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1.
Alzheimers Dement (Amst) ; 16(2): e12576, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605996

RESUMO

INTRODUCTION: While elevated blood glial fibrillary acidic protein (GFAP) has been associated with brain amyloid pathology, whether this association occurs in populations with high cerebral small vessel disease (CSVD) concomitance remains unclear. METHODS: Using a Singapore-based cohort of cognitively impaired subjects, we assessed associations between plasma GFAP and neuroimaging measures of brain amyloid and CSVD, including white matter hyperintensities (WMH). We also examined the diagnostic performance of plasma GFAP in detecting brain amyloid beta positivity (Aß+). RESULTS: When stratified by WMH status, elevated brain amyloid was associated with higher plasma GFAP only in the WMH- group (ß = 0.383; P < 0.001). The diagnostic performance of plasma GFAP in identifying Aß+ was significantly higher in the WMH- group (area under the curve [AUC] = 0.896) than in the WMH+ group (AUC = 0.712, P = 0.008). DISCUSSION: The biomarker utility of plasma GFAP in detecting brain amyloid pathology is dependent on the severity of concomitant WMH. Highlight: Glial fibrillary acidic protein (GFAP)'s association with brain amyloid is unclear in populations with high cerebral small vessel disease (CSVD).Plasma GFAP was measured in a cohort with CSVD and brain amyloid.Plasma GFAP was better in detecting amyloid in patients with low CSVD versus high CSVD.Biomarker utility of GFAP in detecting brain amyloid depends on the severity of CSVD.

2.
Alzheimers Dement (Amst) ; 15(1): e12396, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36994314

RESUMO

Introduction: Plasma neurofilament light chain (NfL) is a potential biomarker for neurodegeneration in Alzheimer's disease (AD), ischemic stroke, and non-dementia cohorts with cerebral small vessel disease (CSVD). However, studies of AD in populations with high prevalence of concomitant CSVD to evaluate associations of brain atrophy, CSVD, and amyloid beta (Aß) burden on plasma NfL are lacking. Methods: Associations were tested between plasma NfL and brain Aß, medial temporal lobe atrophy (MTA) as well as neuroimaging features of CSVD, including white matter hyperintensities (WMH), lacunes, and cerebral microbleeds. Results: We found that participants with either MTA (defined as MTA score ≥2; neurodegeneration [N]+WMH-) or WMH (cut-off for log-transformed WMH volume at 50th percentile; N-WMH+) manifested increased plasma NfL levels. Participants with both pathologies (N+WMH+) showed the highest NfL compared to N+WMH-, N-WMH+, and N-WMH- individuals. Discussion: Plasma NfL has potential utility in stratifying individual and combined contributions of AD pathology and CSVD to cognitive impairment.

3.
Cleft Palate Craniofac J ; 60(10): 1273-1283, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538856

RESUMO

OBJECTIVE: Objective differentiation between unilateral coronal synostosis (UCS) and positional posterior plagiocephaly (PPP) based on 3D photogrammetry according to Utrecht Cranial Shape Quantificator (UCSQ). DESIGN: Retrospective study. SETTING: Primary craniofacial center. PATIENTS, PARTICIPANTS: Thirty-two unoperated patients (17 UCS; 15 PPP) (age < 1 year). INTERVENTIONS: Extraction of variables from sinusoid curves derived using UCSQ: asymmetry ratio forehead and occiput peak, ratio of gradient forehead and occiput peak, location forehead and occiput peak. MAIN OUTCOME MEASURE(S): Variables, derived using 3D photogrammetry, were analyzed for differentiation between UCS and PPP. RESULTS: Frontal peak was shifted to the right side of the head in left-sided UCS (mean x-value 207 [192-220]), and right-sided PPP (mean x-value 210 [200-216]), and to the left in right-sided UCS (mean x-value 161 [156-166]), and left-sided PPP (mean x-value 150 [144-154]). Occipital peak was significantly shifted to the right side of the head in left-sided PPP (mean x-value 338 [336-340]) and to the left in right-sided PPP (mean x-value 23 [14-32]). Mean x-value of occipital peak was 9 (354-30) in left- and 2 (350-12) in right-sided UCS. Calculated ratio of gradient of the frontal peak is, in combination with the calculated asymmetry ratio of the frontal peak, a distinctive finding. CONCLUSIONS: UCSQ objectively captures shape of synostotic and positional plagiocephaly using 3D photogrammetry, we therefore developed a suitable method to objectively differentiate UCS from PPP using radiation-free methods.


