Classification and subtypes of vascular dementia

Comparing survival and mortality in patients with late-onset and young-onset vascular dementia

OBJECTIVES

Vascular dementia (VD) is one of the more common types of dementia. Much is known about VD in older adults in terms of survival and associated risk factors, but comparatively less is known about VD in a younger population. This study aimed to investigate survival in people with young-onset VD (YO-VD) compared to those with late-onset VD (LO-VD) and to investigate predictors of mortality.

DESIGN

Retrospective file review from 1992 to 2014.

SETTING

The inpatient unit of a tertiary neuropsychiatry service in Victoria, Australia.

PARTICIPANTS

Inpatients with a diagnosis of VD.

MEASUREMENTS AND METHODS

Mortality information was obtained from the Australian Institute of Health and Welfare. Clinical variables included age of onset, sex, vascular risk factors, structural neuroimaging, and Hachinksi scores. Statistical analyses used were Kaplan-Meier curves for median survival and Cox regression for predictors of mortality.

RESULTS

Eighty-four participants were included with few clinical differences between the LO-VD and YO-VD groups. Sixty-eight (81%) had died. Median survival was 9.9 years (95% confidence interval 7.9, 11.7), with those with LO-VD having significantly shorter survival compared to those with YO-VD (6.1 years and 12.8 years, respectively) and proportionally more with LO-VD had died (94.6%) compared to those with YO-VD (67.5%), χ2(1) = 9.16, p = 0.002. The only significant predictor of mortality was increasing age (p = 0.001).

CONCLUSION

While there were few clinical differences, and older age was the only factor associated with survival, further research into the effects of managing cardiovascular risk factors and their impact on survival are recommended.

Vascular Dementia and Underlying Sex Differences

Vascular dementia (VaD) is the second most common form of dementia after Alzheimer's disease (AD); where Alzheimer's accounts for 60-70% of cases of dementia and VaD accounts for 20% of all dementia cases. VaD is defined as a reduced or lack of blood flow to the brain that causes dementia. VaD is also known occasionally as vascular contributions to cognitive impairment and dementia (VCID) or multi-infarct dementia (MID). VCID is the condition arising from stroke and other vascular brain injuries that cause significant changes to memory, thinking, and behavior, and VaD is the most severe stage while MID is produced by the synergistic effects caused by multiple mini strokes in the brain irrespective of specific location or volume. There are also subtle differences in the presentation of VaD in males and females, but they are often overlooked. Since 1672 when the first case of VaD was reported until now, sex and gender differences have had little to no research done when it comes to the umbrella term of dementia in general. This review summarizes the fundamentals of VaD followed by a focus on the differences between sex and gender when an individual is diagnosed. In addition, we provide critical evidence concerning sex and gender differences with a few of the main risk factors of VaD including pre-existing health conditions and family history, gene variants, aging, hormone fluctuations, and environmental risk factors. Additionally, the pharmaceutical treatments and possible mitigation of risk factors is explored.

Small vessel disease to subcortical dementia: a dynamic model, which interfaces aging, cholinergic dysregulation and the neurovascular unit

Background

Small vessels have the pivotal role for the brain’s autoregulation. The arteriosclerosis-dependent alteration of the brain perfusion is one of the major determinants in small vessel disease. Endothelium distress can potentiate the flow dysregulation and lead to subcortical vascular dementia (sVAD). sVAD increases morbidity and disability. Epidemiological studies have shown that sVAD shares with cerebrovascular disease most of the common risk factors. The molecular basis of this pathology remains controversial.

Purpose

To detect the possible mechanisms between small vessel disease and sVAD, giving a broad vision on the topic, including pathological aspects, clinical and laboratory findings, metabolic process and cholinergic dysfunction.

Methods

We searched MEDLINE using different search terms (“vascular dementia”, “subcortical vascular dementia”, “small vessel disease”, “cholinergic afferents”, etc). Publications were selected from the past 20 years. Searches were extended to Embase, Cochrane Library, and LILIACS databases. All searches were done from January 1, 1998 up to January 31, 2018.

Results

A total of 560 studies showed up, and appropriate studies were included. Associations between traditional vascular risk factors have been isolated. We remarked that SVD and white matter abnormalities are seen frequently with aging and also that vascular and endothelium changes are related with age; the changes can be accelerated by different vascular risk factors. Vascular function changes can be heavily influenced by genetic and epigenetic factors.

Conclusion

Small vessel disease and the related dementia are two pathologies that deserve attention for their relevance and impact in clinical practice. Hypertension might be a historical problem for SVD and SVAD, but low pressure might be even more dangerous; CBF regional selective decrease seems to be a critical factor for small vessel disease-related dementia. In those patients, endothelium damage is a super-imposed condition. Several issues are still debatable, and more research is needed.

