The Brief Memory and Executive Test (BMET) for detecting vascular cognitive impairment in small vessel disease: a validation study

Are we ready to cure post-stroke cognitive impairment? Many key prerequisites can be achieved quickly and easily

PURPOSE

Post-stroke (PS) cognitive impairment (CI) is frequent and its devastating functional and vital consequences are well known. Despite recent guidelines, they are still largely neglected. A large number of recent studies have re-examined the epidemiology, diagnosis, imaging determinants and management of PSCI. The aim of this update is to determine whether these new data answer the questions that are essential to reducing PSCI, the unmet needs, and steps still to be taken.

METHODS

Literature review of stroke unit-era studies examining key steps in the management of PSCI: epidemiology and risk factors, diagnosis (cognitive profile and assessments), imaging determinants (quantitative measures, voxelwise localization, the disconnectome and associated Alzheimer's disease [AD]) and treatment (secondary prevention, symptomatic drugs, rehabilitation and noninvasive brain stimulation) of PSCI.

FINDINGS

(1) the prevalence of PSCI of approximately 50% is probably underestimated; (2) the sensitivity of screening tests should be improved to detect mild PSCI; (3) comprehensive assessment is now well-defined and should include apathy; (4) easily available factors can identify patients at high risk of PSCI; (5) key imaging determinants are the location and volume of the lesion and the resulting disconnection, associated AD and brain atrophy; WMH, ePVS, microhemorrhages, hemosiderosis, and cortical microinfarcts may contribute to cognitive impairment but are more likely to be markers of brain vulnerability or associated AD that reduce PS recovery; (6) remote and online assessment is a promising approach for selected patients; (7) secondary stroke prevention has not been proven to prevent PSCI; (8) symptomatic drugs are ineffective in treating PSCI and apathy; (9) in addition to cognitive rehabilitation, the benefits of training platforms and computerized training are yet to be documented; (10) the results and the magnitude of improvement of noninvasive brain stimulation, while very promising, need to be substantiated by large, high-quality, sham-controlled RCTs.

DISCUSSION AND CONCLUSION

These major advances pave the way for the reduction of PSCI. They include (1) the development of more sensitive screening tests applicable to all patients and (2) online remote assessment; crossvalidation of (3) clinical and (4) imaging factors to (5) identify patients at risk, as well as (6) factors that prompt a search for associated AD; (7) the inclusion of cognitive outcome as a secondary endpoint in acute and secondary stroke prevention trials; and (8) the validation of the benefit of noninvasive brain stimulation through high-quality, randomized, sham-controlled trials. Many of these objectives can be rapidly and easily attained.

Pathophysiology, Assessment, and Management of Post-Stroke Cognitive Impairment, Depression, and Fatigue

Post-stroke cognitive impairment, depression, and fatigue are common, persistent, and disabling. This review summarizes current knowledge on the pathophysiology, assessment, and management of these debilitating neuropsychiatric sequelae of stroke. We briefly review evolving knowledge on the neural mechanisms and risk factors for each condition. We describe patient-reported outcome measures and clinician rating techniques that can be used to assist in screening and comprehensive assessment. We then discuss behavioral and pharmacologic management strategies. Heterogeneity of stroke remains a challenge in management and new research is still needed to optimize and personalize treatments for stroke survivors.

Screening for post-stroke neurocognitive disorders in diverse populations: A systematic review

Objective: Although neurocognitive disorders (NCD) are common post-stroke, many populations do not have adapted cognitive screens and cut-offs. We therefore reviewed the appropriateness of the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and Oxford Cognitive Screen (OCS) for diagnosing NCD in culturally diverse stroke populations. Method: Using an extensive search string, diagnostic accuracy studies for MMSE, MoCA and OCS in the stroke population were retrieved from four databases. We compared translations and adaptations, adjustments in scores and cut-offs, and their diagnostic accuracy. Results: The search resulted in 28 MMSE, 39 MoCA and 5 OCS-studies in 13 western, educated, industrialized, rich and democratic (WEIRD) and 4 other countries. There was a lack of studies on South-American, African, and non-Chinese-Asian populations. All three tests needed adaptation for less WEIRD populations and populations with languages with non-Latin features. Optimal MMSE and OCS subtest cut-offs were similar across WEIRD and less WEIRD populations, whereas optimal MoCA cut-offs appeared lower for less WEIRD populations. The use of adjusted scores resulted in different optimal cut-offs or similar cut-offs with better accuracy. Conclusions: MoCA, MMSE and OCS are promising tools for diagnosing post-stroke-NCD. For culturally diverse populations, translation, adaptation and adjusted scores or cut-offs are necessary for diagnostic accuracy. Available studies report scarcely about their sample's cultural background and there is a lack of diagnostic accuracy studies in less WEIRD or culturally diverse populations. Future studies should report more cultural characteristics of their sample to provide better insight into the tests' accuracy in culturally diverse populations.

Improvement of an External Predictive Model Based on New Information Using a Synthetic Data Approach: Application to CADASIL

Background and Objectives

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most frequent hereditary cerebral small vessel disease. It is caused by mutations of the NOTCH3 gene. The disease evolves progressively over decades leading to stroke, disability, cognitive decline, and functional dependency. The course and clinical severity of CADASIL seem heterogeneous. Predictive models are thus needed to improve prognostic evaluation and inform future clinical trials. A predictive model of the 3-year variation in the Mattis Dementia Rating Scale (MDRS), which reflects the global cognitive performance of patients with CADASIL, was previously proposed. This model made predictions based on demographic, clinical, and MRI data. We aimed to improve this existing predictive model by integrating a new potential factor, the location of the genetic mutation in the different epidermal growth factor (EGFr) domains of the NOTCH3 gene, dichotomized into EGFr domains 1 to 6 or 7 to 34.

