) in 8 patients with hypertension (mean age 70.8 years) with lacunar infarcts and white matter lesions before and after valsartan therapy.

RESULTS

Systemic blood pressure was significantly decreased from baseline after treatment with valsartan. The baseline global CBFs before and after treatment were 38.2 +/- 5.6 mL/min/100 g and 39.9 +/- 9.0 mL/min/100 g, respectively. The CVRs before and after treatment were 52.2 +/- 18.4% and 39.7 +/- 18.9%, respectively. Differences in these parameters were not significant. Both regional CBF and CVR in the corona radiata with moderate or severe white matter lesions were also preserved after valsartan therapy compared with those before treatment.

CONCLUSIONS

Cerebral hemodynamics were preserved after blood pressure lowering with valsartan therapy. Valsartan could be a feasible antihypertensive regimen in terms of cerebral circulation in patients with cerebral small vessel disease.

Olmesartan inhibits angiotensin II-Induced migration of vascular smooth muscle cells through Src and mitogen-activated protein kinase pathways

Clinical studies have shown that angiotensin-receptor blockers (ARBs) reduce the risk of cardiovascular diseases in hypertensive patients. It is assumed that the reduction of the risk by ARBs may be attributed in part to the inhibition of angiotensin II (AII)-induced vascular smooth muscle cell (VSMC) migration associated with atherosclerosis. However, the effect of ARBs on AII-induced changes in intracellular signaling and resultant cell migration has not been well established. Here, we investigated the effect of olmesartan, an ARB, on AII-induced extracellular signal-regulated kinases 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK) activation and rat aortic smooth muscle cell (RASMC) migration. Olmesartan inhibited AII-induced ERK1/2 and JNK activation at lower concentrations (10 nM). On the other hand, PP2, a Src tyrosine kinase inhibitor, also inhibited AII-induced ERK1/2 and JNK activation, but its effect on ERK1/2 was less pronounced than that of olmesartan. Olmesartan, U0126 (an ERK1/2 inhibitor), SP600125 (a JNK inhibitor), and PP2 potently inhibited AII-induced RASMC migration. From these findings, it was inferred that angiotensin-receptor blockade by olmesartan results in the inhibition of AII-induced activation of Src, ERK1/2, and JNK in RASMC. Olmesartan may be a potent inhibitor of AII-induced VSMC migration, which may be involved in the progression of atherosclerosis.

Evidence for the efficacy of ARBs across the cardiovascular continuum

INTRODUCTION

Angiotensin II receptor blockers (ARBs) are antihypertensive agents with considerable evidence of efficacy and safety for the reduction of cardiovascular (CV) disease risk in numerous patient populations from one end of the CV continuum (i.e., primary prevention among patients with CV risk factors) to the other (i.e., secondary prevention in the post-MI setting). There are several agents within the ARB class, all of which have contributed to various degrees to this evidence base.

SCOPE

This review presents the design and main results of large, well designed studies examining the CV risk-reducing properties of ARBs. The authors searched major literature databases (Embase, Medline, PubMed) for randomized, controlled studies published between January, 1995 and October, 2009 that compared ARBs with placebo or active controls and reported major CV outcomes (e.g., myocardial infarction, stroke) and/or mortality as the primary study endpoint(s).

LIMITATIONS

Although many trials evaluating similar agents are presented, between-trial comparisons are inappropriate. The results of each study stand on their own merits and weaknesses, but do not provide any additional insight into the results of the other studies.

RESULTS

Agents in the ARB class have demonstrated efficacy in reducing CV events and/or mortality in a number of different patient populations, from primary prevention studies in patients with pre-specified risk factors (e.g., hypertension and left-ventricular hypertrophy in the LIFE study) to secondary prevention (i.e., post-MI patients in the VALIANT study). Some studies have also demonstrated the statistical equivalence of ARBs to ACE inhibitors in certain populations (e.g., among post-MI patients in VALIANT and among a broad population of patients with vascular disease or diabetes in the ONTARGET). There are several major studies currently underway that will provide further information on the risk-reducing properties of ARBs in additional populations (e.g., patients with impaired glucose tolerance in the NAVIGATOR study).

CONCLUSIONS

ARBs have demonstrated efficacy in reducing CV morbidity and mortality in a broad spectrum of CV disease states across the CV continuum. Ongoing research continues to provide additional evidence, with ongoing trials investigating their role in additional patient populations.

