Incidence of Brain Infarcts, Cognitive Change, and Risk of Dementia in the General Population: The AGES-Reykjavik Study (Age Gene/Environment Susceptibility-Reykjavik Study)

Incident Infarcts in Patients With Stroke and Cerebral Small Vessel Disease: Frequency and Relation to Clinical Outcomes

BACKGROUND AND OBJECTIVES

Factors associated with cerebral small vessel disease (SVD) progression, including incident infarcts, are unclear. We aimed to determine the frequency of incident infarcts over 1 year after minor stroke and their relation to baseline SVD burden, vascular risks, and recurrent stroke and cognitive outcomes.

METHODS

We recruited patients with lacunar or nondisabling cortical stroke. After diagnostic imaging, we repeated structural MRI at 3-6 monthly intervals for 12 months, visually assessing incident infarcts on diffusion-weighted imaging or FLAIR. We used logistic regression to determine associations of baseline vascular risks, SVD score, and index stroke subtype with subsequent incident infarcts. We assessed cognitive and functional outcomes at 1 year using Montreal Cognitive Assessment (MoCA) and modified Rankin scale (mRS), adjusting for baseline age, mRS, MoCA, premorbid intelligence, and SVD score.

RESULTS

We recruited 229 participants, mean age 65.9 (SD 11.1). Over half of all participants, 131 of 229 (57.2%) had had an index lacunar stroke. From baseline to 1-year MRI, we detected 117 incident infarcts in n = 57/229 (24.8%) participants. Incident infarcts were mainly of the small subcortical (86/117 [73.5%] in n = 38/57 [66.7%]) vs cortical infarct subtype (n = 19/57 [33.3%]). N = 39/57 participants had incident infarcts at 1 visit; 18 of 57 at 2 or more visits; and 19 of 57 participants had multiple infarcts at a single visit. Only 7 of 117 incident infarcts corresponded temporally to clinical stroke syndromes. The baseline SVD score was the strongest predictor of incident infarcts (adjusted odds ratio [OR] 1.87, 95% CI 1.39-2.58), while mean arterial pressure was not associated. All participants with incident infarcts were prescribed an antiplatelet or anticoagulant. Lower 1-year MoCA was associated with lower baseline MoCA (β 0.47, 95% CI 0.33-0.61), lower premorbid intelligence, and older age. Higher 1-year mRS was associated with higher baseline mRS only (OR 5.57 [3.52-9.10]). Neither outcome was associated with incident infarcts.

DISCUSSION

In the year after stroke in a population enriched for lacunar stroke, incident infarcts occurred in one-quarter and were associated with worse baseline SVD. Most incident infarcts detected on imaging did not correspond to clinical stroke/transient ischemic attack. Worse 1-year cognition and function were not associated with incident infarcts.

Cerebral arteriolosclerosis, lacunar infarcts, and cognition in older Black adults

INTRODUCTION

Older Black adults are at risk of cerebral small vessel disease (CSVD), which contributes to dementia risk. Two subtypes of CSVD, arteriolosclerosis and ischemic lacunar infarcts, have been independently linked to lower cognition and higher dementia risk, but their combined effects on cognition in older Black adults are unclear.

METHODS

Mixed models were used to examine the associations of in vivo measures of arteriolosclerosis (ARTS) and ischemic lacunar infarcts to cognitive level and change in 370 older Black adults without dementia.  RESULTS: Modeled together, higher ARTS load accounted for lower levels of global cognition, episodic memory, semantic memory, and perceptual speed, whereas higher infarct load accounted for lower levels of working memory. There were no associations with rate of cognitive change.

DISCUSSION

Both arteriolosclerosis and ischemic infarcts impact the cognitive health of older Black adults, but arteriolosclerosis affects cognition more broadly and offers promise as an in vivo biomarker of dementia risk.

HIGHLIGHTS

Older Black adults are at risk of cerebral small vessel disease (CSVD) and dementia. Examined magnetic resonance imaging-derived measure of arteriolosclerosis (ARTS), infarcts, and cognition. ARTS load was widely associated with lower cognition after adjusting for infarct load. Infarct load was specifically associated with lower complex attention. More within-Black in vivo studies of CSVD subtypes and cognition are needed.

Vascular cognitive impairment: Advances in clinical research and management

ABSTRACT

Vascular cognitive impairment (VCI) encompasses a wide spectrum of cognitive disorders, ranging from mild cognitive impairment to vascular dementia. Its diagnosis relies on thorough clinical evaluations and neuroimaging. VCI predominately arises from vascular risk factors (VRFs) and cerebrovascular disease, either independently or in conjunction with neurodegeneration. Growing evidence underscores the prevalence of VRFs, highlighting their potential for early prediction of cognitive impairment and dementia in later life. The precise mechanisms linking vascular pathologies to cognitive deficits remain elusive. Chronic cerebrovascular pathology is the most common neuropathological feature of VCI, often interacting synergistically with neurodegenerative processes. Current research efforts are focused on developing and validating reliable biomarkers to unravel the etiology of vascular brain changes in VCI. The collaborative integration of these biomarkers into clinical practice, alongside routine incorporation into neuropathological assessments, presents a promising strategy for predicting and stratifying VCI. The cornerstone of VCI prevention remains the control of VRFs, which includes multi-domain lifestyle modifications. Identifying appropriate pharmacological approaches is also of paramount importance. In this review, we synthesize recent advancements in the field of VCI, including its definition, determinants of vascular risk, pathophysiology, neuroimaging and fluid-correlated biomarkers, predictive methodologies, and current intervention strategies. Increasingly evident is the notion that more rigorous research for VCI, which arises from a complex interplay of physiological events, is still needed to pave the way for better clinical outcomes and enhanced quality of life for affected individuals.

Proteomic analysis of Alzheimer's disease cerebrospinal fluid reveals alterations associated with APOE ε4 and atomoxetine treatment

Alzheimer's disease (AD) is currently defined by the aggregation of amyloid-β (Aβ) and tau proteins in the brain. Although biofluid biomarkers are available to measure Aβ and tau pathology, few markers are available to measure the complex pathophysiology that is associated with these two cardinal neuropathologies. Here, we characterized the proteomic landscape of cerebrospinal fluid (CSF) changes associated with Aβ and tau pathology in 300 individuals using two different proteomic technologies-tandem mass tag mass spectrometry and SomaScan. Integration of both data types allowed for generation of a robust protein coexpression network consisting of 34 modules derived from 5242 protein measurements, including disease-relevant modules associated with autophagy, ubiquitination, endocytosis, and glycolysis. Three modules strongly associated with the apolipoprotein E ε4 (APOE ε4) AD risk genotype mapped to oxidant detoxification, mitogen-associated protein kinase signaling, neddylation, and mitochondrial biology and overlapped with a previously described lipoprotein module in serum. Alterations of all three modules in blood were associated with dementia more than 20 years before diagnosis. Analysis of CSF samples from an AD phase 2 clinical trial of atomoxetine (ATX) demonstrated that abnormal elevations in the glycolysis CSF module-the network module most strongly correlated to cognitive function-were reduced by ATX treatment. Clustering of individuals based on their CSF proteomic profiles revealed heterogeneity of pathological changes not fully reflected by Aβ and tau.

Atrial Fibrillation and Dementia: Pathophysiological Mechanisms and Clinical Implications

Numerous longitudinal studies suggest a strong association between cardiovascular risk factors and cognitive impairment. Individuals with atrial fibrillation are at higher risk of dementia and cognitive dysfunction, as atrial fibrillation increases the risk of cerebral hypoperfusion, inflammation, and stroke. The lack of comprehensive understanding of the observed association and the complex relationship between these two diseases makes it very hard to provide robust guidelines on therapeutic indications. With this review, we attempt to shed some light on how atrial fibrillation is related to dementia, what we know regarding preventive interventions, and how we could move forward in managing those very frequently overlapping conditions.

Imaging Biomarkers of VCI: A Focused Update

Vascular cognitive impairment is common after stroke, in memory clinics, medicine for the elderly services, and undiagnosed in the community. Vascular disease is said to be the second most common cause of dementia after Alzheimer disease, yet vascular dysfunction is now known to predate cognitive decline in Alzheimer disease, and most dementias at older ages are mixed. Neuroimaging has a major role in identifying the proportion of vascular versus other likely pathologies in patients with cognitive impairment. Here, we aim to provide a pragmatic but evidence-based summary of the current state of potential imaging biomarkers, focusing on magnetic resonance imaging and computed tomography, which are relevant to diagnosing, estimating prognosis, monitoring vascular cognitive impairment, and incorporating our own experiences. We focus on markers that are well-established, with a known profile of association with cognitive measures, but also consider more recently described, including quantitative tissue markers of vascular injury. We highlight the gaps in accessibility and translation to more routine clinical practice.

Bibliometric Insights Into the Evolution of Atrial Fibrillation and Dementia Research 2002-2022

BACKGROUND In response to the escalating prevalence of atrial fibrillation (AF) and its potential correlation with cognitive impairment and dementia, we conducted a comprehensive bibliometric analysis to assess current research trends, contributors, and collaborative networks in this evolving interdisciplinary field. MATERIAL AND METHODS Articles published between 2002 and 2022 were extracted from the Web of Science database and carefully screened, yielding 328 publications. Two reviewers independently conducted the screening and quality appraisal. We employed sophisticated tools such as CiteSpace, VOSviewer, and Bibliometrix (R-Studio's R tool) to succinctly summarize and thoroughly analyze the publications. RESULTS A total of 328 publications, comprising 262 papers and 66 reviews, were included in the final analysis. The number of publications exhibited a consistent year-on-year increase, demonstrating an average annual growth rate of 20.57%. These publications originated from 41 countries and regions, with the highest contributions observed from the United States, United Kingdom, Italy, and China. Notably, the University of Liverpool emerged as the most prolific institution, while the most prolific author was Lip GYH from the United Kingdom. The journal with the most publications is the journal of the American Heart Association (19 articles). The most popular keywords in order were: risk and stroke (n=101), dementia (n=100), decline (n=70), prevalence (n=67), and Alzheimer's disease. CONCLUSIONS This study shows the current research status and emerging trends in atrial fibrillation's link to dementia and cognitive impairment. It highlights global growth and collaboration patterns while offering a comprehensive view of their interrelationship, pointing toward future research directions.