Methods

We used a new synthetic data approach to improve the initial predictive model by incorporating additional genetic information. This method combined the predicted outcomes from the previous model and 5 "synthetic" data sets with the observed outcome in a new data set. We then applied a multiple imputation method for missing data on the mutation location.

Results

The new data set included 367 patients who were followed up for 30 to 42 months. In the multivariable model with synthetic data, patients with NOTCH3 mutations in EGFr domains 7 to 34 had an additional average decrease of -1.4 points (standard error 0.67, p = 0.035) in their MDRS score variation over 3 years compared with patients with mutations located in EGFr domains 1 to 6. Cross-validation results highlighted the improved predictive performance of the enhanced model. Moreover, the model estimation was found to be more robust than fitting a model without synthetic data.

Discussion

The use of synthetic data improved the predictive model of MDRS change over 3 years in CADASIL. The predictive performance and estimation robustness of the predictive model were enhanced using this approach, whether genetic information was used. A statistically significant association between the location of the mutation in the NOTCH3 gene and the 3-year MDRS score variation was detected.

New horizons in cognitive and functional impairment as a consequence of cerebral small vessel disease

Cerebral small vessel disease (cSVD) is a frequent finding in imaging of the brain in older adults, especially in the concomitance of cardiovascular disease risk factors. Despite the well-established link between cSVD and (vascular) cognitive impairment (VCI), it remains uncertain how and when these vascular alterations lead to cognitive decline. The extent of acknowledged markers of cSVD is at best modestly associated with the severity of clinical symptoms, but technological advances increasingly allow to identify and quantify the extent and perhaps also the functional impact of cSVD more accurately. This will facilitate a more accurate diagnosis of VCI, against the backdrop of concomitant other neurodegenerative pathology, and help to identify persons with the greatest risk of cognitive and functional deterioration. In this study, we discuss how better assessment of cSVD using refined neuropsychological and comprehensive geriatric assessment as well as modern image analysis techniques may improve diagnosis and possibly the prognosis of VCI. Finally, we discuss new avenues in the treatment of cSVD and outline how these contemporary insights into cSVD can contribute to optimise screening and treatment strategies in older adults with cognitive impairment and multimorbidity.

The nonverbal BriefScreen: A cognitive screening method for patients with limited language and motor abilities

Dementia and significant cognitive decline are frequent sequelae of stroke, but are difficult to evaluate when aphasia and/or motor impairment are present. The linguistic and motor requirements of commonly employed screening tests render them problematic for use post-stroke. The present study examines the validity of the Nonverbal BriefScreen, a brief screening method with limited verbal and motor requirements, in groups of patients with known cognitive impairment using the MMSE as a gold standard. Participants were 137 healthy middle aged and older community dwellers, 21 patients with MCI/early dementia and 35 patients with different types of dementia. The sensitivity and specificity of the Nonverbal BriefScreen were calculated for various cutoff scores, with the MMSE as comparison. The Nonverbal BriefScreen was effective in discriminating between healthy controls and patients with dementia, as well as between healthy controls and all patients, with areas under the ROC curve similar to that of the MMSE. ROC analyses with a smaller sample of 35 age-matched healthy controls showed adequate discriminant ability to detect cognitive impairment. The Nonverbal BriefScreen was shown to be a valid method for screening for cognitive impairment that could be employed as a screening method for patients with limited language.

Evidence of validity based on the relation to other variables and inter-rater reliability of the Cognitive Screening (TRIACOG) for adults with cerebrovascular diseases

This study presents evidence of validity and reliability of the results obtained with the Cognitive Screening (TRIACOG) to evaluate post-stroke adults. The TRIACOG assesses orientation memory, language, arithmetic, praxis, information processing speed, and executive functions. A total of 126 post-stroke adults (M = 63.50; SD = 13.28 years old) and 126 neurologically healthy adults (M = 61.97; SD = 11.48 years old) participated in the study. Performance on the TRIACOG was positively correlated with scores on the Montreal Cognitive Assessment-Basic (MoCA-B), schooling, and reading and writing habits, and negatively correlated with the NIHSS and Rankin scales. Post-stroke adults scored lower and took longer to complete the instrument than neurologically healthy adults. Inter-rater agreement was achieved in scoring the TRIACOG. The TRIACOG presents evidence of validity based on its relationships to other variables (criterion and convergent) and on response processes, in addition to presenting reliability evidence established by inter-rater agreement. We expect that the TRIACOG will be employed by health workers in hospital settings, health units, and medical offices.

Prevalence of, and risk factors for, cognitive impairment in lacunar stroke

BACKGROUND

Small vessel disease (SVD) is associated with vascular cognitive impairment (VCI) but why VCI occurs in some, but not other patients, is uncertain. We determined the prevalence of, and risk factors for, VCI in a large cohort of patients with lacunar stroke.

METHODS

Participants with magnetic resonance imaging (MRI)-confirmed lacunar stroke were recruited in the multicenter DNA Lacunar 2 study and compared with healthy controls. A logistic regression model was used to determine which vascular risk factors and MRI parameters were independent predictors of VCI, assessed using the Brief Memory and Executive Test (BMET).

RESULTS

A total of 912 lacunar stroke patients and 425 controls were included, with mean (SD) age of 64.6 (12.26) and 64.7 (12.29) years, respectively. VCI was detected in 38.8% lacunar patients and 13.4% controls. In a logistic regression model, diabetes mellitus (odds ratio (OR) = 1.98 (95% confidence interval (CI) = 1.40-2.80), p < 0.001) and higher body mass index (BMI) (OR = 1.03 (95% CI = 1.00-1.05), p = 0.029) were independently associated with increased risk of VCI, and years of full-time education with lower risk (OR = 0.92 (95% CI = 0.86-0.99), p = 0.018). When entering both lacune count and white matter hyperintensity (WMH) in the same logistic regression model, only WMH grade was significantly associated with VCI (OR = 1.46 (95% CI = 1.24-1.72), p < 0.001).

