Effects of hypertension therapy based on eprosartan on systolic arterial blood pressure and cognitive function: primary results of the Observational Study on Cognitive function And Systolic Blood Pressure Reduction open-label study

Angiotensin Receptor Blockers and Cognition: a Scoping Review

PURPOSE OF REVIEW

To provide an overview of the association between angiotensin II receptor blocker (ARB) use and cognitive outcomes.

RECENT FINDINGS

ARBs have previously shown greater neuroprotection compared to other anti-hypertensive classes. The benefits are primarily attributed to the ARB's effect on modulating the renin-angiotensin system via inhibiting the Ang II/AT1R pathway and activating the Ang II/AT2R, Ang IV/AT4R, and Ang-(1-7)/MasR pathways. These interactions are associated with pleiotropic neurocognitive benefits, including reduced β-amyloid accumulation and abnormal hyperphosphorylation of tau, ameliorated brain hypo-fusion, reduced neuroinflammation and synaptic dysfunction, better neurotoxin clearing, and blood-brain barrier function restoration. While ACEis also inhibit AT1R, they simultaneously lower Ang II and block the Ang II/AT2R and Ang IV/AT4R pathways that counterbalance the potential benefits. ARBs may be considered an adjunctive approach for neuroprotection. This preliminary evidence, coupled with their underlying mechanistic pathways, emphasizes the need for future long-term randomized trials to yield more definitive results.

Effect of blood pressure on mortality in patients with cognitive impairment: a prospective cohort study

Background

Cognitive impairment is a prevalent condition that substantially elevates mortality rates among the elderly. The impact of hypertension on mortality in older adults with cognitive impairment is a subject of contention. This study aims to examine the influence of hypertension on both all-cause and CVD-specific mortality in elderly individuals experiencing cognitive impairment within a prospective cohort.

Methods

This study encompassed 2,925 participants (weighted 53,086,905) aged 60 years or older from National Health and Nutrition Examination Survey (NHANES) spanning 2011-2014. Incidence of all-cause and CVD-specific mortality was ascertained through linkage with National Death Index records until 31 December 2019. Survival was performed employing the Kaplan-Meier method. Hazard ratios (HRs) were calculated via Cox proportional hazards regression models.

Results

Over the follow-up period of up to 9.17 years [with a median (IQR) time to death of 6.58 years], equivalent to 18,731.56 (weighted 3.46 × 108) person-years, there were a total of 576 recorded deaths. Participants with CI exhibited a 1.96-fold higher risk of all-cause mortality (95% CI: 1.55-2.49; p < 0.01) and a 2.8-fold higher risk of CVD-specific mortality (95% CI: 1.83-4.29; p < 0.01) in comparison to participants without CI. Among participants with CI, concurrent hypertension comorbidity was linked to a 2.73-fold elevated risk of all-cause mortality (95% CI: 1.78-4.17; p < 0.01) and a 5.3-fold elevated risk of CVD-specific mortality (95% CI: 2.54-11.04; p < 0.01). Further stratified analyses revealed that the combined effects of hypertension and CI on all-cause and CVD-specific mortality were more pronounced in participants aged 60-69 years compared to those aged 70-80 years (p for interaction <0.01). The primary findings exhibited resilience across a series of sensitivity analyses.

Conclusions

Participants with CI exhibited a markedly elevated risk of all-cause and CVD-specific mortality when coexisting with hypertension. Appropriate management of hypertension in patients with CI may be helpful in reducing the excess risk of death.

Therapeutic Implications of Renin-Angiotensin System Modulators in Alzheimer's Dementia

The Renin-Angiotensin System (RAS) has attracted considerable interest beyond its traditional cardiovascular role due to emerging data indicating its potential involvement in neurodegenerative diseases, including Alzheimer's dementia (AD). This review investigates the therapeutic implications of RAS modulators, specifically focusing on angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and renin inhibitors in AD. ACEIs, commonly used for hypertension, show promise in AD by reducing angiotensin (Ang) II levels. This reduction is significant as Ang II contributes to neuroinflammation, oxidative stress, and β-amyloid (Aβ) accumulation, all implicated in AD pathogenesis. ARBs, known for vasodilation, exhibit neuroprotection by blocking Ang II receptors, improving cerebral blood flow and cognitive decline in AD models. Renin inhibitors offer a novel approach by targeting the initial RAS step, displaying anti-inflammatory and antioxidant effects that mitigate AD degeneration. Preclinical studies demonstrate RAS regulation's favorable impact on neuroinflammation, neuronal damage, cognitive function, and Aβ metabolism. Clinical trials on RAS modulators in AD are limited, but with promising results, ARBs being more effective that ACEIs in reducing cognitive decline. The varied roles of ACEIs, ARBs, and renin inhibitors in RAS modulation present a promising avenue for AD therapeutic intervention, requiring further research to potentially transform AD treatment strategies.

Effects of intensive vs. standard blood pressure control on cognitive function: Post-hoc analysis of the STEP randomized controlled trial

Background

The STEP (Strategy of Blood Pressure Intervention in the older Hypertensive Patients) trial showed that intensive systolic blood pressure (SBP) control resulted in a lower incidence of cardiovascular events than standard treatment. This study analyzed the effects of intensive SBP lowering on cognitive function.

Methods

STEP was a multicenter, randomized controlled trial of hypertensive patients aged 60-80 years. Participants were randomly assigned (1:1) to SBP goals of 110-130 mmHg (intensive treatment) or 130-150 mmHg (standard treatment). Each individual was asked to complete a cognitive function test (Mini-Mental State Examination; MMSE) at baseline and during follow-up. The primary outcome for this study was the annual change in MMSE score. Subjects with a score less than education-specific cutoff point were categorized as cognitive decline.

Results

The analysis enrolled 6,501 participants (3,270 participants in the intensive-treatment and 3,231 participants in the standard-treatment groups). Median follow-up was 3.34 years. There was a minor change in MMSE score, with an annual change of -0.001 [95% confidence interval [CI] -0.020, 0.018] and 0.030 (95% CI 0.011, 0.049) in the intensive- and standard-treatment groups, respectively (p = 0.052). Cognitive decline occurred in 46/3,270 patients (1.4%) in the intensive-treatment group and 42/3,231 (1.3%) in the standard-treatment group (hazard ratio 0.005, 95% CI 0.654, 1.543, p = 0.983).

Conclusions

Compared with standard treatment, intensive SBP treatment did not result in a significant change in cognitive function test score. The impact of intensive blood pressure lowering was not evident using this global cognitive function test.