Modified Constraint-Induced Movement Therapy for Improving Balance and Gait in a Case of Ganglio-Capsular Infarct: A Single-Case Study

The ganglio-capsular region consists of the basal ganglia nuclei (caudate nucleus and lentiform nucleus), thalamus, and internal capsule. A disorder of the ganglio-capsular region typically presents with movement disturbance and cognitive impairment. This report presents the case of a 52-year-old male who was diagnosed with acute non-hemorrhagic infarct in the right parietal-occipital-temporal region predominantly involving the cortex and in the right ganglio-capsular region. The patient exhibited typical symptoms, which include impaired reflexes, decreased strength, reduced range of motion, and tone abnormalities. Targeted early physiotherapy intervention (TERI) was initiated from the bedside in the intensive care unit (ICU). Modified constraint-induced movement therapy (mCIMT) along with conventional therapy was selected as the rehabilitation approach for the case as it deals with "forced use" of the affected extremities, which addresses "learned non-use." The case was managed for a duration of six weeks, in which clinical outcomes, including the Berg Balance Scale (BBS), 10-meter walk test (10MWT), functional reach test (FRT), dynamic gait index (DGI), trunk impairment scale (TIS), and fall efficacy test (FET), reported crucial changes in balance, strength, coordination, and tone, which improved the quality of life of the patient.

Association Between Small Vessel Disease and Financial Capacity: A Study Based on Cognitively Normal Older Adults

Background

Financial capacity is vital for the elderly, who possess a substantial share of global wealth but are vulnerable to financial fraud.

Objective

We explored the link between small vessel disease (SVD) and financial capacity in cognitively unimpaired (CU) older adults via both cross-sectional and longitudinal analyses.

Methods

414 CU participants underwent MRI and completed the Financial Capacity Instrument-Short Form (FCI-SF). Subsequent longitudinal FCI-SF data were obtained from 104, 240, and 141 participants at one, two, and four years, respectively. SVD imaging markers, encompassing white matter hyperintensities (WMH), cerebral microbleeds (CMB), and lacune were evaluated. We used linear regression analyses to cross-sectionally explore the association between FCI-SF and SVD severity, and linear mixed models to assess how baseline SVD severity impacted longitudinal FCI-SF change. The false discovery rate method was used to adjust multiple comparisons.

Results

Cross-sectional analysis revealed a significant association between baseline WMH and Bank Statement (BANK, β=-0.194), as well as between lacune number and Financial Conceptual Knowledge (FC, β= -0.171). These associations were stronger in APOE ɛ4 carriers, with β= -0.282 for WMH and BANK, and β= -0.366 for lacune number and FC. Longitudinally, higher baseline SVD total score was associated with severe FCI-SF total score decrease (β= -0.335). Additionally, baseline WMH burden predicted future decreases in Single Checkbook/Register Task (SNG, β= -0.137) and FC (β= -0.052). Notably, the association between baseline WMH and SNG changes was amplified in APOE ɛ4 carriers (β= -0.187).

Conclusions

Severe SVD was associated with worse FCI-SF and could predict the decline of financial capacity in CU older adults.

Changes in Cognitive Functions after Carotid Endarterectomy and Carotid Stenting: A Decade-Apart Comparison

BACKGROUND

This study investigates changes in cognitive function in patients with severe carotid stenosis who underwent carotid endarterectomy (CEA) and carotid stenting (CAS) over two decades.

METHODS

We compared cognitive function within 30 days after the procedure in 267 patients (first 100 each for CEA and CAS in two periods: 2008-2012 and 2018-2022) in a single institution. Assessments used Adenbrooke's Cognitive Examination-Revised (ACE-R), the Mini-Mental State Examination (MMSE), Speech Fluency Test (SFT), and Clock Drawing Test (CDT), conducted before and 30 ± 2 days after surgery.

RESULTS

Patients (mean age 67.2 years, 70%+ carotid stenosis) exhibited different cognitive changes over periods. In 2008-2012, significant declines in MMSE (CEA, p = 0.049) and CDT (CAS, p = 0.015) were observed among asymptomatic patients. On the contrary, in 2018-2022, improvements were observed in ACE-R and MMSE for symptomatic and asymptomatic patients undergoing CEA and CAS.

CONCLUSION

Over a decade, advances in interventional techniques and patient management have reduced risks of cognitive decline in patients with asymptomatic carotid stenosis and also have improved cognitive functions in both symptomatic and asymptomatic individuals.

Serum proteomics reveals APOE dependent and independent protein signatures in Alzheimer's disease

The current demand for early intervention, prevention, and treatment of late onset Alzheimer's disease (LOAD) warrants deeper understanding of the underlying molecular processes which could contribute to biomarker and drug target discovery. Utilizing high-throughput proteomic measurements in serum from a prospective population-based cohort of older adults (n=5,294), we identified 303 unique proteins associated with incident LOAD (median follow-up 12.8 years). Over 40% of these proteins were associated with LOAD independently of APOE-ε4 carrier status. These proteins were implicated in neuronal processes and overlapped with protein signatures of LOAD in brain and cerebrospinal fluid. We found 17 proteins which LOAD-association was strongly dependent on APOE-ε4 carrier status. Most of them showed consistent associations with LOAD in cerebrospinal fluid and a third had brain-specific gene expression. Remarkably, four proteins in this group (TBCA, ARL2, S100A13 and IRF6) were downregulated by APOE-ε4 yet upregulated as a consequence of LOAD as determined in a bi-directional Mendelian randomization analysis, reflecting a potential response to the disease onset. Accordingly, the direct association of these proteins to LOAD was reversed upon APOE-ε4 genotype adjustment, a finding which we replicate in an external cohort (n=719). Our findings provide an insight into the dysregulated pathways that may lead to the development and early detection of LOAD, including those both independent and dependent on APOE-ε4. Importantly, many of the LOAD-associated proteins we find in the circulation have been found to be expressed - and have a direct link with AD - in brain tissue. Thus, the proteins identified here, and their upstream modulating pathways, provide a new source of circulating biomarker and therapeutic target candidates for LOAD.

Proteomic Network Analysis of Alzheimer's Disease Cerebrospinal Fluid Reveals Alterations Associated with APOE ε4 Genotype and Atomoxetine Treatment

Alzheimer's disease (AD) is currently defined at the research level by the aggregation of amyloid-β (Aβ) and tau proteins in brain. While biofluid biomarkers are available to measure Aβ and tau pathology, few biomarkers are available to measure the complex pathophysiology that is associated with these two cardinal neuropathologies. Here we describe the proteomic landscape of cerebrospinal fluid (CSF) changes associated with Aβ and tau pathology in 300 individuals as assessed by two different proteomic technologies-tandem mass tag (TMT) mass spectrometry and SomaScan. Harmonization and integration of both data types allowed for generation of a robust protein co-expression network consisting of 34 modules derived from 5242 protein measurements, including disease-relevant modules associated with autophagy, ubiquitination, endocytosis, and glycolysis. Three modules strongly associated with the apolipoprotein E ε4 (APOE ε4) AD risk genotype mapped to oxidant detoxification, mitogen associated protein kinase (MAPK) signaling, neddylation, and mitochondrial biology, and overlapped with a previously described lipoprotein module in serum. Neddylation and oxidant detoxification/MAPK signaling modules had a negative association with APOE ε4 whereas the mitochondrion module had a positive association with APOE ε4. The directions of association were consistent between CSF and blood in two independent longitudinal cohorts, and altered levels of all three modules in blood were associated with dementia over 20 years prior to diagnosis. Dual-proteomic platform analysis of CSF samples from an AD phase 2 clinical trial of atomoxetine (ATX) demonstrated that abnormal elevations in the glycolysis CSF module-the network module most strongly correlated to cognitive function-were reduced by ATX treatment. Individuals who had more severe glycolytic changes at baseline responded better to ATX. Clustering of individuals based on their CSF proteomic network profiles revealed ten groups that did not cleanly stratify by Aβ and tau status, underscoring the heterogeneity of pathological changes not fully reflected by Aβ and tau. AD biofluid proteomics holds promise for the development of biomarkers that reflect diverse pathologies for use in clinical trials and precision medicine.

Cardiovascular Disease and Stroke in Immune TTP-Challenges and Opportunities

Advances in the management of immune thrombotic thrombocytopenic purpura (iTTP) have dramatically improved outcomes of acute TTP episodes, and TTP is now treated as a chronic, relapsing disorder. It is now recognized that iTTP survivors are at high risk for vascular disease, with stroke and myocardial infarction occurring at younger ages than in the general population, and cardiovascular disease is the leading cause of premature death in this population. iTTP appears to have a phenotype of accelerated vascular aging with a particular predilection for cerebral circulation, and stroke is much more common than myocardial infarction. In addition to traditional cardiovascular risk factors, low ADAMTS13 activity during clinical remission may be a risk factor for some of these outcomes, such as stroke. Recent studies also suggest that Black patients, who are disproportionately affected by iTTP in the United States, are at higher risk of adverse cardiovascular outcomes, likely due to multifactorial reasons. Additional research is required to establish the risk factors and mechanisms underlying these complications in order to institute optimal screening strategies and identify interventions to improve outcomes.