CONCLUSION

VCI is common in lacunar stroke patients, affecting almost 40%. This prevalence suggests that it should be routinely screened for in clinical practice. Risk factors for VCI in patients with lacunar stroke include diabetes mellitus, depressive symptoms, higher BMI, and WMH severity, while education is protective.

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.

Prevalence and Predictors of Vascular Cognitive Impairment in Patients With CADASIL

BACKGROUND AND OBJECTIVES

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common monogenic form of stroke and early-onset dementia. We determined the prevalence of vascular cognitive impairment (VCI) in a group of patients with CADASIL and investigated which factors were associated with VCI risk, including clinical, genetic, and MRI parameters.

METHODS

Cognition was assessed in patients with genetically confirmed CADASIL (n = 176) and healthy controls (n = 265) (mean [SD] age 50.95 [11.35] vs 52.37 [7.93] years) using the Brief Memory and Executive Test (BMET) and the Montreal Cognitive Assessment (MoCA). VCI was defined according to previously validated cutoffs. We determined the prevalence of VCI and its associations with clinical risk factors, mutation location (epidermal growth factor-like repeats [EGFr] 1-6 vs EGFr 7-34), and MRI markers of small vessel disease.

RESULTS

VCI was more common in patients with CADASIL than in controls; 39.8 vs 10.2% on the BMET and 47.7% vs 19.6% on the MOCA. Patients with CADASIL had worse performance across all cognitive domains. A history of stroke was associated with VCI on the BMET (OR 2.12, 95% CI [1.05, 4.27] p = 0.04) and MoCA (OR 2.55 [1.21, 5.41] p = 0.01), after controlling for age and sex. There was no association of VCI with mutation site. Lacune count was the only MRI parameter independently associated with VCI on the BMET (OR: 1.63, 95% CI [1.10, 2.41], p = 0.014), after controlling for other MRI parameters. These associations persisted after controlling for education in the sensitivity analyses.

DISCUSSION

VCI is present in almost half of the patients with CADASIL with a mean age of 50 years. Stroke and lacune count on MRI were both independent predictors of VCI on the BMET.

Systematic Review of the Psychometric Properties of the Saint Louis University Mental Status (SLUMS) Examination

OBJECTIVES

This systemic review qualitatively synthesizes existing psychometric support for the Saint Louis University Mental Status (SLUMS) Examination, a cognitive screening measure which presents as a free alternative to other widely used dementia screening measures including the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA).

METHODS

A total of 90 peer-reviewed articles on the SLUMS were identified from PsycINFO and PubMed databases.

RESULTS

Sixty-eight records were identified and reviewed by the lead author for eligibility. Studies that included at least one psychometric property of the SLUMS (n = 20) were included in this review.

CONCLUSIONS

Support for the SLUMS remains preliminary; however, it appears to have adequate validity, and adequate sensitivity and specificity in detecting cognitive impairment. Numerous shortcomings were identified, including lack of sufficient normative data, information on test-reliability, explored factor structure, and limited application of criterion measures (e.g., imaging studies, biomarkers). Research is needed to establish diverse normative samples and describe the reliability and validity of the SLUMS to strengthen the empirical support for its use.

CLINICAL IMPLICATIONS

Until its psychometric properties are better established the SLUMS should be used cautiously when screening for cognitive impairment.

The montreal cognitive assessment and mini-mental state examination visuoexecutive subtests in acute ischemic stroke patients and their correlations with demographic and clinical factors

Visuoexecutive impairment is common among acute ischemic stroke patients. This study aimed to examine the ability of the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) visuoexecutive subtests to detect visuoexecutive abnormality in acute ischemic stroke patients and to identify the predictors for their impairments. 336 patients who completed the MMSE and MoCA were enrolled in this study. We compared the proportion of participants with incorrect MoCA visuoexecutive tasks and MMSE pentagon copying. Multivariate logistic regression analysis was used to evaluate the associations between the visuoexecutive dysfunction and demographic and clinical characteristics in the samples. Among all the participants, the MoCA detected more visuoexecutive dysfunction than the MMSE (88.69% vs. 45.83%, respectively; p < 0.001). The predictors identified by the univariate analysis included the factors of gender, age, educational level, smoking, alcohol consumption, Oxfordshire Community Stroke Project (OCSP), previous strokes, initial NIHSS score and number of old lacunar infarctions, while from the multivariate logistic regression analysis, the factors of age, educational level, NIHSS score, previous strokes and number of old lacunar infarctions served as predictive factors for the visuoexecutive impairment in acute stroke patients. In conclusion, visuoexecutive impairment is associated with the factors of the educational level, stroke severity, stroke history and number of old lacunar infarctions. Our findings may guide the clinicians to intervene the risks for the patients at an early stage after stroke and form the basis for good rehabilitation plans.

Frequency and profile of objective cognitive deficits in hospitalized patients recovering from COVID-19

Early reports and case series suggest cognitive deficits occurs in some patients with COVID-19. We evaluated the frequency, severity, and profile of cognitive dysfunction in patients recovering from prolonged COVID-19 hospitalization who required acute inpatient rehabilitation prior to discharge. We analyzed cross-sectional scores from the Brief Memory and Executive Test (BMET) in a cohort of N = 57 COVID-19 patients undergoing inpatient rehabilitation, calculating the frequency of impairment based on neuropsychologist diagnosis and by age-normed BMET subtests. In total, 43 patients (75%) were male, 35 (61%) were non-white, and mean age was 64.5 (SD = 13.9) years. In total, 48 (84%) were previously living at home independently. Two patients had documented preexisting cognitive dysfunction; none had known dementia. Patients were evaluated at a mean of 43.2 (SD = 19.2) days after initial admission. In total, 50 patients (88%) had documented hypoxemic respiratory failure and 44 (77%) required intubation.  Forty-six patients (81%) had cognitive impairment, ranging from mild to severe. Deficits were common in working memory (26/47 [55%] of patients), set-shifting (21/44 [47%]), divided attention (18/39 [46%]), and processing speed (14/35 [40%]). Executive dysfunction was not significantly associated with intubation length or the time from extubation to assessment, psychiatric diagnosis, or preexisting cardiovascular/metabolic disease. Attention and executive functions are frequently impaired in COVID-19 patients who require acute rehabilitation prior to discharge. Though interpretation is limited by lack of a comparator group, these results provide an early benchmark for identifying and characterizing cognitive difficulties after COVID-19. Given the frequency and pattern of impairment, easy-to-disseminate interventions that target attention and executive dysfunctions may be beneficial to this population.

