Effects of long-term blood pressure lowering and dual antiplatelet treatment on cognitive function in patients with recent lacunar stroke: a secondary analysis from the SPS3 randomised trial

Association of peripheral immunity and cerebral small vessel disease in older adults without dementia: A longitudinal study

This study explored the associations between peripheral immunity with cerebral small vessel diseases. Older adults without dementia from the Alzheimer's Disease Neuroimaging Initiative were investigated. Peripheral blood was obtained, and magnetic resonance imaging was performed to measure cerebral microbleeds (CMB), lacunar infarctions (LI), and white matter hyperintensities (WMH). Multivariable-adjusted regression models, linear mixed-effects models, and the Spearman correlations were used to evaluate the associations. At baseline, individuals with greater neutrophils (odds ratio [OR] =1.10, 95% confidence interval [CI] 1.00-1.20, p=0.042) and monocytes (OR=1.12, 95% CI 1.02-1.22, p=0.016) had higher WMH volume. On the contrary, a higher lymphocyte-to-monocyte ratio (LMR) was related to lower WMH volume (OR=0.91, 95% CI 0.82-1.00, p=0.041). Longitudinally, higher neutrophils (ρ=0.084, p=0.049) and NLR (ρ=0.111, p=0.009) predicted accelerated progression of WMH volume, while a greater LMR (ρ=-0.101, p=0.018) was linked to slower growth of WMH volume. Nevertheless, associations between peripheral immunity with CMB or LI were not observed at baseline and follow-up. Our study found that peripheral immune indexes could serve as convenient noninvasive biomarkers of WMH.

Design of trials in lacunar stroke and cerebral small vessel disease: review and experience with the LACunar Intervention Trial 2 (LACI-2)

Cerebral small vessel disease (cSVD) causes lacunar stroke (25% of ischaemic strokes), haemorrhage, dementia, physical frailty, or is 'covert', but has no specific treatment. Uncertainties about the design of clinical trials in cSVD, which patients to include or outcomes to assess, may have delayed progress. Based on experience in recent cSVD trials, we reviewed ways to facilitate future trials in patients with cSVD.We assessed the literature and the LACunar Intervention Trial 2 (LACI-2) for data to inform choice of Participant, Intervention, Comparator, Outcome, including clinical versus intermediary endpoints, potential interventions, effect of outcome on missing data, methods to aid retention and reduce data loss. We modelled risk of missing outcomes by baseline prognostic variables in LACI-2 using binary logistic regression.Imaging versus clinical outcomes led to larger proportions of missing data. We present reasons for and against broad versus narrow entry criteria. We identified numerous repurposable drugs with relevant modes of action to test in various cSVD subtypes. Cognitive impairment is the most common clinical outcome after lacunar ischaemic stroke but was missing more frequently than dependency, quality of life or vascular events in LACI-2. Assessing cognitive status using Diagnostic and Statistical Manual for Mental Disorders Fifth Edition can use cognitive data from multiple sources and may help reduce data losses.Trials in patients with all cSVD subtypes are urgently needed and should use broad entry criteria and clinical outcomes and focus on ways to maximise collection of cognitive outcomes to avoid missing data.

European stroke organisation (ESO) guideline on cerebral small vessel disease, part 2, lacunar ischaemic stroke

A quarter of ischaemic strokes are lacunar subtype, typically neurologically mild, usually resulting from intrinsic cerebral small vessel pathology, with risk factor profiles and outcome rates differing from other stroke subtypes. This European Stroke Organisation (ESO) guideline provides evidence-based recommendations to assist with clinical decisions about management of lacunar ischaemic stroke to prevent adverse clinical outcomes. The guideline was developed according to ESO standard operating procedures and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. We addressed acute treatment (including progressive lacunar stroke) and secondary prevention in lacunar ischaemic stroke, and prioritised the interventions of thrombolysis, antiplatelet drugs, blood pressure lowering, lipid lowering, lifestyle, and other interventions and their potential effects on the clinical outcomes recurrent stroke, dependency, major adverse cardiovascular events, death, cognitive decline, mobility, gait, or mood disorders. We systematically reviewed the literature, assessed the evidence and where feasible formulated evidence-based recommendations, and expert concensus statements. We found little direct evidence, mostly of low quality. We recommend that patients with suspected acute lacunar ischaemic stroke receive intravenous alteplase, antiplatelet drugs and avoid blood pressure lowering according to current acute ischaemic stroke guidelines. For secondary prevention, we recommend single antiplatelet treatment long-term, blood pressure control, and lipid lowering according to current guidelines. We recommend smoking cessation, regular exercise, other healthy lifestyle modifications, and avoid obesity for general health benefits. We cannot make any recommendation concerning progressive stroke or other drugs. Large randomised controlled trials with clinically important endpoints, including cognitive endpoints, are a priority for lacunar ischaemic stroke.

Advances in Cerebral Small Vessel Disease: Sandra E. Black Lecture to the Canadian Neurological Sciences Federation

Cerebral small vessel diseases (CSVDs) are among the most common age-related pathologies of the brain. Arteriolosclerosis and cerebral amyloid angiopathy (CAA) are the most common CSVDs. In addition to causing stroke and dementia, CSVDs can have diverse covert radiological manifestations on computed tomography and magnetic resonance imaging including lacunes, T2-weighted white matter hyperintensities, increased density of visible perivascular spaces, microbleeds and cortical superficial siderosis. Because they cannot be visualized directly, research on the pathophysiology of CSVD has been difficult. However, advances in quantitative imaging methods, including physiological imaging such as measurement of cerebrovascular reactivity and increased vascular permeability, are beginning to allow investigation of the early effects of CSVD in living people. Furthermore, genomics, metabolomics and proteomics have the potential to illuminate previously unrecognized pathways to CSVD that could be important targets for new clinical trials.

Post-Stroke Brain Health Monitoring and Optimization: A Narrative Review

Significant advancements have been made in recent years in the acute treatment and secondary prevention of stroke. However, a large proportion of stroke survivors will go on to have enduring physical, cognitive, and psychological disabilities from suboptimal post-stroke brain health. Impaired brain health following stroke thus warrants increased attention from clinicians and researchers alike. In this narrative review based on an open timeframe search of the PubMed, Scopus, and Web of Science databases, we define post-stroke brain health and appraise the body of research focused on modifiable vascular, lifestyle, and psychosocial factors for optimizing post-stroke brain health. In addition, we make clinical recommendations for the monitoring and management of post-stroke brain health at major post-stroke transition points centered on four key intertwined domains: cognition, psychosocial health, physical functioning, and global vascular health. Finally, we discuss potential future work in the field of post-stroke brain health, including the use of remote monitoring and interventions, neuromodulation, multi-morbidity interventions, enriched environments, and the need to address inequities in post-stroke brain health. As post-stroke brain health is a relatively new, rapidly evolving, and broad clinical and research field, this narrative review aims to identify and summarize the evidence base to help clinicians and researchers tailor their own approach to integrating post-stroke brain health into their practices.

Antiplatelet therapy and incident cognitive impairment or dementia-a systematic review and meta-analysis of randomised clinical trials

OBJECTIVE

The benefit of antiplatelet therapy in preventing cognitive impairment or dementia is uncertain. We investigated the association between antiplatelet therapy and incident cognitive impairment or dementia in randomised clinical trials.

METHODS

We searched PubMed, EMBASE and CENTRAL for randomised clinical trials published from database inception through 1 February 2023. Trials that evaluated the association of antiplatelet therapy with incident cognitive impairment or dementia were included. For single-agent antiplatelet, the control group was placebo. For dual agent antiplatelet therapy, the control group was single-agent monotherapy. A random-effects meta-analysis model was used to report pooled treatment effects and 95% confidence intervals (CIs). The primary outcome was incident cognitive impairment or dementia. Secondary outcomes included change in cognitive test scores.

RESULTS

A total of 11 randomised clinical trials were included (109,860 participants). All reported the incidence of cognitive impairment or dementia on follow-up. The mean (SD) age of trial participants was 66.2 (7.9) years. Antiplatelet therapy was not significantly associated with a reduced risk of cognitive impairment or dementia (11 trials; 109,860 participants) (3.49% versus 4.18% of patients over a mean trial follow-up of 5.8 years; odds ratio [OR], 0.94 [95% CI, 0.88-1.00]; absolute risk reduction, 0.2% [95% CI, -0.4% to 0.009%]; I2 = 0.0%). Antiplatelet therapy was not significantly associated with mean change in cognitive test scores.

CONCLUSION

In this meta-analysis, antiplatelet therapy was not significantly associated with a lower risk of incident cognitive impairment or dementia, but the CIs around this outcome do not exclude a modest preventative effect.

Associations Between Vascular Risk Factor Levels and Cognitive Decline Among Stroke Survivors

Importance

Incident stroke is associated with accelerated cognitive decline. Whether poststroke vascular risk factor levels are associated with faster cognitive decline is uncertain.

Objective

To evaluate associations of poststroke systolic blood pressure (SBP), glucose, and low-density lipoprotein (LDL) cholesterol levels with cognitive decline.

Design, Setting, and Participants

Individual participant data meta-analysis of 4 US cohort studies (conducted 1971-2019). Linear mixed-effects models estimated changes in cognition after incident stroke. Median (IQR) follow-up was 4.7 (2.6-7.9) years. Analysis began August 2021 and was completed March 2023.

Exposures

Time-dependent cumulative mean poststroke SBP, glucose, and LDL cholesterol levels.

Main Outcomes and Measures

The primary outcome was change in global cognition. Secondary outcomes were change in executive function and memory. Outcomes were standardized as t scores (mean [SD], 50 [10]); a 1-point difference represents a 0.1-SD difference in cognition.