Dementia prediction in the general population using clinically accessible variables: a proof-of-concept study using machine learning. The AGES-Reykjavik study

BACKGROUND

Early identification of dementia is crucial for prompt intervention for high-risk individuals in the general population. External validation studies on prognostic models for dementia have highlighted the need for updated models. The use of machine learning in dementia prediction is in its infancy and may improve predictive performance. The current study aimed to explore the difference in performance of machine learning algorithms compared to traditional statistical techniques, such as logistic and Cox regression, for prediction of all-cause dementia. Our secondary aim was to assess the feasibility of only using clinically accessible predictors rather than MRI predictors.

METHODS

Data are from 4,793 participants in the population-based AGES-Reykjavik Study without dementia or mild cognitive impairment at baseline (mean age: 76 years, % female: 59%). Cognitive, biometric, and MRI assessments (total: 59 variables) were collected at baseline, with follow-up of incident dementia diagnoses for a maximum of 12 years. Machine learning algorithms included elastic net regression, random forest, support vector machine, and elastic net Cox regression. Traditional statistical methods for comparison were logistic and Cox regression. Model 1 was fit using all variables and model 2 was after feature selection using the Boruta package. A third model explored performance when leaving out neuroimaging markers (clinically accessible model). Ten-fold cross-validation, repeated ten times, was implemented during training. Upsampling was used to account for imbalanced data. Tuning parameters were optimized for recalibration automatically using the caret package in R.

RESULTS

19% of participants developed all-cause dementia. Machine learning algorithms were comparable in performance to logistic regression in all three models. However, a slight added performance was observed in the elastic net Cox regression in the third model (c = 0.78, 95% CI: 0.78-0.78) compared to the traditional Cox regression (c = 0.75, 95% CI: 0.74-0.77).

CONCLUSIONS

Supervised machine learning only showed added benefit when using survival techniques. Removing MRI markers did not significantly worsen our model's performance. Further, we presented the use of a nomogram using machine learning methods, showing transportability for the use of machine learning models in clinical practice. External validation is needed to assess the use of this model in other populations. Identifying high-risk individuals will amplify prevention efforts and selection for clinical trials.

Association of change in cardiovascular risk factors with incident dementia

INTRODUCTION

We evaluated whether better cardiovascular health at midlife and improvement of cardiovascular health within midlife were associated with dementia risk.

METHODS

Two longitudinal population-based studies were used: Atherosclerosis Risk in Communities (ARIC) (n = 11,460/visits at ages 54 and 60), and Age, Gene/Environment Susceptibility (AGES)-Reykjavik (n = 3907/visit at age 51). A cardiovascular health score (range 0-12/0-14, depending on diet availability) including six/seven items was calculated at each visit, with weight assigned to each item as poor (0), intermediate (1), or ideal (2). Cardiovascular health was defined as low (score 0-4/0-5), intermediate (5-7/6-9), or high (8-12/10-14). Incident dementia was ascertained through linkage to health records and with neuropsychological examinations.

RESULTS

Midlife high compared to low cardiovascular health (hazard ratios [HRs]: for ARIC: 0.60 [95% confidence interval: 0.52, 0.69]); for AGES-Reykjavik: 0.83 [0.66, 0.99] and improvement of cardiovascular health score within midlife (HR per one-point increase: ARIC: 0.94 [0.92, 0.96]) were associated with lower dementia risk.

DISCUSSION

Better cardiovascular health at midlife and improvement of cardiovascular health within midlife are associated with lower dementia risk.

HIGHLIGHTS

Cardiovascular health and dementia were studied in two large cohort studies. Better cardiovascular health at midlife relates to lower dementia risk. Improvement of cardiovascular health within midlife relates to lower dementia risk. Promotion of cardiovascular health at midlife can help to reduce dementia risk.

The impact of stroke on the ability to live an independent life at old age: a community-based cohort study of Swedish men

INTRODUCTION

Few studies with controls from the same cohort have investigated the impact of stroke on the ability to live an independent life at old age. We aimed to analyze how great an impact being a stroke survivor would have on cognition and disability. We also analyzed the predictive value of baseline cardiovascular risk factors.

METHODS

We included 1147 men, free from stroke, dementia, and disability, from the Uppsala Longitudinal Study of Adult Men, between 69-74 years of age. Follow-up data were collected between the ages of 85-89 years and were available for 481 of all 509 survivors. Data on stroke diagnosis were obtained through national registries. Dementia was diagnosed through a systematic review of medical charts and in accordance with the current diagnostic criteria. The primary outcome, preserved functions, was a composite outcome comprising four criteria: no dementia, independent in personal activities of daily living, ability to walk outside unassisted, and not living in an institution.

RESULTS

Among 481 survivors with outcome data, 64 (13%) suffered a stroke during the follow-up. Only 31% of stroke cases, compared to 72% of non-stroke cases (adjusted OR 0.20 [95% CI 0.11-0.37]), had preserved functions. The chance of being free of dementia was 60% lower in the stroke group, OR 0.40 [95% CI 0.22-0.72]. No cardiovascular risk factors were independently able to predict preserved functions among stroke cases.

CONCLUSION

Stroke has long lasting consequences for many aspects of disability at very high age.

Iatrogenic Strokes and Covert Brain Infarcts After Percutaneous Cardiac Procedures: An Update

Millions of cardiac procedures are performed worldwide each year, making the potential complication of periprocedural iatrogenic stroke an important concern. These strokes can occur intraoperatively or within 30 days of a procedure and can be categorised as either overt or covert, occurring without obvious acute neurologic symptoms. Understanding the prevalence, risk factors, and strategies for preventing overt and covert strokes associated with cardiac procedures is imperative for reducing periprocedural morbidity and mortality. In this narrative review, we focus on the impacts of perioperative ischemic strokes for several of the most common interventional cardiac procedures, their relevance from a neurologic standpoint, and future directions for the care and research on perioperative strokes. Depending on the percutaneous procedure, the rates of periprocedural overt strokes can range from as little as 0.01% to as high as 2.9%. Meanwhile, covert brain infarctions (CBIs) occur much more frequently, with rates for different procedures ranging from 10%-84%. Risk factors include previous stroke, atherosclerotic disease, carotid stenosis, female sex, and African race, as well as other patient- and procedure-level factors. While the impact of covert brain infarctions is still a developing field, overt strokes for cardiac procedures lead to longer stays in hospital and increased costs. Potential preventative measures include screening and vascular risk factor control, premedicating, and procedural considerations such as the use of cerebral embolic protection devices. In addition, emerging treatments from the neurologic field, including neuroprotective drugs and remote ischemic conditioning, present promising avenues for preventing these strokes and merit investigation in cardiac procedures.

Late-life depression, allostatic load, and risk of dementia: The AGES-Reykjavik study

BACKGROUND

The current study aimed to assess if the relation between depression and dementia could be explained by allostatic load (AL) profiles, as well as assessing their risk on incident all-cause dementia, Alzheimer's disease (AD), and non-AD dementias.

METHODS

The study included individuals without dementia at baseline from the population-based AGES-Reykjavik Study. Depressive symptoms assessed with the Geriatric Depression Scale-15 and AL markers were collected at baseline. Latent profile analysis (LPA) was performed on the AL markers. Incident dementia was measured during 12-years of follow-up. Cox regressions adjusted for AL profiles were performed to evaluate if AL could explain the relation between depressive symptoms and incident dementia. Additional Cox regressions exploring the interaction with depressive symptoms and AL profiles were also performed.

RESULTS

LPA revealed four profiles based on AL factors: 'Low cardiovascular dysregulation' (43 %), 'Average' (42 % prevalence), 'High cardiovascular dysregulation' (11 %), and 'Multisystem dysregulation' (4 %). Cox regression analyses found an increased risk for dementia in the 'Multisystem dysregulation' group (HR 1.72; 95 % CI 1.26-2.33), as well as for AD (HR 1.75; 95 % CI: 1.12-2.71) and non-AD dementias (HR 1.87; 95 % CI: 1.23-2.84). AL profiles did not mediate the risk of all-cause dementia with depressive symptoms; however, there was evidence of additive interaction with depressive symptoms and the 'Multisystem dysregulation' profile and all-cause dementia (RERI 0.15; 95 % CI 0.03-0.26).

CONCLUSION

AL profiles and depressive symptoms were independently related to dementia. Individuals with multisystem dysregulation could be more susceptible to the negative effects of depressive symptomology on incident dementia.

Postoperative delirium is associated with grey matter brain volume loss

Delirium is associated with long-term cognitive dysfunction and with increased brain atrophy. However, it is unclear whether these problems result from or predisposes to delirium. We aimed to investigate preoperative to postoperative brain changes, as well as the role of delirium in these changes over time. We investigated the effects of surgery and postoperative delirium with brain MRIs made before and 3 months after major elective surgery in 299 elderly patients, and an MRI with a 3 months follow-up MRI in 48 non-surgical control participants. To study the effects of surgery and delirium, we compared brain volumes, white matter hyperintensities and brain infarcts between baseline and follow-up MRIs, using multiple regression analyses adjusting for possible confounders. Within the patients group, 37 persons (12%) developed postoperative delirium. Surgical patients showed a greater decrease in grey matter volume than non-surgical control participants [linear regression: B (95% confidence interval) = -0.65% of intracranial volume (-1.01 to -0.29, P < 0.005)]. Within the surgery group, delirium was associated with a greater decrease in grey matter volume [B (95% confidence interval): -0.44% of intracranial volume (-0.82 to -0.06, P = 0.02)]. Furthermore, within the patients, delirium was associated with a non-significantly increased risk of a new postoperative brain infarct [logistic regression: odds ratio (95% confidence interval): 2.8 (0.7-11.1), P = 0.14]. Our study was the first to investigate the association between delirium and preoperative to postoperative brain volume changes, suggesting that delirium is associated with increased progression of grey matter volume loss.