Cognitive assessment scale for stroke patients (CASP): A multicentric validation study

BACKGROUND

The Mini Mental State Examination and Montreal Cognitive Assessment are commonly used as short screening batteries for assessing cognitive impairment after stroke. However, aphasia or hemispatial neglect may interfere with the results. For this reason, we developed the Cognitive Assessment scale for Stroke Patients (CASP), which takes these conditions into consideration and previously demonstrated its superiority over these scales in terms of feasibility.

OBJECTIVES

Our goal was to verify the psychometric properties of the (original) French version of the CASP.

METHODS

We included 201 patients with a recent first hemispheric stroke and 50 controls. Stroke patients were examined 4 times (visit 1 [V1] to visit 4 [V4]) in the subacute post-stroke phase. The structural validity of the CASP was studied by principal factorial analysis, convergent validity by comparison with several variables including a comprehensive neuropsychological assessment, divergent validity by comparison with the total score between stroke patients and controls, and sub-scores between right and left stroke. Internal consistency, reproducibility and sensitivity to change were assessed. We propose the Minimal Clinically Important Difference (MCID) value and a pathological threshold as well as a threshold to predict cognitive change between V1 and V4.

RESULTS

Of the 201 participants included (63% male; mean [SD] age 63 [13] years), CASP data were available for 199/150/133/93 at V1/V2/V3/V4, respectively. CASP has a one-dimensional structure. The hypotheses of convergent/divergent validities were confirmed. Internal consistency was good and reliability excellent. Responsiveness was small to moderate, but the MCID could still be estimated. We discuss the choice of a pathological threshold and a predictive threshold of V1 over V4.

CONCLUSIONS

CASP has good psychometric properties for screening cognitive impairment in the subacute post-stroke phase, which is consistent with its Italian and Korean versions. It can be used for patients with severe motor aphasia or left hemispatial neglect but not in case of severe oral comprehension or visual impairment.

Sex Differences in Cerebral Small Vessel Disease: A Systematic Review and Meta-Analysis

Background: Cerebral small vessel disease (SVD) is a common cause of stroke, mild cognitive impairment, dementia and physical impairments. Differences in SVD incidence or severity between males and females are unknown. We assessed sex differences in SVD by assessing the male-to-female ratio (M:F) of recruited participants and incidence of SVD, risk factor presence, distribution, and severity of SVD features. Methods: We assessed four recent systematic reviews on SVD and performed a supplementary search of MEDLINE to identify studies reporting M:F ratio in covert, stroke, or cognitive SVD presentations (registered protocol: CRD42020193995). We meta-analyzed differences in sex ratios across time, countries, SVD severity and presentations, age and risk factors for SVD. Results: Amongst 123 relevant studies (n = 36,910 participants) including 53 community-based, 67 hospital-based and three mixed studies published between 1989 and 2020, more males were recruited in hospital-based than in community-based studies [M:F = 1.16 (0.70) vs. M:F = 0.79 (0.35), respectively; p < 0.001]. More males had moderate to severe SVD [M:F = 1.08 (0.81) vs. M:F = 0.82 (0.47) in healthy to mild SVD; p < 0.001], and stroke presentations where M:F was 1.67 (0.53). M:F did not differ for recent (2015-2020) vs. pre-2015 publications, by geographical region, or age. There were insufficient sex-stratified data to explore M:F and risk factors for SVD. Conclusions: Our results highlight differences in male-to-female ratios in SVD severity and amongst those presenting with stroke that have important clinical and translational implications. Future SVD research should report participant demographics, risk factors and outcomes separately for males and females. Systematic Review Registration: [PROSPERO], identifier [CRD42020193995].

Cognitive impact of cerebral microbleeds in patients with symptomatic small vessel disease

BACKGROUND AND AIM

Whether cerebral microbleeds cause cognitive impairment remains uncertain. We analyzed whether cerebral microbleeds are associated with cognitive dysfunction in patients with symptomatic cerebral small vessel disease, and whether this association is independent of other neuroimaging markers of cerebral small vessel disease.

METHODS

We analyzed consecutive patients with MRI-confirmed lacunar stroke included in DNA-Lacunar-2 multicenter study. Cerebral microbleeds were graded using the Brain Observer Microbleed Rating Scale (BOMBS). Neuropsychological assessment was performed using the Brief Memory and Executive Test (BMET). We analyzed the association between cerebral microbleeds, BMET, and the following subdomains: executive function/processing speed and orientation/memory. We also searched for an independent association between cerebral microbleeds and vascular cognitive impairment, defined as BMET ≤ 13.

RESULTS

Out of 688 included patients, cerebral microbleeds were detected in 192 (27.9%). After adjusting for white matter hyperintensities severity, lacune count, and other confounders, both the presence and the number of cerebral microbleeds were significantly associated with impaired cognitive performance [β = -13.0; 95% CI = (-25.3, -0.6) and β = -13.1; 95% CI = (-19.8, -6.4), respectively]. On analysis of specific cognitive domains, associations were present for executive function/processing speed [β = -5.8; 95% CI = (-9.3, -2.2) and β = -4.3; 95% CI = (-6.2, -2.4), respectively] but not for orientation/memory [β = -0.4; 95% CI = (-4.0, 3.2) and β = -2.1; 95% CI = (-4.0, 0.1), respectively]. We also found an independent association between the presence and the number of cerebral microbleeds and vascular cognitive impairment [adjusted OR = 1.48; 95% CI = (1.01, 2.18) and OR = 1.43; 95% CI = (1.15, 1.79), respectively].

