Alzheimer Disease: van der Flier WM

van der Flier WM, Barkhof F, Scheltens P. · Department of Neurology and Alzheimer Center, Vrije Universiteit Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. · Ann N Y Acad Sci. · Pubmed #17413024 No free full text.

Abstract: Atrophy and cerebrovascular disease are the two most important magnetic resonance imaging (MRI) characteristics in the evaluation of dementia. On MRI, atrophy is the primary hallmark of neurodegenerative dementias including Alzheimer's disease (AD), while vascular dementia is characterized by the presence of ischemic vascular damage, such as territorial infarcts, lacunes, and white matter hyperintensities. Evidence is accumulating that vascular factors play an important role in the development of cognitive decline at old age and clinical AD. In the present article we present results of four recent MRI studies suggesting the additional involvement of small vessel disease in neurodegenerative disorders. Atrophy in the medial temporal lobe, as typically observed in AD, and small vessel disease often coincide. In terms of clinical significance, their effects may even be synergistic. The strict distinction between AD and vascular dementia is often artificial, as most patients suffer from both disorders to some extent. For the future, we see an important role for MRI in identifying those different compartments, regardless of clinical classification. Treatment could be directed by (and evaluated through) MRI patterns, rather than a diagnostic label.

de Leeuw FE, van Norden AG, van der Flier WM, Olde Rikkert MG, Scheltens P. · Universitair Medisch Centrum St Radboud, Huispostnummer 326, Postbus gIoI, 6500 HB Nijmegen. · Ned Tijdschr Geneeskd. · Pubmed #16398165 No free full text.

Abstract: There is increasing evidence that vascular risk factors including hypertension, high cholesterol, hyperhomocysteinaemia and diabetes mellitus are connected to the risk of Alzheimer's disease (AD). The risk of AD may be reduced by the treatment of hypertension prior to onset of cognitive impairment. One small randomised clinical trial has provided some evidence of beneficial effects on cognition of cholesterol-lowering drugs such as the statins in patients with AD. Treatment of hypertension, hyperhomocysteinaemia and diabetes mellitus with the aim of halting the progression of cognitive decline in AD is still under study and results are awaited. For the time being findings from the trials carried out thus far should be interpreted with care due to methodological shortcomings, both in study design and execution. In order to investigate the role of vascular risk factors both in the aetiology and treatment of AD, large prospective randomised trials with long-term follow-up of AD patients who have been diagnosed using revised uniform diagnostic criteria that take the heterogeneity of the disease into account, are necessary.

Staekenborg SS, van der Flier WM, van Straaten EC, Lane R, Barkhof F, Scheltens P. · Department of Neurology and Alzheimer Centre, Vrije University Medical Centre, Amsterdam, The Netherlands. · Stroke. · Pubmed #18096841 links to  free full text

Abstract: BACKGROUND AND PURPOSE: The aim of this study was to describe the prevalence of a number of neurological signs in a large population of patients with vascular dementia (VaD) and to compare the relative frequency of specific neurological signs dependent on type of cerebrovascular disease. METHODS: Seven hundred six patients with VaD (NINDS-AIREN) were included from a large multicenter clinical trial (registration number NCT00099216). At baseline neurological examination, the presence of 16 neurological signs was assessed. Based on MRI, patients were classified as having large vessel VaD (18%; large territorial or strategical infarcts on MRI), small vessel VaD (74%; white matter hyperintensities [WMH], multiple lacunes, bilateral thalamic lesions on MRI), or a combination of both (8%). RESULTS: A median number of 4.5 signs per patient was presented (maximum 16). Reflex asymmetry was the most prevalent symptom (49%), hemianopia was most seldom presented (10%). Measures of small vessel disease were associated with an increased prevalence of dysarthria, dysphagia, parkinsonian gait disorder, rigidity, and hypokinesia and as well to hemimotor dysfunction. By contrast, in the presence of a cerebral infarct, aphasia, hemianopia, hemimotor dysfunction, hemisensory dysfunction, reflex asymmetry, and hemiplegic gait disorder were more often observed. CONCLUSIONS: The specific neurological signs demonstrated by patients with VaD differ according to type of imaged cerebrovascular disease. Even in people who meet restrictive VaD criteria, small vessel disease is often seen with more subtle signs, including extrapyramidal signs, whereas large vessel disease is more often related to lateralized sensorimotor changes and aphasia.