Assuntos
Craniossinostoses , Plagiocefalia não Sinostótica , Plagiocefalia , Humanos , Lactente , Plagiocefalia não Sinostótica/diagnóstico por imagem , Estudos Retrospectivos , Crânio , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Fotogrametria
4.
J Craniofac Surg ; 34(1): 312-317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35949016

RESUMO

Implementation of the Utrecht Cranial Shape Quantificator (UCSQ) classification method on 3D photogrammetry in patients with different types of craniosynostosis is the aim of the present study. Five children (age <1 year) of every group of the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, right-sided and left-sided anterior plagiocephaly) were randomly included. The program 3-Matic (v13.0) was used to import and analyze the included 3dMD photos. Three external landmarks were placed. Using the landmarks, a base plane was created, as well as a plane 4 cm superior to the base plane. Using UCSQ, we created sinusoid curves of the patients, the resulting curves were analyzed and values were extracted for calculations. Results per patient were run through a diagnostic flowchart in order to determine correctness of the flowchart when using 3D photogrammetry. Each of the patients (n=25) of the different craniosynostosis subgroups is diagnosed correctly based on the different steps in the flowchart. This study proposes and implements a diagnostic approach of craniosynostosis based on 3D photogrammetry. By using a diagnostic flowchart based on specific characteristics for every type of craniosynostosis related to specific skull deformities, diagnosis can be established. All variables are expressed in number and are therefore objective.


Assuntos
Craniossinostoses , Plagiocefalia , Criança , Humanos , Lactente , Craniossinostoses/diagnóstico por imagem , Craniossinostoses/cirurgia , Crânio , Ossos Faciais , Fotogrametria/métodos
5.
Brain ; 146(1): 337-348, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36374264

RESUMO

Higher vascular disease burden increases the likelihood of developing dementia, including Alzheimer's disease. Better understanding the association between vascular risk factors and Alzheimer's disease pathology at the predementia stage is critical for developing effective strategies to delay cognitive decline. In this work, we estimated the impact of six vascular risk factors on the presence and severity of in vivo measured brain amyloid-beta (Aß) plaques in participants from the population-based Rotterdam Study. Vascular risk factors (hypertension, hypercholesterolaemia, diabetes, obesity, physical inactivity and smoking) were assessed 13 (2004-2008) and 7 years (2009-2014) prior to 18F-florbetaben PET (2018-2021) in 635 dementia-free participants. Vascular risk factors were associated with binary amyloid PET status or continuous PET readouts (standard uptake value ratios, SUVrs) using logistic and linear regression models, respectively, adjusted for age, sex, education, APOE4 risk allele count and time between vascular risk and PET assessment. Participants' mean age at time of amyloid PET was 69 years (range: 60-90), 325 (51.2%) were women and 190 (29.9%) carried at least one APOE4 risk allele. The adjusted prevalence estimates of an amyloid-positive PET status markedly increased with age [12.8% (95% CI 11.6; 14) in 60-69 years versus 35% (36; 40.8) in 80-89 years age groups] and APOE4 allele count [9.7% (8.8; 10.6) in non-carriers versus 38.4% (36; 40.8) to 60.4% (54; 66.8) in carriers of one or two risk allele(s)]. Diabetes 7 years prior to PET assessment was associated with a higher risk of a positive amyloid status [odds ratio (95% CI) = 3.68 (1.76; 7.61), P < 0.001] and higher standard uptake value ratios, indicating more severe Aß pathology [standardized beta = 0.40 (0.17; 0.64), P = 0.001]. Hypertension was associated with higher SUVr values in APOE4 carriers (mean SUVr difference of 0.09), but not in non-carriers (mean SUVr difference 0.02; P = 0.005). In contrast, hypercholesterolaemia was related to lower SUVr values in APOE4 carriers (mean SUVr difference -0.06), but not in non-carriers (mean SUVr difference 0.02). Obesity, physical inactivity and smoking were not related to amyloid PET measures. The current findings suggest a contribution of diabetes, hypertension and hypercholesterolaemia to the pathophysiology of Alzheimer's disease in a general population of older non-demented adults. As these conditions respond well to lifestyle modification and drug treatment, further research should focus on the preventative effect of early risk management on the development of Alzheimer's disease neuropathology.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Diabetes Mellitus , Hipercolesterolemia , Hipertensão , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Masculino , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Hipercolesterolemia/patologia , Tomografia por Emissão de Pósitrons , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/patologia , Encéfalo/patologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/patologia , Hipertensão/epidemiologia , Hipertensão/patologia , Obesidade/patologia
6.
Alzheimer Dis Assoc Disord ; 36(4): 327-334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36445223

