Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 39
Filter
1.
J Prev Alzheimers Dis ; 11(3): 549-557, 2024.
Article in English | MEDLINE | ID: mdl-38706271

ABSTRACT

BACKGROUND: In an exploratory 91-participant phase 2a clinical trial (AscenD-LB, NCT04001517) in dementia with Lewy bodies (DLB), neflamapimod showed improvement over placebo on multiple clinical endpoints. To confirm those results, a phase 2b clinical study (RewinD-LB, NCT05869669 ) that is similar to AscenD-LB has been initiated. OBJECTIVES: To optimize the choice of patient population, primary endpoint, and biomarker evaluations in RewinD-LB. DESIGN: Evaluation of the efficacy results from AscenD-LB, the main results of which, and a re-analysis after stratification for absence or presence of AD co-pathology (assessed by plasma ptau181), have been published. In addition, the MRI data from a prior phase 2a clinical trial in Early Alzheimer's disease (AD), were reviewed. SETTING: 22 clinical sites in the US and 2 in the Netherlands. PARTICIPANTS: Probable DLB by consensus criteria and abnormal dopamine uptake by DaTscan™ (Ioflupane I123 SPECT). INTERVENTION: Neflamapimod 40mg capsules or matching placebo capsules, twice-a-day (BID) or three-times-a-day (TID), for 16 weeks. MEASUREMENTS: 6-test Neuropsychological Test Battery (NTB) assessing attention and executive function, Clinical Dementia Rating Sum-of-Boxes (CDR-SB), Timed Up and Go (TUG), International Shopping List Test (ISLT). RESULTS: Within AscenD-LB, patients without evidence of AD co-pathology exhibited a neflamapimod treatment effect that was greater than that in the overall population and substantial (cohen's d effect size vs. placebo ≥ for CDR-SB, TUG, Attention and ISLT-recognition). In addition, the CDR-SB and TUG performed better than the cognitive tests to demonstrate neflamapimod treatment effect in comparison to placebo. Further, clinical trial simulations indicate with 160-patients (randomized 1:1), RewinD-LB conducted in patients without AD co-pathology has >95% (approaching 100%) statistical power to detect significant improvement over placebo on the CDR-SB. Preliminary evidence of positive treatment effects on beta functional connectivity by EEG and basal forebrain atrophy by MRI were obtained in AscenD-LB and the Early AD study, respectively. CONCLUSION: In addition to use of a single dose regimen of neflamapimod (40mg TID), key distinctions between phase 2b and phase 2a include RewinD-LB (1) excluding patients with AD co-pathology, (2) having CDR-SB as the primary endpoint, and (3) having MRI studies to evaluate effects on basal forebrain atrophy.


Subject(s)
Benzylamines , Fluorocarbons , Indoles , Lewy Body Disease , Humans , Lewy Body Disease/drug therapy , Lewy Body Disease/diagnostic imaging , Aged , Female , Male , Double-Blind Method , Magnetic Resonance Imaging , Biomarkers/blood , Aged, 80 and over , Neuropsychological Tests
2.
J Prev Alzheimers Dis ; 11(1): 65-70, 2024.
Article in English | MEDLINE | ID: mdl-38230718

ABSTRACT

BACKGROUND: KHK6640 is a novel humanized anti-amyloid beta oligomer-specific antibody. Both KHK6640 and the mouse parent antibody E64 have demonstrated high potency and efficacy for cognitive improvement in several rodent Alzheimer's disease models, including an anti-amyloid beta injection mouse model and in age-matched double transgenic littermates. The favorable safety and pharmacokinetic profiles of KHK6640 reported in preclinical studies warrant clinical trials in Alzheimer's disease patients. OBJECTIVES: We evaluated the safety, pharmacokinetics, and efficacy of intravenous and subcutaneous oligomer-specific antibody KHK6640 in treating patients with prodromal Alzheimer's disease or mild to moderate Alzheimer's disease. DESIGN: Phase I/2a, multicenter, randomized, double-blind, placebo-controlled trial. SETTING: Nine sites in Europe participated in this clinical trial. PARTICIPANTS: 97 patients with prodromal Alzheimer's disease or mild to moderate Alzheimer's disease. INTERVENTION: Single and multiple ascending intravenous and subcutaneous doses of KHK6640 in doses ranging from 0.1 mg/kg to 20 mg/kg or placebo was administered to patients monthly for six months. MEASUREMENTS: Primary outcomes were safety including amyloid-related imaging abnormalities for edema and hemorrhage, assessed with magnetic resonance imaging. Plasma and cerebrospinal fluid samples were analyzed to investigate pharmacokinetics and KHK6640 effects on biomarkers. Cognition, brain glucose metabolism and amyloid load were exploratory outcomes. RESULTS: No amyloid-related imaging abnormalities for edema were observed. Amyloid-related imaging abnormalities for hemorrhage were comparable to that of placebo and population background. KHK6640 exposure was approximately dose-equivalent, with a serum terminal elimination half-life of approximately 19 days. KHK6640 pharmacokinetics in serum and cerebrospinal fluid, including cerebrospinal fluid oligomers trapped by the antibody were dose related. Positive trends seen in the positron emission tomography brain glucose metabolism and amyloid load, cerebrospinal tau but cognition assessments were inconclusive, due to low numbers. CONCLUSIONS: KHK6640 was well-tolerated across all doses, without any amyloid-related imaging abnormalities for edema, and amyloid-related imaging abnormalities for hemorrhage was as population background. The demonstrated dose-response of specific target biomarkers provides dosing guidance on dose and administration method selection for further clinical development.


