Prevention of dementia in randomised double-blind placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial

Health-Promoting Strategies for the Aging Brain

As the world's population ages and people live longer, the changes in the aging brain present substantial challenges to our health and society. With greater longevity come age-related diseases, many of which have direct and indirect influences on the health of the brain. Although there is some degree of predictable decline in brain functioning with aging, meaningful cognitive decline is not inevitable and is perhaps preventable. In this review, we present the case that the course of aging-related brain disease and dysfunction can be modified. We present the evidence for conditions and risk factors that may contribute to cognitive decline and dementia and for interventions that may mitigate their impact on cognitive functioning later in life, or even prevent them and their cognitive sequelae from developing. Although much work remains to be done to meet the challenges of the aging brain, strategies to promote its health have been demonstrated and offer much promise, which can only be realized if we mount a vigorous public health effort to implement these strategies.

Randomised controlled trial of a Calcium Channel or Angiotensin Converting Enzyme Inhibitor/Angiotensin Receptor Blocker Regime to Reduce Blood Pressure Variability following Ischaemic Stroke (CAARBS): a protocol for a feasibility study

INTRODUCTION

Raised blood pressure (BP) is common after stroke and is associated with a poor prognosis, yet trials of BP lowering in the immediate poststroke period have not demonstrated a benefit. One possible explanation for this may be that BP variability (BPV) rather than absolute levels predicts outcome, as BPV is increased after stroke and is associated with poor outcomes. Furthermore, there is evidence of distinct antihypertensive class effects on BPV despite similar BP-lowering effects. However, whether BPV in the immediate poststroke period is a therapeutic target has not been prospectively investigated.The objectives of this trial are to assess the feasibility and safety of recruiting patients following an acute ischaemic stroke or transient ischaemic attack (TIA) to an interventional randomised controlled trial comparing the effects of two different antihypertensive drug classes on BPV. Secondary exploratory objectives are to assess if different therapeutic strategies have diverse effects on levels of BPV and if this has an impact on outcomes.

METHODS

150 adult patients with first-ever ischaemic stroke or TIA who require antihypertensive therapy for secondary prevention will be recruited within 7 days of the event from stroke services across three sites. After baseline assessments they will be randomly assigned to treatment with a calcium channel blocker or ACE inhibitor/angiotensin receptor blocker-based regimen and followed up for a period of three months.

ETHICS AND DISSEMINATION

Ethical and regulatory approvals have been granted. Dissemination is planned via publication in peer-reviewed medical journals and presentation at relevant conferences.

TRIAL REGISTRATION NUMBER

ISRCTN10853487.

No clear relationship between antihypertensive class and cognitive function over 12 months in a cohort study of community-dwelling adults aged 80 and over

Background:

Hypertension is prevalent in older adults. Hypertension has also been associated with an increased risk of cognitive decline. However, evidence relating to the impact of antihypertensive use is mixed. Calcium-channel blockers (CCB) have been suggested as the most beneficial class of antihypertensive for protection of cognition in older adults, however, to date, there have been no cohort studies designed to examine this.

Methods:

Community-dwelling treated hypertensive adults aged 80 and over were recruited from general practice sites and followed for 1 year. Cognitive function was assessed at baseline and 12 months using the modified Mini-Mental State Exam (3MS). Regression was used to examine the association between 12-month exposure to antihypertensive class and change in cognitive function.

Results:

A total of 292 participants completed the study. Mean change in 3MS score was a rise of 0.53 [standard deviation (SD) 4.7] 3MS points in those taking CCBs (n = 135) compared with a drop of 0.09 (SD 5.1) in those without (n = 157) p = 0.28. There was no relationship between CCBs or between any antihypertensive class and change in cognitive function over 1 year. Additional analyses using a clinically meaningful fall of 5 or more 3MS points showed similar results.

Conclusion:

In a hypertensive community-dwelling older adult population treated with antihypertensives, there was no evidence that CCBs were protective of cognitive function over a 12-month exposure. If a protective effect is present, it may be small or require a longer treatment period. Larger longer studies are required for confirmation.

Effect Modification by Age on the Benefit or Harm of Antihypertensive Treatment for Elderly Hypertensives: A Systematic Review and Meta-analysis

BACKGROUND

The influence of age on balance of benefit vs. potential harm of blood pressure (BP)-lowering therapy for elderly hypertensives is unclear. We evaluated the modifying effects of age on BP lowering for various adverse outcomes in hypertensive patients older than 60 years without specified comorbidities.

METHODS

All relevant randomized controlled trials (RCTs) were systematically identified. Coronary heart disease, stroke, heart failure (HF), cardiovascular death, major adverse cardiovascular events (MACE), renal failure (RF), and all-cause death were assessed. Meta-regression analysis was used to explore the relationship between achieved systolic BP (SBP) and the risk of adverse events. Random-effects meta-analysis was used to pool the estimates.