RESUMO

BACKGROUND: Intracranial stenosis (ICS) and brain amyloid-beta (Aß) have been associated with cognition and dementia. We aimed to investigate the association between ICS and brain Aß and their independent and joint associations with cognition. METHODS: We conducted a cross-sectional study of 185 patients recruited from a memory clinic. ICS was measured on 3-dimensional time-of-flight magnetic resonance angiography and defined as stenosis ≥50%. Brain Aß was measured with [ 11 C] Pittsburgh compound B-positron emission tomography imaging. Cognition was assessed with a locally validated neuropsychological battery. RESULTS: A total of 17 (9.2%) patients had ICS, and the mean standardized uptake value ratio was 1.4 (±0.4 SD). ICS was not significantly associated with brain Aß deposition. ICS was significantly associated with worse global cognition (ß: -1.26, 95% CI: -2.25; -0.28, P =0.013), executive function (ß: -1.04, 95% CI: -1.86; -0.22, P =0.015) and visuospatial function (ß: -1.29, 95% CI: -2.30; -0.27, P =0.015). Moreover, in ICS patients without dementia (n=8), the presence of Aß was associated with worse performance on visuomotor speed. CONCLUSIONS: ICS was significantly associated with worse cognition and showed interaction with brain Aß such that patients with both pathologies performed worse on visuomotor speed specifically in those without dementia. Further studies may clarify if ICS and brain Aß deposition indeed have a synergistic association with cognition.


Assuntos
Cognição , Demência , Humanos , Constrição Patológica , Estudos Transversais , Peptídeos beta-Amiloides , Encéfalo
7.
Antioxidants (Basel) ; 11(9)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36139790

RESUMO

Low blood concentrations of the diet-derived compound ergothioneine (ET) have been associated with cognitive impairment and cerebrovascular disease (CeVD) in cross-sectional studies, but it is unclear whether ET levels can predict subsequent cognitive and functional decline. Here, we examined the temporal relationships between plasma ET status and cognition in a cohort of 470 elderly subjects attending memory clinics in Singapore. All participants underwent baseline plasma ET measurements as well as neuroimaging for CeVD and brain atrophy. Neuropsychological tests of cognition and function were assessed at baseline and follow-up visits for up to five years. Lower plasma ET levels were associated with poorer baseline cognitive performance and faster rates of decline in function as well as in multiple cognitive domains including memory, executive function, attention, visuomotor speed, and language. In subgroup analyses, the longitudinal associations were found only in non-demented individuals. Mediation analyses showed that the effects of ET on cognition seemed to be largely explainable by severity of concomitant CeVD, specifically white matter hyperintensities, and brain atrophy. Our findings support further assessment of plasma ET as a prognostic biomarker for accelerated cognitive and functional decline in pre-dementia and suggest possible therapeutic and preventative measures.

8.
Pediatr Neurol ; 131: 42-48, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35483131

RESUMO

BACKGROUND: Children with trigonocephaly are at risk for neurodevelopmental disorders. The aim of this study is to investigate white matter properties of the frontal lobes in young, unoperated patients with metopic synostosis as compared to healthy controls using diffusion tension imaging (DTI). METHODS: Preoperative DTI data sets of 46 patients with trigonocephaly with a median age of 0.49 (interquartile range: 0.38) years were compared with 21 controls with a median age of 1.44 (0.98) years. White matter metrics of the tracts in the frontal lobe were calculated using FMRIB Software Library (FSL). The mean value of tract-specific fractional anisotropy (FA) and mean diffusivity (MD) were estimated for each subject and compared to healthy controls. By linear regression, FA and MD values per tract were assessed by trigonocephaly, sex, and age. RESULTS: The mean FA and MD values in the frontal lobe tracts of untreated trigonocephaly patients, younger than 3 years, were not significantly different in comparison to controls, where age showed to be a significant associated factor. CONCLUSIONS: Microstructural parameters of white matter tracts of the frontal lobe of patients with trigonocephaly are comparable to those of controls aged 0-3 years.


Assuntos
Craniossinostoses , Substância Branca , Anisotropia , Encéfalo , Criança , Craniossinostoses/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Lobo Frontal/diagnóstico por imagem , Humanos , Lactente , Substância Branca/diagnóstico por imagem
9.
J Alzheimers Dis ; 86(3): 1093-1105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35180121