Trial registration

ClinicalTrials.gov. Unique identifier: NCT03015311.

Antihypertensive therapy is associated with improved visuospatial, executive, attention, abstraction, memory, and recall scores on the montreal cognitive assessment in geriatric hypertensive patients

Background

The prevalence of Mild Cognitive Impairment (MCI) has increased over the past few decades. However, it can potentially be reversed if detected early. Early detection of MCI using the sensitive Montreal Cognitive Assessment (MoCA) might prove to be an important cog in the wheel in identifying and slowing down this morbid pandemic in hypertensive persons.

Objectives

To study the association of antihypertensive agents on cognitive scores and prevalence of MCI using the MoCA.

Materials and methods

This is a single-center, controlled, observational, cross-sectional study in a tertiary care teaching hospital in India. Cognitive assessment was done using the Montreal Cognitive Assessment. Data on MoCA scores were comprehensively analyzed.

Results

A total of N = 210 patients (n = 105 the in study and control groups) were included in the study. The median (IQR) MoCA score (out of 30 points) in patients taking antihypertensives was 26 (25 - 27), while it was 24 (22 - 25) in the control group. There was no difference in MoCA scores between patients taking lipophilic or hydrophilic antihypertensives. Similarly, there was no difference in MoCA scores between patients taking different drug regimens.

Conclusion

Anti-hypertensive therapy and lower blood pressure had a statistically significant positive association with visuospatial, executive, attention, abstraction, memory, and recall MoCA scores. Patients on antihypertensive therapy also had a lower prevalence of MCI. MoCA scores were similar in patients on either lipophilic or hydrophilic drugs and were similar between patients on different antihypertensive drug classes.

Angiotensin II Receptor Blockers in the Management of Hypertension in Preventing Cognitive Impairment and Dementia-A Systematic Review

Hypertension is a known risk factor for cognition-related pathologies including dementia. The National Institute of Health and Care Excellence (NICE) guidelines recommend angiotensin (Ang) II receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) as a first-line treatment for hypertension. Although both ARBs and ACEIs show neuroprotective effects, ACEIs show contradictory side effects; therefore, ARBs may be a more viable option. However, trials assessing the effects of ARBs on cognition are scarce and conflicting. Therefore, the aim of this review is to conduct a systematic review and synthesise data on the influence of ARBs on cognition and dementia prevention. Five databases were searched from 1992-2022 to produce 13 randomised controlled trials (RCTs) involving 26,907 patients that compared associations of ARBs against placebos or other antihypertensives on cognition or probable dementia with a minimum duration of 3 months. ARBs showed greater cognitive benefits when compared to hydrochlorothiazide (HCTZ), beta blockers (BB), and ACEIs. Our findings showed that although ARBs are superior to some antihypertensives such as ACEIs, thiazide and beta blockers, they made no difference in comparison to the placebo in all but one sample of patients. The positive effects on cognitive performances are equal to calcium channel blockers (CCBs) and lower than statin. The neuroprotective effects of ARBs are also more beneficial when ARBs are taken at the same time as a statin. Due to these inconsistencies, robust conclusions cannot be made. Future trials are warranted and, if successful, could have positive economic implications and consequently improve quality of life.

Recent Advances in the Endogenous Brain Renin-Angiotensin System and Drugs Acting on It

The RAS (renin-angiotensin system) is the part of the endocrine system that plays a prime role in the control of essential hypertension. Since the discovery of brain RAS in the seventies, continuous efforts have been put by the scientific committee to explore it more. The brain has shown the presence of various components of brain RAS such as angiotensinogen (AGT), converting enzymes, angiotensin (Ang), and specific receptors (ATR). AGT acts as the precursor molecule for Ang peptides—I, II, III, and IV—while the enzymes such as prorenin, ACE, and aminopeptidases A and N synthesize it. AT1, AT2, AT4, and mitochondrial assembly receptor (MasR) are found to be plentiful in the brain. The brain RAS system exhibits pleiotropic properties such as neuroprotection and cognition along with regulation of blood pressure, CVS homeostasis, thirst and salt appetite, stress, depression, alcohol addiction, and pain modulation. The molecules acting through RAS predominantly ARBs and ACEI are found to be effective in various ongoing and completed clinical trials related to cognition, memory, Alzheimer's disease (AD), and pain. The review summarizes the recent advances in the brain RAS system highlighting its significance in pathophysiology and treatment of the central nervous system-related disorders.

Blood Pressure Levels and Risks of Dementia: a Nationwide Study of 4.5 Million People

There are inconsistent results on the impacts of controlling blood pressure (BP) on the risk of dementia. We investigated the association between BP and risk of dementia subtypes by antihypertensive treatment and comorbidities. Using the Korean National Health Insurance Service-Health Screening Database from 2009 to 2012, a total of 4 522 447 adults aged 60+ years without a history of dementia were analyzed and followed up for a mean of 5.4 years. Individuals were classified according to their baseline systolic BP (SBP) and diastolic BP; SBP 130 to <140 mm Hg and diastolic BP 80 to <90 mm Hg were used as reference groups. The risk of overall dementia and probable Alzheimer disease was significantly higher in the SBP≥160 and lower SBP groups. These U-shaped associations were consistent regardless of antihypertensive use or comorbidities. The risk of probable vascular dementia (VaD) was not higher among lower SBP groups and increased gradually as SBP increased. Although there was a linear association between SBP and the risk of probable VaD in individuals not taking antihypertensives or without comorbidities, there was a U-shaped association in individuals taking antihypertensives or with comorbidities. Patterns of association between diastolic BP and risk of probable Alzheimer disease or probable VaD were similar to those with SBP, except for the risk of probable VaD in individuals taking antihypertensives. In conclusion, risks of probable Alzheimer disease and probable VaD were different among lower BP groups. Although the risk of dementia appears higher in people with lower BP receiving antihypertensives, this finding may be affected by comorbidities.

Arterial hypertension and antihypertensive therapy in older patients. The agreed opinion of experts from the Russian Association of Gerontologists and Geriatricians, the Antihypertensive League, the National Society for Preventive Cardiology

High blood pressure is a risk factor for cardiovascular morbidity and mortality, as well as cognitive decline and loss of autonomy in the elderly and old age. Randomized clinical trials (RCTs) in populations of older patients living at home with low comorbidity and preserved autonomy indicate the benefit of lowering elevated blood pressure in patients over 80 years of age. Older patients with senile asthenia, loss of autonomy and other geriatric problems were excluded from RCTs, and observational studies in these groups of patients indicate an increase in morbidity and mortality with lower blood pressure and antihypertensive therapy. Obviously, in very elderly patients, a universal strategy for the treatment of arterial hypertension cannot be applied due to the significant heterogeneity of their functional status. The geriatric approach to the management of arterial hypertension in older patients involves an assessment of the functional status, the presence of senile asthenia, and the degree of autonomy for the choice of antihypertensive therapy tactics.