RESULTS

Our study included 18 RCTs (n = 53,993). Meta-regression analysis showed a lower achieved SBP related with a lower risk of stroke and cardiovascular death, but an increased risk of RF. The regression slopes were comparable between populations stratifying by age 75 years. In subgroup analysis, the relative risks of a more aggressive BP lowering strategy were similar between patients aged older or less than 75 years for all outcomes except for RF (P for interaction = 0.02). Compared to treatment with final achieved SBP 140-150 mm Hg, a lower achieved SBP (<140 mm Hg) was significantly associated with decreased risk of stroke (relative risk = 0.68; 95% confidence interval = 0.55-0.85), HF (0.77; 0.60-0.99), cardiovascular death (0.68; 0.52-0.89), and MACE (0.83; 0.69-0.99).

CONCLUSIONS

To treat hypertension in the elderly, age had trivial effect modification on most outcomes, except for renal failure. Close monitoring of renal function may be warranted in the management of elderly hypertension.

Stroke in the elderly

Stroke remains the second leading cause of death in the world, and its prevalence is projected to rise in the United States and globally. The main driver for increased stroke prevalence is aging of the population; however, best evidenced-based strategies for stroke treatment and prevention are not always followed for older patients. Furthermore, considerable gaps in knowledge exist for stroke prevention and treatment in elderly and very elderly patients. In this chapter, we discuss various aspects of stroke care in the elderly, including the evidence that guides stroke prevention and treatment. We focus on the challenges in managing stroke in the very elderly including the paucity of data to guide management. The sections span the continuum of stroke care, from primary prevention to management of stroke complications. Finally, we highlight the most significant unanswered questions regarding stroke care in the elderly.

Nitrendipine and Dementia: Forgotten Positive Facts?

Nowadays, there are about 50 million people suffering from dementia worldwide. In 2030, it is expected that there will be 82 million people living with dementia and in 2050, their number should reach 152 million. This increase in the number of people with dementia results in significant social and economic problems. Therefore, researchers attempt to reduce risk factors causing the development of dementia such as high blood pressure. Epidemiological studies have shown that hypertension increases the risk of dementia at an older age. It can, therefore, be assumed that hypertension therapy will reduce the risk of dementia. However, previous clinical studies have shown that the efficacy of different antihypertensive drugs differs in this respect. The drug group that appears to be the most effective in these analyses is calcium channel blockers (CCBs). The most significant preventive efficacy in terms of protection against dementia has been demonstrated with nitrendipine. Its use is, therefore, particularly advantageous in elderly patients with systolic hypertension who are at high risk of dementia. The purpose of this study is to restore the discussion on the prevention of vascular dementia and Alzheimer’s dementia with nitrendipine in indicated hypertonic patients. The authors performed a literature search of available sources describing the issue of dementia, hypertension and its treatment with nitrendipine. In addition, they made a comparison and evaluation of relevant findings. The results of the detected research studies indicate that nitrendipine is able to reduce the incidence of dementia [Alzheimer’s disease (AD), vascular and mixed] by 55%. The treatment of 1,000 patients with nitrendipine for 5 years may prevent 20 cases of dementia. However, what has not yet been explained is the temporal link between hypertension and dementia due to the long-time intervals between hypertension and the development of dementia.

Research Progress in the Pathogenesis of Alzheimer's Disease

Objective:

Alzheimer's disease (AD) is a kind of chronic degenerative disease of the central nervous system, characteristics of cognitive dysfunction, and behavioral disability. The pathological changes include the formation of senile plaques-containing beta-amyloid (Aβ), neurofibrillary tangles (NFTs), loss of neurons, and synapses. So far, the pathogenesis of AD is still unclear. This study was aimed to review the major pathogenesis of AD-related to the published AD studies in recent 20 years.

Data Sources:

The author retrieved information from the PubMed database up to January 2018, using various search terms and their combinations, including AD, Aβ, NFTs, pathogenesis, and genetic mutation.

Study Selection:

The author included data from peer-reviewed journals printed in English and Chinese on pathophysiological factors in AD. He organized these informations to explain the possible pathogenesis in AD.

Results:

There are many amounts of data supporting the view that AD pathogenesis so far there mainly are Aβ toxicity, tau protein, gene mutation, synaptic damages, intermediate neurons and network abnormalities, changes in mitochondrial function, chemokines, etc., Its nosogenesis may be involved in multiple theories and involved in multiple molecular signaling pathways, including Aβ, tau protein, and synaptic anomaly; mutual relationship between the mechanisms urge jointly neuronal degeneration.

Conclusions:

This review highlights the research advances in the pathogenesis of AD. Future research has needed to fully disclose the association between multiple pathogenesis at the same time to interdict multiple signaling pathways, etc.

Advances in developing novel therapeutic strategies for Alzheimer's disease

Alzheimer's Disease (AD), the most prevalent neurodegenerative disease of aging, affects one in eight older Americans. Nearly all drug treatments tested for AD today have failed to show any efficacy. There is a great need for therapies to prevent and/or slow the progression of AD. The major challenge in AD drug development is lack of clarity about the mechanisms underlying AD pathogenesis and pathophysiology. Several studies support the notion that AD is a multifactorial disease. While there is abundant evidence that amyloid plays a role in AD pathogenesis, other mechanisms have been implicated in AD such as tangle formation and spread, dysregulated protein degradation pathways, neuroinflammation, and loss of support by neurotrophic factors. Therefore, current paradigms of AD drug design have been shifted from single target approach (primarily amyloid-centric) to developing drugs targeted at multiple disease aspects, and from treating AD at later stages of disease progression to focusing on preventive strategies at early stages of disease development. Here, we summarize current strategies and new trends of AD drug development, including pre-clinical and clinical trials that target different aspects of disease (mechanism-based versus non-mechanism based, e.g. symptomatic treatments, lifestyle modifications and risk factor management).