White matter hyperintensities are related to pain intensity in an outpatient memory clinic population: preliminary findings

Background: The association between pain and dementia is complicated and may depend on underlying brain pathology. It was hypothesized that both medial temporal atrophy (MTA) and global cortical atrophy (GCA) predicted no/mild pain, while white matter hyperintensities (WMH) predicted moderate/severe pain.

Objectives: To study the association between pain intensity and measures of brain pathology, more specifically MTA, GCA, and WMH.

Methods: In total, 115 consecutive patients visiting an outpatient memory clinic were included. In total, diagnoses included dementia (N=70), mild cognitive impairment (N=30), and subjective cognitive impairment (N=15). Without administering stimuli, pain intensity was assessed with the Brief Pain Inventory. MTA, GCA, and WMH were measured with a MRI visual rating scale. Logistic regression analyses to examine the relationship between WMH, MTA, GCA, and self-reported pain intensity (no/mild pain versus moderate/severe pain) were adjusted for confounders.

Results: Mean age of the patients was 81 years (IQR: 78–85, 53% female). Moderate/severe pain was reported by 23.5% and associated with greater WMH (OR =3.34, 95% CI =1.01–10.97, p=0.047), but not MTA or GCA.

Conclusions: In contrast to the present results, earlier studies have reported either a positive or negative relationship between pain and brain volume. It is suggested that the presence of dementia may explain the absence of a relationship between pain and brain volume. WMH is positively related with pain in an older memory outpatient population. Considering the small sample size, our findings should be interpreted with caution. Hence, our conclusions are preliminary findings, warranting future replication.

Prevalence of Mild Cognitive Impairment and Its Subtypes among Chinese Older Adults: Role of Vascular Risk Factors

BACKGROUND/AIMS

The prevalence of mild cognitive impairment (MCI) and its subtypes among Chinese older adults, and the contribution of vascular risk factors (VRF) and vascular disorders to MCI remain unclear. This study aims to investigate the prevalence of MCI and its different subtypes, and clarify the role of VRF and vascular diseases in the occurrence of MCI.

METHODS

A random sample of 5,214 nondementia (DSM-IV) individuals aged ≥65 years underwent neuropsychological assessments and clinical examinations. MCI, including amnestic MCI-single domain (aMCI-SD), amnestic MCI-multiple domains (aMCI-MD), nonamnestic MCI-single domain (naMCI-SD), and nonamnestic MCI-multiple domains (naMCI-MD), was defined according to modifications of the Petersen criteria. VRF (smoking, obesity, and diabetes) and vascular disorders (myocardial infarction, atrial xFB01;brillation, stroke, and hypertension) were assessed based on information through self-report and medical records. Data were analyzed using multivariate logistic regression.

RESULTS

The prevalence of MCI was 11.33% (95% CI: 8.21-14.43), and that of aMCI-SD, aMCI-MD, naMCI-SD, and naMCI-MD was 4.48% (95% CI: 2.24-6.74), 2.09% (95% CI: 0.80-3.38), 4.22% (95% CI: 1.38-7.08), and 0.53% (95% CI: 0.32-0.75), respectively. The prevalence of MCI is higher in women than in men. Multivariate logistic regression analysis shows that VRF and vascular diseases were significantly related to increase the odds of MCI and its specific subtype.

CONCLUSIONS

The prevalence of MCI is almost 11% among Chinese older adults. VRF and vascular disorders are associated with MCI, especially naMCI.

Toll-like Receptor 2: A Novel Therapeutic Target for Ischemic White Matter Injury and Oligodendrocyte Death

Despite paramount clinical significance of white matter stroke, there is a paucity of researches on the pathomechanism of ischemic white matter damage and accompanying oligodendrocyte (OL) death. Therefore, a large gap exists between clinical needs and laboratory researches in this disease entity. Recent works have started to elucidate cellular and molecular basis of white matter injury under ischemic stress. In this paper, we briefly introduce white matter stroke from a clinical point of view and review pathophysiology of ischemic white matter injury characterized by OL death and demyelination. We present a series of evidence that Toll-like receptor 2 (TLR2), one of the membranous pattern recognition receptors, plays a cell-autonomous protective role in ischemic OL death and ensuing demyelination. Moreover, we also discuss our recent findings that its endogenous ligand, high-mobility group box 1 (HMGB1), is released from dying OLs and exerts autocrine trophic effects on OLs and myelin sheath under ischemic condition. We propose that modulation of TLR2 and its endogenous ligand HMGB1 can be a novel therapeutic target for ischemic white matter disease.