Long-term effect of masked hypertension management on cognitive functions in geriatric age: geriatric MASked hypertension and cognition follow-up study (G-MASH-cog MONITOR)

OBJECTIVES

Masked hypertension, defined as nonelevated clinic blood pressure with elevated out of clinic blood pressure, has been associated with increased cardiovascular events, mortality and cognitive impairment. No evidence exists regarding the effect of treating masked hypertension. In this study, we followed-up the patients in the G-MASH-cog study for 1 year and aimed to examine the effect of the management of masked hypertension on cognitive functions.

METHODS

The G-MASH-cog study participants were followed-up for 1 year. In masked hypertensive individuals, lifestyle modification and antihypertensive treatment (perindopril or amlodipine) were initiated for blood pressure control. Measurements of cognitive tests and ambulatory blood pressure monitoring at baseline and at 1-year follow-up were compared.

RESULTS

A total of 61 patients (30 in masked hypertension group; 31 in normotensive group) were included. Mean age was 72.3 ± 5.1 and 59% of the participants were female. Compared with baseline ambulatory blood pressure measurement results, patients with masked hypertension had significantly lower ambulatory blood pressure measurement results after 1-year follow-up. The quick mild cognitive impairment test (Q-MCI-TR) score increased with antihypertensive treatment (Q-MCI score at baseline = 41(19-66.5), at 1 year = 45.5 (22-70), P = 0.005) in masked hypertensive patients. In the final model of the mixed-effects analysis, when adjusted for covariates, interaction effect of the masked hypertension treatment with time was only significant in influencing the changes in Q-MCI scores over time in patients aged between 65 and 74 years (P = 0.002).

CONCLUSIONS

Treatment of masked hypertension in older adults was associated with improvement in cognitive functions.

Modifiable Risk Factors in Alzheimer Disease and Related Dementias: A Review

PURPOSE

Although Alzheimer disease and related dementias (ADRDs) have long been considered nonpreventable and even an inevitable consequence of aging, recent findings from longitudinal studies indicate a downtrend in age-adjusted incidence and prevalence of ADRDs in Western countries. This remarkable trend might be the result of improved management of so-called modifiable risk factors. The aim of this review is to present evidence of modifiable factors of ADRDs in a life-course approach.

METHODS

A PubMed database search was conducted between November and December 2020 to identify relevant studies evaluating the role of modifiable risk factors in the development of ADRDs. Key words (Alzheimer's disease and modifiable risk factors) were used and specific inclusion and exclusion criteria applied.

FINDINGS

This review identifies modifiable factors for ADRDs divided into early-life, middle-life, and late-life risk factors, depending on the available window of preventive action. According to life course exposure, factors can be protective or deleterious for ADRDs that participate in the underlying pathophysiologic complexity of these diseases as well as the complexity for public health measures implementations.

IMPLICATIONS

The available evidence derived from epidemiologic, preclinical, interventional studies suggest that modifiable risk factors for ADRDs offer opportunities for therapeutic and preventive actions.

Effects of Antihypertensive Drugs on Cognitive Function in Elderly Patients with Hypertension: A Review

Hypertension is a common comorbidity that contributes to the development of various cardiovascular disorders in elderly patients. Moreover, hypertension has been associated with cognitive decline and dementia. Cognitive impairment leads to increased morbidity and mortality in elderly patients with hypertension. However, previous studies investigating the association between blood pressure (BP), BP variability (BPV), and antihypertensive drug use and the risk of cognitive impairment in elderly patients with hypertension have reported inconsistent findings. Given the global burden of hypertension, the aging population, and the low quality of life associated with cognitive impairment, a more comprehensive understanding of the association between hypertension and cognitive decline is needed. In this review, we summarized the current preclinical evidence and clinical research regarding the association of BP control, BPV, and antihypertensive drug use and cognitive function. We particularly focused on the differences among categories of antihypertensive drugs. We concluded that the correlation of BP and risk of cognitive function is non-linear and dependent on a patient’s age. Intensive BP control is generally not recommended, particularly for the oldest-old. Increased BPV and characteristics of orthostatic hypotension in the elderly also increase the risk of cognitive decline. The current evidence does not support one category of antihypertensive drugs as superior to others for preventing dementia in elderly patients with hypertension.

The Brain AT2R-a Potential Target for Therapy in Alzheimer's Disease and Vascular Cognitive Impairment: a Comprehensive Review of Clinical and Experimental Therapeutics

Dementia is a potentially avertable tragedy, currently considered among the top 10 greatest global health challenges of the twenty-first century. Dementia not only robs individuals of their dignity and independence, it also has a ripple effect that starts with the inflicted individual's family and projects to the society as a whole. The constantly growing number of cases, along with the lack of effective treatments and socioeconomic impact, poses a serious threat to the sustainability of our health care system. Hence, there is a worldwide effort to identify new targets for the treatment of Alzheimer's disease (AD), the leading cause of dementia. Due to its multifactorial etiology and the recent clinical failure of several novel amyloid-β (Aβ) targeting therapies, a comprehensive "multitarget" approach may be most appropriate for managing this condition. Interestingly, renin angiotensin system (RAS) modulators were shown to positively impact all the factors involved in the pathophysiology of dementia including vascular dysfunction, Aβ accumulation, and associated cholinergic deficiency, in addition to tau hyperphosphorylation and insulin derangements. Furthermore, for many of these drugs, the preclinical evidence is also supported by epidemiological data and/or preliminary clinical trials. The purpose of this review is to provide a comprehensive update on the major causes of dementia including the risk factors, current diagnostic criteria, pathophysiology, and contemporary treatment strategies. Moreover, we highlight the angiotensin II receptor type 2 (AT2R) as an effective drug target and present ample evidence supporting its potential role and clinical applications in cognitive impairment to encourage further investigation in the clinical setting.