Vascular Contribution to Cognition in Stroke and Alzheimer's Disease

Vascular factors to cognitive impairment in degenerative on non-degenerative diseases have been reported, examined, and debated for several decades. The various definitions of cognitive impairment due to vascular origins will make these results diverse. During this review, we are going to report currently update information of vascular contributions to cognitive function, in clinical or neuroimaging findings. Risks factors and their managements also will be discussed and reported to have a comprehensive review.

Hypertension Management at Older Age: An Update

Hypertension is a risk factor for cardiovascular morbidity and mortality with increasing prevalence with age, whose treatment is associated with benefits over fatal and non-fatal cardiovascular events even later in life. However, there are persistent concerns on the short- and long-term weighted benefits of treating hypertension in the very old, particularly in those with specific clinical features. In fact, a broad range of clinical scenarios can be observed at older ages, spanning from the healthy to the frailest patient, and hypertension clinical trials have traditionally excluded the latter, thus preventing the unconditioned application to these patients of the same recommendations as in younger ages. Persistent issues regarding high blood pressure management in the very old adult are mainly related to treatment threshold and targets, which have been differently addressed by American and European guidelines. Herein, we will examine the challenges related to high blood pressure treatment in healthy and frail older and very old adults. We will discuss the evidence behind current recommendations. Finally, we will recapitulate the recommended treatment options for high blood pressure in these patients in the light of the most recent guidelines.

Antihypertension drugs in prevention of cognition disorder and dementia: focus on calcium channel blockers and diuretics

Arterial hypertension is associated with elevated risk of cognition decline and vascular dementia development, as the Alzheimer disease development. Therefore, antihypertension therapy might be of preventive value. The review is focused on literary data that witness on, despite controversial, evidence of cerebroprotective action of the range of antihypertension medications. Especially, dihydropyridine calcium antagonists, diuretics and some blockers of renin-angiotensin-aldosterone system. These act not only via blood pressure decrease, but due to additional specific neuroprotective mechanisms. This makes it to consider calcium antagonists and diuretics as a major component of systemic hypertension management, incl. elderly and senile patients, aiming to prevent cognition decline and dementia of various types development.

Nitrendipine, among the calcium channels antagonists, and indapamide among diuretics have acquired the broadest evidence that points on their cerebroprotective properties.

Preoperative smoking history is associated with decreased risk of early postoperative cognitive dysfunction in patients of advanced age after noncardiac surgery: a prospective observational cohort study

Objective

Prevention of postoperative cognitive dysfunction (POCD) in patients of advanced age remains unclear. Studies have shown that the cholinergic anti-inflammatory pathway contributes to a decreased risk of POCD and that nicotine stimulates the cholinergic anti-inflammatory pathway. We investigated whether patients of advanced age with a preoperative smoking history have a decreased risk of POCD.

Methods

In total, 382 patients (190 smokers, 192 nonsmokers) aged ≥60 years who underwent major noncardiac surgery were enrolled. Cognitive function was assessed, and multivariate logistic regression analyses were performed to identify risk factors.

Results

On postoperative days 5 and 7, 111 (29.05%) and 90 (23.56%) patients exhibited POCD, respectively. A preoperative smoking history was significantly correlated with a decreased risk of POCD. A high serum tumor necrosis factor-α (TNF-α) level on the operative day was significantly associated with an increased risk of POCD. Early POCD was significantly associated with the sufentanil dosage, age, and education level. The hospital stay in patients with and without POCD was 10.54 ± 2.03 and 8.33 ± 1.58 days, respectively.

Conclusion

A preoperative smoking history was associated with a decreased risk of early POCD, and a high serum TNF-α level was significantly associated with an increased risk of POCD.

Nilvadipine in mild to moderate Alzheimer disease: A randomised controlled trial

BACKGROUND

This study reports the findings of the first large-scale Phase III investigator-driven clinical trial to slow the rate of cognitive decline in Alzheimer disease with a dihydropyridine (DHP) calcium channel blocker, nilvadipine. Nilvadipine, licensed to treat hypertension, reduces amyloid production, increases regional cerebral blood flow, and has demonstrated anti-inflammatory and anti-tau activity in preclinical studies, properties that could have disease-modifying effects for Alzheimer disease. We aimed to determine if nilvadipine was effective in slowing cognitive decline in subjects with mild to moderate Alzheimer disease.