Subject(s)
Alzheimer Disease , Animals , Humans , Mice , Antibodies, Monoclonal, Humanized , Biomarkers , Edema/drug therapy , Glucose/therapeutic use , Hemorrhage/drug therapy
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 7292-7295, 2021 11.
Article in English | MEDLINE | ID: mdl-34892782

ABSTRACT

Cricketers are dynamic players in the field and hence more vulnerable to injuries. The injury rate of Sri Lankan cricketers is very high, resulting in their careers being shortened. Therefore, we established a workload management system for cricketers to resolve this issue with wearable Inertial Measurement Unit (IMU) sensors mounted on their bodies. In order to mitigate their accidents, we evaluated kinds of the activities performed by an athlete using Convolutional Neural Network (CNN) and computed the workload parameters after the session. The expected results of our project were to develop a system to collect and analyze the critical workload parameters of cricketers and showcase results in a user-friendly manner.


Subject(s)
Athletic Injuries , Workload , Athletes , Humans
4.
Alzheimers Res Ther ; 13(1): 142, 2021 08 23.
Article in English | MEDLINE | ID: mdl-34425883

ABSTRACT

BACKGROUND: Varoglutamstat (formerly PQ912) is a small molecule that inhibits the activity of the glutaminyl cyclase to reduce the level of pyroglutamate-A-beta (pGluAB42). Recent studies confirm that pGluAB42 is a particular amyloid form that is highly synaptotoxic and plays a significant role in the development of AD. METHODS: This paper describes the design and methodology behind the phase 2b VIVIAD-trial in AD. The aim of this study is to evaluate varoglutamstat in a state-of-the-art designed, placebo-controlled, double-blind, randomized clinical trial for safety and tolerability, efficacy on cognition, and effects on brain activity and AD biomarkers. In addition to its main purpose, the trial will explore potential associations between novel and established biomarkers and their individual and composite relation to disease characteristics. RESULTS: To be expected early 2023 CONCLUSION: This state of the art phase 2b study will yield important results for the field with respect to trial methodology and for the treatment of AD with a small molecule directed against pyroglutamate-A-beta. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04498650.


Subject(s)
Alzheimer Disease , Aminoacyltransferases , Double-Blind Method , Humans , Treatment Outcome
5.
Tijdschr Psychiatr ; 63(5): 366-373, 2021.
Article in Dutch | MEDLINE | ID: mdl-34043226

ABSTRACT

BACKGROUND: The behavioural variant of frontotemporal dementia (bvFTD) strongly resembles primary psychiatric disorders. Furthermore, a bvFTD mimic may occur, without neurodegenerative aetiology. AIM: To offer psychiatrist clinical tools for making or ruling out a bvFTD diagnosis. METHOD: To present the results of the first prospective cohort study on bvFTD patients and primary psychiatric patients. Results are discussed within the context of the international literature. RESULTS: Frontotemporal atrophy on imaging confirms a suspected bvFTD diagnosis. Merely fulfilling the bvFTD clinical criteria, with or without frontotemporal hypometabolism on functional imaging, may also result from primary psychiatric disorders or the bvFTD-phenocopy syndrome. A high level of stereotypy, hyperorality, a low level of depressive symptoms, impaired social cognition or absent insight increases the probability of bvFTD. Biomarker or genetic tests and follow-up are recommended. CONCLUSIONS A bvFTD diagnosis should be made multidisciplinary. Without the confirmation of atrophy or genetics, great reserve in making the diagnosis is in place and careful analyses for psychiatric aetiologies is advised.


Subject(s)
Frontotemporal Dementia , Psychiatry , Diagnosis, Differential , Frontotemporal Dementia/diagnosis , Humans , Neuroimaging , Neuropsychological Tests , Prospective Studies
6.
Eur J Nucl Med Mol Imaging ; 48(3): 747-756, 2021 03.
Article in English | MEDLINE | ID: mdl-32888039