Immune thrombotic thrombocytopenic purpura: Spotlight on long-term outcomes and survivorship

Advances in diagnosis and treatment have dramatically improved survival of acute immune thrombotic thrombocytopenic purpura (iTTP) and iTTP has evolved from an acute fatal condition to a chronic relapsing disorder. In addition to the risk of iTTP relapse, iTTP survivors are at risk of multiple adverse health outcomes including higher than expected rates of all-cause mortality, increased rates of stroke and other cardiovascular disease, and higher rates of morbidities such as obesity, hypertension, and autoimmune disorders. iTTP survivors also report neurocognitive impairment, depression, and reduced quality of life. Women with iTTP are at risk for recurrent iTTP, preeclampsia, and other maternal and fetal complications in subsequent pregnancies. ADAMTS13 activity during clinical remission has emerged as an important targetable risk factor for iTTP relapse and other outcomes including stroke and all-cause mortality. This review summarizes current literature regarding the epidemiology and potential mechanisms for adverse long-term sequelae of iTTP, outlines current best practices in iTTP survivorship care, and highlights a research agenda to improve long-term iTTP outcomes.

Association of Incidentally Discovered Covert Cerebrovascular Disease Identified Using Natural Language Processing and Future Dementia

Background Covert cerebrovascular disease (CCD) has been shown to be associated with dementia in population-based studies with magnetic resonance imaging (MRI) screening, but dementia risk associated with incidentally discovered CCD is not known. Methods and Results Individuals aged ≥50 years enrolled in the Kaiser Permanente Southern California health system receiving head computed tomography (CT) or MRI for nonstroke indications from 2009 to 2019, without prior ischemic stroke/transient ischemic attack, dementia/Alzheimer disease, or visit reason/scan indication suggestive of cognitive decline or stroke were included. Natural language processing identified incidentally discovered covert brain infarction (id-CBI) and white matter disease (id-WMD) on the neuroimage report; white matter disease was characterized as mild, moderate, severe, or undetermined. We estimated risk of dementia associated with id-CBI and id-WMD. Among 241 050 qualified individuals, natural language processing identified 69 931 (29.0%) with id-WMD and 11 328 (4.7%) with id-CBI. Dementia incidence rates (per 1000 person-years) were 23.5 (95% CI, 22.9-24.0) for patients with id-WMD, 29.4 (95% CI, 27.9-31.0) with id-CBI, and 6.0 (95% CI, 5.8-6.2) without id-CCD. The association of id-WMD with future dementia was stronger in younger (aged <70 years) versus older (aged ≥70 years) patients and for CT- versus MRI-discovered lesions. For patients with versus without id-WMD on CT, the adjusted HR was 2.87 (95% CI, 2.58-3.19) for older and 1.87 (95% CI, 1.79-1.95) for younger patients. For patients with versus without id-WMD on MRI, the adjusted HR for dementia risk was 2.28 (95% CI, 1.99-2.62) for older and 1.48 (95% CI, 1.32-1.66) for younger patients. The adjusted HR for id-CBI was 2.02 (95% CI, 1.70-2.41) for older and 1.22 (95% CI, 1.15-1.30) for younger patients for either modality. Dementia risk was strongly correlated with id-WMD severity; adjusted HRs compared with patients who were negative for id-WMD by MRI ranged from 1.41 (95% CI, 1.25-1.60) for those with mild disease on MRI to 4.11 (95% CI, 3.58-4.72) for those with severe disease on CT. Conclusions Incidentally discovered CCD is common and associated with a high risk of dementia, representing an opportunity for prevention. The association is strengthened when discovered at younger age, by increasing id-WMD severity, and when id-WMD is detected by CT scan rather than MRI.

Cognition and brain health among older adults in Iceland: the AGES-Reykjavik study

The paper aimed to compare how factors previously identified as predictive factors for cognitive decline and dementia related to cognitive performance on the one hand and brain health on the other. To that aim, multiple linear regression was applied to the AGES-Reykjavik study epidemiological data. Additionally, a regression analysis was performed for change in cognition over 5 years, using the same exposure factors. The study ran from 2002 to 2011, and the sample analyzed included 1707 participants between the ages of 66 and 90. The data contains MR imaging, cognitive testing, background data, and physiological measurements. Overall, we conclude that risk factors linked to dementia relate differently to cognition and brain health. Mobility, physical strength, alcohol consumption, coronary artery disease, and hypertension were associated with cognition and brain volume. Smoking, depression, diabetes, and body fat percentage were only associated with brain volume, not cognitive performance. Modifiable factors previously linked to cognitive reserve, such as educational attainment, participation in leisure activities, multilingualism and good self-reported health, were associated with cognitive function but did not relate to brain volume. These findings show that, within the same participant pool, cognitive reserve proxy variables have a relationship with cognitive performance but have no association with relative brain volume measured simultaneously.

Analysis of shared underlying mechanism in neurodegenerative disease

In this review, the relationship between bioenergetics, mitochondrial dysfunction, and inflammation will be and how they contribute to neurodegeneration, specifically in Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS) will be reviewed. Long-term changes in mitochondrial function, autophagy dysfunction, and immune activation are commonalities shared across these age-related disorders. Genetic risk factors for these diseases support an autophagy-immune connection in the underlying pathophysiology. Critical areas of deeper evaluation in these bioenergetic processes may lead to potential therapeutics with efficacy across multiple neurodegenerative diseases.

Association of Atrial Fibrillation and Cardioembolic Stroke with Poststroke Delirium Susceptibility: A Systematic Review and Meta-Analysis of Observational Studies

BACKGROUND

Several studies have shown atrial fibrillation (AF) and cardioembolic stroke (CES) to be associated with the risk of poststroke delirium (PSD). However, other studies have reported inconsistent results. We performed a comprehensive meta-analysis to clarify the associations between AF and CES and PSD susceptibility.

METHODS

We searched relevant studies meeting inclusion criteria in PubMed, Google Scholar, and Web of Science. Useful data were pooled, and odds ratios and 95% confidence intervals were calculated. We also assessed heterogeneity among studies, performed sensitivity analyses, and estimated publication bias.

RESULTS

This meta-analysis containing 18 observational studies proved that AF (odds ratio =2.30, 95% confidence interval = 2.00-2.65, P < 0.0001) was associated with an increased risk of PSD. CES was also found to have a higher risk of delirium compared with other types of stroke based on the Trial of Org 10172 in Acute Stroke Treatment classification (odds ratio = 2.02, 95% confidence interval = 1.47-2.79, P < 0.0001).

CONCLUSIONS

Our meta-analysis suggested that AF and CES contribute to increased risk of PSD.

Impact of catheter ablation versus medical therapy on cognitive function in atrial fibrillation: a systematic review

PURPOSE

Atrial fibrillation is associated with an increased risk of cognitive impairment. It is unclear whether the restoration of sinus rhythm with catheter ablation may modify this risk. We conducted a systematic review of studies comparing cognitive outcomes following catheter ablation with medical therapy (rate and/or rhythm control) in atrial fibrillation.

METHODS

Searches were performed on the following databases from their inception to 17 October 2021: PubMed, OVID Medline, Embase and Cochrane Library. The inclusion criteria comprised studies comparing catheter ablation against medical therapy (rate and/or rhythm control in conjunction with anticoagulation where appropriate) which included cognitive assessment and/or a diagnosis of dementia as an outcome.

RESULTS

A total of 599 records were screened. Ten studies including 15,886 patients treated with catheter ablation and 42,684 patients treated with medical therapy were included. Studies which compared the impact of catheter ablation versus medical therapy on quantitative assessments of cognitive function yielded conflicting results. In studies, examining new onset dementia during follow-up, catheter ablation was associated with a lower risk of subsequent dementia diagnosis compared to medical therapy (hazard ratio: 0.60 (95% confidence interval 0.42-0.88, p < 0.05)).

CONCLUSION

The accumulating evidence linking atrial fibrillation with cognitive impairment warrants the design of atrial fibrillation treatment strategies aimed at minimising cognitive decline. However, the impact of catheter ablation and atrial fibrillation medical therapy on cognitive decline is currently uncertain. Future studies investigating atrial fibrillation treatment strategies should include cognitive outcomes as important clinical endpoints.

Mediating roles of leukoaraiosis and infarcts in the effects of unilateral carotid artery stenosis on cognition

Background and objectives

Leukoaraiosis and infarcts are common in patients with carotid artery stenosis (CAS), and CAS severity, leukoaraiosis and infarcts all have been implicated in cognitive impairments. CAS severity was not only hypothesized to directly impede specific cognitive domains, but also transmit its effects indirectly to cognitive function through ipsilateral infarcts as well as periventricular leukoaraiosis (PVL) and deep white matter leukoaraiosis (DWML). We aimed to delineate the contributions of leukoaraiosis, infarcts and CAS to different specific cognitive domains.

Materials and methods

One hundred and sixty one participants with unilateral CAS (&gt;50%) on the left (n = 85) or right (n = 76) side and 65 volunteers without significant CAS (&lt;50%) were recruited. The PVL, DWML, and infarct severity were visually rated on MRI. A comprehensive cognitive battery was administered and standardized based on age norms. Correlation and mediation analyses were adopted to examine the direct and indirect influence of CAS, leukoaraiosis, and infarct on specific cognitive domains with adjustment for education, hypertension, diabetes mellitus, and hyperlipidemia.