RESUMO

BACKGROUND: P-wave terminal force in lead V1 (PTFV1) on electrocardiography has been associated with atrial fibrillation and ischemic stroke. OBJECTIVE: To investigate whether PTFV1 is associated with cerebral small vessel disease (CSVD) markers and etiological subtypes of cognitive impairment and dementia. METHODS: Participants were recruited from ongoing memory clinic study between August 2010 to January 2019. All participants underwent physical and medical evaluation along with an electrocardiography and 3 T brain magnetic resonance imaging. Participants were classified as no cognitive impairment, cognitive impairment no dementia, vascular cognitive impairment no dementia, and dementia subtypes (Alzheimer's disease and vascular dementia). Elevated PTFV1 was defined as > 4,000µV×ms and measured manually on ECG. RESULTS: Of 408 participants, 78 (19.1%) had elevated PTFV1 (37 women [47%]; mean [SD] age, 73.8 [7.2] years). The participants with elevated PTFV1 had higher burden of lacunes, cerebral microbleeds (CMB), and cortical microinfarcts. As for the CMB location, persons with strictly deep CMB and mixed CMB had significantly higher PTFV1 than those with no CMB (p = 0.005, p = 0.007). Regardless of adjustment for cardiovascular risk factors and/or heart diseases, elevated PTFV1 was significantly associated with presence of CMB (odds ratio, 2.26; 95% CI,1.33-3.91). CONCLUSION: Elevated PTFV1 was associated with CSVD, especially deep CMB. PTFV1 in vascular dementia was also higher compared to Alzheimer's disease. Thus, PTFV1 might be a potential surrogate marker of brain-heart connection and vascular brain damage.


Assuntos
Doença de Alzheimer , Doenças de Pequenos Vasos Cerebrais , Demência Vascular , Idoso , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Demência Vascular/diagnóstico por imagem , Eletrocardiografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Fatores de Risco
10.
Dev Med Child Neurol ; 64(1): 118-124, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34265076

RESUMO

AIM: To assess the relationship of surface area of the cerebral cortex to intracranial volume (ICV) in syndromic craniosynostosis. METHOD: Records of 140 patients (64 males, 76 females; mean age 8y 6mo [SD 5y 6mo], range 1y 2mo-24y 2mo) with syndromic craniosynostosis were reviewed to include clinical and imaging data. Two hundred and three total magnetic resonance imaging (MRI) scans were evaluated in this study (148 patients with fibroblast growth factor receptor [FGFR], 19 patients with TWIST1, and 36 controls). MRIs were processed via FreeSurfer pipeline to determine total ICV and cortical surface area (CSA). Scaling coefficients were calculated from log-transformed data via mixed regression to account for multiple measurements, sex, syndrome, and age. Educational outcomes were reported by syndrome. RESULTS: Mean ICV was greater in patients with FGFR (1519cm3 , SD 269cm3 , p=0.016) than in patients with TWIST1 (1304cm3 , SD 145cm3 ) or controls (1405cm3 , SD 158cm3 ). CSA was related to ICV by a scaling law with an exponent of 0.68 (95% confidence interval [CI] 0.61-0.76) in patients with FGFR compared to 0.81 (95% CI 0.50-1.12) in patients with TWIST1 and 0.77 (95% CI 0.61-0.93) in controls. Lobar analysis revealed reduced scaling in the parietal (0.50, 95% CI 0.42-0.59) and occipital (0.67, 95% CI 0.54-0.80) lobes of patients with FGFR compared with controls. Modified learning environments were needed more often in patients with FGFR. INTERPRETATION: Despite adequate ICV in FGFR-mediated craniosynostosis, CSA development is reduced, indicating maldevelopment, particularly in parietal and occipital lobes. Modified education is also more common in patients with FGFR.


Assuntos
Córtex Cerebral/anormalidades , Craniossinostoses/complicações , Malformações do Desenvolvimento Cortical/etiologia , Adolescente , Córtex Cerebral/diagnóstico por imagem , Criança , Pré-Escolar , Craniossinostoses/diagnóstico por imagem , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Adulto Jovem
11.
Free Radic Biol Med ; 177: 201-211, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34673145

RESUMO

Ergothioneine (ET) is a dietary amino-thione with strong antioxidant and cytoprotective properties and has possible therapeutic potential for neurodegenerative and vascular diseases. Decreased blood concentrations of ET have been found in patients with mild cognitive impairment, but its status in neurodegenerative and vascular dementias is currently unclear. To address this, a cross-sectional study was conducted on 496 participants, consisting of 88 with no cognitive impairment (NCI), 201 with cognitive impairment, no dementia (CIND) as well as 207 with dementia, of whom 160 have Alzheimer's Disease (AD) and 47 have vascular dementia. All subjects underwent blood-draw, neuropsychological assessments, as well as neuroimaging assessments of cerebrovascular diseases (CeVD) and brain atrophy. Plasma ET as well as its metabolite l-hercynine were measured using high sensitivity liquid chromatography tandem-mass spectrometry (LC-MS/MS). Plasma ET concentrations were lowest in dementia (p < 0.001 vs. NCI and CIND), with intermediate levels in CIND (p < 0.001 vs. NCI). A significant increase in l-hercynine to ET ratio was also observed in dementia (p < 0.01 vs. NCI). In multivariate models adjusted for demographic and vascular risk factors, lower levels of ET were significantly associated with dementia both with or without CeVD, while ET associations with CIND were significant only in the presence of CeVD. Furthermore, lower ET levels were also associated with white matter hyperintensities and brain atrophy markers (reduced global cortical thickness and hippocampal volumes). The incremental decreases in ET levels along the CIND-dementia clinical continuum suggest that low levels of ET are associated with disease severity and could be a potential biomarker for cognitive impairment. Deficiency of ET may contribute towards neurodegeneration- and CeVD-associated cognitive impairments, possibly via the exacerbation of oxidative stress in these conditions.