METHODS AND FINDINGS

NILVAD was an 18-month, randomised, placebo-controlled, double-blind trial that randomised participants between 15 May 2013 and 13 April 2015. The study was conducted at 23 academic centres in nine European countries. Of 577 participants screened, 511 were eligible and were randomised (258 to placebo, 253 to nilvadipine). Participants took a trial treatment capsule once a day after breakfast for 78 weeks. Participants were aged >50 years, meeting National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's disease Criteria (NINCDS-ADRDA) for diagnosis of probable Alzheimer disease, with a Standardised Mini-Mental State Examination (SMMSE) score of ≥12 and <27. Participants were randomly assigned to 8 mg sustained-release nilvadipine or matched placebo. The a priori defined primary outcome was progression on the Alzheimer's Disease Assessment Scale Cognitive Subscale-12 (ADAS-Cog 12) in the modified intention-to-treat (mITT) population (n = 498), with the Clinical Dementia Rating Scale sum of boxes (CDR-sb) as a gated co-primary outcome, eligible to be promoted to primary end point conditional on a significant effect on the ADAS-Cog 12. The analysis set had a mean age of 73 years and was 62% female. Baseline demographic and Alzheimer disease-specific characteristics were similar between treatment groups, with reported mean of 1.7 years since diagnosis and mean SMMSE of 20.4. The prespecified primary analyses failed to show any treatment benefit for nilvadipine on the co-primary outcome (p = 0.465). Decline from baseline in ADAS-Cog 12 on placebo was 0.79 (95% CI, -0.07-1.64) at 13 weeks, 6.41 (5.33-7.49) at 52 weeks, and 9.63 (8.33-10.93) at 78 weeks and on nilvadipine was 0.88 (0.02-1.74) at 13 weeks, 5.75 (4.66-6.85) at 52 weeks, and 9.41 (8.09-10.73) at 78 weeks. Exploratory analyses of the planned secondary outcomes showed no substantial effects, including on the CDR-sb or the Disability Assessment for Dementia. Nilvadipine appeared to be safe and well tolerated. Mortality was similar between groups (3 on nilvadipine, 4 on placebo); higher counts of adverse events (AEs) on nilvadipine (1,129 versus 1,030), and serious adverse events (SAEs; 146 versus 101), were observed. There were 14 withdrawals because of AEs. Major limitations of this study were that subjects had established dementia and the likelihood that non-Alzheimer subjects were included because of the lack of biomarker confirmation of the presence of brain amyloid.

CONCLUSIONS

The results do not suggest benefit of nilvadipine as a treatment in a population spanning mild to moderate Alzheimer disease.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02017340, EudraCT number 2012-002764-27.

Progression of Alzheimer's disease, tau propagation, and its modifiable risk factors

The number of patients with Alzheimer's disease (AD) has been increasing exponentially side by side with aging societies worldwide. Symptoms of AD worsen over time due to progressive neurodegeneration, requiring institutional care at the later stage and resulting in a heavy burden on patients, caregivers, and the public-health system. AD neuropathology is characterized by cerebral accumulation and aggregation of amyloid-β (Aβ) and tau proteins. For decades, Aβ has been a leading target in the therapeutic development for AD, and many drug candidates have been tested in clinical trials; however, most medications have failed to slow the progression of the disease. Tau pathology currently is attracting more attention as an alternate target for developing disease-modifying therapy. Tau is known to spread in a hierarchical pattern in AD brain, likely by trans-synaptic tau transfer between neurons. Extracellular tau may mediate tau spreading and serve as biomarker for AD. AD pathogenesis is multifactorial, and many genetic- and non-genetic factors are known to contribute to Aβ- and tau-related pathology. Recent studies indicate an association between vascular risk factors and AD. Identifying modifiable risk factors for AD and understanding their contributory mechanisms could be key in tackling this devastating disease.

Management of hypertension in older people

INTRODUCTION

As the population ages, the prevalence of hypertension is increasing. Treatment of hypertension is associated with a reduction in cardiovascular risk. However, the optimal blood pressure targets in older people are not clearly defined due to paucity of randomised clinical trials specific to this age group.

AREAS COVERED

We performed a Medline and Embase search from 1998 to present for articles on the management of hypertension in older people published in English language.

EXPERT COMMENTARY

The recent guidelines have suggested a lower blood pressure target of less than 130/80 mmHg. Due to the heterogeneity of older people, this universal low target may not be applicable to all of them. Targets based on functional level rather than chronological age are more appropriate. Special considerations in older people such as increased prevalence of frailty, falls, dementia, polypharmacy and the predominance of isolated systolic hypertension should also be taken into account. Tighter control, if well tolerated, is suitable for the fit person but relaxed targets are more reasonable in individuals with physical or cognitive decline. Therefore, in older people, targets should be individualised putting quality, rather than quantity, of life at the heart of their care plans.

Circadian Rhythm and Alzheimer's Disease

Alzheimer’s disease (AD) is a neurodegenerative disorder with a growing epidemiological importance characterized by significant disease burden. Sleep-related pathological symptomatology often accompanies AD. The etiology and pathogenesis of disrupted circadian rhythm and AD share common factors, which also opens the perspective of viewing them as a mutually dependent process. This article focuses on the bi-directional relationship between these processes, discussing the pathophysiological links and clinical aspects. Common mechanisms linking both processes include neuroinflammation, neurodegeneration, and circadian rhythm desynchronization. Timely recognition of sleep-specific symptoms as components of AD could lead to an earlier and correct diagnosis with an opportunity of offering treatments at an earlier stage. Likewise, proper sleep hygiene and related treatments ought to be one of the priorities in the management of the patient population affected by AD. This narrative review brings a comprehensive approach to clearly demonstrate the underlying complexities linking AD and circadian rhythm disruption. Most clinical data are based on interventions including melatonin, but larger-scale research is still scarce. Following a pathophysiological reasoning backed by evidence gained from AD models, novel anti-inflammatory treatments and those targeting metabolic alterations in AD might prove useful for normalizing a disrupted circadian rhythm. By restoring it, benefits would be conferred for immunological, metabolic, and behavioral function in an affected individual. On the other hand, a balanced circadian rhythm should provide greater resilience to AD pathogenesis.