CONCLUSION

In a large cohort of symptomatic cerebral small vessel disease patients, after controlling for other neuroimaging markers of cerebral small vessel disease severity, cerebral microbleeds were associated with cognitive dysfunction. Executive function and processing speed were predominantly impaired. This might suggest a causal role of cerebral microbleeds in determining vascular cognitive impairment.

Cognitive impairment in sporadic cerebral small vessel disease: A systematic review and meta-analysis

This paper is a proposal for an update on the characterization of cognitive impairments associated with sporadic cerebral small vessel disease (SVD). We pose a series of questions about the nature of SVD-related cognitive impairments and provide answers based on a comprehensive review and meta-analysis of published data from 69 studies. Although SVD is thought primarily to affect executive function and processing speed, we hypothesize that SVD affects all major domains of cognitive ability. We also identify low levels of education as a potentially modifiable risk factor for SVD-related cognitive impairment. Therefore, we propose the use of comprehensive cognitive assessments and the measurement of educational level both in clinics and research settings, and suggest several recommendations for future research.

A Virtual Reality-Based Screening Test for Cognitive Impairment in Small Vessel Disease

Background:

There is a need for new practical tools to assess the cognitive impairment of small vessel disease (SVD) patients in the clinic.

Objective:

This study aimed to examine cognitive functioning by administering the Virtual Supermarket (VST) in patients with SVD with cognitive impairment (SVD-CI, N = 32), cognitively normal SVD (SVD-CN, N = 37), and age-and education-matched healthy controls (HC, N = 30).

Methods:

The tablet-based VST application and comprehensive traditional pencil-and-paper neuropsychological tests assessing memory, attention, executive function, visuospatial function, and language were administered to all participants.

Results:

A moderate correlation was found between the “Duration” and “Correct Quantities” variables of VST and visuospatial function and general cognitive status composite Z scores across SVD-CI patients. “Duration” and “Correct Money” variables were moderately related to memory, executive functions, and visuospatial function composite Z scores across SVD-CN patients. A combination of all VST variables discriminated SVD-CI and HC with a correct classification rate of 81%, a sensitivity of 78%, and a specificity of 84%.

Conclusion:

This study is the first to evaluate cognitive functions employing the VST in SVD with and without cognitive impairment. It provides encouraging preliminary findings of the utility of the VST as a screening tool in the assessment of cognitive impairment and the differentiation of SVD patients from HC. In the future, validation studies of the VST with larger samples are needed.

Neuropsychological functioning in severe acute respiratory disorders caused by the coronavirus: Implications for the current COVID-19 pandemic

Objective: The coronavirus class of respiratory viruses - including Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19) - has been associated with central nervous system (CNS) disease. In fact, multiple mechanisms of CNS involvement have been proposed, making it difficult to identify a unitary syndrome that can be the focus of clinical work and research. Neuropsychologists need to understand the potential cognitive and psychological sequelae of COVID-19 and the impact of the interventions (e.g., ICU, ventilation) that have been used in treating patients with severe forms of the illness.Method: We briefly review the literature regarding the neurological and neuropsychological effects of similar coronaviruses, the limited information that has been published to date on COVID-19, and the literature regarding the long-term cognitive and psychological effects of undergoing treatment in the intensive care unit (ICU).Results: We discuss the roles that neuropsychologists can play in assessing and treating the cognitive difficulties and psychiatric symptoms described.Conclusions: At this time, the mechanisms, correlates, and effects of COVID-19 are poorly understood, but information gleaned from the literature on similar viruses and utilized interventions should help inform neuropsychologists as they begin to work with this population.

Psychometric properties of cognitive screening for patients with cerebrovascular diseases A systematic review

Screening instruments are ideal for acute clinical settings because they are easy to apply, fast, inexpensive and sensitive for specific samples. However, there is a need to verify the psychometric properties of screening in stroke patients.

Objective

This study investigated the psychometric properties (methodological procedures) of cognitive screening for patients with cerebrovascular diseases.

Methods

A systematic review of papers published on PsycINFO, Web of Knowledge, PubMed and Science Direct (2005 to 2016) was performed.

Results

A total of 55 articles remained after applying exclusion criteria. The samples ranged from 20 to 657 patients. Most articles evaluated elderly individuals with four to 13 years of education who had experienced ischemic or hemorrhagic stroke. There was a tendency to find evidence of validity for criteria and to analyze the sensitivity/specificity of the instruments. Although the studies frequently used the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) to seek evidence of validity and reliability, the use of these instruments among stroke patients has been criticized due to their psychometric properties and the neuropsychological functions evaluated.

Conclusion

Although there is no gold standard screen for assessing adults post-stroke, instruments devised specifically for this population have shown promise. This review helps both researchers and clinicians to select the most appropriate screen for identifying cognitive impairment in adults post-stroke.