Mattsson N, Zetterberg H, Hansson O, Andreasen N, Parnetti L, Jonsson M, Herukka SK, van der Flier WM, Blankenstein MA, Ewers M, Rich K, Kaiser E, Verbeek M, Tsolaki M, Mulugeta E, Rosén E, Aarsland D, Visser PJ, Schröder J, Marcusson J, de Leon M, Hampel H, Scheltens P, Pirttilä T, Wallin A, Jönhagen ME, Minthon L, Winblad B, Blennow K. · Institute of Neuroscience and Physiology, Department of Neurochemistry and Psychiatry, The Sahlgrenska Academy at University of Gothenburg, Mölndal, Sweden. · JAMA. · Pubmed #19622817 No free full text.

Abstract: CONTEXT: Small single-center studies have shown that cerebrospinal fluid (CSF) biomarkers may be useful to identify incipient Alzheimer disease (AD) in patients with mild cognitive impairment (MCI), but large-scale multicenter studies have not been conducted. OBJECTIVE: To determine the diagnostic accuracy of CSF beta-amyloid(1-42) (Abeta42), total tau protein (T-tau), and tau phosphorylated at position threonine 181 (P-tau) for predicting incipient AD in patients with MCI. DESIGN, SETTING, AND PARTICIPANTS: The study had 2 parts: a cross-sectional study involving patients with AD and controls to identify cut points, followed by a prospective cohort study involving patients with MCI, conducted 1990-2007. A total of 750 individuals with MCI, 529 with AD, and 304 controls were recruited by 12 centers in Europe and the United States. Individuals with MCI were followed up for at least 2 years or until symptoms had progressed to clinical dementia. MAIN OUTCOME MEASURES: Sensitivity, specificity, positive and negative likelihood ratios (LRs) of CSF Abeta42, T-tau, and P-tau for identifying incipient AD. RESULTS: During follow-up, 271 participants with MCI were diagnosed with AD and 59 with other dementias. The Abeta42 assay in particular had considerable intersite variability. Patients who developed AD had lower median Abeta42 (356; range, 96-1075 ng/L) and higher P-tau (81; range, 15-183 ng/L) and T-tau (582; range, 83-2174 ng/L) levels than MCI patients who did not develop AD during follow-up (579; range, 121-1420 ng/L for Abeta42; 53; range, 15-163 ng/L for P-tau; and 294; range, 31-2483 ng/L for T-tau, P < .001). The area under the receiver operating characteristic curve was 0.78 (95% confidence interval [CI], 0.75-0.82) for Abeta42, 0.76 (95% CI, 0.72-0.80) for P-tau, and 0.79 (95% CI, 0.76-0.83) for T-tau. Cut-offs with sensitivity set to 85% were defined in the AD and control groups and tested in the MCI group, where the combination of Abeta42/P-tau ratio and T-tau identified incipient AD with a sensitivity of 83% (95% CI, 78%-88%), specificity 72% (95% CI, 68%-76%), positive LR, 3.0 (95% CI, 2.5-3.4), and negative LR, 0.24 (95% CI, 0.21-0.28). The positive predictive value was 62% and the negative predictive value was 88%. CONCLUSIONS: This multicenter study found that CSF Abeta42, T-tau, and P-tau identify incipient AD with good accuracy, but less accurately than reported from single-center studies. Intersite assay variability highlights a need for standardization of analytical techniques and clinical procedures.

Verwey NA, van der Flier WM, Blennow K, Clark C, Sokolow S, De Deyn PP, Galasko D, Hampel H, Hartmann T, Kapaki E, Lannfelt L, Mehta PD, Parnetti L, Petzold A, Pirttila T, Saleh L, Skinningsrud A, Swieten JC, Verbeek MM, Wiltfang J, Younkin S, Scheltens P, Blankenstein MA. · Department of Clinical Chemistry, VU University Medical Center, , HV, The Netherlands. · Ann Clin Biochem. · Pubmed #19342441 No free full text.