Perspectives on the relation of blood pressure and cognition in the elderly

The relationship of blood pressure to cognition in the elderly is a poorly understood topic. Many questions exist such as does treatment of hypertension prevent cognitive decline, the optimal timing of intervention and selecting the appropriate agent. In this review we will explore recent epidemiologic data and clinical trials addressing hypertension and cognition, review pathophysiology of chronic hypertension and effects of brain function, discuss the timing of intervention and finally review opportunities for future research.

Investigation of elastic features of aorta and color M-mode flow propagation velocity (APV) of descending aorta in the patients with ischemic and non-ischemic dilated cardiomyopathy

Aortic flow propagation velocity (APV) is a novel echocardiographic parameter used in coronary artery disease. It has also been used for the evaluation of aortic stiffness. In the present study, APV was measured in patients with ischemic and non-ischemic dilated cardiomyopathy (DCM) and was compared with the parameters of aortic stiffness such as aortic distensibility (AD) and aortic strain (AS). A total of 140 patients who had undergone coronary angiographic imaging were included in the study. Out of these patients, 44 had ischemic DCM, 46 had non-ischemic DCM, and 50 had normal coronary angiography (control group). AS, AD, and APV were calculated echocardiographically. One-way analysis of variance (ANOVA) and the Kruskal-Wallis test were used to compare continuous variables between the groups, while the categorical variables were compared using Pearson's Chi square test. Pearson's correlation test was used to investigate the parameters associated with APV, AS, and AD. Ischemic DCM and non-ischemic DCM groups differed significantly. The comparison of these groups with the control group, in terms of AS, AD, and APV values (ANOVA p < 0.001 for all) also showed a significant difference. APV was found to be significantly correlated with AS (r = 0.645, p < 0.001) and AD (r = 0.604, p < 0.001). In ROC analysis, the area under the curve (AUC) value for APV was 0.999 (p = 0.000) for detection of patients ischemic DCM and non-ischemic DCM. APV may be considered to be a novel and a simple echocardiographic marker, for both, distinguishing ischemic from non-ischemic DCM as well as for the presence of dilated cardiomyopathy with or without critical coronary artery disease.

The depressor axis of the renin–angiotensin system and brain disorders: a translational approach

All the components of the classic renin–angiotensin system (RAS) have been identified in the brain. Today, the RAS is considered to be composed mainly of two axes: the pressor axis, represented by angiotensin (Ang) II/angiotensin-converting enzyme/AT1 receptors, and the depressor and protective one, represented by Ang-(1–7)/ angiotensin-converting enzyme 2/Mas receptors. Although the RAS exerts a pivotal role on electrolyte homeostasis and blood pressure regulation, their components are also implicated in higher brain functions, including cognition, memory, anxiety and depression, and several neurological disorders. Overactivity of the pressor axis of the RAS has been implicated in stroke and several brain disorders, such as cognitive impairment, dementia, and Alzheimer or Parkinson’s disease. The present review is focused on the role of the protective axis of the RAS in brain disorders beyond its effects on blood pressure regulation. Furthermore, the use of drugs targeting centrally RAS and its beneficial effects on brain disorders are also discussed.

The role of clinic blood pressure for the diagnosis of hypertension

PURPOSE OF REVIEW

Recent data from randomized clinical trials and updates to hypertension guidelines warrant a review of the literature for the diagnosis and management of hypertension in the clinic setting. Although there have been significant advances in ambulatory blood pressure (BP) monitoring and home BP monitoring, office BP (OBP) measurements remains the primary means of diagnosis and treatment.

RECENT FINDINGS

The current review focuses on updated guidelines, proper technique, device selection, and the recent controversy regarding unattended BP measurements. We review the data on cardiovascular outcomes, the comparison of OBP with ambulatory BP monitoring and home BP monitoring and some of the pitfalls of OBP measurements.

SUMMARY

The current review highlights the need for constant review of BP goals to minimize cardiovascular risk and some of the ongoing controversies regarding OBP measurements.

Clinical Trials of Blood Pressure Lowering and Antihypertensive Medication: Is Cognitive Measurement State-of-the-Art?

Randomized controlled trials of blood pressure (BP) lowering and antihypertensive medication use on cognitive outcomes have often been disappointing, reporting mixed findings and small effect sizes. We evaluate the extent to which cognitive assessment protocols used in these trials approach state-of-the-art. Overall, we find that a primary focus on cognition and the systematic selection of cognitive outcomes across trials take a backseat to other trial goals. Twelve trials investigating change in cognitive functioning were examined and none met criteria for state-of-the-art assessment, including use of at least 4 tests indexing 2 cognitive domains. Four trials investigating incident dementia were also examined. Each trial used state-of-the-art diagnostic criteria to assess dementia, although follow-up periods were relatively short, with only 2 trials lasting for at least 3 years. Weaknesses in each trial may act to obscure or weaken the positive effects of BP lowering on cognitive functioning. Improving trial designs in terms of cognitive outcomes selected and length of follow-up periods employed could lead to more promising findings. We offer logical steps to achieve state-of-the-art assessment protocols, with examples, in hopes of improving future trials.