Color perception differentiates Alzheimer's Disease (AD) from Vascular Dementia (VaD) patients

BACKGROUND

Alzheimer's Disease (AD) and Vascular Dementia (VaD) are the most common causes of dementia in older people. Both diseases appear to have similar clinical symptoms, such as deficits in attention and executive function, but specific cognitive domains are affected. Current cohort studies have shown a close relationship between αβ deposits and age-related macular degeneration (Johnson et al., 2002; Ratnayaka et al., 2015). Additionally, a close link between the thinning of the retinal nerve fiber (RNFL) and AD patients has been described, while it has been proposed that AD patients suffer from a non-specific type of color blindness (Pache et al., 2003).

METHODS

Our study included 103 individuals divided into three groups: A healthy control group (n = 35), AD (n = 32) according to DSM-IV-TR, NINCDS-ADRDA criteria, and VaD (n = 36) based on ΝΙΝDS-AIREN, as well as Magnetic Resonance Imaging (MRI) results. The severity of patient's cognitive impairment, was measured with the Mini-Mental State Examination (MMSE) and was classified according to the Reisberg global deterioration scale (GDS). Visual perception was examined using the Ishihara plates: "Ishihara Color Vision Test - 38 Plate."

RESULTS

The three groups were not statistically different for demographic data (age, gender, and education). The Ishihara color blindness test has a sensitivity of 80.6% and a specificity of 87.5% to discriminate AD and VaD patients when an optimal (32.5) cut-off value of performance is used.

CONCLUSIONS

Ishihara Color Vision Test - 38 Plate is a promising potential method as an easy and not time-consuming screening test for the differential diagnosis of dementia between AD and VaD.

Síndromes neuropsiquiátricas associadas a acidentes vasculares encefálicos: revisão de literatura

Objetivo Revisar as principais síndromes neuropsiquiátricas associadas ao acidente vascular encefálico (AVE), suas características clínicas, impacto sobre a recuperação dos pacientes, tratamento, suas possíveis relações com a fisiopatologia dos AVE e, quando possível, contextualizá-las à realidade brasileira. Métodos Foram realizadas buscas nas bases de dados PubMed/MedLine e SciELO/Lilacs com os termos “stroke” e “cerebrovascular disease” em combinações com “neuropsychiatry”, “neuropsychiatric disorders”, “psychiatry”, “psychiatric disorders”, “depression”, “anxiety” e “dementia”, com ênfase nos últimos dez anos. Resultados Foram revisadas as síndromes neuropsiquiátricas pós-AVE, incluindo depressão, ansiedade, transtorno da expressão emocional involuntária, labilidade emocional, irritabilidade, raiva, reação catastrófica, apatia, demência, mania e psicose, de acordo com os objetivos propostos. Conclusão É notória a escassez de informações sobre o manejo terapêutico das complicações neuropsiquiátricas secundárias aos AVE, especialmente diante do impacto em saúde pública representado pelas doenças cerebrovasculares. Com a evolução da abordagem precoce a esses pacientes e o consequente aumento de sua sobrevida, o aprofundamento do conhecimento sobre o desenvolvimento e o tratamento dos transtornos neuropsiquiátricos parece ter maior potencial para melhorar o desfecho e a qualidade de vida dos indivíduos que sofreram AVE.

The neglected co-star in the dementia drama: the putative roles of astrocytes in the pathogeneses of major neurocognitive disorders

Alzheimer's disease (AD) and vascular dementia are the major causes of cognitive disorders worldwide. They are characterized by cognitive impairments along with neuropsychiatric symptoms, and that their pathogeneses show overlapping multifactorial mechanisms. Although AD has long been considered the most common cause of dementia, individuals afflicted with AD commonly exhibit cerebral vascular abnormalities. The concept of mixed dementia has emerged to more clearly identify patients with neurodegenerative phenomena exhibiting both AD and cerebral vascular pathologies-vascular damage along with β-amyloid (Aβ)-associated neurotoxicity and τ-hyperphosphorylation. Cognitive impairment has long been commonly explained through a 'neuro-centric' perspective, but emerging evidence has shed light over the important roles that neurovascular unit dysfunction could have in neuronal death. Moreover, accumulating data have been demonstrating astrocytes being the essential cell type in maintaining proper central nervous system functioning. In relation to dementia, the roles of astrocytes in Aβ deposition and clearance are unclear. This article emphasizes the multiple events triggered by ischemia and the cytotoxicity exerted by Aβ either alone or in association with endothelin-1 and receptor for advanced glycation end products, thereby leading to neurodegeneration in an 'astroglio-centric' perspective.