Abstract: BACKGROUND: Different cerebrospinal fluid (CSF) amyloid-beta 1-42 (Abeta(1-42)), total Tau (Tau) and Tau phosphorylated at threonine 181 (P-Tau) levels are reported, but currently there is a lack of quality control programmes. The aim of this study was to compare the measurements of these CSF biomarkers, between and within centres. METHODS: Three CSF-pool samples were distributed to 13 laboratories in 2004 and the same samples were again distributed to 18 laboratories in 2008. In 2004 six laboratories measured Abeta(1-42), Tau and P-Tau and seven laboratories measured one or two of these marker(s) by enzyme-linked immunosorbent assays (ELISAs). In 2008, 12 laboratories measured all three markers, three laboratories measured one or two marker(s) by ELISAs and three laboratories measured the markers by Luminex. RESULTS: In 2004, the ELISA intercentre coefficients of variance (interCV) were 31%, 21% and 13% for Abeta(1-42), Tau and P-Tau, respectively. These were 37%, 16% and 15%, respectively, in 2008. When we restricted the analysis to the Innotest (N = 13) for Abeta(1-42), lower interCV were calculated (22%). The centres that participated in both years (N = 9) showed interCVs of 21%, 15% and 9% and intra-centre coefficients (intraCV) of variance of 25%,18% and 7% in 2008. CONCLUSIONS: The highest variability was found for Abeta(1-42). The variabilities for Tau and P-Tau were lower in both years. The centres that participated in both years showed a high intraCV comparable to their interCV, indicating that there is not only a high variation between but also within centres. Besides a uniform standardization of (pre)analytical procedures, the same assay should be used to decrease the inter/intracentre variation.

van der Vlies AE, Verwey NA, Bouwman FH, Blankenstein MA, Klein M, Scheltens P, van der Flier WM. · Department of Neurology and Alzheimer Center, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. · Neurology. · Pubmed #19307538 No free full text.

Abstract: OBJECTIVE: To investigate the relationship between CSF biomarkers and cognitive profiles in Alzheimer disease (AD). METHODS: We included 177 patients with AD. Digit Span, Visual Association Test (VAT), VAT object naming, Trail Making Test (TMT), and category fluency were used to assess cognitive functions. Disease severity was assessed using Mini-Mental State Examination; functional impairment was rated by Clinical Dementia Rating. In CSF, levels of amyloid-beta 1-42 (Abeta(1-42)), tau, and tau phosphorylated at threonine 181 (p-tau) were measured. K-means cluster analysis was performed with the three biomarkers to obtain three clusters. Multivariate analysis of variance for repeated measures was performed with CSF cluster as between-subjects factor, neuropsychological z scores as within-subjects variable, and age, sex, and education as covariates. RESULTS: Cluster 1 consisted of 88 patients (49%) with relatively high levels of Abeta(1-42) and low levels of tau and p-tau. Cluster 2 contained 72 patients (41%) with relatively low levels of Abeta(1-42) and high levels of tau and p-tau. Cluster 3 was made up of 17 patients (10%) with low levels of Abeta(1-42) and very high levels of tau and p-tau. No differences between clusters on age, sex, education, APOE genotype, disease duration, functional impairment, or disease severity were found. Patients in cluster 3 performed worse on VAT, TMT-A and -B, and fluency. CONCLUSIONS: Clusters of CSF biomarker levels are related to cognitive profiles in Alzheimer disease. A subgroup of patients with extremely high CSF levels of tau and tau phosphorylated at threonine 181 shows a distinct cognitive profile with more severe impairment of memory, mental speed, and executive functions, which cannot be explained by disease severity.

Henneman WJ, Sluimer JD, Barnes J, van der Flier WM, Sluimer IC, Fox NC, Scheltens P, Vrenken H, Barkhof F. · Department of Radiology, VU University Medical Center, Amsterdam, The Netherlands. · Neurology. · Pubmed #19289740 No free full text.

Abstract: OBJECTIVE: To investigate the added value of hippocampal atrophy rates over whole brain volume measurements on MRI in patients with Alzheimer disease (AD), patients with mild cognitive impairment (MCI), and controls. METHODS: We included 64 patients with AD (67 +/- 9 years; F/M 38/26), 44 patients with MCI (71 +/- 6 years; 21/23), and 34 controls (67 +/- 9 years; 16/18). Two MR scans were performed (scan interval: 1.8 +/- 0.7 years; 1.0 T), using a coronal three-dimensional T1-weighted gradient echo sequence. At follow-up, 3 controls and 23 patients with MCI had progressed to AD. Hippocampi were manually delineated at baseline. Hippocampal atrophy rates were calculated using regional, nonlinear fluid registration. Whole brain baseline volumes and atrophy rates were determined using automated segmentation and registration tools. RESULTS: All MRI measures differed between groups (p < 0.005). For the distinction of MCI from controls, larger effect sizes of hippocampal measures were found compared to whole brain measures. Between MCI and AD, only whole brain atrophy rate differed significantly. Cox proportional hazards models (variables dichotomized by median) showed that within all patients without dementia, hippocampal baseline volume (hazard ratio [HR]: 5.7 [95% confidence interval: 1.5-22.2]), hippocampal atrophy rate (5.2 [1.9-14.3]), and whole brain atrophy rate (2.8 [1.1-7.2]) independently predicted progression to AD; the combination of low hippocampal volume and high atrophy rate yielded a HR of 61.1 (6.1-606.8). Within patients with MCI, only hippocampal baseline volume and atrophy rate predicted progression. CONCLUSION: Hippocampal measures, especially hippocampal atrophy rate, best discriminate mild cognitive impairment (MCI) from controls. Whole brain atrophy rate discriminates Alzheimer disease (AD) from MCI. Regional measures of hippocampal atrophy are the strongest predictors of progression to AD.