Visit-to-Visit Blood Pressure Variability and Alzheimer's Disease: Links and Risks

While hypertension has been shown to be a risk factor for vascular dementia, several studies have also demonstrated that hypertension also increases the risk of Alzheimer's disease (AD). Although the relationship between visit-to-visit blood pressure variability (VVV) and cognitive impairment, including AD, have been provided, the mechanisms remain poorly understood. This review paper focuses on the relationship of VVV with AD and summarizes the pathophysiology underlying that relationship, which appears to be mediated by arterial stiffness.

Antihypertensive Medication Regimen Intensity and Incident Dementia in an Older Population

OBJECTIVE

To investigate the association between antihypertensive medication regimen intensity and risk of incident dementia in an older population.

DESIGN

Prospective, longitudinal cohort study.

PARTICIPANTS/SETTING

A total of 1208 participants aged ≥78 years, free of dementia, and residing in central Stockholm at baseline (2001-2004).

MEASUREMENTS

Participants were examined at 3- and 6-year follow-up to detect incident dementia. Data were collected through face-to-face interviews, clinical examinations, and laboratory tests. Data on antihypertensive use were obtained by a physician through patient self-report, visual inspection, or medical records. Cox proportional hazards models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between time-varying antihypertensive regimen intensity and incident dementia after adjusting for potential confounders.

RESULTS

During the follow-up period, 125 participants were diagnosed with dementia. Participants who developed dementia were more likely to have vascular disease at baseline (66.4% vs 55.3%, P = .02). In fully adjusted analyses, the number of antihypertensive classes (HR 0.68, 95% CI 0.55-0.84) and total prescribed daily dose (HR 0.70, 95% CI 0.57-0.86) were significantly associated with reduced dementia risk. After considering all-cause mortality as a competing risk, the number (HR 0.75, 95% CI 0.62-0.91) and doses (HR 0.71, 95% CI 0.59-0.86) of antihypertensive classes, and the independent use of diuretics (HR 0.66, 95% CI 0.44-0.99), were significantly associated with lower dementia risk.

CONCLUSIONS

Greater intensity of antihypertensive drug use among older people may be associated with reduced incidence of dementia.

Risk factors for dementia

There is little doubt that dementia is a very common cause of disability and dependency in our society. Since dementia of whatever type is usually more common with increasing age, then as population demographics change, so will the prevalence of dementia. Dementia is a generic term and the objective for clinicians, once dementia is suspected, is to attempt to define the cause. Alzheimer's disease is the most common cause of dementia, and in most centres vascular dementia would feature as the next most common aetiology. In some centres, Lewy body dementia is the second most common cause. Mixed Alzheimer's disease and vascular dementia would also feature high on the list at most centres.

Blood pressure from mid- to late life and risk of incident dementia

OBJECTIVE

To determine the association between blood pressure during midlife (40-64 years) to late life (≥65 years) and risk of incident dementia.

METHODS

This study included 1,440 (758 women, mean age 69 ± 6 years) Framingham Offspring participants who were free of dementia and attended 5 consecutive examinations at 4-year intervals starting at midlife (1983-1987, mean age 55 years) until late life (1998-2001, mean 69 years) and subsequently were followed up for incident dementia (mean 8 years). We determined the effect of midlife hypertension (≥140/90 mm Hg), late life hypertension, lower late life blood pressure (<100/70 mm Hg), persistence of hypertension during mid- to late life, and steep decline in blood pressure from mid- to late life over an 18-year exposure period.

RESULTS

During the follow-up period, 107 participants (71 women) developed dementia. Using multivariable Cox proportional hazards models, we found that midlife systolic hypertension (hazard ratio [HR] 1.57, 95% confidence interval [CI] 1.05-2.35) and persistence of systolic hypertension into late life (HR 1.96, 95% CI 1.25-3.09) were associated with an elevated risk of incident dementia. However, in individuals with low to normal blood pressure (≤140/90 mm Hg) at midlife, a steep decline in systolic blood pressure during mid- to late life was also associated with a >2-fold increase in dementia risk (HR 2.40, 95% CI 1.39-4.15).

CONCLUSIONS

Elevated blood pressure during midlife, persistence of elevated blood pressure into late life, and, among nonhypertensives, a steep decline in blood pressure during mid- to late life were associated with an increased dementia risk in a community-based cohort. Our data highlight the potential sustained cognitive benefits of lower blood pressures in midlife but also suggest that declining blood pressure in older adults with prehypertension or normotension, but not in those with hypertension, may be a risk marker for dementia.