ABSTRACT

PURPOSE: To determine thresholds for amyloid beta pathology and evaluate associations with longitudinal memory performance with the aim to identify a grey zone of early amyloid beta accumulation and investigate its clinical relevance. METHODS: We included 162 cognitively normal participants with subjective cognitive decline from the SCIENCe cohort (64 ± 8 years, 38% F, MMSE 29 ± 1). Each underwent a dynamic [18F] florbetapir PET scan, a T1-weighted MRI scan and longitudinal memory assessments (RAVLT delayed recall, n = 655 examinations). PET scans were visually assessed as amyloid positive/negative. Additionally, we calculated the mean binding potential (BPND) and standardized uptake value ratio (SUVr50-70) for an a priori defined composite region of interest. We determined six amyloid positivity thresholds using various data-driven methods (resulting thresholds: BPND 0.19/0.23/0.29; SUVr 1.28/1.34/1.43). We used Cohen's kappa to analyse concordance between thresholds and visual assessment. Next, we used quantiles to divide the sample into two to five subgroups of equal numbers (median, tertiles, quartiles, quintiles), and operationalized a grey zone as the range between the thresholds (0.19-0.29 BPND/1.28-1.43 SUVr). We used linear mixed models to determine associations between thresholds and memory slope. RESULTS: As determined by visual assessment, 24% of 162 individuals were amyloid positive. Concordance with visual assessment was comparable but slightly higher for BPND thresholds (range kappa 0.65-0.70 versus 0.60-0.63). All thresholds predicted memory decline (range beta - 0.29 to - 0.21, all p < 0.05). Analyses in subgroups showed memory slopes gradually became steeper with higher amyloid load (all p for trend < 0.05). Participants with a low amyloid burden benefited from a practice effect (i.e. increase in memory), whilst high amyloid burden was associated with memory decline. Memory slopes of individuals in the grey zone were intermediate. CONCLUSION: We provide evidence that not only high but also grey zone amyloid burden subtly impacts memory function. Therefore, in case a binary classification is required, we suggest using a relatively low threshold which includes grey zone amyloid pathology.


Subject(s)
Alzheimer Disease , Amyloid , Cognitive Dysfunction , Aged , Amyloid beta-Peptides , Aniline Compounds , Female , Humans , Male , Middle Aged , Positron-Emission Tomography
7.
J Prev Alzheimers Dis ; 7(3): 184-194, 2020.
Article in English | MEDLINE | ID: mdl-32463072

ABSTRACT

BACKGROUND: Online programs targeting lifestyle have the potential to benefit brain health. We aimed to develop such a program for individuals with subjective cognitive decline (SCD). These individuals were reported to be at increased risk for dementia, and report both an intrinsic need for brain health information and motivation to participate in prevention strategies. Co-creation and user-evaluation benefits the adherence to and acceptance of online programs. Previously, we developed a prototype of the online program in co-creation with the users . OBJECTIVES: We now aimed to evaluate the user-experiences of our online lifestyle program for brain health. DESIGN: 30-day user test; multi-method. SETTING: Participants were recruited in a memory clinic and (online) research registries in the Netherlands (Alzheimer Center Amsterdam) and Germany (Center for memory disorders, Cologne). PARTICIPANTS: Individuals with SCD (N=137, 65±9y, 57% female). MEASUREMENTS: We assessed user-experiences quantitatively with rating daily advices and usefulness, satisfaction and ease of use questionnaires as well as qualitatively using telephone interviews. RESULTS: Quantitative data showed that daily advices were rated moderately useful (3.5 ±1.5, range 1-5 points). Participants (n=101, 78%) gave moderate ratings on the programs' usability (3.7±1.3, max 7), ease of learning (3.6±1.9) and satisfaction (4.0±1.5), and marginal ratings on the overall usability (63.7±19.0, max 100). Qualitative data collected during telephone interviews showed that participants highly appreciated the content of the program. They elaborated that lower ratings of the program were mainly due to technical issues that hindered a smooth walk through. Participants reported that the program increased awareness of lifestyle factors related to brain health. CONCLUSIONS: Overall user-experience of the online lifestyle program was moderate to positive. Qualitative data showed that content was appreciated and that flawless, easy access technique is essential. The heterogeneity in ratings of program content and in program use highlights the need for personalization. These findings support the use of online self-applied lifestyle programs when aiming to reach large groups of motivated at-risk individuals for brain health promotion.


Subject(s)
Cognitive Dysfunction/psychology , Education, Distance/organization & administration , Health Promotion/methods , Life Style , Female , Focus Groups , Germany , Humans , Male , Middle Aged , Netherlands , Qualitative Research , Registries , Risk Factors , Surveys and Questionnaires
8.
Alzheimers Res Ther ; 11(1): 112, 2019 12 27.
Article in English | MEDLINE | ID: mdl-31882022