Comparing angiotensin II receptor blockers on benefits beyond blood pressure

The renin-angiotensin-aldosterone system (RAAS) is one of the main regulators of blood pressure, renal hemodynamics, and volume homeostasis in normal physiology, and contributes to the development of renal and cardiovascular (CV) diseases. Therefore, pharmacologic blockade of RAAS constitutes an attractive strategy in preventing the progression of renal and CV diseases. This concept has been supported by clinical trials involving patients with hypertension, diabetic nephropathy, and heart failure, and those after myocardial infarction. The use of angiotensin II receptor blockers (ARBs) in clinical practice has increased over the last decade. Since their introduction in 1995, seven ARBs have been made available, with approved indications for hypertension and some with additional indications beyond blood pressure reduction. Considering that ARBs share a similar mechanism of action and exhibit similar tolerability profiles, it is assumed that a class effect exists and that they can be used interchangeably. However, pharmacologic and dosing differences exist among the various ARBs, and these differences can potentially influence their individual effectiveness. Understanding these differences has important implications when choosing an ARB for any particular condition in an individual patient, such as heart failure, stroke, and CV risk reduction (prevention of myocardial infarction). A review of the literature for existing randomized controlled trials across various ARBs clearly indicates differences within this class of agents. Ongoing clinical trials are evaluating the role of ARBs in the prevention and reduction of CV rates of morbidity and mortality in high-risk patients.

Role of valsartan, amlodipine and hydrochlorothiazide fixed combination in blood pressure control: an update

The treatment of moderate or severe hypertension in most cases requires the contemporaneous use of multiple antihypertensive agents. The most available two-drug combinations have an agent that addresses renin secretion and another one that is statistically more effective in renin-independent hypertension. The practice of combining agents that counteract different mechanisms is the most likely explanation for the fact that most available two-drug combinations have an agent that addresses renin secretion (beta-blocker, angiotensin converting enzyme inhibitor, angiotensin II receptor blocker or direct renin inhibitor) and another one that is more effective in renin-independent hypertension (diuretic, dihydropyridine or non-dihydropyridine calcium channel blocker). Based on these considerations, addition of hydrochlorothiazide to the combination of an antagonist of the renin-angiotensin system with a calcium channel blocker would constitute a logical approach. Inclusion of a diuretic in the triple combination is based on the evidence that these agents are effective and cheap, enhance the effect of other antihypertensive agents, and add a specific effect to individuals with salt-sensitivity of blood pressure. The benefit of triple combination therapy with amlodipine, valsartan and hydrochlorothiazide over its dual component therapies has been demonstrated, and the use of a single pill will simplify therapy resulting in better blood pressure control.

Aliskiren/valsartan combination for the treatment of cardiovascular and renal diseases

Chronic activation of the renin-angiotensin-aldosterone system (RAAS) plays a key role in the development of hypertension, and cardiac and renal diseases. RAAS inhibitors, such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), improve cardiovascular and renal outcomes. However, studies have shown that residual morbidity and mortality remains high, despite current optimal treatment. More comprehensive control of the RAAS might provide additional reductions in morbidity and mortality. Direct renin inhibitors offer the potential for enhanced RAAS control as they target the system at the point of activation, thereby reducing plasma renin activity (PRA); by contrast, ARBs and ACE inhibitors increase PRA. Elevated PRA is independently associated with cardiovascular morbidity and mortality. A single-pill combination of the direct renin inhibitor, aliskiren, and the ARB, valsartan, at once-daily doses of 150/160 mg and 300/320 mg, has recently been approved by the US FDA for the treatment of hypertension in patients not adequately controlled on aliskiren or ARB monotherapy, and as initial therapy in patients likely to need multiple drugs to achieve their blood pressure goals. This article examines the efficacy, safety and tolerability of aliskiren/valsartan combination therapy, and considers the evidence for the potential organ-protection benefits of this treatment.