Results

A total of 1120 eligible dementia-free individuals with incident stroke were identified; 982 (87.7%) had available covariate data and 138 (12.3%) were excluded for missing covariate data. Of the 982, 480 (48.9%) were female individuals, and 289 (29.4%) were Black individuals. The median age at incident stroke was 74.6 (IQR, 69.1-79.8; range, 44.1-96.4) years. Cumulative mean poststroke SBP and LDL cholesterol levels were not associated with any cognitive outcome. However, after accounting for cumulative mean poststroke SBP and LDL cholesterol levels, higher cumulative mean poststroke glucose level was associated with faster decline in global cognition (-0.04 points/y faster per each 10-mg/dL increase [95% CI, -0.08 to -0.001 points/y]; P = .046) but not executive function or memory. After restricting to 798 participants with apolipoprotein E4 (APOE4) data and controlling for APOE4 and APOE4 × time, higher cumulative mean poststroke glucose level was associated with a faster decline in global cognition in models without and with adjustment for cumulative mean poststroke SBP and LDL cholesterol levels (-0.05 points/y faster per 10-mg/dL increase [95% CI, -0.09 to -0.01 points/y]; P = .01; -0.07 points/y faster per 10-mg/dL increase [95% CI, -0.11 to -0.03 points/y]; P = .002) but not executive function or memory declines.

Conclusions and Relevance

In this cohort study, higher poststroke glucose levels were associated with faster global cognitive decline. We found no evidence that poststroke LDL cholesterol and SBP levels were associated with cognitive decline.

Efficacy and safety of oxiracetam in patients with vascular cognitive impairment: A multicenter, randomized, double-blinded, placebo-controlled, phase IV clinical trial

BACKGROUND

Oxiracetam may have a modest effect on preventing cognitive decline. Exercise can also enhance cognitive function. This trial aims to investigate the effect of oxiracetam on post-stroke cognitive impairment and explore whether this effect is modified by exercise. Furthermore, the mechanisms that mediate this effect will be investigated through a neural network analysis.

METHODS

This is a multicenter, randomized, double-blind, placebo-controlled phase IV trial. Patients who complained of cognitive decline 3 months after stroke and had a high risk of cognitive decline were eligible. Patients were randomly assigned to receive either 800 mg of oxiracetam or placebo twice daily for 36 weeks. After randomization, a predetermined exercise protocol was provided to each participant, and the degree of physical activity was assessed using wrist actigraphy at 4, 12, 24, and 36 weeks. Resting-state functional MRI was obtained in baseline and 36-week follow-up. Co-primary endpoints are changes in the Mini-Mental State Examination and Clinical Dementia Rating-Sum of Boxes. Secondary endpoints include changes in the NINDS-CSN VCIHS-Neuropsychology Protocol, Euro QoL, patient's global assessment, and functional network connectivity. If there is a significant difference in physical activity between the two groups, the interaction effect between physical activity and the treatment group will be examined. A total of 500 patients were enrolled from February 2018, and the last patient's final follow-up was completed in September 2022.

CONCLUSION

This trial is meaningful not only to prove the efficacy of oxiracetam, but also evaluate whether exercise can modify the effects of medication and how cognitive function can be restored. Trial registrationhttp://cris.nih.go.kr (KCT0005137).

Cerebral Small Vessel Disease-Related Dementia: More Questions Than Answers

Cerebral small vessel disease (CSVD) has emerged as a common factor driving age-dependent diseases, including stroke and dementia. CSVD-related dementia will affect a growing fraction of the aging population, requiring improved recognition, understanding, and treatments. This review describes evolving criteria and imaging biomarkers for the diagnosis of CSVD-related dementia. We describe diagnostic challenges, particularly in the context of mixed pathologies and the absence of highly effective biomarkers for CSVD-related dementia. We review evidence regarding CSVD as a risk factor for developing neurodegenerative disease and potential mechanisms by which CSVD leads to progressive brain injury. Finally, we summarize recent studies on the effects of major classes of cardiovascular medicines relevant to CSVD-related cognitive impairment. Although many key questions remain, the increased attention to CSVD has resulted in a sharper vision for what will be needed to meet the upcoming challenges imposed by this disease.

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.

Diagnosing vascular cognitive impairment: Current challenges and future perspectives

Cerebrovascular disease is a major cause of cognitive decline and dementia. This is referred to as vascular cognitive impairment (VCI). Diagnosing VCI is important, among others to optimize treatment to prevent further vascular injury. This narrative review addresses challenges in current diagnostic approaches to VCI and potential future developments. First we summarize how diagnostic criteria for VCI evolved over time. We then highlight challenges in diagnosing VCI in clinical practice: assessment of severity of vascular brain injury on brain imaging is often imprecise and the relation between vascular lesion burden and cognitive functioning shows high intersubject variability. This can make it difficult to establish causality in individual patients. Moreover, because VCI is essentially an umbrella term, it lacks specificity on disease mechanisms, prognosis, and treatment. We see the need for a fundamentally different approach to diagnosing VCI, which should be more dimensional, including multimodal quantitative assessment of injury, with more accurate estimation of cognitive impact, and include biological definitions of disease that can support further development of targeted treatment. Recent developments in the field that can form the basis of such an approach are discussed.

Framework for Clinical Trials in Cerebral Small Vessel Disease (FINESSE): A Review

Importance

Cerebral small vessel disease (SVD) causes a quarter of strokes and is the most common pathology underlying vascular cognitive impairment and dementia. An important step to developing new treatments is better trial methodology. Disease mechanisms in SVD differ from other stroke etiologies; therefore, treatments need to be evaluated in cohorts in which SVD has been well characterized. Furthermore, SVD itself can be caused by a number of different pathologies, the most common of which are arteriosclerosis and cerebral amyloid angiopathy. To date, there have been few sufficiently powered high-quality randomized clinical trials in SVD, and inconsistent trial methodology has made interpretation of some findings difficult.

Observations

To address these issues and develop guidelines for optimizing design of clinical trials in SVD, the Framework for Clinical Trials in Cerebral Small Vessel Disease (FINESSE) was created under the auspices of the International Society of Vascular Behavioral and Cognitive Disorders. Experts in relevant aspects of SVD trial methodology were convened, and a structured Delphi consensus process was used to develop recommendations. Areas in which recommendations were developed included optimal choice of study populations, choice of clinical end points, use of brain imaging as a surrogate outcome measure, use of circulating biomarkers for participant selection and as surrogate markers, novel trial designs, and prioritization of therapeutic agents using genetic data via Mendelian randomization.

Conclusions and Relevance

The FINESSE provides recommendations for trial design in SVD for which there are currently few effective treatments. However, new insights into understanding disease pathogenesis, particularly from recent genetic studies, provide novel pathways that could be therapeutically targeted. In addition, whether other currently available cardiovascular interventions are specifically effective in SVD, as opposed to other subtypes of stroke, remains uncertain. FINESSE provides a framework for design of trials examining such therapeutic approaches.

Association of Blood Pressure Lowering Intensity With White Matter Network Integrity in Patients With Cerebral Small Vessel Disease

BACKGROUND AND OBJECTIVES

Diffusion tensor imaging (DTI) networks integrate damage from a variety of pathologic processes in cerebral small vessel disease (SVD) and may be a sensitive marker to detect treatment effects. We determined whether brain network analysis could detect treatment effects in the PRESERVE trial data set, in which intensive vs standard blood pressure (BP) lowering was compared. The primary end point of DTI had not shown treatment differences.

METHODS

Participants with lacunar stroke were randomized to standard (systolic 130-140 mm Hg) or intensive (systolic ≤ 125 mm Hg) BP lowering and followed for 2 years with MRI at baseline and at 2 years. Graph theory-based metrics were derived from DTI data to produce a measure of network integrity weighted global efficiency and compared with individual MRI markers of DTI, brain volume, and white matter hyperintensities.

RESULTS

Data were available in 82 subjects: standard n = 40 (mean age 66.3 ± 1.5 years) and intensive n = 42 (mean age 69.6 ± 1.0 years). The mean (SD) systolic BP was reduced by 13(14) and 23(23) mm Hg in the standard and intensive groups, respectively (p < 0.001 between groups). Significant differences in diffusion network metrics were found, with improved network integrity (weighted global efficiency, p = 0.002) seen with intensive BP lowering. In contrast, there were no significant differences in individual MRI markers including DTI histogram metrics, brain volume, or white matter hyperintensities.

DISCUSSION

Brain network analysis may be a sensitive surrogate marker in trials in SVD. This work suggests that measures of brain network efficiency may be more sensitive to the effects of BP control treatment than conventional DTI metrics.

TRIAL REGISTRATION INFORMATION

The trial is registered with the ISRCTN Registry (ISRCTN37694103; doi.org/10.1186/ISRCTN37694103) and the NIHR Clinical Research Network (CRN 10962; public-odp.nihr.ac.uk/QvAJAXZfc/opendoc.htm?document=crncc_users%5Cfind%20a%20clinical%20research%20study.qvw&lang=en-US&host=QVS%40crn-prod-odp-pu&anonymous=true).

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that intensive BP lowering in patients with SVD results in improved brain network function when assessed by DTI-based brain network metrics.