Early Cognitive Impairment after Intracerebral Hemorrhage in the INTERACT1 Study

Background: Data on cognitive impairment after acute intracerebral hemorrhage (ICH) are limited. This study is aimed at determining the frequency and predictors of cognitive impairment among participants of the pilot phase, Intensive Blood Pressure (BP) Reduction in Acute Cerebral Hemorrhage Trial (INTERACT1). Methods: INTERACT1 was an open randomized trial of early intensive (target systolic BP <140 mm Hg) compared with contemporaneous guideline-recommended BP lowering in 404 patients with elevated systolic BP (150–220 mm Hg) within 6 h of ICH onset. Cognitive impairment was defined by scores ≤24 on the Mini-Mental State Examination (MMSE) assessed by interview on follow-up at 90 days. Results: A total of 231 (64.5%) of 358 90-day survivors had MMSE scores for analyses, and 75 (32.5%) had cognitive impairment. In multivariable analysis, older age (OR 2.48, 95% CI 1.73–3.56 per 10-year increase; p < 0.001), female sex (OR 2.06, 95% CI 1.00–4.23; p = 0.049), prior ICH (OR 2.87, 95% CI 1.08–7.65; p = 0.035), high baseline National Institute of Health Stroke Scale score (OR 1.06, 95% CI 1.00–1.13; p = 0.044), and high mean systolic BP over the first 24 h post-randomization (OR 1.34, 95% CI 1.07–1.68/10 mm Hg increase; p = 0.011) were independently associated with cognitive impairment. Conclusions: One third of patients have significant cognitive impairment early after ICH, which is more frequent in the elderly, females, those with prior ICH, and more severe initial neurological deficit and with persistently high early systolic BP.

Is Vascular Amyloidosis Intertwined with Arterial Aging, Hypertension and Atherosclerosis?

Vascular amyloidosis (VA) is a component of aging, but both VA and aging move forward together. Although, not all age-related molecules are involved with VA, some molecules are involved in a crosstalk between both of them. However, the cellular mechanism by which, vascular cells are phenotypically shifted to arterial remodeling, is not only involved in aging but also linked to VA. Additionally, patients with hypertension and atherosclerosis are susceptible to VA, while amyloidosis alone may provide fertile soil for the initiation and progression of subsequent hypertension and atherosclerosis. It is known that hypertension, atherosclerosis and amyloidosis can be viewed as accelerated aging. This review summarizes the available experimental and clinical evidence to help the reader to understand the advance and underlying mechanisms for VA involvement in and interaction with aging. Taken together, it is clear that VA, hypertension and atherosclerosis are closely intertwined with arterial aging as equal partners.

Defining Optimal Brain Health in Adults: A Presidential Advisory From the American Heart Association/American Stroke Association

Cognitive function is an important component of aging and predicts quality of life, functional independence, and risk of institutionalization. Advances in our understanding of the role of cardiovascular risks have shown them to be closely associated with cognitive impairment and dementia. Because many cardiovascular risks are modifiable, it may be possible to maintain brain health and to prevent dementia in later life. The purpose of this American Heart Association (AHA)/American Stroke Association presidential advisory is to provide an initial definition of optimal brain health in adults and guidance on how to maintain brain health. We identify metrics to define optimal brain health in adults based on inclusion of factors that could be measured, monitored, and modified. From these practical considerations, we identified 7 metrics to define optimal brain health in adults that originated from AHA's Life's Simple 7: 4 ideal health behaviors (nonsmoking, physical activity at goal levels, healthy diet consistent with current guideline levels, and body mass index <25 kg/m2) and 3 ideal health factors (untreated blood pressure <120/<80 mm Hg, untreated total cholesterol <200 mg/dL, and fasting blood glucose <100 mg/dL). In addition, in relation to maintenance of cognitive health, we recommend following previously published guidance from the AHA/American Stroke Association, Institute of Medicine, and Alzheimer's Association that incorporates control of cardiovascular risks and suggest social engagement and other related strategies. We define optimal brain health but recognize that the truly ideal circumstance may be uncommon because there is a continuum of brain health as demonstrated by AHA's Life's Simple 7. Therefore, there is opportunity to improve brain health through primordial prevention and other interventions. Furthermore, although cardiovascular risks align well with brain health, we acknowledge that other factors differing from those related to cardiovascular health may drive cognitive health. Defining optimal brain health in adults and its maintenance is consistent with the AHA's Strategic Impact Goal to improve cardiovascular health of all Americans by 20% and to reduce deaths resulting from cardiovascular disease and stroke by 20% by the year 2020. This work in defining optimal brain health in adults serves to provide the AHA/American Stroke Association with a foundation for a new strategic direction going forward in cardiovascular health promotion and disease prevention.

Impact of hypertension severity on arterial stiffness, cerebral vasoreactivity, and cognitive performance

Aging, hypertension (HTN), and other cardiovascular risk factors contribute to structural and functional changes of the arterial wall.

OBJECTIVE

To evaluate whether arterial stiffness (AS) is related to cerebral blood flow changes and its association with cognitive function in patients with hypertension.

METHODS

211 patients (69 normotensive and 142 hypertensive) were included. Patients with hypertension were divided into 2 stages: HTN stage-1 and HTN stage-2. The mini-mental state examination (MMSE), Montreal Cognitive Assessment (MoCA) and a battery of neuropsychological (NPE) tests were used to determine cognitive function. Pulse wave velocity was measured using the Complior®. Carotid properties were assessed by radiofrequency ultrasound. Central arterial pressure and augmentation index were obtained using applanation tonometry. Middle cerebral artery flow velocity was measured by transcranial Doppler ultrasonography.