ABSTRACT

BACKGROUND: Growing evidence suggests a role of occupation in the emergence and manifestation of dementia. Occupations are often defined by complexity level, although working environments and activities differ in several other important ways. We aimed to capture the multi-faceted nature of occupation through its measurement as a qualitative (instead of a quantitative) variable and explored its relationship with different types of dementia. METHODS: We collected occupational information of 2121 dementia patients with various suspected etiologies from the Amsterdam Dementia Cohort (age 67 ± 8, 57% male; MMSE 21 ± 5). Our final sample included individuals with Alzheimer's disease (AD) dementia (n = 1467), frontotemporal dementia (n = 281), vascular dementia (n = 98), Lewy body disease (n = 174), and progressive supranuclear palsy/corticobasal degeneration (n = 101). Within the AD group, we used neuropsychological data to further characterize patients by clinical phenotypes. All participants were categorized into 1 of 11 occupational classes, across which we evaluated the distribution of dementia (sub)types with χ2 analyses. We gained further insight into occupation-dementia relationships through post hoc logistic regressions that included various demographic and health characteristics as explanatory variables. RESULTS: There were significant differences in the distribution of dementia types across occupation groups (χ2 = 85.87, p < .001). Vascular dementia was relatively common in the Transportation/Logistics sector, and higher vascular risk factors partly explained this relationship. AD occurred less in Transportation/Logistics and more in Health Care/Welfare occupations, which related to a higher/lower percentage of males. We found no relationships between occupational classes and clinical phenotypes of AD (χ2 = 53.65, n.s.). CONCLUSIONS: Relationships between occupation and dementia seem to exist beyond the complexity level, which offers new opportunities for disease prevention and improvement of occupational health policy.


Subject(s)
Dementia, Vascular/diagnosis , Occupations , Aged , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Risk Factors , Sex Factors
9.
Clin Neurophysiol ; 126(3): 497-504, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24969377

ABSTRACT

OBJECTIVE: White matter hyperintensities (WMH), a feature seen on magnetic resonance imaging (MRI) and regarded to reflect small vessel disease, can lead to vascular dementia (WMH-VaD). In WMH-VaD, cognitive deficits typically consist of executive function disturbances, and reduced information processing speed, regarded as a result of cerebral hypoperfusion. We aimed to investigate whether this patient group has typical functional differences from controls. METHODS: Resting-state encephalography studies of 17 VaD patients and 17 age- and gender matched non-demented controls were analysed in the delta, theta, alpha1 and 2, and beta frequency bands. Undirected functional connectivity between electrodes was established with the Phase Lag Index (PLI) and directed functional connectivity with the directed Phase Lag Index (dPLI). PLI and dPLI were related to performance in cognitive testing. RESULTS: Mean PLI did not differ between patients and controls. In the control group dPLI showed anterior to posterior phase gradients in all bands except the delta band. In the VaD patient group this pattern was significantly different without a clear directional pattern. No relationship with cognition was demonstrated. CONCLUSIONS: This study shows a clear front-to-back direction of connectivity in non-demented controls. In VaD patients with extensive WMH, this pattern is disturbed. SIGNIFICANCE: Structural damage at the regions of long distance white matter tracts may induce changes in the direction of phase relationships of distinct brain regions.


Subject(s)
Brain/physiopathology , Dementia, Vascular/physiopathology , Nerve Net/physiopathology , White Matter/physiopathology , Aged , Aged, 80 and over , Brain/pathology , Cognition , Dementia, Vascular/pathology , Electroencephalography , Female , Humans , Magnetic Resonance Imaging/methods , Male , Nerve Net/pathology , Neural Pathways/pathology , Neural Pathways/physiopathology , White Matter/pathology
10.
Psychol Med ; 45(5): 1051-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25229325

ABSTRACT

BACKGROUND: To investigate trajectories of cognitive decline in patients with different types of dementia compared to controls in a longitudinal study. METHOD: In 199 patients with Alzheimer's disease (AD), 10 with vascular dementia (VaD), 26 with dementia with Lewy bodies (DLB), 20 with behavioural variant frontotemporal dementia (bvFTD), 15 with language variant frontotemporal dementia (lvFTD) and 112 controls we assessed five cognitive domains: memory, language, attention, executive and visuospatial functioning, and global cognition (Mini-Mental State Examination, MMSE). All subjects had at least two neuropsychological assessments (median 2, range 2-7). Neuropsychological data were standardized into z scores using baseline performance of controls as reference. Linear mixed models (LMMs) were used to estimate baseline cognitive functioning and cognitive decline over time for each group, adjusted for age, gender and education. RESULTS: At baseline, patients with dementia performed worse than controls in all cognitive domains (p < 0.05) except visuospatial functioning, which was only impaired in patients with AD and DLB (p < 0.001). During follow-up, patients with AD declined in all cognitive domains (p < 0.001). DLB showed decline in every cognitive domain except language and global cognition. bvFTD showed rapid decline in memory, language, attention and executive functioning (all p < 0.01) whereas visuospatial functioning remained fairly stable. lvFTD declined mostly in attention and executive functioning (p < 0.01). VaD showed decline in attention and executive functioning. CONCLUSIONS: We show cognitive trajectories of different types of dementia. These estimations of natural disease course have important value for the design of clinical trials as neuropsychological measures are increasingly being used as outcome measures.