Hypertension-induced subclinical vascular and cognitive changes are reversible-An observational cohort study

Beside the well-known complications of poorly controlled, long-standing hypertension, milder abnormalities induced by early-stage hypertension have also been described. In our study, the authors examined the reversibility of changes induced by early-stage hypertension. The authors performed laboratory testing, ambulatory blood pressure monitoring, carotid intima-media thickness (IMT) measurement, evaluation of stiffness parameters, assessment of various cardiac and cerebral hemodynamic parameters during head-up tilt table (HUTT) testing, and neuropsychological examinations in 49 recently diagnosed hypertensive patients. Following baseline assessment, antihypertensive therapy was commenced. After one year of therapy, lower IMT values were found. Pulse wave velocity showed a borderline significant decrease. During HUTT, several hemodynamic parameters improved. The patients performed better on neuropsychological testing and reached significantly lower scores on questionnaires evaluating anxiety. The present study shows that early vascular changes and altered cognitive function observed in newly diagnosed hypertensive patients may improve with promptly initiated antihypertensive management.

The association of multiple anti-hypertensive medication classes with Alzheimer's disease incidence across sex, race, and ethnicity

BACKGROUND

Antihypertensive treatments have been shown to reduce the risk of Alzheimer's disease (AD). The renin-angiotensin system (RAS) has been implicated in AD, and thus RAS-acting AHTs (angiotensin converting enzyme inhibitors (ACEIs), and angiotensin-II receptor blockers (ARBs)) may offer differential and additional protective benefits against AD compared with other AHTs, in addition to hypertension management.

METHODS

In a retrospective cohort design, we examined the medical and pharmacy claims of a 20% sample of Medicare beneficiaries from 2007 to 2013, and compared rates of AD diagnosis for 1,343,334 users of six different AHT drug treatments, 65 years of age or older (4,215,338 person-years). We compared AD risk between RAS and non-RAS AHT drug users, and between ACEI users and ARB users, by sex and race/ethnicity. Models adjusted for age, socioeconomic status, underlying health, and comorbidities.

FINDINGS

RAS-acting AHTs were slightly more protective against onset of AD than non-RAS-acting AHTs for males, (male OR = 0.931 (CI: 0.895-0.969)), but not so for females (female OR = 0.985 (CI: 0.963-1.007)). Relative to other AHTs, ARBs were superior to ACEIs for both men (male ARB OR = 0.834 (CI: 0.788-0.884); male ACEI OR = 0.978 (CI: 0.939-1.019)) and women (female ARB OR = 0.941 (CI: 0.913-0.969); female ACEI OR = 1.022 (CI: 0.997-1.048)), but only in white men and white and black women. No association was shown for Hispanic men and women.

CONCLUSION

Hypertension management treatments that include RAS-acting ARBs may, in addition to lowering blood pressure, reduce AD risk, particularly for white and black women and white men. Additional studies and clinical trials that include men and women from different racial and ethnic groups are needed to confirm these findings. Understanding the potentially beneficial effects of certain RAS-acting AHTs in high-risk populations is of great importance.

Effects of a new nutraceutical combination on cognitive function in hypertensive patients

Background

Chronic increased arterial blood pressure has been associated with executive dysfunction, slowing of attention and mental processing speed, and later with memory deficits. Due to the absence of a concrete therapeutic approach to this pathophysiological process, in the last decades there has been an increasing interest in the use of nutraceuticals, especially those with antioxidant properties, which own strong neuroprotective potential, that may help to improve cognitive function and to delay the onset of dementia.

Results

We evaluated the effects of the treatment with a new nutraceutical preparation containing different molecules with potent antioxidant properties (AkP05, IzzeK®) and placebo on a cohort of thirty-six hypertensive patients. At baseline, neuropsychological evaluation, arterial stiffness and biochemical parameters of the subjects were comparable. After 6 months of treatment, there was a significant reduction of the augmentation index in the AkP05-treated group. Moreover, the measurement of cognitive function, evaluated with MoCA test and Word Match Testing, showed a significant improvement in patients receiving the active treatment. In addition, the group treated with nutraceutical reached a better Stroop test score, while subjects that received placebo did not showed any improvement. Finally, a positive relationship between SBP variation and the psychometric assessment with the EQ-VAS scale was observed only in the active treatment group.

Conclusions

In this study, we demonstrated that the therapy with a new nutraceutical preparation is able to significantly increase the scores of important neuropsychological tests in hypertensive patients already on satisfactory blood pressure control. Although future studies are needed to better characterize the molecular mechanisms involved, these results candidate the new nutraceutical combination as a possible therapeutic strategy to support the cerebrovascular functions and delay the onset of dementia in hypertensive patients.

Carotid artery stenosis in hypertensive rats impairs dilatory pathways in parenchymal arterioles

Hypertension is a leading risk factor for vascular cognitive impairment and is strongly associated with carotid artery stenosis. In normotensive rats, chronic cerebral hypoperfusion induced by bilateral common carotid artery stenosis (BCAS) leads to cognitive impairment that is associated with impaired endothelium-dependent dilation in parenchymal arterioles (PAs). The aim of this study was to assess the effects of BCAS on PA function and structure in stroke-prone spontaneously hypertensive rats, a model of human essential hypertension. Understanding the effects of hypoperfusion on PAs in a hypertensive model could lead to the identification of therapeutic targets for cognitive decline in a model that reflects the at-risk population. We hypothesized that BCAS would impair endothelium-dependent dilation in PAs and induce artery remodeling compared with sham rats. PAs from BCAS rats had endothelial dysfunction, as assessed using pressure myography. Inhibition of nitric oxide and prostaglandin production had no effect on PA dilation in sham or BCAS rats. Surprisingly, inhibition of epoxyeicosatrienoic acid production increased dilation in PAs from BCAS rats but not from sham rats. Similar results were observed in the presence of inhibitors for all three dilatory pathways, suggesting that epoxygenase inhibition may have restored a nitric oxide/prostaglandin-independent dilatory pathway in PAs from BCAS rats. PAs from BCAS rats underwent remodeling with a reduced wall thickness. These data suggest that marked endothelial dysfunction in PAs from stroke-prone spontaneously hypertensive rats with BCAS may be associated with the development of vascular cognitive impairment. NEW & NOTEWORTHY The present study assessed the structure and function of parenchymal arterioles in a model of chronic cerebral hypoperfusion and hypertension, both of which are risk factors for cognitive impairment. We observed that impaired dilation and artery remodeling in parenchymal arterioles and abolished cerebrovascular reserve capacity may mediate cognitive deficits.