RESULTS

Both arterial stiffness parameters and cerebral vasoreactivity worsened in line with HTN severity. There was a negative correlation between breath holding index (BHI) and arterial stiffness parameters. Cognitive performance worsened in line with HTN severity, with statistical difference occurring mainly between the HTN-2 and normotension groups on both the MMSE and MoCA. The same tendency was observed on the NPE tests.

CONCLUSION

Hypertension severity was associated with higher AS, worse BHI, and lower cognitive performance.

The renin angiotensin system and the brain: New developments

The traditional renin-angiotensin system (RAS) is indispensable system in adjusting sodium homeostasis, body fluid volume, and controlling arterial blood pressure. The key elements are renin splitting inactive angiotensinogen to yield angiotensin (Ang-I). Ang-1 is then changed by angiotensin-1 converting enzyme (ACE) into angiotensin II (Ang-II). Using PubMed, Google Scholar, and other means, we searched the peer-reviewed literature from 1990 to 2013 for articles on newly discovered findings related to the RAS, especially focusing on how the system influences the central nervous system (CNS). The classical RAS is now considered to be only part of the picture; the discovery of additional RAS pathways in the brain and elsewhere has yielded a vastly improved understanding of how the RAS influences the CNS. Newly discovered effects of the RAS on brain tissue include neuroprotection, cognition, and cerebral vasodilation. A number of brain biochemical pathways are influenced by the brain RAS. Within various pathways, there are potential opportunities for classical pharmacologic interventions as well as the possibility of controlling gene expression.

Dementia risk and prevention by targeting modifiable vascular risk factors

The incidence of dementia is expected to double in the next 20 years and will contribute to heavy social and economic burden. Dementia is caused by neuronal loss that leads to brain atrophy years before symptoms manifest. Currently, no cure exists and extensive efforts are being made to mitigate cognitive impairment in late life in order to reduce the burden on patients, caregivers, and society. The most common type of dementia, Alzheimer's disease (AD), and vascular dementia (VaD) often co-exists in the brain and shares common, modifiable risk factors, which are targeted in numerous secondary prevention trials. There is a growing need for non-pharmacological interventions and infrastructural support from governments to encourage psychosocial and behavioral interventions. Secondary prevention trials need to be redesigned based on the risk profile of individual subjects, which require the use of validated and standardized clinical, biological, and neuroimaging biomarkers. Multi-domain approaches have been proposed in high-risk populations that target optimal treatment; clinical trials need to recruit individuals at the highest risk of dementia before symptoms develop, thereby identifying an enriched disease group to test preventative and disease modifying strategies. The underlying aim should be to reduce microscopic brain tissue loss by modifying vascular and lifestyle risk factors over a relatively short period of time, thus optimizing the opportunity for preventing dementia in the future. Collaboration between international research groups is of key importance to the optimal use and allocation of existing resources, and the development of new techniques in preventing dementia. This article is part of the Special Issue "Vascular Dementia".

Relationship Between Antihypertensive Medications and Cognitive Impairment: Part I. Review of Human Studies and Clinical Trials

Purpose of review

There is an established association between hypertension and increased risk of poor cognitive performance and dementia including Alzheimer’s disease; however, associations between antihypertensive medications (AHMs) and dementia risk are less consistent. An increased interest in AHM has resulted in expanding publications; however, none of the recent reviews are comprehensive. Our extensive review includes 15 observational and randomized controlled trials (RCTs) published over the last 5 years, assessing the relationship between AHM and cognitive impairment.

Recent findings

All classes of AHM showed similar result patterns in human studies with the majority of study results reporting point estimates below one and only a small number of studies (N = 15) reporting statistically significant results in favor of a specific class.

Summary

Only a small number of studies reported statistically significant results in favor of a specific class of AHM. Methodological limitations of the studies prevent definitive conclusions. Further work is now needed to evaluate the class of AHM and cognitive outcomes in future RCTs, with a particular focus on the drugs with the promising results in both animals and human observational studies.

Electronic supplementary material

The online version of this article (doi:10.1007/s11906-016-0674-1) contains supplementary material, which is available to authorized users.

Relationship Between Antihypertensive Medications and Cognitive Impairment: Part II. Review of Physiology and Animal Studies

PURPOSE OF REVIEW

There is an established association between hypertension and increased risk of poor cognitive performance and dementia including Alzheimer's disease; however, associations between antihypertensive medications (AHM) and dementia risk are less clear. An increased interest in AHM has resulted in expanding publications; however, none of the recent reviews provide comprehensive review. Our extensive review includes 24 mechanistic animal and human studies published over the last 5 years assessing relationship between AHM and cognitive function.

RECENT FINDINGS

All classes of AHM showed similar result patterns in animal studies. The mechanism by which AHM exert their effect was extensively studied by evaluating well-established pathways of AD disease process, including amyloid beta (Aβ), vascular, oxidative stress and inflammation pathways, but only few studies evaluated the blood pressure lowering effect on the AD disease process. Methodological limitations of the studies prevent comprehensive conclusions prior to further work evaluating AHM in animals and larger human observational studies, and selecting those with promising results for future RCTs.