Assuntos
Doença de Alzheimer , Transtornos Cerebrovasculares , Disfunção Cognitiva , Ergotioneína , Cromatografia Líquida , Disfunção Cognitiva/etiologia , Estudos Transversais , Humanos , Imageamento por Ressonância Magnética , Espectrometria de Massas em Tandem
12.
Curr Alzheimer Res ; 18(5): 399-413, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34420506

RESUMO

BACKGROUND: Cerebral Small Vessel Disease (SVD); lacunes, Cerebral Microbleeds (CMBs), and White Matter Hyperintensities (WMH) have a vital role in cognitive impairment and dementia. SVD in lobar location is related to cerebral amyloid angiopathy, whereas SVD in a deep location with hypertensive arteriopathy. It remains unclear how different locations of SVD affect long-term cognitive decline. The present study aimed to analyse the association between different locations and severity of SVD with global and domain-specific cognitive decline over the follow-up interval of 3 years. METHODS: We studied 428 participants who had performed MRI scans at baseline and at least 3 neuropsychological assessments. Locations of lacunes and CMBs were categorized into strictly lobar, strictly deep and mixed-location, WMH volume into anterior and posterior. The National Institute of Neurological Disorders and Stroke-Canadian Stroke Network Harmonization Neuropsychological Battery was used to assess cognitive function. To analyse the association between baseline location and severity of SVD with cognitive decline, linear regression models with generalized estimated equations were constructed to calculate the mean difference, 95% confidence interval and two-way interaction factor between time and SVD. RESULTS: Increased numbers of baseline CMBs were associated with a decline in global cognition as well as a decline in executive function and memory domains. Location-specific analysis showed similar results with strictly lobar CMBs. There was no association with strictly deep and mixed-location CMBs with cognitive decline. Baseline WMH volume was associated with a decline in global cognition, executive function and memory. Similar results were obtained with anterior and posterior WMH volumes. Lacunes and their locations were not associated with cognitive decline. CONCLUSION: Strictly lobar CMBs, as well as WMH volume in anterior and posterior regions, were associated with cognitive decline. Future research focuses are warranted to evaluate interventions that may prevent cognitive decline related to SVD.


Assuntos
Povo Asiático/estatística & dados numéricos , Doenças de Pequenos Vasos Cerebrais/complicações , Disfunção Cognitiva/etnologia , Substância Branca/patologia , Idoso , Encéfalo/patologia , Canadá , Cognição , Função Executiva , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos/estatística & dados numéricos
13.
J Alzheimers Dis ; 82(2): 561-573, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34057087

RESUMO

BACKGROUND: Cerebrovascular disease (CeVD) is an underlying cause of cognitive impairment and dementia. Hypertension is a known risk factor of CeVD, but the effects of mean of visit-to-visit blood pressure (BP) on incident CeVD and functional-cognitive decline remains unclear. OBJECTIVE: To determine the association between mean of visit-to-visit BP with the incidence and progression of CeVD [white matter hyperintensities (WMH), infarcts (cortical infarcts and lacunes), cerebral microbleeds (CMBs), intracranial stenosis, and hippocampal volume] as well as functional-cognitive decline over 2 years of follow-up. METHODS: 373 patients from a memory-clinic underwent BP measurements at baseline, year 1, and year 2. The mean of visit-to-visit systolic BP, diastolic BP, pulse pressure, and mean arterial pressure were calculated. Baseline and year 2 MRI scans were graded for WMH, infarcts, CMBs, intracranial stenosis, and hippocampal volume. Functional-cognitive decline was assessed using locally validated protocol. Logistic and linear regression models with odds ratios, mean difference, and 95%confidence interval were constructed to analyze associations of visit-to-visit BP on CeVD incidence and progression as well as functional-cognitive decline. RESULTS: Higher mean of visit-to-visit diastolic BP was associated with WMH progression. Higher tertiles of diastolic BP was associated with WMH progression and incident CMBs. There was no association between mean of visit-to-visit BP measures with incident cerebral infarcts, intracranial stenosis, change in hippocampal volume, and functional-cognitive decline. CONCLUSION: These findings suggest the possibility of hypertension-related vascular brain damage. Careful monitoring and management of BP in elderly patients is essential to reduce the incidence and progression of CeVD.