Treatment options and considerations for hypertensive patients to prevent dementia

INTRODUCTION

Dementia is a worldwide health concern, which leads to loss of autonomy. To date no curative treatment is available so focus on modifiable risk factors is of particular interest. Hypertension, particularly midlife high blood pressure, has been associated with an increased risk for cognitive decline and dementia including vascular dementia (VAD) and Alzheimer disease (AD). In this context, antihypertensive treatments might have a preventive effect. The objective of this review was to examine the relationship between antihypertensive therapy and cognitive decline or dementia. Areas covered: A literature search was conducted using PUBMED and the COCHRANE LIBRARY for publications from 1990 onwards mentioning cognitive decline, AD, Vad, mixed dementia, vascular cognitive impairment, hypertension and antihypertensive therapy. Thirty-nine relevant publications including 20 longitudinal studies, 10 randomized-controlled trials and 9 meta-analyses were taken into account. Expert opinion: Most observational studies have suggested a potential preventive effect of antihypertensive therapies on cognitive decline and dementia, particularly calcium channel blockers and renin-angiotensin system blockers. Randomized clinical trials and meta-analyses provided more conflicting results potentially due to methodological issues. In conclusion, antihypertensive therapies may reduce cognitive decline and incidence of dementia. Further randomized clinical trials conducted in populations at higher risk of cognitive decline, with longer periods of follow-up and cognition as the primary outcome are still needed.

Older Adults Taking AT1-Receptor Blockers Exhibit Reduced Cerebral Amyloid Retention

BACKGROUND

Evidence suggests that angiotensin II AT1-receptor blockers (ARBs) may be protective against dementia, and studies in transgenic animals indicate that this may be due to improved amyloid-β (Aβ) clearance.

OBJECTIVE

We investigated whether taking ARBs was associated with an attenuation of age-related increases in cerebral Aβ retention, and reduced progression to dementia.

METHODS

Eight hundred seventy-one stroke-free and dementia-free older adults from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study underwent baseline lumbar puncture, and a subgroup (n = 124) underwent 12 and 24 month follow-up lumbar puncture. Participants were followed at variable intervals for clinical progression to dementia. Linear mixed models and ANCOVA compared ARBs users with those taking other antihypertensives (O-antiHTN) or no antihypertensives (No-antiHTN) on cerebrospinal fluid (CSF) Aβ and phosphorylated tau (P-tau) levels. Cox regression and chi-square analyses compared groups on progression to dementia.

RESULTS

ARBs users exhibited greater vascular risk and lower educational attainment than the No-antiHTN group. Longitudinal analyses indicated higher CSF Aβ and lower P-tau in ARBs users versus other groups. Cross-sectional analyses revealed age-related decreases in CSF Aβ in other groups but not ARBs users. ARBs users were less likely to progress to dementia and showed reduced rate of progression relative to the No-antiHTN group.

DISCUSSION

Patients taking ARBs showed an attenuation of age-related decreases in CSF Aβ, a finding that is consistent with studies done in transgenic animals. These findings may partly explain why ARBs users show reduced progression to dementia despite their lower educational attainment and greater vascular risk burden.

Strategies and Challenges in Clinical Trials Targeting Human Aging

Interventions that target fundamental aging processes have the potential to transform human health and health care. A variety of candidate drugs have emerged from basic and translational research that may target aging processes. Some of these drugs are already in clinical use for other purposes, such as metformin and rapamycin. However, designing clinical trials to test interventions that target the aging process poses a unique set of challenges. This paper summarizes the outcomes of an international meeting co-ordinated by the NIH-funded Geroscience Network to further the goal of developing a translational pipeline to move candidate compounds through clinical trials and ultimately into use. We review the evidence that some drugs already in clinical use may target fundamental aging processes. We discuss the design principles of clinical trials to test such interventions in humans, including study populations, interventions, and outcomes. As examples, we offer several scenarios for potential clinical trials centered on the concepts of health span (delayed multimorbidity and functional decline) and resilience (response to or recovery from an acute health stress). Finally, we describe how this discussion helped inform the design of the proposed Targeting Aging with Metformin study.

The Different Therapeutic Choices with ARBs. Which One to Give? When? Why?

The renin-angiotensin-aldosterone system plays an important role in the pathophysiology of hypertension and is closely related with cardio- and cerebrovascular events and chronic kidney diseases. Each angiotensin receptor blocker (ARB) is important in the treatment of hypertension, according to the results of recent years. This is a practical review of the available evidence on the different benefits of ARBs beyond their blood pressure-lowering effect, with an emphasis on the differences found between the particular compounds and the therapeutic implications of the findings, with specific reference to the co-morbidities.

Translating the Science of Aging into Therapeutic Interventions

Life and health span have been extended in experimental animals using drugs that are potentially translatable into humans. Considerable effort is needed beyond the usual steps in drug development to devise the models, and realistic preclinical and clinical trial strategies are required to advance these agents into clinical application. It will be important to focus on subjects who already have symptoms or are at imminent risk of developing disorders related to fundamental aging processes, to use short-term, clinically relevant outcomes, as opposed to long-term outcomes, such as health span or life span, and to validate endpoint measures so they are acceptable to regulatory agencies. Funding is a roadblock, as is shortage of investigators with combined expertise in the basic biology of aging, clinical geriatrics, and investigational new drug clinical trials. Strategies for developing a path from the bench to the bedside are reviewed for interventions that target fundamental aging mechanisms.

Antihypertensive drugs, prevention of cognitive decline and dementia: a systematic review of observational studies, randomized controlled trials and meta-analyses, with discussion of potential mechanisms

BACKGROUND

Chronic hypertension, particularly midlife high blood pressure, has been associated with an increased risk for cognitive decline and dementia. In this context, antihypertensive drugs might have a preventive effect, but the association remains poorly understood.

OBJECTIVES

The aim of this systematic review was to examine all published findings that investigated this relationship and discuss the mechanisms underlying the potential benefits of antihypertensive medication use.

METHODS

A literature search was conducted using MEDLINE, Embase, and the Cochrane Library for publications from 1990 onwards mentioning hypertension, antihypertensive drugs, cognitive decline, and dementia.

RESULTS

A total of 38 relevant publications, corresponding to 18 longitudinal studies, 11 randomized controlled trials, and nine meta-analyses were identified from the 10,251 articles retrieved in the literature search. In total, 1,346,176 subjects were included in these studies; the average age was 74 years. In the seven longitudinal studies assessing the effect of antihypertensive medication on cognitive impairment or cognitive decline, antihypertensive drugs appeared to be beneficial. Of the 11 longitudinal studies that assessed the effect of antihypertensive medication on incidence of dementia, only three did not find a significant protective effect. Antihypertensive medication could decrease the risk of not only vascular dementia but also Alzheimer's disease. Four randomized controlled trials showed a potentially preventive effect of antihypertensive drugs on the incidence of dementia or cognitive decline: SYST-EUR (Systolic Hypertension in Europe Study) I and II, with a 55% reduction in dementia risk (3.3 vs. 7.4 cases per 1,000 patient years; p<0.001); HOPE (Heart Outcomes Prevention Evaluation), with a 41% reduction in cognitive decline associated with stroke (95% confidence interval [CI] 6-63); and PROGRESS (Perindopril Protection against Recurrent Stroke Study), with a 19% reduction in cognitive decline (95% CI 4-32; p=0.01). Meta-analyses have sometimes produced conflicting results, but this may be due to methodological considerations. The lack of homogeneity across study designs, patient populations, exposition, outcomes, and duration of follow-up are the most important methodological limitations that might explain the discrepancies between some of these studies.