Antiplatelets and Vascular Dementia: A Systematic Review

Vascular dementia (VD) is a neurocognitive disorder whose precise definition is still up for debate. VD generally refers to dementia that is primarily caused by cerebrovascular disease or impaired cerebral blood flow. It is a subset of vascular cognitive impairment, a class of diseases that relate any cerebrovascular injury as a causal or correlating factor for cognitive decline, most commonly seen in the elderly. Patients who present with both cognitive impairment and clinical or radiologic indications of cerebrovascular pathology should have vascular risk factors, particularly hypertension, examined and treated. While these strategies may be more effective at avoiding dementia than at ameliorating it, there is a compelling case for intensive secondary stroke prevention in these patients. Repeated stroke is related to an increased chance of cognitive decline, and poststroke dementia is connected with an increased risk of death. In general, most physicians follow recommendations for secondary stroke prevention in patients with VD, which can be accomplished by the use of antithrombotic medicines such as antiplatelets (aspirin, clopidogrel, ticlopidine, cilostazol, etc.). In individuals with a high risk of atherosclerosis and those with documented symptomatic cerebrovascular illness, antiplatelets treatment lowers the risk of stroke. While this therapy strategy of prevention and rigorous risk management has a compelling justification, there is only limited and indirect data to support it. The following systematic review examines the role of antiplatelets in the management of vascular dementia in published clinical trials and studies and comments on the current evidence available to support their use and highlights the need for further study.

Antithrombotic therapy to prevent cognitive decline in people with small vessel disease on neuroimaging but without dementia

BACKGROUND

Cerebral small vessel disease is a progressive disease of the brain's deep perforating blood vessels. It is usually diagnosed based on lesions seen on brain imaging. Cerebral small vessel disease is a common cause of stroke but can also cause a progressive cognitive decline. As antithrombotic therapy is an established treatment for stroke prevention, we sought to determine whether antithrombotic therapy might also be effective in preventing cognitive decline in people with small vessel disease.

OBJECTIVES

To assess the effects of antithrombotic therapy for prevention of cognitive decline in people with small vessel disease on neuroimaging but without dementia.

SEARCH METHODS

We searched ALOIS, the Cochrane Dementia and Cognitive Improvement Review Group's Specialised Register, and the Cochrane Stroke Group's Specialised Register; the most recent search was on 21 July 2021. We also searched MEDLINE, Embase, four other databases and two trials registries. We searched the reference lists of the articles retrieved from these searches. As trials with a stroke focus may include relevant subgroup data, we complemented these searches with a focussed search of all antithrombotic titles in the Cochrane Stroke Group database.  SELECTION CRITERIA: We included randomised controlled trials (RCT) of people with neuroimaging evidence of at least mild cerebral small vessel disease (defined here as white matter hyperintensities, lacunes of presumed vascular origin and subcortical infarcts) but with no evidence of dementia. The trials had to compare antithrombotic therapy of minimum 24 weeks' duration to no antithrombotic therapy (either placebo or treatment as usual), or compare different antithrombotic treatment regimens. Antithrombotic therapy could include antiplatelet agents (as monotherapy or combination therapy), anticoagulants or a combination.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all the titles identified by the searches. We assessed full texts for eligibility for inclusion according to our prespecified selection criteria, extracted data to a proforma and assessed risk of bias using the Cochrane tool for RCTs. We evaluated the certainty of evidence using GRADE. Due to heterogeneity across included participants, interventions and outcomes of eligible trials, it was not possible to perform meta-analyses.

MAIN RESULTS

We included three RCTs (3384 participants). One study investigated the effect of antithrombotic therapy in participants not yet on antithrombotic therapy; two studies investigated the effect of additional antithrombotic therapy, one in a population already taking a single antithrombotic agent and one in a mixed population (participants on an antithrombotic drug and antithrombotic-naive participants). Intervention and follow-up durations varied from 24 weeks to four years. Jia 2016 was a placebo-controlled trial assessing 24 weeks of treatment with DL-3-n-butylphthalide (a compound with multimodal actions, including a putative antiplatelet effect) in 280 Chinese participants with vascular cognitive impairment caused by subcortical ischaemic small vessel disease, but without dementia. There was very low-certainty evidence for a small difference in cognitive test scores favouring treatment with DL-3-n-butylphthalide, as measured by the 12-item Alzheimer's Disease Assessment Scale-Cognitive subscale (adjusted mean difference -1.07, 95% confidence interval (CI) -2.02 to -0.12), but this difference may not be clinically relevant. There was also very low-certainty evidence for greater proportional improvement measured with the Clinician Interview-Based Impression of Change-Plus Caregiver Input (57% with DL-3-n-butylphthalide versus 42% with placebo; P = 0.01), but there was no difference in other measures of cognition (Mini-Mental State Examination and Clinical Dementia Rating) or function. There was no evidence of a difference in adverse events between treatment groups. The SILENCE RCT compared antithrombotic therapy (aspirin) and placebo during four years of treatment in 83 participants with 'silent brain infarcts' who were on no prior antithrombotic therapy. There was very low-certainty evidence for no difference between groups across various measures of cognition and function, rates of stroke or adverse events. The Secondary Prevention of Subcortical Stroke Study (SPS3) compared dual antiplatelet therapy (clopidogrel plus aspirin) to aspirin alone in 3020 participants with recent lacunar stroke. There was low-certainty evidence of no effect on cognitive outcomes as measured by the Cognitive Abilities Screening Instruments (CASI) assessed annually over five years. There was also low-certainty evidence of no difference in the annual incidence of mild cognitive decline between the two treatment groups (9.7% with dual antiplatelet therapy versus 9.9% with aspirin), or the annual stroke recurrence rate (2.5% with dual antiplatelet therapy versus 2.7% with aspirin). Bleeding risk may be higher with dual antiplatelet therapy (hazard ratio (HR) 2.15, 95% CI 1.49 to 3.11; low certainty evidence), but there may be no significant increase in intracerebral bleeding risk (HR 1.52, 95% CI 0.79 to 2.93; low-certainty evidence). None of the included trials assessed the incidence of new dementia.

AUTHORS' CONCLUSIONS

We found no convincing evidence to suggest any clinically relevant cognitive benefit of using antithrombotic therapy in addition to standard treatment in people with cerebral small vessel disease but without dementia, but there may be an increased bleeding risk with this approach. There was marked heterogeneity across the trials and the certainty of the evidence was generally poor.

2021 Taiwan Stroke Society Guidelines of blood pressure control for ischemic stroke prevention

BACKGROUND

Since the publication of the 2015 Taiwan Stroke Society Blood Pressure for Treatment and Prevention of Stroke Guideline (2015 TSS BP Guideline), several new clinical studies have addressed whether a stricter blood pressure (BP) target would be effective for stroke prevention.

METHODS

TSS guideline consensus group provides recommendations on BP targets for stroke prevention based on updated evidences.

RESULTS

The present guideline covers five topics: (1) diagnosis of hypertension; (2) BP control and primary prevention of ischemic stroke; (3) BP control and secondary prevention of ischemic stroke; (4) BP control and secondary prevention of large artery atherosclerosis ischemic stroke; and (5) BP control and secondary prevention of small vessel occlusion ischemic stroke.

CONCLUSION

The BP target for most stroke patients with hypertension is <130/80 mm Hg.

Relationship Between Hypertension and Cognitive Function in an Elderly Population: A Population-Based Study in Rural Northern China

The burden of cognitive impairment and dementia is particularly severe in low- and middle-income countries. Although hypertension is an important risk factor for cognitive impairment, the influence of different hypertension classification on cognitive impairment remains controversial. To explore the impact of hypertension and hypertension classification on cognitive function, this study was based on a low-income population aged over 60 years in northern China. This population-based, cross-sectional study was conducted from April 2014 to January 2015 in rural areas of Tianjin, China. A total of 1,171 participants aged ≥ 60 years were included. Participants were interviewed by professional researchers face-to-face, using the pre-designed questionnaire. Cognitive function was assessed using the Mini-mental State Examination (MMSE). Multivariate regression analysis was used to calculate the odds ratio (OR) value. There was a significant association between hypertension and cognitive impairment (OR, 1.415; 95% CI: 1.005–1.992; P = 0.047) and a significant positive association between stage 3 hypertension (OR, 1.734; 95% CI: 1.131–2.656; P = 0.012) and the prevalence of cognitive impairment. To prevent dementia, clinicians should consider the cognitive function and blood pressure control of low-income individuals aged over 60 years with hypertension in northern China, especially those with stage 3 hypertension. In addition, the inconsistent effects of blood pressure on different cognitive functions should also be considered; special attention should be paid to orientation and concentration.

Post-Stroke Cognitive Impairment and Dementia

Poststroke cognitive impairment and dementia (PSCID) is a major source of morbidity and mortality after stroke worldwide. PSCID occurs as a consequence of ischemic stroke, intracerebral hemorrhage, or subarachnoid hemorrhage. Cognitive impairment and dementia manifesting after a clinical stroke is categorized as vascular even in people with comorbid neurodegenerative pathology, which is common in elderly individuals and can contribute to the clinical expression of PSCID. Manifestations of cerebral small vessel disease, such as covert brain infarcts, white matter lesions, microbleeds, and cortical microinfarcts, are also common in patients with stroke and likewise contribute to cognitive outcomes. Although studies of PSCID historically varied in the approach to timing and methods of diagnosis, most of them demonstrate that older age, lower educational status, socioeconomic disparities, premorbid cognitive or functional decline, life-course exposure to vascular risk factors, and a history of prior stroke increase risk of PSCID. Stroke characteristics, in particular stroke severity, lesion volume, lesion location, multiplicity and recurrence, also influence PSCID risk. Understanding the complex interaction between an acute stroke event and preexisting brain pathology remains a priority and will be critical for developing strategies for personalized prediction, prevention, targeted interventions, and rehabilitation. Current challenges in the field relate to a lack of harmonization of definition and classification of PSCID, timing of diagnosis, approaches to neurocognitive assessment, and duration of follow-up after stroke. However, evolving knowledge on pathophysiology, neuroimaging, and biomarkers offers potential for clinical applications and may inform clinical trials. Preventing stroke and PSCID remains a cornerstone of any strategy to achieve optimal brain health. We summarize recent developments in the field and discuss future directions closing with a call for action to systematically include cognitive outcome assessment into any clinical studies of poststroke outcome.