MRI Lesion Load of Cerebral Small Vessel Disease and Cognitive Impairment in Patients With CADASIL

Background and objective: Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the best known and the most common monogenic small vessel disease (SVD). Cognitive impairment is an inevitable feature of CADASIL. Total SVD score and global cortical atrophy (GCA) scale were found to be good predictors of poor cognitive performance in community-dwelling adults. We aimed to estimate the association between the total SVD score, GCA scale and the cognitive performance in patients with CADASIL. Methods: We enrolled 20 genetically confirmed CADASIL patients and 20 controls matched by age, gender, and years of education. All participants underwent cognitive assessments to rate the global cognition and individual domain of executive function, information processing speed, memory, language, and visuospatial function. The total SVD score and GCA scale were rated. Results: The CADASIL group performed worse than the controls on all cognition measures. Neither global cognition nor any separate domain of cognition was significantly different among patients grouped by total SVD score. Negative correlations between the GCA score and cognitive performance were observed. Approximately 40% of the variance was explained by the total GCA score in the domains of executive function, information processing speed, and language. The superficial atrophy score was associated with poor performance in most of the domains of cognition. Adding the superficial atrophy score decreased the prediction power of the deep atrophy score on cognitive impairment alone. Conclusions: The GCA score, not the total SVD score, was significantly associated with poor cognitive performance in patients with CADASIL. Adding the superficial atrophy score attenuated the prediction power of the deep atrophy score on cognitive impairment alone.

The SNP43 (G/A) polymorphism in CAPN10 gene confers an increased risk of cognitive impairment in cerebral small vessel disease

BACKGROUND

Cognitive impairment, significantly reducing processing speed and executive function, is the critical consequence of cerebral small vessel disease (SVD), in which genetic variations have been studied. In this study, we explore the role of SNP43 (G/A) and SNP63 (C/T) polymorphism in the CAPN10 on cognitive impairment process in cerebral SVD.

METHODS

Cerebral SVD patients (n = 224) and healthy controls (n = 187) were recruited. The relationship between frequency distribution of SNP43 (G/A) and SNP63 (T/C) genotype and allele in CAPN10 gene, and cognitive impairment was examined. The independent risk factors for cognitive impairment in SVD were determined by logistic regression analysis.

RESULTS

Accordingly, the frequency distribution of genotype and allele at SNP43 (G/A) was significantly different between cerebral SVD patients and healthy controls. Cerebral SVD patients with GG genotype were more susceptible for cognitive impairment, whereas cerebral SVD patients with GA + AA genotype were less possible to suffer from cognitive impairment, compared with those with GG genotype. And also, cerebral SVD does not include SNP63 (C/T) to associate with cognitive impairment, and SNP43 (G/A), total cholesterol, triglyceride, low-density lipoprotein, and high-density lipoprotein were independent risk factors for cognitive impairment in SVD.

CONCLUSION

Our study provides evidence that SNP43 (G/A) in the CAPN10 gene increases the risk of cognitive impairment in SVD patients. Besides it is proven that, patients with G allele are more susceptible to suffer from cerebral SVD with worse cognitive impairment.

The Brief Memory and Executive Test (BMET): A cognitive screening tool to detect and differentiate vascular cognitive impairment and Alzheimer's disease

OBJECTIVE

While there are several cognitive screening tests available for the detection of cortical dementias such as Alzheimer's disease (AD), these are rarely designed to be sensitive to vascular cognitive impairment (VCI). The Brief Memory and Executive Test (BMET) is a screening measure designed to be sensitive to the cognitive profile of both VCI and AD. This study investigated the ability of the BMET to detect AD, and to differentiate between VCI and AD.

METHODS

This study included 150 patients, with either SVD, both with (n = 48) and without VCI (n = 51), or AD (N = 51) and 51 healthy controls. Participants were aged between 40 and 90 years of age and completed both the BMET and the MMSE.

RESULTS

Receiver operator characteristic (ROC) curve analysis showed as before the BMET is a good predictor SVD. Additionally, the BMET was a good predictor of AD (AUC = 0.96) and performed at least as well as the MMSE (AUC = 0.92) when differentiating AD patients from healthy controls. The BMET had a sensitivity of 86% and specificity of 100% for detecting AD patients from control subjects. Using the difference in cognitive profile between the AD and VCI group, we developed an index score which correctly classified 76% of patients as either having VCI or AD.

CONCLUSION

The BMET is a brief and sensitive tool for the detection of cognitive impairment due to both SVD and AD and can be used to aid in the differentiation of the 2 diseases.

The effect of phosphodiesterase-5 inhibitors on cerebral blood flow in humans: A systematic review

Agents that augment cerebral blood flow (CBF) could be potential treatments for vascular cognitive impairment. Phosphodiesterase-5 inhibitors are vasodilating drugs established in the treatment of erectile dysfunction (ED) and pulmonary hypertension. We reviewed published data on the effects of phosphodiesterase-5 inhibitors on CBF in adult humans. A systematic review according to PRISMA guidelines was performed. Embase, Medline and Cochrane Library Trials databases were searched. Sixteen studies with 353 participants in total were retrieved. Studies included healthy volunteers and patients with migraine, ED, type 2 diabetes, stroke, pulmonary hypertension, Becker muscular dystrophy and subarachnoid haemorrhage. Most studies used middle cerebral artery flow velocity to estimate CBF. Few studies employed direct measurements of tissue perfusion. Resting CBF velocity was unaffected by phosphodiesterase-5 inhibitors, but cerebrovascular regulation was improved in ED, pulmonary hypertension, diabetes, Becker's and a group of healthy volunteers. This evidence suggests that phosphodiesterase-5 inhibitors improve responsiveness of the cerebral vasculature, particularly in disease states associated with an impaired endothelial dilatory response. This supports the potential therapeutic use of phosphodiesterase-5 inhibitors in vascular cognitive impairment where CBF is reduced. Further studies with better resolution of deep CBF are warranted. The review is registered on the PROSPERO database (registration number CRD42016029668).