CONCLUSION

Antihypertensive drugs, particularly calcium channel blockers and renin-angiotensin system blockers, may be beneficial in preventing cognitive decline and dementia. However, further randomized controlled trials with longer periods of follow-up and cognition as the primary outcome are needed to confirm these findings.

Hypertension, brain damage and cognitive decline

Loss of cognitive function is one the most devastating manifestations of ageing and vascular disease. Cognitive decline is rapidly becoming an important cause of disability worldwide and contributes significantly to increased mortality. There is growing evidence that hypertension is the most important modifiable vascular risk factor for development and progression of both cognitive decline and dementia. High blood pressure contributes to cerebral small and large vessel disease resulting in brain damage and dementia. A decline in cerebrovascular reserve capacity and emerging degenerative vascular wall changes underlie complete and incomplete brain infarcts, haemorrhages and white matter hyperintensities. This review discusses the complexity of factors linking hypertension to brain functional and structural changes, and to cognitive decline and dementia. The evidence for possible clinical markers useful for prevention of decreased cognitive ability, as well as recent data on vascular mechanism in the pathogenesis of cognitive decline, and the role of antihypertensive therapies in long-term prevention of late-life cognitive decline will be reviewed.

Blood pressure levels and prognosis of intracranial trauma patients with cognitive dysfunction

Objective: To evaluate the effects of blood pressure levels on prognosis of intracranial trauma patients with cognitive dysfunction.

Methods: One hundred and twenty intracranial trauma patients enrolled in our hospital from February 2011 to July 2013 were selected, including 40 hypertension and 80 non-hypertension cases. They were investigated by MiniMental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scales, and the clinical data were retrospectively analyzed.

Results: Compared with the control group, the MoCA, visuospatial executive function, attention, language, delayed recall, MMSE, orientation and memory scores of the hypertension group were significantly lower. Unconditional Logistic regression analysis showed that age, history of cerebrovascular disease and triglyceride level were the independent risk factors of cognitive function.

Conclusion: The blood pressure levels of intracranial trauma patients were associated with cognitive function, with age, history of cerebrovascular disease and triglyceride level as the independent risk factors. Therefore, it is necessary to control blood pressure level to improve prognosis.

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

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

Risk factors for the progression of mild cognitive impairment to dementia

The increasing prevalence of cognitive impairment among the older adult population warrants attention to the identification of practices that may minimize the progression of early forms of cognitive impairment, including the transitional stage of mild cognitive impairment (MCI), to permanent stages of dementia. This article identifies both markers of disease progress and risk factors linked to the progression of MCI to dementia. Potentially modifiable risk factors may offer researchers a point of intervention to modify the effect of the risk factor and to minimize the future burden of dementia.

Renin-angiotensin system blocking drugs

The two major classes of drugs that target the RAS are the angiotensin-converting enzyme (ACE) inhibitors and the selective AT1 receptor blockers (ARBs). Although both of these drug classes target angiotensin II, the differences in their mechanisms of action have implications for their effects on other pathways and receptors that may have therapeutic implications. Both ACEIs and ARBs are effective antihypertensive agents that have been shown to reduce the risk of cardiovascular and renal events. Direct inhibition of renin -the most proximal aspect of the RAS -became clinically feasible from 2007 with the introduction of aliskiren. This latter drug has been shown to be efficacious for the management of hypertension. Combined therapy of direct renin-inhibitors with ACEIs or ARBs has been tested in some clinical situations as congestive HF and proteinuria with diverse results. This article tries to offer an updated review of current knowledge on the use of RAS blocking drugs in clinical settings.

Pharmacological blood pressure lowering in the older hypertensive patients may lead to cognitive impairment by altering neurovascular coupling

The link between both high and low blood pressure (BP) levels and cognitive impairment in later life has been reported in several studies. The mechanisms for this link are unclear but may be related to abnormalities in brain blood flow control. Our previous work has shown that cerebral autoregulation (CA) is unimpaired in both young and older people with hypertension at rest and that ageing does not appear to impact on the increase in the cerebral blood flow response to increased metabolic demand of neurones and other cells of the nervous system due to heightened activity (Neurovascular Coupling, NVC). Nonetheless, it is plausible that NVC efficiency becomes compromised during mental activity in older people with hypertension and that certain classes of anti-hypertensive agents may exacerbate the situation by reducing both NVC and CA contributing to cognitive decline. Such a link would have a major impact on prescribing patterns for anti-hypertensive medication.

Telmisartan protects against cognitive decline via up-regulation of brain-derived neurotrophic factor/tropomyosin-related kinase B in hippocampus of hypertensive rats

BACKGROUND AND PURPOSE

Cognitive decline may occur as a result of hypertension, and is dependent on the function of hippocampus. Brain-derived neurotrophic factor (BDNF) mediated by angiotensin II-induced oxidative stress protects against cell death in hippocampus. Angiotensin II receptor blocker (ARB), candesartan, activates BDNF in the hippocampus. Furthermore, peroxisome proliferator-activated receptor (PPAR)-gamma activation in the brain prevents brain damage. Telmisartan, a unique ARB with PPAR-gamma stimulating activity, protects against cognitive decline partly because of PPAR-gamma activation. The aim of the present study was to determine whether telmisartan protects against cognitive decline via up-regulation of BDNF and its receptor tropomyosin-related kinase B (TrkB) in the hippocampus of hypertensive rats, partly because of PPAR-gamma activation.

METHODS AND RESULTS

We divided stroke-prone spontaneously hypertensive rats (SHRSPs), as hypertensive and vascular dementia model rats, into five groups, telmisartan-treated (TLM), TLM+GW9662, a PPAR-gamma inhibitor, -treated (T+G), GW9662-treated (GW), TLM+ANA-12, a TrkB antagonist, -treated (T+A), and vehicle-treated SHRSPs (VEH). After the treatment for 28 days, systolic blood pressure did not change in all groups. However, BDNF expression in the hippocampus was significantly higher in TLM than in VEH to a greater extent than in T+G. Cognitive performance was significantly higher in TLM than in VEH to a greater extent than in T+G, and was not different between T+A, GW, and VEH.