Blood Pressure and Vascular Cognitive Impairment

High blood pressure (BP) is detrimental to brain health. High BP contributes to cognitive impairment and dementia through pathways independent of clinical stroke. Emerging evidence shows that the deleterious effect of high BP on cognition occurs across the life span, increasing the risk for early-onset and late-life dementia. The term vascular cognitive impairment includes cognitive disorders associated with cerebrovascular disease, regardless of the pathogenesis. This focused report is a narrative review that aims to summarize the epidemiology of BP and vascular cognitive impairment, including differences by sex, race, and ethnicity, as well as the management and reversibility of BP and vascular cognitive impairment. It also discusses knowledge gaps and future directions.

Ticagrelor for prevention of stroke and cognitive impairment in patients with vascular high-risk factors: A meta-analysis of randomized controlled trials

BACKGROUND

In recent randomized controlled studies, the prevention of stroke and cognitive function of ticagrelor has been controversial. We conducted a meta-analysis to compare ticagrelor with other antiplatelet treatment in patients with vascular high-risk factors disease, defined as acute coronary syndrome, stroke or transient ischemic attack, coronary artery disease or peripheral artery disease.

METHODS

We searched the PubMed, Embase, and Cochrane libraries for published randomized controlled trials and additional available data from ClinicalTrials.gov. The primary outcome was related adverse stroke events and the secondary outcome was cognitive function related adverse events. The outcomes were statistically analyzed using Peto odds ratio.

RESULTS

12 RCTs with 105,654 patients were included in meta-analysis. Primary outcomes: all stroke (OR 0.84, 95%CI 0.78-0.90, P < 0.001); Secondary outcomes: ischemic stroke (OR 0.83, 95%CI 0.77-0.90, P < 0.001), transient ischemic attack (OR 0.78, 95%CI 0.62-0.97, P = 0.029), intracranial hemorrhage (OR 1.33, 95%CI 1.09-1.61, P = 0.005), Parkinson's disease (OR 0.30, 95%CI 0.12-0.72, P = 0.007), dementia (OR 0.31, 95%CI 0.13-0.77, P = 0.012), dizziness (OR: 1.39, 95%CI 1.03-1.87, P = 0.032), insomnia (OR 1.45, 95%CI 1.05-2.00, P = 0.026).

CONCLUSIONS

Ticagrelor may provide more favorable outcomes for all stroke, ischemic stroke, and transient ischemic attack prevention in patients with vascular high-risk factors. However, this benefit may come with the cost of intracranial hemorrhage, dizziness and insomnia. Ticagrelor may reduce the risk of dementia and Parkinson's disease, although available data are limited.

The effects of blood pressure on post stroke cognitive impairment: BP and PSCI

Cognitive function following acute ischemic stroke (AIS) is critical to prognosis and quality of life. Hypertension is a risk factor for stroke and is associated with post stroke cognitive impairment (PSCI). However, the optimal blood pressure parameters after AIS is unknown. This is a sub‐study of the Impairment of CognitiON and Sleep after acute ischemic stroke or transient ischemic attack in Chinese patients (ICONS) study conducted between August 2015 and March 2018. Cognition was assessed at two‐week (2w), three‐month (3 m), and twelve‐month (12 m) by Montreal Cognitive Assessment (MoCA). A total of 682 participants who met the inclusion criteria were enrolled. The primary outcome was cognitive changes after 3 and 12 months post stroke. Among 682 participants, the mean age was 59.35 ± 10.40 years and 72.29% were men. PSCI patients with high systolic blood pressure (SBP ≥140 mm Hg) at 3 m not only had worse cognition as evidenced by MoCA scores at 3 m but also predicted worse scores at 12 m. When participants were stratified into cognitively stable/improved (MoCA score ≥0, 2w vs. 12 m) and cognitively impaired (MoCA score ≤‐2, 2w vs. 12 m), those with high SBP were more likely to be cognitively impaired (OR 2.17, 95%CI 1.12–4.21, p < .05) and less likely to be cognitively stable/improved (OR 0.66, 95%CI 0.44–0.99, p < .05). SBP more than 140 mm Hg is associated with worse cognitive performance after ischemic stroke. Patients with SBP lower than 140 mm Hg have better cognitive outcome at 3‐month and 1 year after stroke.

Sex differences in predictors for cognitive decline and dementia in people with stroke or transient ischemic attack in the PROGRESS trial

BACKGROUND

Stroke and transient ischemic attack confer greater risk of cognitive decline and dementia.

AIMS

We used data from the Perindopril Protection Against Recurrent Stroke Study (PROGRESS), a blood pressure-lowering randomized controlled trial in stroke/transient ischemic attack. We evaluated overall and sex-specific differences in treatment effects for cognitive decline/dementia, as well as associations with vascular and stroke-specific predictors,considering death as a competing risk.

METHODS

Multinomial logistic regression was used to estimate overall and sex-specific odds ratios (OR) (95% confidence intervals (CI)) for treatment effects and predictors associated with the risk of cognitive decline/dementia, and the women-to-men ratio of odds ratio (RORs).

RESULTS

Over a median four years, 763 cognitive decline/dementia (30.9% women) were recorded in 5888 participants. Women had lower odds of cognitive decline/dementia than men (OR 0.78, 95%CI 0.63-0.95). Active treatment was associated with lower odds of cognitive decline/dementia (0.84, 0.72-0.98), with no evidence of sex difference. Higher education (0.96,0.94-0.98 (per year)) and baseline Mini-Mental State Examination (MMSE)) were associated with lower odds of cognitive decline/dementia (0.84,0.82-0.86 (per point higher)). Higher diastolic blood pressure (1.11,1.02-1.20 (per 10 mmHg)), low estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2 (1.27,1.03-1.58), and peripheral arterial disease (1.78,1.26-2.52) were associated with higher odds of cognitive decline/dementia. APOE ɛ4 was not associated with cognitive decline/dementia (1.05 (0.85-1.30)). Low eGFR was more strongly associated with cognitive decline/dementia in women than men (RORs, 1.60 (1.03-2.48)). Diabetes was more strongly associated with men than women.

CONCLUSIONS

Several risk factors were associated with cognitive decline/dementia in people with prior stroke/transient ischemic attack, with notable sex differences. Long-term cognitive sequelae of stroke should be considered to strengthen joint prevention strategies for stroke, cognitive decline, and dementia.Trial Registration: This trial was not registered because enrolment began before 1 July 2005.

Evaluation of Intensive vs Standard Blood Pressure Reduction and Association With Cognitive Decline and Dementia: A Systematic Review and Meta-analysis

IMPORTANCE

Optimal blood pressure (BP) targets for the prevention of cognitive impairment remain uncertain.

OBJECTIVE

To explore the association of intensive (ie, lower than usual) BP reduction vs standard BP management with the incidence of cognitive decline and dementia in adults with hypertension.

DATA SOURCES AND STUDY SELECTION

A systematic review and meta-analysis of randomized clinical trials that evaluated the association of intensive systolic BP lowering on cognitive outcomes by searching MEDLINE, Embase, CENTRAL, Web of Science, CINAHL, PsycINFO, the International Clinical Trials Registry Platform, and ClinicalTrials.gov from database inception to October 27, 2020.

DATA EXTRACTION AND SYNTHESIS

Data screening and extraction were performed independently by 2 reviewers based on Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The risk of bias was assessed using the Cochrane risk of bias 2 tool. Random-effects models with the inverse variance method were used for pooled analyses. The presence of potential heterogeneity was evaluated with the I2 index.

MAIN OUTCOMES AND MEASURES

The primary outcome was cognitive decline. Secondary outcomes included the incidence of dementia, mild cognitive impairment (MCI), cerebrovascular events, serious adverse events, and all-cause mortality.

RESULTS

From 7755 citations, we identified 16 publications from 5 trials with 17 396 participants (mean age, 65.7 years [range, 63.0-80.5 years]; 10 562 [60.5%] men) and 2 additional ongoing trials. All 5 concluded trials included in quantitative analyses were considered at unclear to high risk of bias. The mean follow-up duration was 3.3 years (range, 2.0 to 4.7 years). Intensive BP reduction was not significantly associated with global cognitive performance (standardized mean difference, 0.01; 95% CI, -0.04 to 0.06; I2 = 0%; 4 trials; 5246 patients), incidence of dementia (risk ratio [RR], 1.09; 95% CI, 0.32 to 3.67; I2 = 27%; 2 trials; 9444 patients) or incidence of MCI (RR, 0.91; 95% CI, 0.73 to 1.14; I2 = 74%; 2 trials; 10 774 patients) when compared with standard treatment. However, a reduction of cerebrovascular events in the intensive group was found (RR, 0.79; 95% CI, 0.67 to 0.93; I2 = 0%; 5 trials; 17 396 patients) without an increased risk of serious adverse events or mortality.

CONCLUSIONS AND RELEVANCE

In this study, there was no significant association between BP reduction and lower risk of cognitive decline, dementia, or MCI. The certainty of this evidence was rated low because of the limited sample size, the risk of bias of included trials, and the observed statistical heterogeneity. Therefore, current available evidence does not justify the use of lower BP targets for the prevention of cognitive decline and dementia.