Update on Vascular Cognitive Impairment Associated with Subcortical Small-Vessel Disease

Subcortical small-vessel disease (SSVD) is a disorder well characterized from the clinical, imaging, and neuropathological viewpoints. SSVD is considered the most prevalent ischemic brain disorder, increasing in frequency with age. Vascular risk factors include hypertension, diabetes, hyperlipidemia, elevated homocysteine, and obstructive sleep apnea. Ischemic white matter lesions are the hallmark of SSVD; other pathological lesions include arteriolosclerosis, dilatation of perivascular spaces, venous collagenosis, cerebral amyloid angiopathy, microbleeds, microinfarcts, lacunes, and large infarcts. The pathogenesis of SSVD is incompletely understood but includes endothelial changes and blood-brain barrier alterations involving metalloproteinases, vascular endothelial growth factors, angiotensin II, mindin/spondin, and the mammalian target of rapamycin pathway. Metabolic and genetic conditions may also play a role but hitherto there are few conclusive studies. Clinical diagnosis of SSVD includes early executive dysfunction manifested by impaired capacity to use complex information, to formulate strategies, and to exercise self-control. In comparison with Alzheimer's disease (AD), patients with SSVD show less pronounced episodic memory deficits. Brain imaging has advanced substantially the diagnostic tools for SSVD. With the exception of cortical microinfarcts, all other lesions are well visualized with MRI. Diagnostic biomarkers that separate AD from SSVD include reduction of cerebrospinal fluid amyloid-β (Aβ)42 and of the ratio Aβ42/Aβ40 often with increased total tau levels. However, better markers of small-vessel function of intracerebral blood vessels are needed. The treatment of SSVD remains unsatisfactory other than control of vascular risk factors. There is an urgent need of finding targets to slow down and potentially halt the progression of this prevalent, but often unrecognized, disorder.

A continuum of executive function deficits in early subcortical vascular cognitive impairment: A systematic review and meta-analysis

BACKGROUND

Subcortical Vascular Cognitive Impairment (SVCI) is a clinical continuum of vascular-related cognitive impairment, including Vascular Mild Cognitive Impairment (VaMCI) and Vascular Dementia. Deficits in Executive Function (EF) are hallmarks of the disorder, but the best methods to assess this function have yet to be determined. The insidious and almost predictable course of SVCI and the multidimensional concept of EF suggest that a temporal dissociation of impairments in EF domains exists early in the disorder.

OBJECTIVE

This study aims to review and analyze data from the literature about performance of VaMCI patients on the most used EF tests through a meta-analytic approach.

METHODS

Medline, Web of Knowledge and PsycINFO were searched, using the terms: "vascular mild cognitive impairment" OR "vascular cognitive impairment no dementia" OR "vascular mild neurocognitive disorder" AND "dysexecutive" OR "executive function". Meta-analyses were conducted for each of the selected tests, using random-effect models.

RESULTS

Systematic review showed major discrepancies among the results of the studies included. Meta-analyses evidenced poorer performance on the Trail-Making Test part B and the Stroop color test by VaMCI patients compared to controls.

CONCLUSION

A continuum of EF impairments has been proposed in SVCI. Early deficits appear to occur in cognitive flexibility and inhibitory control.

Mnemonic function in small vessel disease and associations with white matter tract microstructure

Cerebral small vessel disease (SVD) is associated with deficits in working memory, with a relative sparing of long-term memory; function may be influenced by white matter microstructure. Working and long-term memory were examined in 106 patients with SVD and 35 healthy controls. Microstructure was measured in the uncinate fasciculi and cingula. Working memory was more impaired than long-term memory in SVD, but both abilities were reduced compared to controls. Regression analyses found that having SVD explained the variance in memory functions, with additional variance explained by the cingula (working memory) and uncinate (long-term memory). Performance can be explained in terms of integrity loss in specific white matter tract associated with mnemonic functions.

Apathy, but not depression, is associated with executive dysfunction in cerebral small vessel disease

Objective

To determine the prevalence of apathy and depression in cerebral small vessel disease (SVD), and the relationships between both apathy and depression with cognition. To examine whether apathy is specifically related to impairment in executive functioning and processing speed.

Methods

196 patients with a clinical lacunar stroke and an anatomically corresponding lacunar infarct on MRI were compared to 300 stroke-free controls. Apathy and depression were measured using the Geriatric Depression Scale, and cognitive functioning was assessed using an SVD cognitive screening tool, the Brief Memory and Executive Test, which measures executive functioning/processing speed and memory/orientation. Path analysis and binary logistic regression were used to assess the relation between apathy, depression and cognitive impairment.

Results

31 participants with SVD (15.8%) met criteria for apathy only, 23 (11.8%) for both apathy and depression, and 2 (1.0%) for depression only. In the SVD group the presence of apathy was related to global cognition, and specifically to impaired executive functioning/processing speed, but not memory/orientation. The presence of depression was not related to global cognition, impaired executive functioning/processing speed or memory/orientation.

Conclusions

Apathy is a common feature of SVD and is associated with impaired executive functioning/processing speed suggesting the two may share biological mechanisms. Screening for apathy should be considered in SVD, and further work is required to develop and evaluate effective apathy treatment or management in SVD.

Early-onset and delayed-onset poststroke dementia - revisiting the mechanisms

Incident stroke has long been recognized to cause dementia shortly after the event. Patients who survive stroke without early-onset poststroke dementia (PSD) are at a high risk of developing dementia months to years after the initial stroke incident, which has generated enthusiasm for exploring treatments to prevent delayed-onset PSD in survivors of stroke. However, results from clinical trials completed in the past 10-15 years have been disappointing. In light of these results, the present Review revisits the mechanisms of both early-onset and delayed-onset PSD and proposes preventive strategies and directions for future clinical trials. Early-onset PSD results from a complex interplay between stroke lesion features and brain resilience, whereas delayed-onset PSD is associated mainly with the presence of severe sporadic small vessel disease (SVD), and to a lesser extent with Alzheimer disease pathology or recurrent stroke. As well as preventing stroke and delivering acute stroke treatments to reduce initial brain damage, measures to increase brain resilience could also reduce the risk of developing dementia if an incident stroke occurs. Future efforts to prevent delayed-onset PSD should focus on the study of sporadic SVD and on evaluating whether other strategies, in addition to conventional secondary stroke prevention, are effective in dementia prevention in this high-risk group.