Angiotensin receptor blockers in hypertension. New insights from Japan

Angiotensin II receptor blockers (ARBs) are widely used in the treatment of patients with hypertension, heart failure, diabetic nephropathy and other clinical conditions. Several intervention trials and systematic overviews showed that both angiotensin-converting enzyme inhibitors and ARBs effectively reduce the risk of stroke, myocardial infarction and congestive heart failure in hypertensive patients. Two recent intervention trials conducted in Japan (JIKEI and Kyoto studies) suggested that the protective effect of ARBs on major cardiovascular events might be partly independent from the degree of blood pressure (BP) reduction. Both studies used a prospective randomized open blinded end point (PROBE) design. No significant differences emerged in both studies between the ARB group (valsartan) and the control group in the achieved BP. We made a pooled analysis of the JIKEI and Kyoto studies. Overall, valsartan significantly reduced the risk of the primary composite outcome (by 42%; P<0.0001), angina pectoris (by 38%; P<0.0001), heart failure requiring hospitalization (by 43%; P=0.013) and cerebrovascular events (by 42%; P=0.002). The protective effect on the dissecting aneurysm of aorta bordered statistical significance. These data reinforce the notion that the protective effect of angiotensin II inhibition is partly independent of BP reduction.

A novel method to adjust efficacy estimates for uptake of other active treatments in long-term clinical trials

BACKGROUND

When rates of uptake of other drugs differ between treatment arms in long-term trials, the true benefit or harm of the treatment may be underestimated. Methods to allow for such contamination have often been limited by failing to preserve the randomization comparisons. In the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study, patients were randomized to fenofibrate or placebo, but during the trial many started additional drugs, particularly statins, more so in the placebo group. The effects of fenofibrate estimated by intention-to-treat were likely to have been attenuated. We aimed to quantify this effect and to develop a method for use in other long-term trials.

METHODOLOGY/PRINCIPAL FINDINGS

We applied efficacies of statins and other cardiovascular drugs from meta-analyses of randomized trials to adjust the effect of fenofibrate in a penalized Cox model. We assumed that future cardiovascular disease events were reduced by an average of 24% by statins, and 20% by a first other major cardiovascular drug. We applied these estimates to each patient who took these drugs for the period they were on them. We also adjusted the analysis by the rate of discontinuing fenofibrate. Among 4,900 placebo patients, average statin use was 16% over five years. Among 4,895 assigned fenofibrate, statin use was 8% and nonuse of fenofibrate was 10%. In placebo patients, use of cardiovascular drugs was 1% to 3% higher. Before adjustment, fenofibrate was associated with an 11% reduction in coronary events (coronary heart disease death or myocardial infarction) (P = 0.16) and an 11% reduction in cardiovascular disease events (P = 0.04). After adjustment, the effects of fenofibrate on coronary events and cardiovascular disease events were 16% (P = 0.06) and 15% (P = 0.008), respectively.

CONCLUSIONS/SIGNIFICANCE

This novel application of a penalized Cox model for adjustment of a trial estimate of treatment efficacy incorporates evidence-based estimates for other therapies, preserves comparisons between the randomized groups, and is applicable to other long-term trials. In the FIELD study example, the effects of fenofibrate on the risks of coronary heart disease and cardiovascular disease events were underestimated by up to one-third in the original analysis.

TRIAL REGISTRATION

Controlled-Trials.com ISRCTN64783481.

Effects of angiotensin II receptor blockers on dementia

The renin-angiotensin system (RAS) is involved in pathological mechanisms of target organ damage as well as the induction of hypertension; therefore, blockade of the RAS has been expected to prevent cardiovascular and cerebrovascular diseases beyond its antihypertensive effects. In spite of the well-characterized role of angiotensin (Ang) II receptor blockers (ARBs) in preventing the onset and recurrence of stroke, the clinical evidence for an effect of ARBs on dementia has not been definitive. However, preliminary experiments raise the possibility that treatment using ARBs may prevent ischemic brain damage and cognitive impairment. Moreover, recent reports have shown that some ARBs prevent amyloid beta deposition in the brain and attenuate cognitive impairment in Alzheimer disease models. Furthermore, recent cohort studies indicate that lower incidence of Alzheimer disease is observed in elderly individuals treated with ARBs. These results indicate a beneficial role for ARBs in cognitive impairment associated with vascular disease, Alzheimer disease, metabolic syndrome and other neurodegenerative diseases. Here, we review the effects of ARBs on the brain with a focus on dementia and future therapeutic approaches for elderly people suffering from disabilities.