Cognitive, Functional, and Mortality Outcomes of Attenuated Delirium Syndrome in Stroke Survivors

OBJECTIVES

There is a knowledge gap on the prognostic significance of subsyndromes of delirium. We describe the association of poststroke attenuated delirium syndrome (ADS) with cognitive, functional, and mortality outcomes at 3 months.

METHODS

A longitudinal observational study in which repeated assessments for delirium symptoms were conducted in the first week of stroke using the confusion assessment method. Attenuated delirium syndrome was characterized in survivors who were free of the full delirium syndrome but had ≥2 core features of delirium. Baseline and follow-up assessments were conducted using the Mini-Mental State Examination (MMSE), 10-word list learning and delayed recall test, Animal naming test, and Barthel index.

RESULTS

Among 150 participants recruited consecutively over 2 years, ADS was present in 32 (21.3%). Of 121 who were free of the full delirium syndrome, 21 (17.4%) had died by 3 months. Those who survived were more likely to be receiving treatment for systemic hypertension (88.5%, P = .007). In analyses adjusting for the effect of age, economic status, and systemic hypertension, ADS in the first week of stroke predicted cognitive decline at 3 months ([mean difference (MD) in MMSE scores = -3.8, 95% CI = -7.0 to -0.7, P = .019]). However, ADS was not associated with greater decline in activities of daily life (MD = -0.4, 95% CI = -2.8 to 2.0) or significant odds ratio (OR) of mortality (OR = 2.3, 95% CI = 0.8-6.3).

CONCLUSION

Attenuated delirium syndrome may be an important marker of cognitive impairment at 3 months poststroke. Its detection may lead to identification of stroke survivors who are likely to benefit from evidence-based preventive interventions for poststroke cognitive decline.

European Stroke Organisation and European Academy of Neurology joint guidelines on post-stroke cognitive impairment

BACKGROUND AND PURPOSE

The optimal management of post-stroke cognitive impairment (PSCI) remains controversial. These joint European Stroke Organisation (ESO) and European Academy of Neurology (EAN) guidelines provide evidence-based recommendations to assist clinicians in decision making regarding prevention, diagnosis, treatment and prognosis.

METHODS

Guidelines were developed according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations.

RESULTS

There was limited randomized controlled trial (RCT) evidence regarding single or multicomponent interventions to prevent post-stroke cognitive decline. Lifestyle interventions and treating vascular risk factors have many health benefits, but a cognitive effect is not proven. We found no evidence regarding routine cognitive screening following stroke, but recognize the importance of targeted cognitive assessment. We describe the accuracy of various cognitive screening tests, but found no clearly superior approach to testing. There was insufficient evidence to make a recommendation for use of cholinesterase inhibitors, memantine nootropics or cognitive rehabilitation. There was limited evidence on the use of prediction tools for post-stroke cognition. The association between PSCI and acute structural brain imaging features was unclear, although the presence of substantial white matter hyperintensities of presumed vascular origin on brain magnetic resonance imaging may help predict cognitive outcomes.

CONCLUSIONS

These guidelines highlight fundamental areas where robust evidence is lacking. Further definitive RCTs are needed, and we suggest priority areas for future research.

European Stroke Organisation and European Academy of Neurology joint guidelines on post-stroke cognitive impairment

The optimal management of post-stroke cognitive impairment remains controversial. These joint European Stroke Organisation (ESO) and European Academy of Neurology (EAN) guidelines provide evidence-based recommendations to assist clinicians in decision making around prevention, diagnosis, treatment and prognosis. These guidelines were developed according to ESO standard operating procedure and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and, where possible, meta-analyses of the literature, assessed the quality of the available evidence and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations based on the GRADE approach. There was limited randomised controlled trial evidence regarding single or multicomponent interventions to prevent post-stroke cognitive decline. Interventions to improve lifestyle and treat vascular risk factors may have many health benefits but a beneficial effect on cognition is not proven. We found no evidence around routine cognitive screening following stroke but recognise the importance of targeted cognitive assessment. We described the accuracy of various cognitive screening tests but found no clearly superior approach to testing. There was insufficient evidence to make a recommendation for use of cholinesterase inhibitors, memantine nootropics or cognitive rehabilitation. There was limited evidence on the use of prediction tools for post-stroke cognitive syndromes (cognitive impairment, dementia and delirium). The association between post-stroke cognitive impairment and most acute structural brain imaging features was unclear, although the presence of substantial white matter hyperintensities of presumed vascular origin on acute MRI brain may help predict cognitive outcomes. These guidelines have highlighted fundamental areas where robust evidence is lacking. Further, definitive randomised controlled trials are needed, and we suggest priority areas for future research.

ESO Guideline on covert cerebral small vessel disease

'Covert' cerebral small vessel disease (ccSVD) is common on neuroimaging in persons without overt neurological manifestations, and increases the risk of future stroke, cognitive impairment, dependency, and death. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist with clinical decisions about management of ccSVD, specifically white matter hyperintensities and lacunes, to prevent adverse clinical outcomes. The guidelines were developed according to ESO standard operating procedures and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. We prioritised the clinical outcomes of stroke, cognitive decline or dementia, dependency, death, mobility and mood disorders, and interventions of blood pressure lowering, antiplatelet drugs, lipid lowering, lifestyle modifications, glucose lowering and conventional treatments for dementia. We systematically reviewed the literature, assessed the evidence, formulated evidence-based recommendations where feasible, and expert consensus statements. We found little direct evidence, mostly of low quality. We recommend patients with ccSVD and hypertension to have their blood pressure well controlled; lower blood pressure targets may reduce ccSVD progression. We do not recommend antiplatelet drugs such as aspirin in ccSVD. We found little evidence on lipid lowering in ccSVD. Smoking cessation is a health priority. We recommend regular exercise which may benefit cognition, and a healthy diet, good sleep habits, avoiding obesity and stress for general health reasons. In ccSVD, we found no evidence for glucose control in the absence of diabetes or for conventional Alzheimer dementia treatments. Randomised controlled trials with clinical endpoints are a priority for ccSVD.

PRESERVE: Randomized Trial of Intensive Versus Standard Blood Pressure Control in Small Vessel Disease

[Figure: see text].

Functional health and white matter hyperintensities as effect modifiers of blood pressure-lowering on cognitive function and vascular events in older Secondary Prevention of Small Subcortical Strokes trial participants

OBJECTIVE

To determine whether cerebral small vessel disease or disability modify the effect of SBP treatment on cognitive and vascular outcomes in older patients with recent lacunar stroke.

METHODS

Participants aged at least 65 years of the Secondary Prevention of Small Subcortical Strokes Trial were randomized to a higher (130-149 mmHg) or lower (<130 mmHg) SBP target. The primary outcome was change in cognitive function (Cognitive Abilities Screening Instrument); secondary outcomes were incident mild cognitive impairment, stroke, major vascular events (all-stroke, myocardial infarction), and all-cause death. Results were stratified by severity of white matter hyperintensities (WMH; none/mild, moderate, severe) on baseline MRI, and by disability (no vs. at least one limitation in activities of daily living).

RESULTS

One thousand, two hundred and sixty-three participants (mean age 73.8 ± 5.9 years, 40% women) were included. Participants with severe WMH or disability had worse cognitive function at baseline and after a mean follow-up of 3.9 years. No significant interactions existed between treatment group and effect modifiers (WMH, disability) for change in cognitive function (P for interaction 0.42 and 0.66, respectively). A lower SBP target appeared more beneficial among those with worse WMH burden for vascular outcomes (P for interaction = 0.01 for stroke and 0.03 for major vascular events).

CONCLUSION

There was no difference in the effect of lowering SBP to less than 130 mmHg on cognitive function by cerebral small vessel disease or disability among older adults with a history of lacunar stroke. Those with evidence of small vessel disease may derive greater benefit from lower SBP on prevention of subsequent vascular events.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT00059306.

Pharmacological treatment of hypertension in people without prior cerebrovascular disease for the prevention of cognitive impairment and dementia

BACKGROUND

This is an update of a Cochrane Review first published in 2006 (McGuinness 2006), and previously updated in 2009 (McGuinness 2009). Hypertension is a risk factor for dementia. Observational studies suggest antihypertensive treatment is associated with lower incidences of cognitive impairment and dementia. There is already clear evidence to support the treatment of hypertension after stroke.

OBJECTIVES

To assess whether pharmacological treatment of hypertension can prevent cognitive impairment or dementia in people who have no history of cerebrovascular disease.