Assuntos
Encéfalo , Transtornos Cerebrovasculares , Disfunção Cognitiva , Hipertensão , Idoso , Assistência Ambulatorial/estatística & dados numéricos , Monitorização Ambulatorial da Pressão Arterial/métodos , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/psicologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/psicologia , Imageamento por Ressonância Magnética/métodos , Masculino , Testes Neuropsicológicos , Medição de Risco , Fatores de Risco , Singapura/epidemiologia
14.
Alzheimers Dement ; 17(10): 1649-1662, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33792168

RESUMO

INTRODUCTION: There is increasing evidence that phosphorylated tau (P-tau181) is a specific biomarker for Alzheimer's disease (AD) pathology, but its potential utility in non-White patient cohorts and patients with concomitant cerebrovascular disease (CeVD) is unknown. METHODS: Single molecule array (Simoa) measurements of plasma P-tau181, total tau, amyloid beta (Aß)40 and Aß42, as well as derived ratios were correlated with neuroimaging modalities indicating brain amyloid (Aß+), hippocampal atrophy, and CeVD in a Singapore-based cohort of non-cognitively impaired (NCI; n = 43), cognitively impaired no dementia (CIND; n = 91), AD (n = 44), and vascular dementia (VaD; n = 22) subjects. RESULTS: P-tau181/Aß42 ratio showed the highest area under the curve (AUC) for Aß+ (AUC = 0.889) and for discriminating between AD Aß+ and VaD Aß- subjects (AUC = 0.903). In addition, P-tau181/Aß42 ratio was associated with hippocampal atrophy. None of the biomarkers was associated with CeVD. DISCUSSION: Plasma P-tau181/Aß42 ratio may be a noninvasive means of identifying AD with elevated brain amyloid in populations with concomitant CeVD.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/sangue , Povo Asiático/estatística & dados numéricos , Transtornos Cerebrovasculares/complicações , Fragmentos de Peptídeos/sangue , Proteínas tau/sangue , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/patologia , Atrofia/patologia , Biomarcadores/sangue , Encéfalo/patologia , Disfunção Cognitiva/patologia , Estudos de Coortes , Hipocampo/patologia , Humanos , Fosforilação , Tomografia por Emissão de Pósitrons , Singapura
15.
J Cereb Blood Flow Metab ; 41(8): 1858-1872, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33530830

RESUMO

To determine whether white matter network disruption mediates the association between MRI markers of cerebrovascular disease (CeVD) and cognitive impairment. Participants (n = 253, aged ≥60 years) from the Epidemiology of Dementia in Singapore study underwent neuropsychological assessments and MRI. CeVD markers were defined as lacunes, white matter hyperintensities (WMH), microbleeds, cortical microinfarcts, cortical infarcts and intracranial stenosis (ICS). White matter microstructure damage was measured as fractional anisotropy and mean diffusivity by tract based spatial statistics from diffusion tensor imaging. Cognitive function was summarized as domain-specific Z-scores.Lacunar counts, WMH volume and ICS were associated with worse performance in executive function, attention, language, verbal and visual memory. These three CeVD markers were also associated with white matter microstructural damage in the projection, commissural, association, and limbic fibers. Path analyses showed that lacunar counts, higher WMH volume and ICS were associated with executive and verbal memory impairment via white matter disruption in commissural fibers whereas impairment in the attention, visual memory and language were mediated through projection fibers.Our study shows that the abnormalities in white matter connectivity may underlie the relationship between CeVD and cognition. Further longitudinal studies are needed to understand the cause-effect relationship between CeVD, white matter damage and cognition.


Assuntos
Transtornos Cerebrovasculares/patologia , Disfunção Cognitiva/diagnóstico , Substância Branca/fisiopatologia , Idoso , Atenção , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/diagnóstico por imagem , Disfunção Cognitiva/complicações , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória , Pessoa de Meia-Idade , Substância Branca/ultraestrutura
16.
Stroke ; 52(3): 922-930, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33535785