Kester MI, Blankenstein MA, Bouwman FH, van Elk EJ, Scheltens P, van der Flier WM. · Alzheimer Center and Department of Neurology, VU University Medical Center Amsterdam, Amsterdam, The Netherlands. · J Alzheimers Dis. · Pubmed #19276554 No free full text.

Abstract: The object of this study was to elucidate the effect of age in the relationship between APOE genotype and CSF biomarkers amyloid-beta1-42 (Abeta42), total tau (tau) and tau phosphorylated at threonine 181 (ptau-181) in AD and controls. 302 AD patients and 174 controls were categorized into APOE epsilon4 carriers and non-carriers, and into younger and older (65years). In controls, older age and APOE epsilon4 were independently associated with lower Abeta42 and higher tau and ptau-181 levels (p < 0.05). For tau and ptau-181, there were also interactions (p < 0.10): older carriers had higher levels than older non-carriers, without effect for younger controls. In AD, APOE epsilon4 genotype had a main effect on Abeta42, but there was also an interaction: older carriers had lower Abeta42 than older non-carriers, without effect for younger AD patients (p < 0.05). For tau and ptau-181, there were only interactions: older carriers had higher levels than older non-carriers, while younger AD patients showed the opposite (p 0.05). Association between CSF biomarkers and APOE genotype were modified by age in both controls and AD patients. This suggests that cognitively healthy APOE epsilon4 carriers are more prone to develop AD pathology with aging. For AD patients, this provides support for the existence of subtypes within the disease.

Staekenborg SS, Koedam EL, Henneman WJ, Stokman P, Barkhof F, Scheltens P, van der Flier WM. · Department of Neurology, Alzheimer Center, Vrije Universiteit Medical Center, Amsterdam, The Netherlands. · Stroke. · Pubmed #19228848 No free full text.

Abstract: BACKGROUND AND PURPOSE: We sought to determine the predictive value of magnetic resonance imaging measures of vascular disease (white matter hyperintensities [WMHs], lacunes, microbleeds, and infarcts) compared with atrophy on the progression of mild cognitive impairment to dementia. METHODS: We included 152 consecutive patients with mild cognitive impairment. Baseline magnetic resonance imaging was used to determine the presence of medial temporal lobe atrophy and vascular disease (presence of lacunes, microbleeds, and infarcts was determined, and WMHs were rated on a semiquantitative scale). Patients were followed up for 2+/-1 years. RESULTS: Seventy-two (47%) patients progressed to dementia during follow-up. Of these, 56 (37%) patients were diagnosed with Alzheimer's disease, and 16 (10%) patients were diagnosed with a non-Alzheimer dementia (including vascular dementia, frontotemporal lobar degeneration, and Parkinson dementia). Converters were older and had a lower Mini-Mental State Examination score at baseline. On baseline magnetic resonance imaging, patients who progressed to a non-Alzheimer dementia showed more severe WMHs and had a higher prevalence of lacunes in the basal ganglia and microbleeds compared with nonconverters. Cox proportional-hazard models showed that, adjusted for age and sex, baseline medial temporal lobe atrophy (hazard ratio=2.9; 95% CI, 1.7 to 5.3), but not vascular disease, was associated with progression to Alzheimer's disease. By contrast, deep WMHs (hazard ratio=5.7; 95% CI, 1.2 to 26.7) and periventricular hyperintensities (hazard ratio=6.5; 95% CI, 1.4 to 29.8) predicted progression to non-Alzheimer dementia. Furthermore, microbleeds (hazard ratio=2.6; 95% CI, 0.9 to 7.5) yielded a >2-fold increased, though nonsignificant, risk of non-Alzheimer dementia. CONCLUSIONS: Medial temporal lobe atrophy and markers of cerebrovascular disease predict the development of different types of dementia in mild cognitive impairment patients.