SEARCH METHODS

We searched the Specialised Register of the Cochrane Dementia and Cognitive Improvement Group, CENTRAL, MEDLINE, Embase, three other databases, as well as many trials registries and grey literature sources, most recently on 7 July 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in which pharmacological interventions to treat hypertension were given for at least 12 months. We excluded trials of pharmacological interventions to lower blood pressure in non-hypertensive participants. We also excluded trials conducted solely in people with stroke.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We collected information regarding incidence of dementia, cognitive decline, change in blood pressure, adverse effects and quality of life. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

We included 12 studies, totaling 30,412 participants, in this review. Eight studies compared active treatment with placebo. Of the four non-placebo-controlled studies, two compared intensive versus standard blood pressure reduction. The two final included studies compared different classes of antihypertensive drug. Study durations varied from one to five years. The combined result of four placebo-controlled trials that reported incident dementia indicated no evidence of a difference in the risk of dementia between the antihypertensive treatment group and the placebo group (236/7767 versus 259/7660, odds ratio (OR) 0.89, 95% confidence interval (CI) 0.72 to 1.09; very low certainty evidence, downgraded due to study limitations and indirectness). The combined results from five placebo-controlled trials that reported change in Mini-Mental State Examination (MMSE) may indicate a modest benefit from antihypertensive treatment (mean difference (MD) 0.20, 95% CI 0.10 to 0.29; very low certainty evidence, downgraded due to study limitations, indirectness and imprecision). The certainty of evidence for both cognitive outcomes was downgraded on the basis of study limitations and indirectness. Study durations were too short, overall, to expect a significant difference in dementia rates between groups. Dementia and cognitive decline were secondary outcomes for most studies. Additional sources of bias include: the use of antihypertensive medication by the placebo group in the placebo-controlled trials; failure to reach recruitment targets; and early termination of studies on safety grounds. Meta-analysis of the placebo-controlled trials reporting results found a mean change in systolic blood pressure of -9.25 mmHg (95% CI -9.73, -8.78) between treatment (n = 8973) and placebo (n = 8820) groups, and a mean change in diastolic blood pressure of -2.47 mmHg (95% CI -2.70, -2.24) between treatment (n = 7700) and placebo (n = 7509) groups (both low certainty evidence downgraded on the basis of study limitations and inconsistency). Three trials - SHEP 1991, LOMIR MCT IL 1996 and MRC 1996 - reported more withdrawals due to adverse events in active treatment groups than placebo groups. Participants on active treatment in Syst Eur 1998 were less likely to discontinue treatment due to side effects, and participants on active treatment in HYVET 2008 reported fewer 'serious adverse events' than in the placebo group. There was no evidence of a difference in withdrawals rates between groups in SCOPE 2003, and results were unclear for Perez Stable 2000 and Zhang 2018. Heterogeneity precluded meta-analysis. Five of the placebo-controlled trials provided quality of life (QOL) data. Heterogeneity again precluded meta-analysis. SHEP 1991, Syst Eur 1998 and HYVET 2008 reported no evidence of a difference in QOL measures between active treatment and placebo groups over time. The SCOPE 2003 sub-study (Degl'Innocenti 2004) showed a smaller drop in QOL measures in the active treatment compared to the placebo group. LOMIR MCT IL 1996 reported an improvement in a QOL measure at twelve months in one active treatment group and deterioration in another.

AUTHORS' CONCLUSIONS

High certainty randomised controlled trial evidence regarding the effect of hypertension treatment on dementia and cognitive decline does not yet exist. The studies included in this review provide low certainty evidence (downgraded primarily due to study limitations and indirectness) that pharmacological treatment of hypertension, in people without prior cerebrovascular disease, leads to less cognitive decline compared to controls. This difference is below the level considered clinically significant. The studies included in this review also provide very low certainty evidence that pharmacological treatment of hypertension, in people without prior cerebrovascular disease, prevents dementia.

The Relationship Between Glucose Control and Cognitive Function in People With Diabetes After a Lacunar Stroke

CONTEXT

Lacunar strokes and diabetes are risk factors for cognitive dysfunction. Elucidating modifiable risk factors for cognitive dysfunction has great public health implications. One factor may be glycemic status, as measured by glycated hemoglobin (A1c).

OBJECTIVE

The aim of this study was to assess the relationship between A1c and cognitive function in lacunar stroke patients with diabetes.

METHODS

The effect of baseline and follow-up A1c on the baseline and the change in Cognitive Assessment Screening Instrument (CASI) score over time among participants with a median of 2 cognitive assessments (range, 1-5) was examined in 942 individuals with diabetes and a lacunar stroke who participated in the Secondary Prevention of Small Subcortical Strokes (SPS3) trial (ClinicalTrials.gov No. NCT00059306).

RESULTS

Every 1% higher baseline A1c was associated with a 0.06 lower standardized CASI z score (95% CI, -0.101 to -0.018). Higher baseline A1c values were associated with lower CASI z scores over time (P for interaction = .037). A 1% increase in A1c over time corresponded with a CASI score decrease of 0.021 (95% CI, -0.0043 to -0.038) during follow-up. All these remained statistically significant after adjustment for age, sex, education, race, depression, hypertension, hyperlipidemia, body mass index, cardiovascular disease, obstructive sleep apnea, diabetic retinopathy, nephropathy insulin use, and white-matter abnormalities.

CONCLUSION

This analysis of lacunar stroke patients with diabetes demonstrates a relationship between A1c and change in cognitive scores over time. Intervention studies are needed to delineate whether better glucose control could slow the rate of cognitive decline in this high-risk population.

Blood pressure, blood pressure variability and the risk of poststroke dementia

OBJECTIVE

High blood pressure and blood pressure variability are potential, modifiable risk factors of poststroke dementia. We aimed to investigate the association between achieved blood pressure, blood pressure variability and poststroke dementia.

METHODS

We studied 17 064 patients with noncardioembolic ischemic stroke included in the Prevention Regimen for Effectively avoiding Second Strokes (PRoFESS) trial. We analysed the data as a single observational cohort. We studied mean achieved SBP and DBP and blood pressure variability defined as coefficient of variation (SD/mean∗100). The association between blood pressure and dementia was investigated with logistic regression analysis, correcting for sociodemographic factors and cardiovascular risk factors.

RESULTS

During 39 818 person-years of follow-up, 817 patients were diagnosed with dementia (2.1 per 100 person-years). We found a significant nonlinear association between mean SBP and the risk of dementia, implying a U-shaped association between mean SBP and dementia. Mean SBP of 120-129 mmHg was associated with a significantly higher risk of dementia than 130-139 mmHg [odds ratio (OR) 1.28; 95% confidence interval (95% CI) 1.03-1.58]. There was no indication of a U-shaped association between mean DBP and dementia, and no significant association between mean DBP categories and dementia. Higher blood pressure variability was associated with an increased risk of dementia (OR 1.06 per point increase, 95% CI 1.02-1.04), independent of mean SBP.

CONCLUSION

Among patients with a recent noncardioembolic ischemic stroke, there appears to be a U-shaped association between achieved SBP and dementia. High blood pressure variability is associated with an increased risk of poststroke dementia.

CD34+ cells and endothelial progenitor cell subpopulations are associated with cerebral small vessel disease burden

Background: Endothelial dysfunction is considered to be involved in the pathogenesis of cerebral small vessel disease (CSVD). Endothelial progenitor cells are associated with endothelial dysfunction. The present study was designed to investigate the correlation between the populations of circulating CD34-positive cells and endothelial progenitor cells and CSVD burden. Methodology & results: A total of 364 patients with confirmed diagnosis of CSVD were included in this prospective study. Multiple ordinal logistic regression analyses showed that subjects with higher CSVD burden had significantly decreased circulating CD34⁺ cell level (odds ratio [OR], 0.42; p = 0.034) and significantly increased levels of circulating CD34⁺CD133⁺CD309⁺ and CD34⁺CD133⁺ cells (OR 1.07, p = 0.031; OR 1.03, p = 0.001, respectively), compared with patients with lower CSVD burden. Conclusion: The findings suggest that the levels of circulating CD34⁺ cells, CD34⁺CD133⁺CD309⁺ cells and CD34⁺CD133⁺ cells may be used as potential biomarkers to monitor the disease progression of CSVD.

Immunological mechanisms in poststroke dementia

PURPOSE OF REVIEW

To review new evidence on links between poststroke dementia and inflammation.

RECENT FINDINGS

Although there are still no treatments for poststroke dementia, recent evidence has improved our understanding that stroke increases the risk of incident dementia and worsens cognitive trajectory for at least a decade afterwards. Within approximately the first year dementia onset is associated with stroke severity and location, whereas later absolute risk is associated with more traditional dementia risk factors, such as age and imaging findings. The molecular mechanisms that underlie increased risk of incident dementia in stroke survivors remain unproven; however new data in both human and animal studies suggests links between cognitive decline and inflammation. These point to a model where chronic brain inflammation, provoked by inefficient clearance of myelin debris and a prolonged innate and adaptive immune response, causes poststroke dementia. These localized immune events in the brain may themselves be influenced by the peripheral immune state at key times after stroke.

SUMMARY

This review recaps clinical evidence on poststroke dementia, new mechanistic links between the chronic inflammatory response to stroke and poststroke dementia, and proposes a model of immune-mediated neurodegeneration after stroke.

Stroke Prevention in Atrial Fibrillation

Ischemic strokes related to atrial fibrillation are highly prevalent, presenting with severe neurologic syndromes and associated with high risk of recurrence. Although advances have been made in both primary and secondary stroke prevention for patients with atrial fibrillation, the long-term risks for stroke recurrence and bleeding complications from antithrombotic treatment remain substantial. We summarize the major advances in stroke prevention for patients with atrial fibrillation during the past 30 years and focus on novel diagnostic and treatment approaches currently under investigation in ongoing clinical trials. Non–vitamin K antagonist oral anticoagulants have been proven to be safer and equally effective compared with warfarin in stroke prevention for patients with nonvalvular atrial fibrillation. Non–vitamin K antagonist oral anticoagulants are being investigated for the treatment of patients with atrial fibrillation and rheumatic heart disease, for the treatment of patients with recent embolic stroke of undetermined source and indirect evidence of cardiac embolism, and in the prevention of vascular-mediated cognitive decline in patients with atrial fibrillation. Multiple clinical trials are assessing the optimal timing of non–vitamin K antagonist oral anticoagulant initiation after a recent ischemic stroke and the benefit:harm ratio of non–vitamin K antagonist oral anticoagulant treatment in patients with atrial fibrillation and history of previous intracranial bleeding. Ongoing trials are addressing the usefulness of left atrial appendage occlusion in both primary and secondary stroke prevention for patients with atrial fibrillation, including those with high risk of bleeding. The additive value of prolonged cardiac monitoring for subclinical atrial fibrillation detection through smartphone applications or implantable cardiac devices, together with the optimal medical management of individuals with covert paroxysmal atrial fibrillation, is a topic of intensive research interest. Colchicine treatment and factor XIa inhibition constitute 2 novel pharmacologic approaches that might provide future treatment options in the secondary prevention of cardioembolic stroke attributable to atrial fibrillation.