CONCLUSION

Telmisartan protects against cognitive decline via up-regulation of BDNF/TrkB in the hippocampus of SHRSPs, partly because of PPAR-gamma activation independent of blood pressure-lowering effect.

Blood pressure responses to hypertension treatment and trends in cognitive function in patients with initially difficult-to-treat hypertension: a retrospective subgroup analysis of the Observational Study on Cognitive Function and SBP Reduction (OSCAR) study

The Observational Study on Cognitive Function and SBP Reduction (OSCAR) provided opportunities to examine the influence of eprosartan on trends in cognitive performance in a large population of patients with difficult-to-treat hypertension (DTTH). A total of 4649 patients diagnosed retrospectively with DTTH, defined as systolic/diastolic blood pressure (SBP/DBP) ≥140/90 mm Hg despite use of at least 3 antihypertensive drugs during the month preceding the baseline visit comprised the intention-to-treat (ITT) cohort. The patients were given eprosartan-based antihypertension therapy (EBT; 600 mg/d). Blood pressure and cognitive function parameters included significant (P<.001) differences for DTTH vs non-DTTH patients such as older age, body mass index, SBP and pulse pressure (PP), and lower Mini-Mental State Examination (MMSE) score. After EBT for 6 months, SBP/DBP in DTTH was 138.8±12.2/81.9±7.4 (ΔSBP-26±15.7; ΔDBP-11.4±9.8); PP was 57.0±10.8 (ΔPP-14.5±13.8) (all P<.001 vs baseline and non-DTTH group). A total of 2576 patients (87.4%) responded to EBT (ie, SBP <140 mm Hg and/or ΔSBP ≥15 mm Hg, or DBP <90 mm Hg and/or ΔDBP ≥10 mm Hg); 1426 DTTH patients (48.4%) achieved normalized SBP/DBP (ie, SBP <140 mm Hg and DBP <90 mm Hg). ΔPP in DTTH-isolated systolic hypertension (ISH) was -18.0±13.3 mm Hg (P=.003 vs DTTH-systolic-diastolic hypertension). End-of-EBT mean MMSE was 27.5±3.0 (P<.001 vs baseline). Blood pressure responses after EBT coincided with stabilization/improvement of MMSE in this retrospective investigation in DTTH patients. The average improvement in MMSE in DTTH patients was similar to that in non-DTTH patients. EBT effects on PP may be relevant to the evolution of MMSE in DTTH-ISH patients.

Cognitive enhancement following acute losartan in normotensive young adults

RATIONALE

Losartan, an angiotensin II receptor antagonist (AIIA), is an antihypertensive that has previously been suggested to have cognitive-enhancing potential for older adults. The objective indices for such effects are equivocal, however, and if these drugs do offer dual advantages of hypertension control plus cognitive-enhancing potential, there exists a clear need to establish this directly.

OBJECTIVES

This work examines the potential of losartan administered as a single dose to healthy young adults to improve cognitive performance alone or to reverse scopolamine-induced cognitive decrements.

METHODS

In two placebo-controlled, double-blind studies, participants completed a cognitive test battery once before and once after drug absorption. In experiment 1, participants were randomly allocated to receive placebo, losartan 50 mg or losartan 100 mg. In experiment 2, participants were randomly allocated to one of four treatment groups: placebo/placebo, placebo/scopolamine, losartan/scopolamine and losartan/placebo (50 mg losartan p.o. and 1.2 mg scopolamine hydrochloride p.o.).

RESULTS

Losartan 50 mg improved performance on a task of prospective memory when administered alone and reversed the detrimental effects of scopolamine both in a standard lexical decision paradigm (p < 0.01) and when the task incorporated a prospective memory component (p < 0.008).

CONCLUSIONS

The findings highlight a cognitive-enhancing potential for losartan on compromised cognitive systems and emphasise the potential of AIIAs to produce benefits over and above hypertension control.

Blood pressure is associated with higher brain amyloid burden and lower glucose metabolism in healthy late middle-age persons

Epidemiological studies suggest that elevated blood pressure (BP) in midlife is associated with increased risk of Alzheimer's disease (AD) in late life. In this preliminary study, we investigated the extent to which BP measurements are related to positron emission tomography (PET) measurements of fibrillar amyloid-beta burden using Pittsburgh Compound-B (PiB) and fluorodeoxyglucose (FDG) PET measures of cerebral metabolic rate for glucose metabolism (CMRgl) in cognitively normal, late middle-aged to older adult apolipoprotein E (APOE) ε4 homozygotes, heterozygotes and noncarriers. PiB PET results revealed that systolic BP (SBP) and pulse pressure (PP) were each positively correlated with cerebral-to-cerebellar PiB distribution volume ratio (DVR) in frontal, temporal, and posterior-cingulate/precuneus regions, whereas no significant positive correlations were found between PiB distribution volume ratios and diastolic BP (DBP). FDG PET results revealed significant inverse correlations between each of the BP measures and lower glucose metabolism in frontal and temporal brain regions. These preliminary findings provide additional evidence that higher BP, likely a reflection of arterial stiffness, during late midlife may be associated with increased risk of presymptomatic AD.

Eprosartan-based hypertension therapy, systolic arterial blood pressure and cognitive function: analysis of Middle East data from the OSCAR study

Background:

Studies have indicated a relationship between hypertension and cognitive function. The possible effect of antihypertensive therapy on cognitive disorders is therefore a matter of interest.

Materials and methods:

The Observational Study on Cognitive function And SBP Reduction (OSCAR) was an open-label, multinational trial designed to evaluate the impact of eprosartan-based antihypertensive therapy on cognitive function in patients with essential hypertension. Eprosartan 600 mg/day for 6 months (with provision for additional medication as needed) was initiated in hypertensive subjects aged ≥50 years. A total of 853 patients in an intention-to-treat cohort from seven countries of the Middle East was identified for subgroup analysis.

Results:

Arterial blood pressure was reduced significantly (P < 0.001) during the study: At the end of 6 months of eprosartan-based therapy, the mean (±SD) reduction from baseline was 32.1 ± 14.3/14.6.3 ± 8.6 mmHg (P < 0.001). Mean pulse pressure was reduced by 18.3 ± 13.1 mmHg (P < 0.0001 vs baseline). Blood pressure was normalized (systolic <140 mmHg and diastolic <90 mmHg) in 68.2% of patients. The overall mean Mini-Mental State Examination (MMSE) score after 6 months of eprosartan-based therapy was one-point higher than at baseline (P < 0.001). MMSE score on completion of 6 months’ follow-up was either unchanged or increased from baseline in 793 (93%) individuals and decreased in 60 (7%). Factors associated with stability of or improvement in cognitive function included MMSE score at baseline, diastolic blood pressure (DBP) at baseline, and treatment-induced change in DBP.