Subject(s)
Alzheimer Disease/psychology , Cognition Disorders/psychology , Dementia, Vascular/psychology , Frontotemporal Dementia/psychology , Lewy Body Disease/psychology , Aged , Alzheimer Disease/physiopathology , Case-Control Studies , Cognition Disorders/physiopathology , Dementia, Vascular/physiopathology , Disease Progression , Executive Function , Female , Frontotemporal Dementia/physiopathology , Humans , Language , Lewy Body Disease/physiopathology , Longitudinal Studies , Male , Memory , Middle Aged , Neuropsychological Tests , Prospective Studies
11.
J Prev Alzheimers Dis ; 1(1): 40-45, 2014.
Article in English | MEDLINE | ID: mdl-29261219

ABSTRACT

During the decade from 2002 to 2012, 99.6% of the 244 agents tested for efficacy in slowing the progression of Alzheimer's' disease (AD) failed to achieve their primary endpoints. At a CTAD symposium on November 14, 2013, in San Diego, USA, an international group of AD researchers met to discuss the evolution of trials over the past 10 years and proposed a number of changes intended to streamline and enhance the efficiency of clinical trials. Approximately 1,031 AD trials were conducted between 2000 and 2012. The number of patients per trial site tended to decrease over time necessitating a larger number of sites. The use of biomarkers for enrichment purposes, or as measures of target engagement or surrogate outcomes, results in higher screen failure and drop-out rates, adding to trial duration and/or costs. Present disease modifying AD trials ask for increasing logistical and technical requirements, necessitating the creation of highly specialized trial facilities and limiting the participation of smaller sites. Due to heavy administrative and regulatory task, only about 13% of the team's time is used for the essential recruitment. Proposals and perspectives: Strategies suggested to improve the efficiency of recruitment include establishing "ready to go cohorts" in advance of trials using biomarkers and clinical measures. Simplification and harmonization of administrative procedures, including harmonization of certification procedures, are urgently needed. Alternative approaches, such as using the Internet to screen volunteers for possible inclusion needs to be evaluated. The AD drug development enterprise from discovery through clinical trials requires re-examination and re-organization if new drugs are to be delivered to patients in a timely way.

12.
J Neurol Neurosurg Psychiatry ; 82(4): 399-404, 2011 Apr.
Article in English | MEDLINE | ID: mdl-20935327

ABSTRACT

BACKGROUND: The two main approaches in aphasia treatment are cognitive-linguistic treatment (CLT), aimed at restoring the linguistic levels affected, semantics, phonology or syntax, and communicative treatment, aimed at optimising information transfer by training compensatory strategies and use of residual language skills. The hypothesis that CLT is more effective than communicative treatment in the early stages after stroke was tested in this study. METHODS: In this multicentre, randomised, parallel group trial with blinded outcome assessment, 80 patients with aphasia after stroke were included within 3 weeks post-stroke. Patients received 6 months of CLT, comprising semantic and/or phonological training, or communicative treatment for at least 2 h per week. They were assessed before treatment and at 3 and 6 months with the Amsterdam-Nijmegen Everyday Language Test (ANELT-A, primary outcome) and semantic and phonological tests (secondary outcomes). The intervention effect was evaluated by means of analysis of covariance, with adjustment for baseline scores. RESULTS: There was no difference between the mean ANELT-A score of the CLT group (n=38) and the communicative treatment group (n=42), at 3 months (adjusted difference 1.5, 95% CI -2.6 to 5.6) or at 6 months (adjusted difference 1.6, 95% CI -2.3 to 5.6) post-stroke. On two of six specific semantic and phonological tests, the mean scores differed significantly, both in favour of CLT. CONCLUSION: This study does not confirm the hypothesis that patients with aphasia after stroke benefit more from CLT, aimed at activation of the underlying semantic and phonologic processes, than from general, non-specific communicative treatment (ISRCTN67723958 Current Controlled Trials).


Subject(s)
Aphasia/therapy , Cognitive Behavioral Therapy/methods , Language Therapy/methods , Stroke/therapy , Aged , Aphasia/complications , Female , Humans , Male , Stroke/complications , Time Factors
13.
Neurology ; 66(4): 540-4, 2006 Feb 28.
Article in English | MEDLINE | ID: mdl-16505309

ABSTRACT

BACKGROUND: Previous 1H-MR spectroscopy (MRS) studies compared biochemical spectra of persons with dementia with those of healthy control subjects. Given the long prodromal period of Alzheimer disease (AD), the authors sought to investigate whether biochemical changes can be observed also in the preclinical period. METHODS: The authors prospectively followed 509 elderly persons (ages 60 to 90), who were free of clinical dementia at baseline, for on average 5.9 years. At baseline, 1H-MRS of the brain (1.5 T) was performed in a plane above the lateral ventricles that comprised mainly white matter voxels. Standard ratios of N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) were calculated. Structural MRI was administered to assess white matter lesions and hippocampal atrophy. All persons were followed for incident dementia through repeated neuropsychological testing and linkage with medical records. RESULTS: During follow-up, 37 persons developed dementia, of whom 27 fulfilled criteria for AD. Overall, biochemical ratios on 1H-MRS at baseline were not associated with the risk of incident dementia. However, people with higher Cho/Cr ratios had a higher risk to develop dementia or AD within 4 years (hazard ratio for dementia per SD increase 1.55 [95% CI 1.05 to 2.28]). This association attenuated and became nonsignificant after adjustment for white matter lesions on MRI. CONCLUSION: These data suggest that there are biochemical changes on 1H-MR spectroscopy of brains of persons with presymptomatic dementia.