Clinical management of cerebral small vessel disease: a call for a holistic approach

ABSTRACT

Cerebral small vessel disease (SVD) is a common global brain disease that causes cognitive impairment, ischemic or hemorrhagic stroke, problems with mobility, and neuropsychiatric symptoms. The brain damage, seen as focal white and deep grey matter lesions on brain magnetic resonance imaging (MRI) or computed tomography (CT), typically accumulates "covertly" and may reach an advanced state before being detected incidentally on brain scanning or causing symptoms. Patients have typically presented to different clinical services or been recruited into research focused on one clinical manifestation, perhaps explaining a lack of awareness, until recently, of the full range and complexity of SVD.In this review, we discuss the varied clinical presentations, established and emerging risk factors, relationship to SVD features on MRI or CT, and the current state of knowledge on the effectiveness of a wide range of pharmacological and lifestyle interventions. The core message is that effective assessment and clinical management of patients with SVD, as well as future advances in diagnosis, care, and treatment, will require a more "joined-up"' approach. This approach should integrate clinical expertise in stroke neurology, cognitive, and physical dysfunctions. It requires more clinical trials in order to improve pharmacological interventions, lifestyle and dietary modifications. A deeper understanding of the pathophysiology of SVD is required to steer the identification of novel interventions. An essential prerequisite to accelerating clinical trials is to improve the consistency, and standardization of clinical, cognitive and neuroimaging endpoints.

Multiple versus fewer antiplatelet agents for preventing early recurrence after ischaemic stroke or transient ischaemic attack

BACKGROUND

Stroke is a leading cause of morbidity and mortality worldwide. Antiplatelet agents are considered to be the cornerstone for secondary prevention of stroke, but the role of using multiple antiplatelet agents early after stroke or transient ischaemic attack (TIA) to improve outcomes has not been established.

OBJECTIVES

To determine the effectiveness and safety of initiating, within 72 hours after an ischaemic stroke or TIA, multiple antiplatelet agents versus fewer antiplatelet agents to prevent stroke recurrence. The analysis explores the evidence for different drug combinations.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched 6 July 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 7 of 12, 2020) (last searched 6 July 2020), MEDLINE Ovid (from 1946 to 6 July 2020), Embase (1980 to 6 July 2020), ClinicalTrials.gov, and the WHO ICTRP. We also searched the reference lists of identified studies and reviews and used the Science Citation Index Cited Reference search for forward tracking of included studies.

SELECTION CRITERIA

We selected all randomised controlled trials (RCTs) that compared the use of multiple versus fewer antiplatelet agents initiated within 72 hours after stroke or TIA.

DATA COLLECTION AND ANALYSIS

We extracted data from eligible studies for the primary outcomes of stroke recurrence and vascular death, and secondary outcomes of myocardial infarction; composite outcome of stroke, myocardial infarction, and vascular death; intracranial haemorrhage; extracranial haemorrhage; ischaemic stroke; death from all causes; and haemorrhagic stroke. We computed an estimate of treatment effect and performed a test for heterogeneity between trials. We analysed data on an intention-to-treat basis and assessed bias for all studies. We rated the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 15 RCTs with a total of 17,091 participants. Compared with fewer antiplatelet agents, multiple antiplatelet agents were associated with a significantly lower risk of stroke recurrence (5.78% versus 7.84%, risk ratio (RR) 0.73, 95% confidence interval (CI) 0.66 to 0.82; P < 0.001; moderate-certainty evidence) with no significant difference in vascular death (0.60% versus 0.66%, RR 0.98, 95% CI 0.66 to 1.45; P = 0.94; moderate-certainty evidence). There was a higher risk of intracranial haemorrhage (0.42% versus 0.21%, RR 1.92, 95% CI 1.05 to 3.50; P = 0.03; low-certainty evidence) and extracranial haemorrhage (6.38% versus 2.81%, RR 2.25, 95% CI 1.88 to 2.70; P < 0.001; high-certainty evidence) with multiple antiplatelet agents. On secondary analysis of dual versus single antiplatelet agent therapy, benefit for stroke recurrence (5.73% versus 8.06%, RR 0.71, 95% CI 0.62 to 0.80; P < 0.001; moderate-certainty evidence) was maintained as well as risk of extracranial haemorrhage (1.24% versus 0.40%, RR 3.08, 95% CI 1.74 to 5.46; P < 0.001; high-certainty evidence). The composite outcome of stroke, myocardial infarction, and vascular death (6.37% versus 8.77%, RR 0.72, 95% CI 0.64 to 0.82; P < 0.001; moderate-certainty evidence) and ischaemic stroke (6.30% versus 8.94%, RR 0.70, 95% CI 0.61 to 0.81; P < 0.001; high-certainty evidence) were significantly in favour of dual antiplatelet therapy, whilst the risk of intracranial haemorrhage became less significant (0.34% versus 0.21%, RR 1.53, 95% CI 0.76 to 3.06; P = 0.23; low-certainty evidence).

AUTHORS' CONCLUSIONS

Multiple antiplatelet agents are more effective in reducing stroke recurrence but increase the risk of haemorrhage compared to one antiplatelet agent. The benefit in reduction of stroke recurrence seems to outweigh the harm for dual antiplatelet agents initiated in the acute setting and continued for one month. There is lack of evidence regarding multiple versus multiple antiplatelet agents. Further studies are required in different populations to establish comprehensive safety profiles and long-term outcomes to establish duration of therapy.

A Narrative and Critical Review of Randomized-Controlled Clinical Trials on Patent Foramen Ovale Closure for Reducing the Risk of Stroke Recurrence

Patent foramen ovale (PFO) is a common cardiac anatomic variant that has been increasingly found in young (<60 years) cryptogenic stroke patients. Despite initial neutral randomized-controlled clinical trials (RCTs), there have been four recent RCTs providing consistent data in favor of the efficacy and safety of PFO closure compared to medical therapy for secondary stroke prevention. However, taking into consideration the high prevalence of PFO, the low risk of stroke recurrence under medical treatment and the uncommon yet severe adverse events of the intervention, patient selection is crucial for attaining meaningful clinical benefits. Thorough workup to exclude alternative causes of stroke and identification of high-risk PFOs through clinical, neuroimaging and echocardiographic criteria are essential. Cost effectiveness of the procedure cannot be proven for the time being, since there are no robust data on clinical outcome after PFO-associated stroke but only limited anecdotal data suggesting low risk for long-term disability.

Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis

IMPORTANCE

The benefit of blood pressure lowering for the prevention of dementia or cognitive impairment is unclear.

OBJECTIVE

To determine the association of blood pressure lowering with dementia or cognitive impairment.

DATA SOURCES AND STUDY SELECTION

Search of PubMed, EMBASE, and CENTRAL for randomized clinical trials published from database inception through December 31, 2019, that evaluated the association of blood pressure lowering on cognitive outcomes. The control groups consisted of either placebo, alternative antihypertensive agents, or higher blood pressure targets.

DATA EXTRACTION AND SYNTHESIS

Data were screened and extracted independently by 2 authors. Random-effects meta-analysis models were used to report pooled treatment effects and CIs.

MAIN OUTCOMES AND MEASURES

The primary outcome was dementia or cognitive impairment. The secondary outcomes were cognitive decline and changes in cognitive test scores.

RESULTS

Fourteen randomized clinical trials were eligible for inclusion (96 158 participants), of which 12 reported the incidence of dementia (or composite of dementia and cognitive impairment [3 trials]) on follow-up and were included in the primary meta-analysis, 8 reported cognitive decline, and 8 reported changes in cognitive test scores. The mean (SD) age of trial participants was 69 (5.4) years and 40 617 (42.2%) were women. The mean systolic baseline blood pressure was 154 (14.9) mm Hg and the mean diastolic blood pressure was 83.3 (9.9) mm Hg. The mean duration of follow-up was 49.2 months. Blood pressure lowering with antihypertensive agents compared with control was significantly associated with a reduced risk of dementia or cognitive impairment (12 trials; 92 135 participants) (7.0% vs 7.5% of patients over a mean trial follow-up of 4.1 years; odds ratio [OR], 0.93 [95% CI, 0.88-0.98]; absolute risk reduction, 0.39% [95% CI, 0.09%-0.68%]; I2 = 0.0%) and cognitive decline (8 trials) (20.2% vs 21.1% of participants over a mean trial follow-up of 4.1 years; OR, 0.93 [95% CI, 0.88-0.99]; absolute risk reduction, 0.71% [95% CI, 0.19%-1.2%]; I2 = 36.1%). Blood pressure lowering was not significantly associated with a change in cognitive test scores.

CONCLUSIONS AND RELEVANCE

In this meta-analysis of randomized clinical trials, blood pressure lowering with antihypertensive agents compared with control was significantly associated with a lower risk of incident dementia or cognitive impairment.

Association of Blood Pressure and Cognition after Stroke

BACKGROUND AND AIM

It is unclear whether blood pressure (BP) is associated with cognition after stroke. We examined associations between systolic and diastolic BP (SBP, DBP), pulse pressure (PP), mean arterial pressure (MAP), and cognition, each measured 90 days after stroke.

METHODS

Cross-sectional analysis of prospectively obtained data of 432 dementia-free subjects greater than or equal to 45 (median age, 66; 45% female) with stroke (92% ischemic; median NIH stroke score, 3 [IQR, 2-6]) from the population-based Brain Attack Surveillance in Corpus Christi (BASIC) project in 2011-2013.