Benisty S, Gouw AA, Porcher R, Madureira S, Hernandez K, Poggesi A, van der Flier WM, Van Straaten EC, Verdelho A, Ferro J, Pantoni L, Inzitari D, Barkhof F, Fazekas F, Chabriat H, Anonymous00042. · Department of Neurology, Lariboisière-Fernand Widal Hospital, APHP, Paris, France. · J Neurol Neurosurg Psychiatry. · Pubmed #19211595 No free full text.

Abstract: OBJECTIVES: In cerebral small vessel disease, white-matter hyperintensities (WMH) and lacunes are both related to cognition. Still, their respective contribution in older people remains unclear. The purpose of this study is to assess the topographic distribution of lacunes and determine whether it has an impact on cognitive functions in a sample of non-disabled patients with age-related white-matter changes. METHODS: Data were drawn from the baseline evaluation of the LADIS (Leucoaraioisis and Disability study) cohort of non-disabled subjects beyond 65 years of age. The neuropsychological evaluation was based on the Mini Mental Status Examination (MMSE), a modified Alzheimer Diseases Assessment Scale for global cognitive functions, and compound Z scores for memory, executive functions, speed and motor control. WMH were rated according to the Fazekas scale; the number of lacunes was assessed in the following areas: lobar white matter, putamen/pallidum, thalamus, caudate nucleus, internal/external capsule, infratentorial areas. An analysis of covariance was performed after adjustment for possible confounders. RESULTS: Among 633 subjects, 47% had at least one lacune (31% at least one within basal ganglia). The presence of lacunes in the thalamus was associated with lower scores of MMSE (beta = -0.61; p = 0.043), and worse compound scores for speed and motor control (beta = -0.25; p = 0.006), executive functions (beta = -0.19; p = 0.022) independently of the cognitive impact of WMH. There was also a significant negative association between the presence of lacunes in putamen/pallidum and the memory compound Z score (beta = -0.13; p = 0.038). By contrast, no significant negative association was found between cognitive parameters and the presence of lacunes in internal capsule, lobar white matter and caudate nucleus. CONCLUSION: In non-disabled elderly subjects with leucoaraisosis, the location of lacunes within subcortical grey matter is a determinant of cognitive impairment, independently of the extent of WMH.

Tolboom N, Yaqub M, van der Flier WM, Boellaard R, Luurtsema G, Windhorst AD, Barkhof F, Scheltens P, Lammertsma AA, van Berckel BN. · Department of Nuclear Medicine and PET Research, VU University Medical Centre, Amsterdam, The Netherlands. · J Nucl Med. · Pubmed #19164243 No free full text.

Abstract: 11C-Pittsburgh Compound-B (11C-PIB) and 18F-(2-(1-{6-[(2-[18F]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene) (18F-FDDNP) have been developed as PET tracers for in vivo imaging of pathology in Alzheimer's disease (AD). The purpose of this study was to directly compare these tracers in patients with AD, patients with mild cognitive impairment (MCI), and healthy controls. METHODS: Paired 11C-PIB and 18F-FDDNP scans were acquired in 14 patients with AD, 11 patients with amnestic MCI, and 13 controls. For both tracers, parametric images of binding potential (BPND) were generated. Global cortical BPND was assessed using ANOVA. In addition, regional patterns of BPND were compared between diagnostic groups using ANOVA for repeated measures. RESULTS: Global cortical BPND of 11C-PIB showed higher binding in patients with AD than in controls and patients with MCI. 18F-FDDNP uptake was higher in patients with AD than in controls, but MCI could not be distinguished from AD or from controls. Global BPND values of both tracers were moderately correlated (r=0.45; P=0.005). In MCI, BPND of 11C-PIB showed a bimodal distribution, whereas values for 18F-FDDNP were more widespread, with more MCI patients demonstrating increased uptake. Regional 11C-PIB binding showed different patterns across diagnostic groups, as AD patients showed an overall increase in binding, with the lowest binding in the medial temporal lobe. With 18F-FDDNP, patterns were similar across diagnostic groups. For all groups, highest values were observed in the medial temporal lobe. CONCLUSION: Differences in BPND between patients with AD, patients with MCI, and controls were more pronounced for 11C-PIB. The difference in regional binding, the moderate correlation, and the discrepant findings in MCI suggest that they measure related, but different, characteristics of the disease.