Results

Carotid artery stenosis severity was associated with ipsilateral leukoaraiosis and infarct. Left CAS had direct effects on most cognitive domains, except for visual memory and constructional ability, and transmitted its indirect effects on all cognitive domains through ipsilateral PVL, and on constructional ability and psychomotor through infarcts. Right CAS only had negative direct effects on visual memory, psychomotor, design fluency and color processing speed, and transmitted its indirect effects on visual memory, word and color processing speed through ipsilateral infarcts. The trends of direct and indirect cognitive effects remained similar after covariate adjustment.

Conclusion

Left and right CAS would predominantly lead to verbal and non-verbal cognitive impairment respectively, and such effects could be mediated through CAS-related leukoaraiosis and infarct. Given that cognition is subject to heterogeneous pathologies, the exact relationships between markers of large and small vessel diseases and their composite prognostic effects on cognition requires further investigation.

Microstructural alterations measured by diffusion tensor imaging following transcatheter aortic valve replacement and their association with cerebral ischemic injury and cognitive function - a prospective study

PURPOSE

We assessed diffusion tensor imaging (DTI) metric changes of the corpus callosum and cingulum correlated to postprocedural ischemic lesion load (ILL) and cognitive performance in transcatheter aortic valve replacement (TAVR).

METHODS

TAVR subjects had DTI post-TAVR (≤ 8 days) and at 6 months (78 participants, males 56%, age 78.8 years ± 6.3) and four neurocognitive tests (pre-TAVR, post-TAVR, 6 months, 1 year). DTI metrics (fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD)) were calculated for 7 regions: corpus callosum (genu, body, splenium) and cingulum (cingulate gyrus, parahippocampal cingulum bilaterally). DTI metrics post-TAVR and at 6 months were compared with Student's t-test (p < 0.0071) and ANOVA covarying for sex, ILL (p < 0.05) with post hoc analysis of ILL groups (p < 0.0167). Repeated-measures linear mixed-effect model (p < 0.05) was performed to investigate the effect of time and ILL on cognition.

RESULTS

At 6 months, significant decrease of the following DTI metrics was detected: AD (genu, body, splenium, right parahippocampal cingulum: p ≤ 0.0046); MD (body, both cingulate gyri: p ≤ 0.0050); RD (left cingulate gyrus: p = 0.0021); FA (splenium: p < 0.0001). ANOVA confirmed significant effect of female sex on AD + MD reduction (body, right cingulate gyrus) and AD reduction (left cingulate gyrus) (p ≤ 0.0254). Significant negative effect of ILL on some DTI metric changes was found (AD + MD-body: p ≤ 0.0050; MD-left cingulate gyrus: p = 0.0087). Cognitive performance remained stable with significant negative correlation of ILL and retrograde memory and visual scores (p ≤ 0.0483).

CONCLUSION

Significant effect of TAVR on cerebral microstructural integrity was found with reduced diffusivities opposite to the trends reported in various neurodegenerative conditions/ageing, notably in women and lower ILL, and with preserved/improved cognition.

TRIAL REGISTRATION NUMBER

NCT02826200 at ClinicalTrials.gov; date of registration: 07. July 2016.

Migraine, Cognitive Decline, and Dementia in Older Adults: A Population-Based Study

Background: The potential impact of migraine on cognitive aging among older adults remains controversial. Objective: To examine the relationship of migraine and subtypes with cognitive decline and dementia in an older Swedish population. Methods: This population-based study included 3069 participants (age≥60) from the Swedish National study on Aging and Care in Kungsholmen, Stockholm. Baseline examination was conducted in 2001–2004, and participants were followed every 3 or 6 years until 2013–2016. Data were collected through face-to-face interviews, clinical examinations, laboratory tests, and linkage with registers. Global cognitive function was measured with the Mini-Mental State Examination (MMSE). Dementia was diagnosed according to the DSM-IV criteria. Migraine and subtypes were defined following the international classification system. Data were analyzed using logistic regression, Cox regression, and linear mixed-effects models. Results: At baseline, 305 participants were defined with non-migraine headache and 352 with migraine. The cross-sectional analysis showed that the multivariable-adjusted odds ratio (95% confidence interval) of prevalent dementia was 0.49 (0.20–1.21) for migraine and 0.66 (0.26–1.66) for migraine without aura. The longitudinal analysis showed that the multivariable-adjusted hazard ratios of incident dementia associated with migraine and subtypes ranged 0.68–0.89 (p > 0.05). Furthermore, migraine and subtypes were not significantly associated with either baseline MMSE score or MMSE changes during follow-ups (p > 0.05). The nonsignificant associations did not vary substantially by age, APOE ɛ4 allele, cerebrovascular disease, and antimigraine treatment (p for interactions > 0.05). Conclusion: This study shows no evidence supporting the associations of migraine and its subtypes with cognitive decline and dementia among older adults.

Artificial Intelligence-Enabled Electrocardiogram for Atrial Fibrillation Identifies Cognitive Decline Risk and Cerebral Infarcts

OBJECTIVE

To investigate whether artificial intelligence-enabled electrocardiogram (AI-ECG) assessment of atrial fibrillation (AF) risk predicts cognitive decline and cerebral infarcts.

PATIENTS AND METHODS

This population-based study included sinus-rhythm ECG participants seen from November 29, 2004 through July 13, 2020, and a subset with brain magnetic resonance imaging (MRI) (October 10, 2011, through November 2, 2017). The AI-ECG score of AF risk calculated for participants was 0-1. To determine the AI-ECG-AF relationship with baseline cognitive dysfunction, we compared linear mixed-effects models with global and domain-specific cognitive z-scores from longitudinal neuropsychological assessments. The AI-ECG-AF score was logit transformed and modeled with cubic splines. For the brain-MRI subset, logistic regression evaluated correlation of the AI-ECG-AF score and the high-threshold, dichotomized AI-ECG-AF score with infarcts.

RESULTS

Participants (N=3729; median age, 74.1 years) underwent cognitive analysis. Adjusting for age, sex, education, and APOE ɛ4-carrier status, the AI-ECG-AF score correlated with lower baseline and faster decline in global-cognitive z-scores (P=.009 and P=.01, respectively, non-linear-based spline-models tests) and attention z-scores (P<.001 and P=.01, respectively). Sinus-rhythm-ECG participants (n=1373) underwent MRI. As a continuous measure, the AI-ECG-AF score correlated with infarcts but not after age and sex adjustment (P=.52). For dichotomized analysis, an AI-ECG-AF score greater than 0.5 correlated with infarcts (OR, 4.61; 95% CI, 2.45-8.55; P<.001); even after age and sex adjustment (OR, 2.09; 95% CI, 1.06-4.07; P=.03).

CONCLUSION

The AI-ECG-AF score correlated with worse baseline cognition and gradual global cognition and attention decline. High AF probability by AI-ECG-AF score correlated with MRI cerebral infarcts. However, most infarcts observed in our cohort were subcortical, suggesting that AI-ECG not only predicts AF but also detects other non-AF cardiac disease markers and correlates with small vessel cerebrovascular disease and cognitive decline.

Association of Iatrogenic Infarcts With Clinical and Cognitive Outcomes in the Evaluating Neuroprotection in Aneurysm Coiling Therapy Trial

BACKGROUND AND OBJECTIVES

Small iatrogenic brain infarcts are often seen on diffusion-weighted MRI (DWI) following surgical or endovascular procedures, but there are few data on their clinical effects. We examined the association of iatrogenic infarcts with outcomes in the ENACT (Evaluating Neuroprotection in Aneurysm Coiling Therapy) randomized controlled trial of nerinetide in patients undergoing endovascular repair of intracranial aneurysms.

METHODS

In this post hoc analysis, we used multivariable models to evaluate the association of the presence and number of iatrogenic infarcts on DWI with neurologic impairment (NIH Stroke Scale [NIHSS]), functional status (modified Rankin Scale [mRS]), and cognitive and neuropsychiatric outcomes (30-minute test battery) at 1-4 days and 30 days postprocedure. We also related infarct number to a z score-derived composite outcome score using quantile regression.

RESULTS

Among 184 patients (median age 56 years [interquartile range (IQR) 50-64]), 124 (67.4%) had postprocedural DWI lesions (median 4, IQR 2-10.5). Nerinetide treatment was associated with fewer iatrogenic infarcts but no overall significant clinical treatment effects. Patients with infarcts had lower Mini-Mental State Examination (MMSE) scores at 2-4 days (median 28 vs 29, adjusted coefficient [acoef] -1.11, 95% CI -1.88 to -0.34, p = 0.005). Higher lesion counts were associated with worse day 1 NIHSS (adjusted odds ratio for NIHSS ≥1: 1.07, 1.02-1.12, p = 0.009), day 2-4 mRS (adjusted common odds ratio [acOR] 1.05, 1.01-1.09, p = 0.005), and day 2-4 MMSE (acoef -0.07, -0.13 to -0.003, p = 0.040) scores. At 30 days, infarct number remained associated with worse mRS (acOR 1.04, 1.01-1.07, p = 0.016) and Hopkins Verbal Learning Test (HVLT) delayed recall scores (acoef -0.21, -0.39 to -0.03, p = 0.020). Patients with infarcts trended towards lower 30-day Digit Symbol Substitution Test (DSST) scores (acoef -3.73, -7.36 to -0.10, p = 0.044). Higher lesion count was associated with worse composite outcome scores at both 1-4 days and 30 days (30-day acoef -0.12, 95% CI -0.21 to -0.03, p = 0.008). Among those with infarcts, day 1 NIHSS and day 2-4 mRS correlated with 30-day NIHSS, DSST, HVLT, and mRS scores, whereas day 2-4 MMSE correlated with 30-day NIHSS and DSST scores (Spearman ρ 0.47, p = 0.001).