Subject(s)
Brain/anatomy & histology , Brain/pathology , Dementia/diagnosis , Magnetic Resonance Spectroscopy/methods , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Time Factors
14.
Circulation ; 112(6): 900-5, 2005 Aug 09.
Article in English | MEDLINE | ID: mdl-16061741

ABSTRACT

BACKGROUND: Inflammatory processes are involved in the development and consequences of atherosclerosis. Whether these processes are also involved in cerebral small-vessel disease is unknown. Cerebral white matter lesions and lacunar brain infarcts are caused by small-vessel disease and are commonly observed on MRI scans in elderly people. These lesions are associated with an increased risk of stroke and dementia. We assessed whether higher C-reactive protein (CRP) levels were related to white matter lesion and lacunar infarcts. METHODS AND RESULTS: We based our study on 1033 participants of the population-based Rotterdam Scan Study for whom complete data on CRP levels were available and who underwent brain MRI scanning. Subjects were 60 to 90 years of age and free of dementia at baseline. Six hundred thirty-six subjects had a second MRI scan on average 3.3 years later. We used multivariate regression models to assess the associations between CRP levels and markers of small-vessel disease. Higher CRP levels were associated with presence and progression of white matter lesions, particularly with marked lesion progression (ORs for highest versus lowest quartile of CRP 3.1 [95% CI 1.3 to 7.2] and 2.5 [95% CI 1.1 to 5.6] for periventricular and subcortical white matter lesion progression, respectively). These associations persisted after adjustment for cardiovascular risk factors and carotid atherosclerosis. Persons with higher CRP levels tended to have more prevalent and incident lacunar infarcts. CONCLUSIONS: Inflammatory processes may be involved in the pathogenesis of cerebral small-vessel disease, in particular, the development of white matter lesions.


Subject(s)
C-Reactive Protein/metabolism , Cerebrovascular Disorders/epidemiology , Microcirculation/physiopathology , Aged , Aged, 80 and over , Biomarkers/blood , Cerebrovascular Disorders/blood , Cohort Studies , Diabetes Mellitus/epidemiology , Female , Follow-Up Studies , Humans , Hypertension/epidemiology , Inflammation/blood , Inflammation/epidemiology , Male , Middle Aged , Netherlands/epidemiology , Risk Factors
15.
Neurogastroenterol Motil ; 17(3): 366-75, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15916624

ABSTRACT

5-Hydroxytryptamine 4 (5-HT4) receptor agonists promote colonic propulsion. The alteration of circular muscle (CM) motility underlying this involves inhibition of contractility via smooth muscle 5-HT4 receptors and proximal colonic motility stimulation, the mechanism of the latter not having been characterized. Our aim was to identify and characterize a 5-HT4 receptor-mediated stimulation of human colon CM contractile activity. 5-HT4 receptor ligands were tested on electrical field stimulation (EFS)-induced contractions of human colonic muscle strips cut in the circular direction (called 'whole tissue' strips). Additionally, after incubation of tissues with [3H]-choline these compounds were tested on EFS-induced release of tritium in whole tissue strips and in 'isolated' CM strips, obtained by superficial cutting in the CM layer. Tetrodotoxin and atropine blocked EFS-induced contractions of whole tissue CM strips. Prucalopride (0.3 micromol L-1) evoked a heterogenous response on EFS-induced contraction, ranging from inhibition (most frequently observed) to enhancement. In the release experiments, EFS-induced tritium efflux was blocked by tetrodotoxin. Prucalopride increased EFS-induced tritium and [3H]-acetylcholine efflux in whole tissue and in isolated CM strips. All effects of prucalopride were antagonized by the selective 5-HT4 receptor antagonist GR113808. The results obtained indicate the presence of excitatory 5-HT4 receptors on cholinergic nerves within the CM of human colon.