Henneman WJ, Sluimer JD, Cordonnier C, Baak MM, Scheltens P, Barkhof F, van der Flier WM. · Department of Radiology and Alzheimer Center, VU University Medical Center, Amsterdam, The Netherlands. · Stroke. · Pubmed #19109551 No free full text.

Abstract: BACKGROUND AND PURPOSE: MRI biomarkers play an important role in the diagnostic work-up of dementia, but their prognostic value is less well-understood. We investigated if simple MRI rating scales predict mortality in a memory clinic population. METHODS: We included 1138 consecutive patients attending our memory clinic. Diagnostic categories were: subjective complaints (n=220), mild cognitive impairment (n=160), Alzheimer disease (n=357), vascular dementia (n=46), other dementia (n=136), and other diagnosis (n=219). Baseline MRIs were assessed using visual rating scales for medial temporal lobe atrophy (range, 0-4), global cortical atrophy (range, 0-3), and white matter hyperintensities (range, 0-3). Number of microbleeds and presence of infarcts were recorded. Cox-regression models were used to calculate the risk of mortality. RESULTS: Mean follow-up duration was 2.6 (+/-1.9) years. In unadjusted models, all MRI markers except infarcts predicted mortality. After adjustment for age, sex, and diagnosis, white matter hyperintensities, and microbleeds predicted mortality (white matter hyperintensities: hazard ratio [HR], 1.2; 95% CI, 1.0-1.4; microbleeds: HR, 1.02 95% CI, 1.00-1.03; categorized: HR, 1.5; 95% CI, 1.1-2.0). The predictive effect of global cortical atrophy was restricted to younger subjects (HR, 1.7; 95% CI, 1.2-2.6). An interaction between microbleeds and global cortical atrophy indicated that mortality was especially high in patients with both microbleeds and global cortical atrophy. CONCLUSIONS: Simple MRI biomarkers, in addition to their diagnostic use, have a prognostic value with respect to mortality in a memory clinic population. Microbleeds were the strongest predictor of mortality.

Liedorp M, van der Flier WM, Hoogervorst EL, Scheltens P, Stam CJ. · Alzheimer Center, Department of Neurology, VU University Medical Center, Amsterdam, The Netherlands. · Dement Geriatr Cogn Disord. · Pubmed #19088474 No free full text.

Abstract: AIM: To describe associations of abnormalities in the electroencephalogram (EEG) with the most prevalent diagnoses in a memory clinic cohort. METHODS: Associations between visual EEG findings and diagnoses in 1,116 consecutive patients [382 Alzheimer's disease (AD), 274 subjective complaints, 190 mild cognitive impairment (MCI), 118 psychiatric disorder, 61 frontotemporal lobar degeneration, 53 vascular dementia (VaD), 38 dementia with Lewy bodies (DLB)] were determined by prevalence ratio (PR). RESULTS: Diagnoses of subjective complaints [PR = 1.6; 95% confidence interval (CI) = 1.4-1.9] and psychiatric disorder (1.4; 95% CI = 1.1-1.9) were associated with a normal EEG, while subjects with both focal and diffuse EEG disturbances were more likely to have DLB (3.5; 95% CI = 2.1-5.6), VaD (2.3; 95% CI = 1.4-3.6) or AD (1.5; 95% CI = 1.3-1.8). Subjects with only diffuse EEG abnormalities were more likely to have AD (PR = 1.5; 95% CI = 1.3-1.9). The prevalence of MCI was higher among those with only focal EEG abnormalities (PR = 1.3; 95% CI = 1.0-1.7). CONCLUSIONS: A normal EEG argues for subjective complaints or psychiatric diagnosis. An EEG with only focal abnormalities supports MCI. An EEG with only diffuse abnormalities argues for AD. An EEG with both focal and diffuse abnormalities argues for DLB, VaD or AD.

Verwey NA, Schuitemaker A, van der Flier WM, Mulder SD, Mulder C, Hack CE, Scheltens P, Blankenstein MA, Veerhuis R. · Department of Neurology, Alzheimer Center, VU University Medical Center, Amsterdam, The Netherlands. · Dement Geriatr Cogn Disord. · Pubmed #19052452 No free full text.