DISCUSSION

Iatrogenic brain infarcts were associated with subtle differences in postprocedural (1-4 days) and 30-day outcomes on different measures in this middle-aged cohort, with earlier dysfunction correlating with later differences.

TRIAL REGISTRATION INFORMATION

Clinical trials registration NCT00728182.

The vascular risk factors and vascular neuropathology in subjects with autopsy-confirmed dementia with Lewy bodies

BACKGROUND

The frequency of vascular risk factors (VRFs) and the relationship between vascular pathology and cognitive function in neurodegenerative disease remains incompletely understood.

OBJECTIVE

The purpose of this study was to describe the frequency of VRFs and vascular pathology and explore the relationship between vascular pathology and cognitive function in dementia with Lewy bodies (DLB).

METHODS

This study included 363 autopsy-confirmed DLB and 753 Alzheimer's disease (AD) patients from the National Alzheimer's Coordinating Center (NACC) database. We used chi-squared test and analysis of variance to compare the VRFs and related factors in DLB and AD. Multinomial logistic regression and Spearman's correlation test were used to examine the relationship between vascular pathology and cognitive function.

RESULTS

No significant differences of VRFs were identified between DLB and AD. Alzheimer's disease patients had higher rates of microinfarcts (23.5% vs. 16.3%, p = 0.005) and moderate to severe amyloid angiopathy (45.9% vs. 36.1%, p = 0.002). In DLB patients, only cerebral amyloid angiopathy (CAA) pathology was negatively correlated with memory domain (r = -0.263, p < 0.001) and language (r = -0.112,p = 0.034). The rates of APOE ε4 allele carriers (60.0% vs. 44.9%, p = 0.004) and CAA pathology (45.9% vs.23.4%, p < 0.001) were much higher in the group with an intermediate likelihood of DLB than in the group with a high likelihood. There was a negative correlation between CAA pathology and memory (logical memory) in the group with an intermediate likelihood of DLB.

CONCLUSION

No difference of VRFs was identified between autopsy-confirmed DLB and AD. Cerebral amyloid angiopathy was shown to be an important pathology in DLB, which specifically correlated with memory and language. The groups with high and intermediate likelihood of DLB differed in terms of CAA pathology, and CAA pathology may play an important role in the development of DLB.

Post-Stroke Cognitive Impairment: Epidemiology, Risk Factors, and Management

Stroke, characterized as a neurological deficit of cerebrovascular cause, is very common in older adults. Increasing evidence suggests stroke contributes to the risk and severity of cognitive impairment. People with cognitive impairment following stroke often face with quality-of-life issues and require ongoing support, which have a profound effect on caregivers and society. The high morbidity of post-stroke cognitive impairment (PSCI) demands effective management strategies, in which preventive strategies are more appealing, especially those targeting towards modifiable risk factors. In this review article, we attempt to summarize existing evidence and knowledge gaps on PSCI: elaborating on the heterogeneity in current definitions, reporting the inconsistent findings in PSCI prevalence in the literature, exploring established or less established predictors, outlining prevention and treatment strategies potentially effective or currently being tested, and proposing promising directions for future research.

Functional Abilities of an International Post-Stroke Population: Standard Assessment of Global Everyday Activities (SAGEA) Scale

BACKGROUND AND OBJECTIVES

Function is an important outcome after stroke; traditional assessments may not capture functional deficits important to patients. We examined the validity of the Standard Assessment of Global Everyday Activities (SAGEA), a patient-reported outcome that assesses activities important to patients and for use in international clinical trials.

METHODS

The NAVIGATE-ESUS trial evaluated rivaroxaban compared to aspirin in preventing recurrent stroke in 7213 participants. The Modified Rankin Scale (mRS), the National Institutes of Health Stroke Scale (NIHSS), and the SAGEA were collected at entry. Chi square tests were used to compare proportions and Spearman rank correlations were used to compare between measures. SAGEA was compared to the Modified Frailty Index (MFI) and the occurrence of infarct to examine criterion validity RESULTS: Participants were 67 years, 2/3 were male, and at baseline 30% had no disability and 58% had slight disability according to mRS scores. SAGEA was weakly correlated with the mRS (r=0.37), the NIHSS (r=0.29) and the MFI (r=0.30). Of the 2154 with an mRS score of 0, 61% reported difficulty on the SAGEA. The largest discrepancies between SAGEA and other measures were because of cognitive functional deficits detected by the SAGEA that were not identified on other assessments. A larger number of MRI identified infarcts (acute and covert) were associated with a higher SAGEA score (p=0.007).

CONCLUSIONS

The SAGEA is a simple, globally applicable measure of cognitive and functional abilities that identifies issues that other commonly used assessments of disability and function do not capture.

Atrial Fibrillation and Dementia: A Report From the AF-SCREEN International Collaboration

Growing evidence suggests a consistent association between atrial fibrillation (AF) and cognitive impairment and dementia that is independent of clinical stroke. This report from the AF-SCREEN International Collaboration summarizes the evidence linking AF to cognitive impairment and dementia. It provides guidance on the investigation and management of dementia in patients with AF on the basis of best available evidence. The document also addresses suspected pathophysiologic mechanisms and identifies knowledge gaps for future research. Whereas AF and dementia share numerous risk factors, the association appears to be independent of these variables. Nevertheless, the evidence remains inconclusive regarding a direct causal effect. Several pathophysiologic mechanisms have been proposed, some of which are potentially amenable to early intervention, including cerebral microinfarction, AF-related cerebral hypoperfusion, inflammation, microhemorrhage, brain atrophy, and systemic atherosclerotic vascular disease. The mitigating role of oral anticoagulation in specific subgroups (eg, low stroke risk, short duration or silent AF, after successful AF ablation, or atrial cardiopathy) and the effect of rhythm versus rate control strategies remain unknown. Likewise, screening for AF (in cognitively normal or cognitively impaired patients) and screening for cognitive impairment in patients with AF are debated. The pathophysiology of dementia and therapeutic strategies to reduce cognitive impairment warrant further investigation in individuals with AF. Cognition should be evaluated in future AF studies and integrated with patient-specific outcome priorities and patient preferences. Further large-scale prospective studies and randomized trials are needed to establish whether AF is a risk factor for cognitive impairment, to investigate strategies to prevent dementia, and to determine whether screening for unknown AF followed by targeted therapy might prevent or reduce cognitive impairment and dementia.

Risk Factors, Lifestyle Behaviors, and Vascular Brain Health

Although a relationship between traditional cardiovascular risk factors and stroke has long been recognized, these risk factors likely play a role in other aspects of brain health. Clinical stroke is only the tip of the iceberg of vascular brain injury that includes covert infarcts, white matter hyperintensities, and microbleeds. Furthermore, an individual's risk for not only stroke but poor brain health includes not only these traditional vascular risk factors but also lifestyle and genetic factors. The purpose of this narrative review is to summarize the state of the evidence on traditional and nontraditional vascular risk factors and their contributions to brain health. Additionally, we will review important modifiers that interact with these risk factors to increase, or, in some cases, reduce risk of adverse brain health outcomes, with an emphasis on genes and biomarkers associated with Alzheimer disease. Finally, we will consider the importance of social determinants of health in brain health outcomes.

Depression and Dementia: The Role of Cortisol and Vascular Brain Lesions. AGES-Reykjavik Study

BACKGROUND

Late-life depression (LLD) is related to an increased risk of developing dementia; however, the biological mechanisms explaining this relationship remain unclear.

OBJECTIVE

To determine whether the relationship between LLD and dementia can be best explained by the glucocorticoid cascade or vascular hypothesis.

METHODS

Data are from 4,354 persons (mean age 76±5 years) without dementia at baseline from the AGES-Reykjavik Study. LLD was assessed with the MINI diagnostic interview (current and remitted major depressive disorder [MDD]) and the Geriatric Depression Scale-15. Morning and evening salivary cortisol were collected (glucocorticoid cascade hypothesis). White matter hyperintensities (WMH; vascular hypothesis) volume was assessed using 1.5T brain MRI. Using Cox proportional hazard models, we estimated the associations of LLD, cortisol levels, and WMH volume with incident all-cause dementia, AD, and non-AD dementia.

RESULTS

During 8.8±3.2 years of follow-up, 843 persons developed dementia, including 397 with AD. Current MDD was associated with an increased risk of developing all-cause dementia (HR = 2.17; 95% CI 1.66-2.67), with risks similar for AD and non-AD, while remitted MDD was not (HR = 1.02; 95% CI 0.55-1.49). Depressive symptoms were also associated with increased risk of dementia, in particular non-AD dementias. Higher levels of evening cortisol increased risk of dementia, but this was independent of MDD. WMH partially explained the relation between current MDD and dementia risk but remained increased (HR = 1.71; 95% CI 1.34-2.08).

CONCLUSION

The current study highlights the importance of LLD in developing dementia. However, neither the glucocorticoid cascade nor the vascular hypotheses fully explained the relation between depression and dementia.

Cerebrovascular Risk-Factors of Prevalent and Incident Brain Infarcts in the General Population: The AGES-Reykjavik Study

BACKGROUND AND PURPOSE

Studies on the association of cerebrovascular risk factors to magnetic resonance imaging detected brain infarcts have been inconsistent, partly reflecting limits of assessment to infarcts anywhere in the brain, as opposed to specific brain regions. We hypothesized that risk-factors may differ depending on where the infarct is located in subcortical-, cortical-, and cerebellar regions.