Subject(s)
Colon/innervation , Colon/physiology , Muscle, Smooth/innervation , Muscle, Smooth/physiology , Parasympathetic Nervous System/physiology , Receptors, Serotonin, 5-HT4/drug effects , Acetylcholine/metabolism , Benzofurans/pharmacology , Chromatography, High Pressure Liquid , Colon/metabolism , Electric Stimulation , Enzyme Inhibitors/pharmacology , Humans , In Vitro Techniques , Muscle Contraction/drug effects , Muscle Contraction/physiology , Muscle, Smooth/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitroarginine/pharmacology , Serotonin Antagonists/pharmacology , Serotonin Receptor Agonists/pharmacology , Tetrodotoxin/pharmacology
16.
Neurology ; 64(2): 263-7, 2005 Jan 25.
Article in English | MEDLINE | ID: mdl-15668423

ABSTRACT

BACKGROUND: Blood pressure level is associated with the risk of clinical Alzheimer disease (AD), yet the underlying mechanisms are unclear. High blood pressure levels may cause cerebral small-vessel pathology, which contributes to cognitive decline in patients with AD. Alternatively, in persons with high blood pressure, increased numbers of neurofibrillary tangles and amyloid plaques at autopsy have also been observed, suggesting direct links between blood pressure and AD. OBJECTIVE: To investigate the association of blood pressure and markers of small-vessel disease (white matter lesions [WMLs] on MRI) with hippocampal and amygdalar atrophy on MRI-potential in vivo indicators of Alzheimer pathology. METHODS: In 1995 to 1996, 511 nondemented elderly subjects (age 60 to 90) underwent MRI. The extent of WMLs was assessed, and volumes of the hippocampus and amygdala were measured. Blood pressure levels were assessed at the time of MRI and 5 years before the MRI. RESULTS: Higher diastolic blood pressure 5 years before MRI predicted more hippocampal atrophy in persons untreated for hypertension (per SD increase -0.10 mL [95% CI -0.19 to -0.02, p = 0.02]). Conversely, in persons treated for hypertension, a low diastolic blood pressure was associated with more severe atrophy. Persons with more WMLs on MRI more often had severe atrophy of the hippocampus and amygdala. CONCLUSION: Blood pressure and indicators of small-vessel disease in the brain may be associated with atrophy of structures affected by Alzheimer pathology.


Subject(s)
Blood Pressure , Hypertension/epidemiology , Myelin Sheath/pathology , Temporal Lobe/pathology , Adult , Aged , Aged, 80 and over , Alzheimer Disease/pathology , Alzheimer Disease/physiopathology , Amygdala/pathology , Antihypertensive Agents/therapeutic use , Arteriosclerosis/epidemiology , Arteriosclerosis/pathology , Atrophy , Cephalometry , Cohort Studies , Comorbidity , Diastole , Female , Follow-Up Studies , Hippocampus/pathology , Humans , Hypertension/drug therapy , Hypertension/pathology , Hypotension/epidemiology , Magnetic Resonance Imaging , Male , Middle Aged , Netherlands
17.
J Neurol Neurosurg Psychiatry ; 75(9): 1304-8, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15314121

ABSTRACT

BACKGROUND: White matter lesions (WML) in elderly people co-occur with hypertension, depression, and cognitive impairment. Little is known about the density and distribution of WML in normal elderly people, whether they occur randomly in the aging brain or tend to cluster in certain areas, or whether patterns of WML aggregation are linked to clinical symptoms. OBJECTIVES: To describe patterns of WML distribution in a large representative population of elderly people using non-inferential cluster analysis; and to determine the extent to which such patterns are associated with clinical symptomatology. METHOD: A population sample of 1077 elderly people was recruited. Multiple analysis of correspondence followed by automatic classification methods was used to explore overall patterns of WML distribution. Correspondence was then sought between these patterns and a range of cerebrovascular, psychiatric, and neurological symptoms. RESULTS: Three distinct patterns of spatial localisation within the brain were observed, corresponding to distinct clusters of clinical symptoms. In particular WML aggregation in temporal and occipital areas was associated with greater age, hypertension, late onset depressive disorder, poor global cognitive function, and overall WML frequency. CONCLUSIONS: WML localisation is not random in the aging brain, and their distribution is associated with age and the presence of clinical symptoms. Age differences suggest there may be patterns of progression across time; however, this requires confirmation from longitudinal imaging studies.


Subject(s)
Aging/psychology , Brain Diseases/complications , Brain Diseases/psychology , Brain/pathology , Cognition Disorders/drug therapy , Aged , Aged, 80 and over , Cluster Analysis , Cohort Studies , Depression/complications , Depression/etiology , Female , Humans , Hypertension/complications , Hypertension/etiology , Magnetic Resonance Imaging , Male , Middle Aged
18.
Neurology ; 62(9): 1533-9, 2004 May 11.
Article in English | MEDLINE | ID: mdl-15136677

ABSTRACT

OBJECTIVE: To evaluate the concordance of a volumetric method for measuring white matter lesion (WML) change with visual rating scales. METHODS: The authors selected a stratified sample of 20 elderly people (mean age 72 years, range 61 to 88 years) with an MRI examination at baseline and at 3-year follow-up from the community-based Rotterdam Scan Study (RSS). Four raters assessed WML change with four different visual rating scales: the Fazekas scale, the Scheltens scale, the RSS scale, and a new visual rating scale that was designed to measure change in WML. The authors assessed concordance with a volumetric method with scatter plots and correlations, and interobserver agreement with intraclass correlation coefficients. RESULTS: For assessment of change in WML, the Fazekas, Scheltens, and periventricular part of the RSS scale showed little correlation with volumetrics, and low interobserver agreement. The authors' new WML change scale and the subcortical part of the RSS scale showed good correlation with volumetrics. After additional training, the new WML change scale showed good interobserver agreement for measuring WML change. CONCLUSIONS: Commonly used visual rating scales are not well suited for measuring change in white matter lesion severity. The authors' new white matter lesion change scale is more accurate and precise, and may be of use in studies focusing on progression of white matter lesions.