Abstract: BACKGROUND: Serum amyloid P component (SAP), present in amyloid-beta (Abeta) plaques in Alzheimer's disease (AD), may protect Abeta deposits against proteolysis, thereby promoting plaque formation. The aim was to investigate if SAP levels in cerebrospinal fluid (CSF) and serum can be used to discriminate controls, AD and mild cognitive impairment (MCI) patients, and to identify incipient AD among MCI patients. METHODS: SAP levels in CSF and serum were determined in 30 controls, 67 MCI and 144 AD patients. At follow-up, 39 MCI patients had progressed to dementia, while 25 had remained stable (mean follow-up time: 2.6 +/- 1.0 and 2.1 +/- 0.8 years). RESULTS: Cross-sectionally no differences were found in SAP levels in CSF and serum between the groups. MCI patients that had progressed to dementia at follow-up had lower CSF SAP levels (13 mg/l, range 3.3-199.3 mg/l) than MCI nonprogressors (20.2 mg/l, range 7.0-127.7 mg/l; p < 0.05). A low CSF SAP level was associated with a 2-fold increased risk of progression to AD (hazard ratio = 2.2; 95% confidence interval = 0.9-5.4). CONCLUSION: Our data suggest that measurement of CSF SAP levels can aid in the identification of incipient AD among MCI patients.

Gouw AA, Seewann A, Vrenken H, van der Flier WM, Rozemuller JM, Barkhof F, Scheltens P, Geurts JJ. · Department of Neurology, Alzheimer Center and Image Analysis Center, Vrije Universiteit Medical Center, Amsterdam, The Netherlands. · Brain. · Pubmed #18927145 No free full text.

Abstract: White matter hyperintensities (WMH) are frequently seen on T(2)-weighted MRI scans of elderly subjects with and without Alzheimer's disease. WMH are only weakly and inconsistently associated with cognitive decline, which may be explained by heterogeneity of the underlying neuropathological substrates. The use of quantitative MRI could increase specificity for these neuropathological changes. We assessed whether post-mortem quantitative MRI is able to reflect differences in neuropathological correlates of WMH in tissue samples obtained post-mortem from Alzheimer's disease patients and from non-demented elderly. Thirty-three formalin-fixed, coronal brain slices from 11 Alzheimer's disease patients (mean age: 83 +/- 10 years, eight females) and 15 slices from seven non-demented controls (mean age: 78 +/- 10 years, four females) with WMH were scanned at 1.5 T using qualitative (fluid-attenuated inversion recovery, FLAIR) and quantitative MRI [diffusion tensor imaging (DTI) including estimation of apparent diffusion coefficient (ADC) and fractional anisotropy (FA), and T(1)-relaxation time mapping based on flip-angle array). A total of 104 regions of interest were defined on FLAIR images in WMH and normal appearing white matter (NAWM). Neuropathological examination included (semi-)quantitative assessment of axonal density (Bodian), myelin density (LFB), astrogliosis (GFAP) and microglial activation (HLA-DR). Patient groups (Alzheimer's disease versus controls) and tissue types (WMH versus NAWM) were compared with respect to QMRI and neuropathological measures. Overall, Alzheimer's disease patients had significantly lower FA (P < 0.01) and higher T(1)-values than controls (P = 0.04). WMH showed lower FA (P < 0.01) and higher T(1)-values (P < 0.001) than NAWM in both patient groups. A significant interaction between patient group and tissue type was found for the T(1) measurements, indicating that the difference in T(1)-relaxation time between NAWM and WMH was larger in Alzheimer's disease patients than in non-demented controls. All neuropathological measures showed differences between WMH and NAWM, although the difference in microglial activation was specific for Alzheimer's disease. Multivariate regression models revealed that in Alzheimer's disease, axonal density was an independent determinant of FA, whereas T(1) was independently determined by axonal and myelin density and microglial activation. Quantitative MRI techniques reveal differences in WMH between Alzheimer's disease and non-demented elderly, and are able to reflect the severity of the neuropathological changes involved.

Kramer G, van der Flier WM, de Langen C, Blankenstein MA, Scheltens P, Stam CJ. · Department of Neurology, Alzheimer Centre, VU University Medical Center, PO Box 7057, De Boelelaan 1118, 1007 MB Amsterdam, Noord Holland, The Netherlands. · Clin Neurophysiol. · Pubmed #18848805 No free full text.