RESUMO

BACKGROUND AND PURPOSE: Cortical cerebral microinfarcts (CMIs) have been linked with dementia and impaired cognition in cross-sectional studies. However, the clinical relevance of CMIs in a large population-based setting is lacking. We examine the association of cortical CMIs detected on 1.5T magnetic resonance imaging with cardiovascular risk factors, cerebrovascular disease, and brain tissue volumes. We further explore the association between cortical CMIs with cognitive decline and risk of stroke, dementia, and mortality in the general population. METHODS: Two thousand one hundred fifty-six participants (age: 75.7±5.9 years, women: 55.6%) with clinical history and baseline magnetic resonance imaging (January 2009-December 2013) were included from the Rotterdam Study. Cortical CMIs were graded based on a previously validated method. Markers of cerebrovascular disease and brain tissue volumes were assessed on magnetic resonance imaging. Cognition was assessed using a detailed neuropsychological test at baseline and at 5 years of follow-up. Data on incident stroke, dementia, and mortality were included until January 2016. RESULTS: Two hundred twenty-seven individuals (10.5%) had ≥1 cortical CMIs. The major risk factors of cortical CMIs were male sex, current smoking, history of heart disease, and stroke. Furthermore, presence of cortical CMIs was associated with infarcts and smaller brain volume. Persons with cortical CMIs showed cognitive decline in Stroop tests (color-naming and interference subtasks; ß for color-naming, 0.18 [95% CI, 0.04-0.33], P interaction ≤0.001 and ß for interference subtask, 1.74, [95% CI, 0.66-2.82], P interaction ≤0.001). During a mean follow-up of 5.2 years, 73 (4.3%) individuals developed incident stroke, 95 (5.1%) incident dementia, and 399 (19.2%) died. People with cortical CMIs were at an increased risk of stroke (hazard ratio, 1.18 [95% CI, 1.09-1.28]) and mortality (hazard ratio, 1.09 [95% CI, 1.00-1.19]). CONCLUSIONS: Cortical CMIs are highly prevalent in a population-based setting and are associated with cardiovascular disease, cognitive decline, and increased risk of stroke and mortality. Future investigations will have to show whether cortical CMIs are a useful biomarker to intervene upon to reduce the burden of stroke.


Assuntos
Infarto Encefálico/diagnóstico , Encéfalo/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Demência/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Biomarcadores , Infarto Encefálico/epidemiologia , Cognição , Demência/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Modelos de Riscos Proporcionais , Fatores de Risco
17.
Neuroimage ; 227: 117646, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33338617

RESUMO

Alzheimer's disease (AD) is the most common form of dementia and is phenotypically heterogeneous. APOE is a triallelic gene which correlates with phenotypic heterogeneity in AD. In this work, we determined the effect of APOE alleles on the disease progression timeline of AD using a discriminative event-based model (DEBM). Since DEBM is a data-driven model, stratification into smaller disease subgroups would lead to more inaccurate models as compared to fitting the model on the entire dataset. Hence our secondary aim is to propose and evaluate novel approaches in which we split the different steps of DEBM into group-aspecific and group-specific parts, where the entire dataset is used to train the group-aspecific parts and only the data from a specific group is used to train the group-specific parts of the DEBM. We performed simulation experiments to benchmark the accuracy of the proposed approaches and to select the optimal approach. Subsequently, the chosen approach was applied to the baseline data of 417 cognitively normal, 235 mild cognitively impaired who convert to AD within 3 years, and 342 AD patients from the Alzheimers Disease Neuroimaging Initiative (ADNI) dataset to gain new insights into the effect of APOE carriership on the disease progression timeline of AD. In the ε4 carrier group, the model predicted with high confidence that CSF Amyloidß42 and the cognitive score of Alzheimer's Disease Assessment Scale (ADAS) are early biomarkers. Hippocampus was the earliest volumetric biomarker to become abnormal, closely followed by the CSF Phosphorylated Tau181 (PTAU) biomarker. In the homozygous ε3 carrier group, the model predicted a similar ordering among CSF biomarkers. However, the volume of the fusiform gyrus was identified as one of the earliest volumetric biomarker. While the findings in the ε4 carrier and the homozygous ε3 carrier groups fit the current understanding of progression of AD, the finding in the ε2 carrier group did not. The model predicted, with relatively low confidence, CSF Neurogranin as one of the earliest biomarkers along with cognitive score of Mini-Mental State Examination (MMSE). Amyloid ß42 was found to become abnormal after PTAU. The presented models could aid understanding of the disease, and in selecting homogeneous group of presymptomatic subjects at-risk of developing symptoms for clinical trials.


Assuntos
Algoritmos , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Apolipoproteínas E/genética , Idoso , Doença de Alzheimer/fisiopatologia , Encéfalo/patologia , Encéfalo/fisiopatologia , Progressão da Doença , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Neuroimagem/métodos
18.
Eur J Pediatr ; 180(4): 1211-1217, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33151409