Frontal Behavioural Inventory in the differential diagnosis of dementia

OBJECTIVE

To evaluate diagnostic properties of the Frontal Behavioural Inventory (FBI) in patients suffering from different forms of dementia.

METHODS

The FBI was administered with other psychometric tests investigating cognitive performances and behavioral scales to the caregivers of 35 patients with the frontal variant of frontotemporal dementia (fv-FTD), 22 patients with Alzheimer's disease (AD) and 15 with vascular dementia (VaD). All patients were comparable for degree of dementia severity and level of executive impairment.

RESULTS

The FBI showed high concurrent validity, internal consistency and good inter-rater and test-retest reliability. The discriminant validity was also very high. A new FBI cut-off score of 23 gave 97% sensitivity and 95% specificity in distinguishing fv-FTD from non-FTD patients. Conversely, the Neuropsychiatic Inventory (NPI) score was unable to differentiate fv-FTD from AD.

CONCLUSIONS

The FBI is a neurobehavioral tool suitable to distinguish fv-FTD from other forms of dementia also when data from cognitive testing or other behavioral scales fail to support the differential diagnosis.

Vascular risk factors in mild cognitive impairment subtypes. Findings from the ReGAl project

BACKGROUND AND AIM

To investigate the role of vascular risk factors in different subtypes of mild cognitive impairment (MCI) in a multicentric, clinic-based, cross-sectional study.

METHODS

Two-hundred and seven subjects with MCI were included in the study: 33 with single non-memory MCI (snmMCI), 42 with multiple-domain amnestic MCI (mdMCI-a) and 132 with amnestic MCI (aMCI). Several clinical vascular risk factors and magnetic resonance imaging (MRI) brain lesions were evaluated.

RESULTS

snmMCI showed a higher frequency of ischaemic heart disease and of transient ischaemic attack (TIA)/stroke, a higher Hachinski ischaemic score and a higher frequency of white-matter lesions on MRI compared to aMCI. Subjects with mdMCI-a showed clinical characteristics similar to aMCI, except for a higher frequency of a history of TIA/stroke.

CONCLUSION

Our findings suggest that snmMCI may be considered a vascular cognitive disorder.

Citicoline (Cognizin) in the treatment of cognitive impairment

Pharmacological treatment of cerebrovascular disorders was introduced at the beginning of the 20th Century. Since then, a multitude of studies have focused on the development of a consensus for a well defined taxonomy of these disorders and on the identification of specific patterns of cognitive deficits associated with them, but with no clear consensus. Nevertheless, citicoline has proved to be a valid treatment in patients with a cerebrovascular pathogenesis for memory disorders. A metanalysis performed on the entire database available from the clinical studies performed with this compound confirms the experimental evidence from the animal studies which have repeatedly described the multiple biological actions of citicoline in restoring both the cell lipid structures and some neurotransmitter functions.

Relationship between memory, attention, and depression in chronic cerebro-vascular patients

Vascular dementia patients show a component of their impairment as emotional. In the two studies that we present it was possible to illustrate the characteristics of such emotional component. a. The discrepancy between immediate recall and delayed recall appears to be very sensitive to anxiety interference when immediate recall is lower than delayed. b. The presence of emotional problems contributing to memory complaints in VaD patients is not equally distributed along the severity of deterioration dimension but can be identified as a specific component different from the cognitive one especially in that subgroup of patients who present an intermediate level of deterioration.

Small vessel disease and subcortical vascular dementia

Atherothromboembolism and intracranial small vessel disease are considered to be the main causes of cerebrovascular injury, which may lead to cognitive impairment and vascular dementia (VaD). VaD appears to be the second most common type of dementia with prevalence estimates of 10-15%. Cortical or multi-infarct dementia and subcortical vascular dementia (SVD) are suggested to be the two main forms of VaD. The main clinical features of SVD comprise decreased motor performance, early impairment of attention and executive function with slowing of information processing. SVD results from lacunar infarcts or multiple microinfarcts in the basal ganglia, thalamus, brainstem and white matter and are associated with more than 50% of the VaD cases. White matter changes including regions of incomplete infarction are usually widespread in VaD but their contribution to impairment of subcortical regions is unclear. While most of VaD occurs sporadically only a small proportion of cases bear clear familial traits. CADASIL is likely the most common form of hereditary VaD, which arises from subcortical arteriopathy. SVD needs unambiguous definition to impact on preventative and treatment strategies, and critical for selective recruitment to clinical trials.