PRIMARY OUTCOME

Modified Mini-Mental Status Examination (3MSE; range, 0-100).

SECONDARY OUTCOMES

Animal Fluency Test (AFT; range, 0-10) and Trail Making Tests A and B (number of correct items [range, 0-25]/completion time [Trails A: 0-180 seconds; Trails B: 0-300 second]). Linear or tobit regression adjusted associations for age, education, and race/ethnicity as well as variables significantly associated with BP and cognition.

RESULTS

Higher SBP, lower DBP, higher PP, and lower MAP each were associated with worse cognitive performance for all 4 tests (all P < .001). After adjusting for patient factors, no BP measures were associated with any of the 4 tests (all P > .05). Lower cognitive performance was associated with older age, less education, Mexican American ethnicity, diabetes, higher stroke severity, more depressive symptoms, and lower BMI. Among survivors with hypertension, anti-hypertensive medication use 90 days after stroke was significantly associated with higher AFT scores (P = .02) but not other tests (P > .15).

CONCLUSIONS

Stroke survivors' BP levels were not associated with cognitive performance at 90 days independent of sociodemographic and clinical factors.

Protocol: The Lacunar Intervention Trial 2 (LACI-2). A trial of two repurposed licenced drugs to prevent progression of cerebral small vessel disease

Background

Small vessel disease causes a quarter of ischaemic strokes (lacunar subtype), up to 45% of dementia either as vascular or mixed types, cognitive impairment and physical frailty. However, there is no specific treatment to prevent progression of small vessel disease.

Aim

We designed the LACunar Intervention Trial-2 (LACI-2) to test feasibility of a large trial testing cilostazol and/or isosorbide mononitrate (ISMN) by demonstrating adequate participant recruitment and retention in follow-up, drug tolerability, safety and confirm outcome event rates required to power a phase 3 trial.

Methods and design

LACI-2 is an investigator-initiated, prospective randomised open label blinded endpoint (PROBE) trial aiming to recruit 400 patients with prior lacunar syndrome due to a small subcortical infarct. We randomise participants to cilostazol v no cilostazol and ISMN or no ISMN, minimising on key prognostic factors. All patients receive guideline-based best medical therapy. Patients commence trial drug at low dose, increment to full dose over 2–4 weeks, continuing on full dose for a year. We follow-up participants to one year for symptoms, tablet compliance, safety, recurrent vascular events, cognition and functional outcomes, Trails B and brain MRI. LACI-2 is registered ISRCTN 14911850, EudraCT 2016–002277-35.

Trial outcome: Primary outcome is feasibility of recruitment and compliance; secondary outcomes include safety (cerebral or systemic bleeding, falls, death), efficacy (recurrent cerebral and cardiac vascular events, cognition on TICS, Trails B) and tolerability.

Summary

LACI-2 will determine feasibility, tolerability and provide outcome rates to power a large phase 3 trial to prevent progression of cerebral small vessel disease.

Neuropsychological assessment of mild cognitive impairment in Latinx adults: A scoping review

Objective: Latinx populations are rapidly growing and aging in the United States. There is a critical need to accurately and efficiently detect those at risk for dementia, particularly those with mild cognitive impairment (MCI). MCI diagnosis often relies on neuropsychological assessment, although cultural, demographic, and linguistic characteristics may impact test scores. This study provides a scoping review of neuropsychological studies on MCI in Hispanic/Latinx populations to evaluate how studies report and account for these factors in diagnosis of MCI. Method: Studies were identified using Web of Science, PubMed, and Scopus, using search terms (Hispanic* OR Latin* OR "Mexican American*" OR "Puerto Ric*" OR Caribbean) and ("Mild Cognitive Impairment" OR MCI). Studies using neuropsychological tests in diagnosis of MCI for Latinx individuals in the United States were identified. Sample characterization (e.g., country of origin, literacy, language preference and proficiency), neuropsychological testing methods (e.g., test selection and translation, normative data source), and method of MCI diagnosis were reviewed. Results: Forty-four articles met inclusion criteria. There was considerable variability in reporting of demographic, cultural and linguistic factors across studies of MCI in Latinx individuals. For example, only 5% of studies reported nativity status, 52% reported information on language preference and use, and 34% reported the method and/or source of test translation and adaptation. Conclusions: Future studies of diagnosis of MCI in Latinx individuals should report cultural details and use of appropriate neuropsychological assessment tools and normative data. This is important to accurately estimate the prevalence of MCI in Latinx individuals. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Simple MRI score aids prediction of dementia in cerebral small vessel disease

Objective

To determine whether a simple small vessel disease (SVD) score, which uses information available on rapid visual assessment of clinical MRI scans, predicts risk of cognitive decline and dementia, above that provided by simple clinical measures.

Methods

Three prospective longitudinal cohort studies (SCANS [St George's Cognition and Neuroimaging in Stroke], RUN DMC [Radboud University Nijmegen Diffusion Imaging and Magnetic Resonance Imaging Cohort], and the ASPS [Austrian Stroke Prevention Study]), which covered a range of SVD severity from mild and asymptomatic to severe and symptomatic, were included. In all studies, MRI was performed at baseline, cognitive tests repeated during follow-up, and progression to dementia recorded prospectively. Outcome measures were cognitive decline and onset of dementia during follow-up. We determined whether the SVD score predicted risk of cognitive decline and future dementia. We also determined whether using the score to select a group of patients with more severe disease would reduce sample sizes for clinical intervention trials.

Results

In a pooled analysis of all 3 cohorts, the score improved prediction of dementia (area under the curve [AUC], 0.85; 95% confidence interval [CI], 0.81–0.89) compared with that from clinical risk factors alone (AUC, 0.76; 95% CI, 0.71–0.81). Predictive performance was higher in patients with more severe SVD. Power calculations showed selecting patients with a higher score reduced sample sizes required for hypothetical clinical trials by 40%–66% depending on the outcome measure used.

Conclusions

A simple SVD score, easily obtainable from clinical MRI scans and therefore applicable in routine clinical practice, aided prediction of future dementia risk.

[White matter hyperintensities in ageing: Pathophysiology, associated cognitive disorders and prevention]

White matter hyperintensities (WMH), also known as leukoaraïosis are very common neuroradiological manifestations in the elderly. The main risk factors for WMH are age and high blood pressure. The vascular origin of these lesions is classically accepted and WMH are considered as one feature of the small vessel disease. WMH may be associated with clinical symptoms, depending notably on their importance according to age. They are associated with increased mortality, strokes and changes in cognition with a higher risk of dementia (vascular dementia or Alzheimer's disease). Modification of vascular risk factors could have a beneficial effect, but few evidences from controlled trials are available.

The Whole Picture: From Isolated to Global MRI Measures of Neurovascular and Neurodegenerative Disease

Structural magnetic resonance imaging (MRI) has been used to characterise the appearance of the brain in cerebral small vessel disease (SVD), ischaemic stroke, cognitive impairment, and dementia. SVD is a major cause of stroke and dementia; features of SVD include white matter hyperintensities (WMH) of presumed vascular origin, lacunes of presumed vascular origin, microbleeds, and perivascular spaces. Cognitive impairment and dementia have traditionally been stratified into subtypes of varying origin, e.g., vascular dementia versus dementia of the Alzheimer's type (Alzheimer's disease; AD). Vascular dementia is caused by reduced blood flow in the brain, often as a result of SVD, and AD is thought to have its genesis in the accumulation of tau and amyloid-beta leading to brain atrophy. But after early seminal studies in the 1990s found neurovascular disease features in around 30% of AD patients, it is becoming recognised that so-called "mixed pathologies" (of vascular and neurodegenerative origin) exist in many more patients diagnosed with stroke, only one type of dementia, or cognitive impairment. On the back of these discoveries, attempts have recently been made to quantify the full extent of degenerative and vascular disease in the brain in vivo on MRI. The hope being that these "global" methods may one day lead to better diagnoses of disease and provide more sensitive measurements to detect treatment effects in clinical trials. Indeed, the "Total MRI burden of cerebral small vessel disease", the "Brain Health Index" (BHI), and "MRI measure of degenerative and cerebrovascular pathology in Alzheimer disease" have all been shown to have stronger associations with clinical and cognitive phenotypes than individual brain MRI features. This chapter will review individual structural brain MRI features commonly seen in SVD, stroke, and dementia. The relationship between these features and differing clinical and cognitive phenotypes will be discussed along with developments in their measurement and quantification. The chapter will go on to review emerging methods for quantifying the collective burden of structural brain MRI findings and how these "whole picture" methods may lead to better diagnoses of neurovascular and neurodegenerative disorders.

Vascular Cognitive Impairment

PURPOSE OF REVIEW

This article provides an overview of vascular cognitive impairment; discusses its epidemiology, subtypes, and associations with other neurodegenerative diseases; and reviews the diagnostic evaluation and management of these disorders.

RECENT FINDINGS

Cerebrovascular disease is a common cause of dementia and frequently coexists with neurodegenerative causes. The heterogeneity of mechanisms leading to vascular cognitive impairment makes developing unifying clinical and research criteria difficult. Recognizing the neuroimaging hallmarks of different forms of vascular cognitive impairment can allow for individualized treatment and management. In individuals with mild vascular cognitive impairment, aerobic exercise appears to be a promising treatment but requires further investigation.

SUMMARY

Vascular cognitive impairment can be caused by several mechanisms. While treating vascular risk factors is rational to prevent worsening of cognitive impairment, well-designed studies are needed to demonstrate efficacy.