RESUMO

In this study, we diagnose skull shape deformities by analysing sinusoid curves obtained from standardized computed tomography (CT) slices of the skull for the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, right- and left-sided anterior plagiocephaly). Scaphocephaly has a high forehead peak and low troughs, in contrast to brachycephaly. Anterior plagiocephaly has asymmetry and shifting of the forehead peak. Trigonocephaly has a high and narrow frontal peak. Control patients have a symmetrical skull shape with low troughs and a high and broader frontal peak. Firstly, we included 5 children of every group of the common craniosynostoses and additionally 5 controls for extraction and calculation of characteristics. A diagnostic flowchart was developed. Secondly, we included a total of 51 craniosynostosis patients to validate the flowchart. All patients were correctly classified using the flowchart.Conclusion: Our study proposes and implements a new diagnostic approach of craniosynostosis. We describe a diagnostic flowchart based on specific characteristics for every type of craniosynostosis related to the specific skull deformities and control patients. All variables are expressed in number; therefore, we are able to use these variables in future research to quantify the different types of craniosynostosis. What is Known: • Premature fusion of one or more cranial sutures results in a specific cranial shape. • Clinical diagnosis is relatively simple; however, objective diagnosis based on distinctive values is difficult. What is New: • Using external landmarks and curve analysis, distinctive variables, and values for every type of craniosynostosis related to the specific skull deformities were determined and used to create a diagnostic flowchart for diagnosis. • Validation with an independent data set of 51 patients showed that all patients were correctly classified.


Assuntos
Craniossinostoses , Criança , Craniossinostoses/diagnóstico por imagem , Humanos , Lactente , Crânio/diagnóstico por imagem , Tomografia Computadorizada por Raios X
19.
Am J Geriatr Psychiatry ; 29(2): 156-165, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32651052

RESUMO

OBJECTIVE: The impact of white matter hyperintensities (WMH) on language possibly depends on lesion location through disturbance of strategic white matter tracts. We examined the impact of WMH location on language in elderly Asians. DESIGN: Cross-sectional. SETTING: Population-based. PARTICIPANTS: Eight-hundred nineteen residents of Singapore, ages (≥65 years). MEASUREMENTS: Clinical, cognitive and 3T magnetic resonance imaging assessments were performed on all participants. Language was assessed using the Modified Boston Naming Test (MBNT) and Verbal Fluency (VF). Hypothesis-free region-of-interest-based (ROI) analyses based on major white matter tracts were used to determine the association between WMH location and language. Conditional dependencies between the regional WMH volumes and language were examined using Bayesian-network analysis. RESULTS: ROI-based analyses showed that WMH located within the anterior thalamic radiation (mean difference: -0.12, 95% confidence interval [CI]: -0.22; -0.02, p = 0.019) and uncinate fasciculus (mean difference: -0.09, 95% CI: -0.18; -0.01, p = 0.022) in the left hemisphere were significantly associated with worse VF but did not survive multiple testing. Conversely, WMH volume in the left cingulum of cingulate gyrus was significantly associated with MBNT performance (mean difference: -0.09, 95% CI: -0.17; -0.02, p = 0.016). Bayesian-network analyses confirmed the left cingulum of cingulate gyrus as a direct determinant of MBNT performance. CONCLUSION: Our findings identify the left cingulum of cingulate gyrus as a strategic white matter tract for MBNT, suggesting that language - is sensitive to subcortical ischemic damage. Future studies on the role of sporadic ischemic lesions and vascular cognitive impairment should not only focus on total WMH volume but should also take WMH lesion location into account when addressing language.


Assuntos
Idioma , Substância Branca/patologia , Idoso , Teorema de Bayes , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Singapura
20.
Cleft Palate Craniofac J ; 58(7): 832-837, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33078622

RESUMO

OBJECTIVES: Severity of unilateral coronal synostosis (UCS) can vary. Quantification is important for treatment, expectations of treatment and natural outcome, and education of the patient and parents. DESIGN: Retrospective study. SETTING: Primary craniofacial center. PATIENTS, PARTICIPANTS: Twenty-three preoperative patients with unilateral coronal craniosynostosis (age < 2 years). INTERVENTION: Utrecht Cranial Shape Quantifier (UCSQ) was used to quantify severity using the variables: asymmetry ratio of frontal peak and ratio of frontal peak gradient. MAIN OUTCOME MEASURES(S): The UCSQ variables were combined and related to visual score using Pearson correlation coefficient; UCSQ and visual score were additionally compared to Di Rocco classification by one-way analysis of variance or Kruskal-Wallis test. All measurements were made on computed tomography scans. RESULTS: Good correlation between UCSQ and visual score was found (r = 0.67). No statistically significant differences were found between group means of UCSQ in the 3 categories of Di Rocco classification (F2,20 = 0.047; P > .05). Kruskal-Wallis test showed no significant differences between group means of visual score in the 3 categories of Di Rocco classification (Kruskal-Wallis H (2) = 0.871; P > .05). CONCLUSIONS: Using UCSQ, we can quantify UCS according to severity using characteristics, it outperforms traditional methods and captures the whole skull shape. In future research, we can apply UCSQ to 3D-photogrammetry due to the utilization of external landmarks.


Assuntos
Craniossinostoses , Sinostose , Pré-Escolar , Suturas Cranianas , Craniossinostoses/diagnóstico por imagem , Humanos , Lactente , Fotogrametria , Estudos Retrospectivos , Crânio , Tomografia Computadorizada por Raios X
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