Brief Screening of Vascular Cognitive Impairment in Patients With Cerebral Autosomal-Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy Without Dementia

BACKGROUND AND PURPOSE

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic form of cerebral small vessel disease leading to early-onset stroke and dementia, with younger patients frequently showing subclinical deficits in cognition. At present, there are no targeted cognitive screening measures for this population. However, the Brief Memory and Executive Test (BMET) and the Montreal Cognitive Assessment (MoCA) have shown utility in detecting cognitive impairment in sporadic small vessel disease. This study assesses the BMET and the MoCA as clinical tools for detecting mild cognitive deficits in CADASIL.

METHODS

Sixty-six prospectively recruited patients with CADASIL, and 66 matched controls completed the BMET, with a subset of these also completing the MoCA. Receiver operating characteristic curves were calculated to examine the sensitivity and specificity of clinical cutoffs for the detection of vascular cognitive impairment and reduced activities of daily living.

RESULTS

Patients with CADASIL showed more cognitive impairment overall and were poorer on both executive/processing and memory indices of the BMET relative to controls. The BMET showed good accuracy in predicting vascular cognitive impairment (85% sensitivity and 84% specificity) and impaired instrumental activities of daily living (92% sensitivity and 77% specificity). The MoCA also showed good predictive validity for vascular cognitive impairment (80% sensitivity and 78% specificity) and instrumental activities of daily living (75% sensitivity and 76% specificity). The most important background predictor of vascular cognitive impairment was a history of stroke.

CONCLUSIONS

The results indicate that the BMET and the MoCA are clinically useful and sensitive screening measures for early cognitive impairment in patients with CADASIL.

Associations between the Brief Memory and Executive Test (BMET), Activities of Daily Living, and Quality of Life in Patients with Cerebral Small Vessel Disease

OBJECTIVES

In addition to neuropsychological difficulties, patients with cerebral small vessel disease (SVD) can have reduced activities of daily living and a poorer quality of life compared to healthy adults. The Brief Memory and Executive Test (BMET), is a cognitive screening tool designed to be sensitive to the neuropsychological profile of patients with SVD. While the BMET is sensitive to the cognitive consequences of SVD, it is unclear how well scores on this measure relate to functional outcomes. The aims of this study are to investigate the relationship between scores on the BMET and functional outcomes (activities of daily living and quality of life) in SVD, and to compare this with other commonly used cognitive screening tools.

METHODS

This study included 184 participants with SVD (mean age=63.2; SD=9.9) and 299 healthy controls (mean age=62.4; SD=13.8) who were tested using the BMET, Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), Stroke Specific - Quality of Life Scale (SS-QoL), Geriatric Depression Scale (GDS), and measures of both instrumental activities of daily living (IADL) and basic activities of daily living (BADL).

RESULTS

After controlling for covariates the scores on the BMET, but not the MoCA or MMSE, were significantly related to poorer IADL and quality of life in the SVD group. In addition to the BMET scores, symptoms of depression were found to be significant associated with functional outcome.

CONCLUSION

These results support the clinical utility of using of the BMET, in combination with a standardized depression questionnaire, during the early assessment of patients with SVD.

Neuroimaging criteria and cognitive performance in vascular mild cognitive impairment: A systematic review

The recognition of Cerebrovascular Disease (CVD) at earlier clinical stages may favor the control of vascular risk factors and prevention of dementia. However, operational criteria for symptomatic phases at non-dementia stages are often difficult, as the current criteria normally require the evidence of extensive subcortical disease.

Differential relationships between apathy and depression with white matter microstructural changes and functional outcomes

Small vessel disease is a stroke subtype characterized by pathology of the small perforating arteries, which supply the sub-cortical structures of the brain. Small vessel disease is associated with high rates of apathy and depression, thought to be caused by a disruption of white matter cortical-subcortical pathways important for emotion regulation. It provides an important biological model to investigate mechanisms underlying these key neuropsychiatric disorders. This study investigated whether apathy and depression can be distinguished in small vessel disease both in terms of their relative relationship with white matter microstructure, and secondly whether they can independently predict functional outcomes. Participants with small vessel disease (n = 118; mean age = 68.9 years; 65% male) defined as a clinical and magnetic resonance imaging confirmed lacunar stroke with radiological leukoaraiosis were recruited and completed cognitive testing, measures of apathy, depression, quality of life and diffusion tensor imaging. Healthy controls (n = 398; mean age = 64.3 years; 52% male) were also studied in order to interpret the degree of apathy and depression found within the small vessel disease group. Firstly, a multilevel structural equation modelling approach was used to identify: (i) the relationships between median fractional anisotropy and apathy, depression and cognitive impairment; and (ii) if apathy and depression make independent contributions to quality of life in patients with small vessel disease. Secondly, we applied a whole-brain voxel-based analysis to investigate which regions of white matter were associated with apathy and depression, controlling for age, gender and cognitive functioning. Structural equation modelling results indicated both apathy (r = -0.23, P ≤ 0.001) and depression (r = -0.41, P ≤ 0.001) were independent predictors of quality of life. A reduced median fractional anisotropy was significantly associated with apathy (r = -0.38, P ≤ 0.001), but not depression (r = -0.16, P = 0.09). On voxel-based analysis, apathy was associated with widespread reduction in white matter integrity, with the strongest effects in limbic association tracts such as the anterior cingulum, fornix and uncinate fasciculus. In contrast, when controlling for apathy, we found no significant relationship between our white matter parameters and symptoms of depression. In conclusion, white matter microstructural changes in small vessel disease are associated with apathy but not directly with depressive symptoms. These results suggest that apathy, but not depression, in small vessel disease is related to damage to cortical-subcortical networks associated with emotion regulation, reward and goal-directed behaviour.