Subject(s)
Brain Diseases/pathology , Brain/pathology , Magnetic Resonance Imaging/statistics & numerical data , Aged , Aged, 80 and over , Brain Diseases/diagnosis , Diagnosis, Computer-Assisted/statistics & numerical data , Disease Progression , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Middle Aged , Observer Variation , Research Design , Sensitivity and Specificity , Severity of Illness Index
19.
J Neurol Neurosurg Psychiatry ; 75(5): 733-6, 2004 May.
Article in English | MEDLINE | ID: mdl-15090569

ABSTRACT

OBJECTIVE: To study whether lower arterial oxygen saturation (SaO(2)) and chronic obstructive pulmonary disease (COPD) are associated with cerebral white matter lesions and lacunar infarcts. METHODS: We measured SaO(2) twice with a pulse oximeter, assessed the presence of COPD, and performed MRI in 1077 non-demented people from a general population (aged 60-90 years). We rated periventricular white matter lesions (on a scale of 0-9) and approximated a total subcortical white matter lesion volume (range 0-29.5 ml). All analyses were adjusted for age and sex and additionally for hypertension, diabetes, body mass index, pack years smoked, cholesterol, haemoglobin, myocardial infarction, and left ventricular hypertrophy. RESULTS: Lower SaO(2) was independent of potential confounders associated with more severe periventricular white matter lesions (score increased by 0.12 per 1% decrease in SaO(2) (95% confidence interval 0.01 to 0.23)). Participants with COPD had more severe periventricular white matter lesions than those without (adjusted mean difference in score 0.70 (95% confidence interval 0.23 to 1.16)). Lower SaO(2) and COPD were not associated with subcortical white matter lesions or lacunar infarcts. CONCLUSION: Lower SaO(2) and COPD are associated with more severe periventricular white matter lesions.


Subject(s)
Brain Infarction/complications , Brain Infarction/metabolism , Brain , Oxygen/metabolism , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/metabolism , Aged , Body Mass Index , Brain/blood supply , Brain/metabolism , Brain/pathology , Brain Infarction/pathology , Cholesterol/blood , Diabetes Mellitus/epidemiology , Female , Hemoglobins/metabolism , Humans , Hypertension/epidemiology , Hypertrophy, Left Ventricular/epidemiology , Hypertrophy, Left Ventricular/pathology , Magnetic Resonance Imaging , Male , Myocardial Infarction/epidemiology , Oximetry/methods , Smoking/epidemiology
20.
Diabetologia ; 46(12): 1604-10, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14595538

ABSTRACT

AIM/HYPOTHESIS: Type 2 diabetes increases the risk not only of vascular dementia but also of Alzheimer's disease. The question remains whether diabetes increases the risk of Alzheimer's disease by diabetic vasculopathy or whether diabetes influences directly the development of Alzheimer neuropathology. In vivo, hippocampal and amygdalar atrophy on brain MRI are good, early markers of the degree of Alzheimer neuropathology. We investigated the association between diabetes mellitus, insulin resistance and the degree of hippocampal and amygdalar atrophy on magnetic resonance imaging (MRI) accounting for vascular pathology. METHODS: Data was obtained in a population-based study of elderly subjects without dementia between 60 to 90 years of age. The presence of diabetes mellitus and, in non-diabetic subjects, insulin resistance was assessed for 506 participants in whom hippocampal and amygdalar volumes on MRI were measured. We assessed the degree of vascular morbidity by rating carotid atherosclerosis, and brain white matter lesions and infarcts on MRI. RESULTS: Subjects with diabetes mellitus had more hippocampal and amygdalar atrophy on MRI compared to subjects without diabetes mellitus. Furthermore, increasing insulin resistance was associated with more amygdalar atrophy on MRI. The associations were not due to vascular morbidity being more pronounced in persons with diabetes mellitus. CONCLUSIONS/INTERPRETATION: Type 2 diabetes is associated with hippocampal and amygdalar atrophy, regardless of vascular pathology. This could suggest that Type 2 diabetes directly influences the development of Alzheimer neuropathology.


Subject(s)
Diabetes Mellitus, Type 2/pathology , Magnetic Resonance Imaging , Temporal Lobe/pathology , Aged , Atrophy , Carotid Stenosis/epidemiology , Diabetic Angiopathies/epidemiology , Female , Hippocampus/anatomy & histology , Hippocampus/pathology , Humans , Male
SELECTION OF CITATIONS
SEARCH DETAIL