Conclusion:

Results from the Middle East subgroup of OSCAR are supportive of the hypothesis that antihypertensive therapy based on angiotensin-receptor blocker therapy with eprosartan may be associated with preservation or improvement of cognitive function.

Non-adherence to antihypertensive medication and impaired cognition: which comes first?

OBJECTIVE

Antihypertensive medications are important in the prevention of serious consequences of hypertension, such as stroke and heart failure. Up to one-third of elderly hypertensive patients, however, do not adhere to their medication. Adherence to medication decreases with increasing age, and with decreasing cognitive ability, thus elderly, cognitively-impaired patients have poorer control of blood pressure. Good control of blood pressure is associated with decreased prevalence of dementia and Alzheimer's disease. This study assessed the evidence that antihypertensive medications have effects on the prevalence or severity of mild cognitive impairment, dementia or Alzheimer's disease.

METHODS

The ISI Web of Knowledge database was searched; including replicates, the nine searches identified 14400 publications since 1952, of which 9.9% had been published in 2009. This review considers the 18 studies meeting the set criteria published in 2009 or later.

KEY FINDINGS

Not all antihypertensive medications are equivalent in their positive cognitive effects, with brain-penetrating angiotensin-converting-enzyme inhibitors and possibly angiotensin receptor antagonists being the most effective.

CONCLUSIONS

Based on evidence of blood-pressure control and cost, UK National Institute for Health and Clinical Excellence guidelines recommend calcium-channel blockers or thiazide-type diuretics for the treatment of hypertension in patients over 55 years. These guidelines take no account of the potential cognitive effects of the antihypertensive therapies, consideration of which might lead to a review. There may be benefit in stressing that adherence to antihypertensive medication not only decreases the risk of cardiovascular disease and death, but may also decrease the risk or severity of mild cognitive impairment, dementia and Alzheimer's disease.

Eprosartan: a review of its use in hypertension

Eprosartan is an angiotensin II receptor antagonist (angiotensin II receptor blocker [ARB]) used in the treatment of hypertension. In large, randomized trials, eprosartan (with or without hydrochlorothiazide [HCTZ]) demonstrated superior antihypertensive efficacy to that of placebo and, when administered at comparable dosage regimens, had similar blood pressure-lowering effects to enalapril. Eprosartan was generally well tolerated in clinical trials and had a lower incidence of persistent dry cough than enalapril. Eprosartan has a neutral effect on metabolic parameters, such as serum lipid levels and glucose homeostasis, and a low propensity for pharmacokinetic drug interactions. The use of eprosartan or other ARBs in combination with HCTZ tends to reverse the potassium loss associated with thiazide diuretics. Independent of its antihypertensive effects, eprosartan was associated with improved clinical outcomes (primary composite endpoint of all causes of mortality and all cardiovascular and cerebrovascular events, including all recurrent events) compared with nitrendipine in a randomized, secondary prevention trial in hypertensive patients with previous cerebrovascular events (MOSES trial). Eprosartan also reduced blood pressure and was associated with a modest improvement in cognitive function in a large observational study in patients > or =50 years of age with newly diagnosed hypertension (OSCAR study). In both of these trials, additional antihypertensive therapy, such as HCTZ, was permitted. Therefore, eprosartan is a useful treatment option in the management of a broad range of patients with hypertension, and its use with HCTZ provides a rational combination regimen.

Hypertension and dementia

Although hypertension is well known as a cause of vascular dementia (VaD), recent findings highlight the role of hypertension in the pathogenesis of Alzheimer's disease (AD) as well as mild cognitive impairment (MCI). Recent studies have shown that disruption of diurnal blood pressure (BP) variation is closely associated with cognitive impairment via injury of the small cerebral arteries indicating that long-standing hypertension constitutes a risk of brain matter atrophy or white matter lesions (WMLs). In several clinical trials, BP-lowering with antihypertensive agents was suggested to reduce the risk of dementia or cognitive decline. This review paper focuses on the role of hypertension as a risk factor for cognitive impairment, and summarizes current knowledge on the relationships between ambulatory BP monitoring (ABPM) and cognitive impairment. Finally, an overview of the impact of antihypertensive therapy on dementia prevention is provided.

Use of angiotensin receptor blockers and risk of dementia in a predominantly male population: prospective cohort analysis

OBJECTIVE

To investigate whether angiotensin receptor blockers protect against Alzheimer's disease and dementia or reduce the progression of both diseases.

DESIGN

Prospective cohort analysis.

SETTING

Administrative database of the US Veteran Affairs, 2002-6. Population 819 491 predominantly male participants (98%) aged 65 or more with cardiovascular disease.

MAIN OUTCOME MEASURES

Time to incident Alzheimer's disease or dementia in three cohorts (angiotensin receptor blockers, lisinopril, and other cardiovascular drugs, the "cardiovascular comparator") over a four year period (fiscal years 2003-6) using Cox proportional hazard models with adjustments for age, diabetes, stroke, and cardiovascular disease. Disease progression was the time to admission to a nursing home or death among participants with pre-existing Alzheimer's disease or dementia.

RESULTS

Hazard rates for incident dementia in the angiotensin receptor blocker group were 0.76 (95% confidence interval 0.69 to 0.84) compared with the cardiovascular comparator and 0.81 (0.73 to 0.90) compared with the lisinopril group. Compared with the cardiovascular comparator, angiotensin receptor blockers in patients with pre-existing Alzheimer's disease were associated with a significantly lower risk of admission to a nursing home (0.51, 0.36 to 0.72) and death (0.83, 0.71 to 0.97). Angiotensin receptor blockers exhibited a dose-response as well as additive effects in combination with angiotensin converting enzyme inhibitors. This combination compared with angiotensin converting enzyme inhibitors alone was associated with a reduced risk of incident dementia (0.54, 0.51 to 0.57) and admission to a nursing home (0.33, 0.22 to 0.49). Minor differences were shown in mean systolic and diastolic blood pressures between the groups. Similar results were observed for Alzheimer's disease.

CONCLUSIONS

Angiotensin receptor blockers are associated with a significant reduction in the incidence and progression of Alzheimer's disease and dementia compared with angiotensin converting enzyme inhibitors or other cardiovascular drugs in a predominantly male population.