METHODS

Participants (n=2662, mean age 74.6±4.8) from the longitudinal population-based AGES (Age, Gene/Environment Susceptibility)-Reykjavik Study underwent brain magnetic resonance imaging at baseline and on average 5.2 years later. We assessed the number and location of brain infarcts (prevalent versus incident). We estimated the risk-ratios of prevalent (PRR) and incident (IRR) infarcts by baseline cerebrovascular risk-factors using Poisson regression.

RESULTS

Thirty-one percent of the study participants had prevalent brain infarcts and 21% developed new infarcts over 5 years. Prevalent subcortical infarcts were associated with hypertension (PRR, 2.7 [95% CI, 1.1-6.8]), systolic blood pressure (PRR, 1.2 [95% CI, 1.1-1.4]), and diabetes (PRR, 2.8 [95% CI, 1.9-4.1]); incident subcortical infarcts were associated with systolic (IRR, 1.2 [95% CI, 1.0-1.4]) and diastolic (IRR, 1.3 [95% CI, 1.0-1.6]) blood pressure. Prevalent and incident cortical infarcts were associated with carotid plaques (PRR, 1.8 [95% CI, 1.3-2.5] and IRR, 1.9 [95% CI, 1.3-2.9], respectively), and atrial fibrillation was significantly associated with prevalent cortical infarcts (PRR, 1.8 [95% CI, 1.2-2.7]). Risk-factors for prevalent cerebellar infarcts included hypertension (PRR, 2.45 [95% CI, 1.5-4.0]), carotid plaques (PRR, 1.45 [95% CI, 1.2-1.8]), and migraine with aura (PRR, 1.6 [95% CI, 1.1-2.2]). Incident cerebellar infarcts were only associated with any migraine (IRR, 1.4 [95% CI, 1.0-2.0]).

CONCLUSIONS

The risk for subcortical infarcts tends to increase with small vessel disease risk-factors such as hypertension and diabetes. Risk for cortical infarcts tends to increase with atherosclerotic/coronary processes and risk for cerebellar infarcts with a more mixed profile of factors. Assessment of risk-factors by location of asymptomatic infarcts found on magnetic resonance imaging may improve the ability to target and optimize preventive therapeutic approaches to prevent stroke.

Neurologic Dysfunction and Neuroprotection in Transcatheter Aortic Valve Implantation

Transcatheter aortic valve implantation (TAVI) is a fast-growing procedure. Expanding to low-risk patients, it has surpassed surgical aortic valve implantation in frequency and has been associated with excellent outcomes. Stroke is a devastating complication after transcatheter aortic valve implantation. Silent brain infarcts identified by diffusion-weighted magnetic resonance imaging are present in most patients following TAVI. Postoperative delirium and cognitive dysfunction are common neurologic complications. The stroke and silent brain infarcts are likely caused by particulate emboli released during the procedure. Intravascularly positioned cerebral embolic protection devices are designed to prevent debris from entering the aortic arch vessels to avoid stroke. Despite promising design, randomized clinical trials have not demonstrated a reduction in stroke in patients receiving cerebral embolic protection devices. Similarly, the association of cerebral embolic protection devices with silent brain infarcts, postoperative delirium, and cognitive dysfunction is uncertain. Monitored anesthesia care or conscious sedation is as safe as general anesthesia and is associated with lower cost, but different anesthetic techniques have not been shown to decrease stroke risk, postoperative delirium, or cognitive dysfunction. Anesthesiologists play important roles in providing perioperative care including management of neurologic events in patients undergoing TAVI. Large randomized clinical trials are needed that focus on the correlation between perioperative interventions and neurologic outcomes.

Atrial Fibrillation Is Associated with Cognitive Impairment, All-Cause Dementia, Vascular Dementia, and Alzheimer's Disease: a Systematic Review and Meta-Analysis

BACKGROUND

Atrial fibrillation (AF) is a risk factor for cognitive impairment and dementia in patients with stroke history. However, the association between AF and cognitive impairment in broader populations is less clear.

OBJECTIVE

To systematically review and quantitatively synthesize the existing evidence regarding the association of AF with cognitive impairment of any severity and etiology and dementia.

METHODS

Medline, Scopus, and Cochrane Central were searched in order to identify studies investigating the association between AF and cognitive impairment (or dementia) cross-sectionally and longitudinally. Studies encompassing and analyzing exclusively patients with stroke history were excluded. A random-effects model meta-analysis was conducted. Potential sources of between-study heterogeneity were investigated via subgroup and meta-regression analyses. Sensitivity analyses including only studies reporting data on stroke-free patients, vascular dementia, and Alzheimer's disease were performed.

RESULTS

In total, 43 studies were included. In the pooled analysis, AF was significantly associated with dementia (adjusted OR, 1.6; 95% CI, 1.3 to 2.1; I², 31%) and the combined endpoint of cognitive impairment or dementia (pooled adjusted OR, 1.5; 95% CI, 1.4 to 1.8; I², 34%). The results were significant, even when studies including only stroke-free patients were pooled together (unadjusted OR, 2.2; 95% CI, 1.4 to 3.5; I², 96%), but the heterogeneity rates were high. AF was significantly associated with increased risk of both vascular (adjusted OR, 1.7; 95% CI, 1.2 to 2.3; I², 43%) and Alzheimer's dementia (adjusted HR, 1.4; 95% CI, 1.2 to 1.6; I², 42%).

CONCLUSION

AF increases the risk of cognitive impairment, all-cause dementia, vascular dementia, and Alzheimer's disease. Future studies should employ interventions that may delay or even prevent cognitive decline in AF patients.

Association between Circulating Protein C Levels and Incident Dementia: The Atherosclerosis Risk in Communities Study

INTRODUCTION

Hemostasis depends on the delicate balance between coagulants and anticoagulants. Higher levels of circulating coagulants have been associated with higher risk of cerebral infarctions and dementia. In contrast, higher levels of circulating protein C, an endogenous anticoagulant, have been associated with lower risk of cerebral infarctions, and the association between protein C levels and the risk of dementia is unknown. The goal of this study was to evaluate the association of circulating protein C levels in midlife and late life with incident dementia.

METHODS

Circulating protein C levels were measured using blood samples collected at the midlife baseline (1987-1989) and the late-life baseline (2011-2013) among 14,462 and 3,614 participants, respectively, in the Atherosclerosis Risk in Communities study. Protein C levels were measured using enzyme-linked immunosorbent assay at midlife and a modified aptamer-based assay at late life. Participants were followed up to 2013 from midlife and up to 2017 from late life. Incident dementia was ascertained during the follow-up periods using in-person cognitive and functional assessment, informant interviews, and International Classification of Diseases codes at hospitalization discharge and on death certificates. Cause-specific Cox regression models were used to evaluate the association between quintiles of circulating protein C and incident dementia.

RESULTS

From midlife (mean age of 54), 1,389 incident dementia events were observed over a median follow-up of 23 years. From late life (mean age of 75), 353 incident dementia events were observed over a median follow-up of 4.9 years. At both midlife and late life, circulating protein C had an inverse association with incident dementia after adjusting for demographic, vascular, and hemostatic risk factors, incident stroke as time-dependent covariate, and incorporating stabilized weights based on propensity scores (quintile 5 vs. quintile 1 as the reference, midlife hazard ratio 0.80, 95% confidence interval 0.66-0.96, p value for trend 0.04; late-life hazard ratio 0.84, 95% confidence interval: 0.55-1.28, p value for trend 0.04).

DISCUSSION/CONCLUSION

Circulating protein C has an inverse association with incident dementia independent of established risk factors, including stroke. Our results suggest studying anticoagulants in addition to coagulants can increase our understanding on the relationship between hemostasis and dementia.

Silent brain infarcts and early cognitive outcomes after transcatheter aortic valve implantation: a systematic review and meta-analysis

BACKGROUND

Silent brain infarcts (SBIs) are frequently identified after transcatheter aortic valve implantation (TAVI), when patients are screened with diffusion-weighted magnetic resonance imaging (DW-MRI). Outside the cardiac literature, SBIs have been correlated with progressive cognitive dysfunction; however, their prognostic utility after TAVI remains uncertain. This study's main goals were to explore (i) the incidence of and potential risk factors for SBI after TAVI; and (ii) the effect of SBI on early post-procedural cognitive dysfunction (PCD).

METHODS AND RESULTS

A systematic literature review was performed to identify all publications reporting SBI incidence, as detected by DW-MRI after TAVI. Silent brain infarct incidence, baseline characteristics, and the incidence of early PCD were evaluated via meta-analysis and meta-regression models. We identified 39 relevant studies encapsulating 2408 patients. Out of 2171 patients who underwent post-procedural DW-MRI, 1601 were found to have at least one new SBI (pooled effect size 0.76, 95% CI: 0.72-0.81). The incidence of reported stroke with focal neurological deficits was 3%. Meta-regression noted that diabetes, chronic renal disease, 3-Tesla MRI, and pre-dilation were associated with increased SBI risk. The prevalence of early PCD increased during follow-up, from 16% at 10.0 ± 6.3 days to 26% at 6.1 ± 1.7 months and meta-regression suggested an association between the mean number of new SBI and incidence of PCD. The use of cerebral embolic protection devices (CEPDs) appeared to decrease the volume of SBI, but not their overall incidence.

CONCLUSIONS

Silent brain infarcts are common after TAVI; and diabetes, kidney disease, and pre-dilation increase overall SBI risk. While higher numbers of new SBIs appear to adversely affect early neurocognitive outcomes, long-term follow-up studies remain necessary as TAVI expands to low-risk patient populations. The use of CEPD did not result in a significant decrease in the occurrence of SBI.

Iatrogenic Diffusion-Weighted Imaging Lesions: What Is Their Impact and How Can It Be Measured?

Infarct volume in acute ischemic stroke is closely linked with clinical outcome, with larger infarct volumes being associated with a worse prognosis. Small iatrogenic infarcts, which can occur as a result of surgical or endovascular procedures, are often only seen on diffusion-weighted MR imaging. They often do not lead to any overtly appreciable clinical deficits, hence the term covert or silent infarcts. There is relative paucity of data on the clinical impact of periprocedural hyperintense diffusion-weighted MR imaging lesions, partly because they commonly remain undiagnosed. Clearly, a better understanding of iatrogenic periprocedural diffusion-weighted MR imaging lesions and their clinical significance is needed. In this article, we describe the current limitations of our understanding of the significance of iatrogenic diffusion-weighted MR imaging lesions using exemplary data from the ENACT trial (Safety and Efficacy of NA-1 in Patients With Iatrogenic Stroke After Endovascular Aneurysm Repair) and outline a framework for how to investigate their clinical impact.

Post-stroke Cognition at 1 and 3 Years Is Influenced by the Location of White Matter Hyperintensities in Patients With Lacunar Stroke

Lacunar strokes are a common type of ischemic stroke. They are known to have long-term cognitive deficits, but the influencing factors are still largely unknown. We investigated if the location of the index lacunar stroke or regional WMH and their change at 1 year could predict the cognitive performance at 1 and 3 years post-stroke in lacunar stroke patients. We used lacunar lesion location and WMH-segmented data from 118 patients, mean age 64.9 who had a brain MRI scan soon after presenting with symptoms, of which 88 had a repeated scan 12 months later. Premorbid intelligence (National Adult Reading Test) and current intelligence [Addenbrooke's Cognitive Exam-Revised (ACE-R)] were measured at 1, 12, and 36 months after the stroke. ANCOVA analyses adjusting for baseline cognition/premorbid intelligence, vascular risk factors, age, sex and total baseline WMH volume found that the recent small subcortical infarcts (RSSI) in the internal/external capsule/lentiform nucleus and centrum semiovale did not predict cognitive scores at 12 and 36 months. However, RSSI location moderated voxel-based associations of WMH change from baseline to 1 year with cognitive scores at 1 and 3 years. WMH increase in the external capsule, intersection between the anterior limb of the internal and external capsules, and optical radiation, was associated with worsening of ACE-R scores 1 and 3 years post-stroke after accounting for the location of the index infarct, age and baseline cognition.

Case Report of a pathologically confirmed vascular parkinsonism with early cognitive impairment and Behavioral disturbance

Background

Vascular Parkinsonism(VaP) is defined as parkinsonism resulting from cerebral vascular disease(CVD), with presence of variable motor and non-motor signs that are corroborated by clinical, anatomic or imaging findings of cerebrovascular disease. Overlapping syndromes with mixed pathologies make VaP difficult to distinguish from primary neurodegenerative parkinsonism.To understand the clinical and pathological features of VaP,we report a case of autopsy confirmed vascular Parkinsonism that was clinical misdiagnosed as idiopathic Parkinson’s disease.Clinical features include early mixed symptoms of dementia,behavioral disturbance and parkinsonism that were similar to Dementia with lewy Body(DLB) and Parkinson disease Dementia(PDD).

Case presentation

A 84-year-old man presented progressive parkinsonism with prominent postural instability, gait impairment, pseudobulbar, early cognitive impairment, irritability, hallucination, urinary symptoms and poor responsiveness to dopaminergic drugs. He was clinically diagnosed as Parkinson disease(PD). In the post-mortem study, we examined Aβ and phospho-tau as pathological biomarker for Alzheimer’s disease(AD), α-synucleing in medulla, pons and midbrain for PD and DLB. Hematoxylin and eosin staining in cerebral cortex, cerebellum and brainstem examines vascular pathological changes and microvascular lesion.Neither Lewy bodies in the substantia nigra ,locus ceruleus and cerebrumnor accumulation of Aβ, neurofibrillary tangles were noted. Instead, there were many cerebral infarctions and widespread arteriosclerosis in the brain. The final brain autopsy supported a diagnosis of VaP not PD.

Conclusions

This case of pathologically confirmed VaP misdiagnosed as idiopathic PD suggested that we must be vigilant about the possibility of VaP for patients with parkinsonisms, cognitive impairments, early behavioral and psychological symptoms,imaging performances of cerebral small vessel disease and other vascular damages.

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.

Incident cerebral lacunes: A review

Lacunes on magnetic resonance imaging (MRI) are considered as a key hallmark for evaluating the progression and severity of cerebral small vessel diseases. We aimed to review the MRI diagnostic criteria, frequency, predictors and clinical impact of incident lacunes in the largest longitudinal studies. Analyses were restricted to cohort studies of more than 50 individuals that investigated incident lacunes over a duration of at least one year. We observed that: (1) MRI parameters and definition of lacunes are inconsistent across studies, (2) the frequency of incident lacunes is strongly related to the previous clinical and MRI status at individual level, (3) both age and hypertension diagnosed at onset predict incident lacunes but the exact impact of blood pressure level during follow-up remains undetermined, (4) the clinical correlates of these lesions on cognition are repeatedly observed but the exact consequences on motor or gait performances are not always evaluated. Homogenization of imaging techniques, the use of strict diagnostic criteria and a broader clinical assessment considering motor and gait performances should be recommended in future longitudinal studies of incident lacunes including clinical trials testing preventative treatments in cerebral small vessel diseases.

Association Between Atrial Fibrillation and Cognitive Impairment in Individuals With Prior Stroke: A Meta-Analysis and Meta-Regression Analysis

Background and Purpose- Atrial fibrillation (AF) is the most common chronic arrhythmia. Dementia and cognitive impairment (CI) are major burdens to public health. The prevalence of all 3 entities is projected to increase due to population aging. Previous reports have linked AF with a higher risk of CI and dementia in patients without prior stroke. Stroke is known to increase the risk for dementia and CI. It is unclear if AF in patients with history of stroke can further increase the risk for dementia or CI. Our purpose was to evaluate the impact of AF on risk for dementia or CI among patients with history of stroke. Methods- Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines were followed. Pubmed, Scopus, and Cochrane central were searched. The outcomes of interest were dementia, CI, and the composite end point of dementia or CI. A random-effect model meta-analysis was performed. Meta-regression analysis was also performed. Publication bias was assessed with the Egger test and with funnel plots. Results- Fourteen studies and 14 360 patients (1363 with AF) were included in the meta-analysis. In the meta-analysis of adjusted odds ratio, AF was associated with increased risk of CI (odds ratio, 1.60 [95% CI, 1.20-2.14]), dementia (odds ratio, 3.11 [95% CI, 2.05-4.73]), and the composite end point of CI or dementia (odds ratio, 2.26 [95% CI, 1.61-3.19]). The heterogeneity for the composite end point of dementia or CI was moderate (adjusted analysis). The heterogeneity for the analysis of the end point of CI only was substantial in the unadjusted analysis and moderate in the adjusted analysis. The heterogeneity for the end point of dementia only was moderate in the unadjusted analysis and zero in the adjusted analysis. Conclusions- Our results indicate that an association between AF and CI or dementia is patients with prior strokes is possible given the persistent positive associations we noticed in the unadjusted and adjusted analyses. The heterogeneity levels limit the certainty of our findings.

Reduced Cognitive Assessment Scores Among Individuals With Magnetic Resonance Imaging–Detected Vascular Brain Injury

Background and Purpose—

Little is known about the association between covert vascular brain injury and cognitive impairment in middle-aged populations. We investigated if scores on a cognitive screen were lower in individuals with higher cardiovascular risk, and those with covert vascular brain injury.

Methods—

Seven thousand five hundred forty-seven adults, aged 35 to 69 years, free of cardiovascular disease underwent a cognitive assessment using the Digital Symbol Substitution test and Montreal Cognitive Assessment, and magnetic resonance imaging (MRI) to detect covert vascular brain injury (high white matter hyperintensities, lacunar, and nonlacunar brain infarctions). Cardiovascular risk factors were quantified using the INTERHEART (A Global Study of Risk Factors for Acute Myocardial Infarction) risk score. Multivariable mixed models tested for independent determinants of reduced cognitive scores. The population attributable risk of risk factors and MRI vascular brain injury on low cognitive scores was calculated.

Results—

The mean age of participants was 58 (SD, 9) years; 55% were women. Montreal Cognitive Assessment and Digital Symbol Substitution test scores decreased significantly with increasing age ( P <0.0001), INTERHEART risk score ( P <0.0001), and among individuals with high white matter hyperintensities, nonlacunar brain infarction, and individuals with 3+ silent brain infarctions. Adjusted for age, sex, education, ethnicity covariates, Digital Symbol Substitution test was significantly lowered by 1.0 (95% CI, −1.3 to −0.7) point per 5-point cardiovascular risk score increase, 1.9 (95% CI, −3.2 to −0.6) per high white matter hyperintensities, 3.5 (95% CI, −6.4 to −0.7) per nonlacunar stroke, and 6.8 (95% CI, −11.5 to −2.2) when 3+ silent brain infarctions were present. No postsecondary education accounted for 15% (95% CI, 12–17), moderate and high levels of cardiovascular risk factors accounted for 19% (95% CI, 8–30), and MRI vascular brain injury accounted for 10% (95% CI, −3 to 22) of low test scores.

Conclusions—

Among a middle-aged community-dwelling population, scores on a cognitive screen were lower in individuals with higher cardiovascular risk factors or MRI vascular brain injury. Much of the population attributable risk of low cognitive scores can be attributed to lower educational attainment, higher cardiovascular risk factors, and MRI vascular brain injury.