Abstract: OBJECTIVE: We examined the relation between Apolipoprotein E epsilon4 allele (ApoE epsilon4) genotype and functional connectivity measured by Electroencephalography (EEG) in patients with Alzheimer's disease (AD) and patients with subjective complaints (SC). METHODS: We included 43 patients with AD (age (SD)=74.2 (4.0), m/f=22/21; 30 of ApoE epsilon4 carriers) and 21 patients with SC (age (SD)=73.2 (5.2), m/f=13/8; 7 ApoE epsilon4 carriers) for this study. Resting state EEGs were recorded in all subjects. Synchronisation likelihood (SL) between local cortical areas was compared in the alpha and beta band according to ApoE epsilon4 status and diagnosis. RESULTS: ApoE epsilon4 carriers had higher SL values in lower and upper alpha band, in both diagnostic groups. In upper alpha band and beta band AD patients had lower SL than patients with SC, was irrespective of ApoE status. CONCLUSION: The effects of AD and ApoE epsilon4 on functional connectivity are opposite and independent. SIGNIFICANCE: The observed increase in SL in both AD and patients with SC carrying ApoE epsilon4 suggests a strong genetic impact of ApoE epsilon4 on brain function.

Koedam EL, Pijnenburg YA, Deeg DJ, Baak MM, van der Vlies AE, Scheltens P, van der Flier WM. · Department of Neurology and Alzheimer Center, VU University Medical Center, Amsterdam, The Netherlands. · Dement Geriatr Cogn Disord. · Pubmed #18679029 No free full text.

Abstract: BACKGROUND/AIMS: Our objective was to compare the mortality risks of patients with early- and late-onset dementia with non-demented controls of the same age range and to analyse the mortality risks in subtypes of dementia. METHODS: We included 1,203 subjects from our memory clinic. Patients with dementia were subdivided into 2 groups, with early- (<65 years) or late-onset dementia (>or=65 years), and compared with non-demented controls of the same age range. We used Cox proportional hazard models to estimate mortality risks. RESULTS: When compared to non-demented controls of the same age range, the patients with early-onset dementia had a strongly elevated mortality risk [hazard ratio (95% confidence interval) = 43.3 (3.1-600.4)], while those with late-onset dementia had a moderately increased mortality risk compared to older controls [hazard ratio (95% confidence interval) = 3.4 (1.8-6.2)]. An additional analysis showed that, adjusted for age, Alzheimer's disease seemed to have the most benign course, with a fourfold increased mortality risk. Dementia with Lewy bodies and vascular dementia (frequently seen at older age) and frontotemporal lobar degeneration and 'other dementias' (often found at younger age) had a six- to eightfold increased mortality risk. CONCLUSION: Dementia is a risk factor for death. Especially in young patients the impact of dementia on mortality is high.

Staekenborg SS, van Straaten EC, van der Flier WM, Lane R, Barkhof F, Scheltens P. · Dept. of Neurology and Alzheimer Centre, Vrije Universiteit Medical Centre, 7057, 1007 MB Amsterdam, The Netherlands. · J Neurol. · Pubmed #18677637 No free full text.

Abstract: OBJECTIVE: The aim of this study was a cross-sectional comparison of clinical and MRI characteristics and risk factor profiles between patients with small vessel disease (lacunae and white matter hyperintensities) and large vessel disease (large territorial or strategical infarcts) in a large cohort of VaD patients. METHODS: Patients with VaD (NINDS-AIREN) were included in a large multicenter treatment trial (the VantagE study). All patients were examined by a neurologist and interviewed about their medical history. Based on MRI, patients were classified as having large vessel VaD, small vessel VaD, or a combination. Other MRI characteristics included white matter hyperintensities (WMH), medial temporal lobe atrophy (MTA) and general cortical atrophy. RESULTS: Of the 706 patients, 522 (74 %) had small vessel disease, 126 (18 %) had large vessel disease and 58 (8 %) had both. Patients with small vessel disease were older and less educated, and showed more cortical and medial temporal lobe atrophy than patients with large vessel disease. The most prevalent vascular risk factors (hypertension, diabetes and smoking) were equally distributed between the different types of VaD. However, patients with large vessel disease had more hypercholesterolemia and cardiac risk factors compared to patients with small vessel disease. CONCLUSION: Cerebrovascular disease underlying VaD consists in the majority of small vessel disease and in about one fifth of large vessel disease. This study demonstrates heterogeneity between these two groups with regard to risk factor profile and atrophy scores on MRI.

Ballard C, Sauter M, Scheltens P, He Y, Barkhof F, van Straaten EC, van der Flier WM, Hsu C, Wu S, Lane R. · Wolfson Centre for Age-Related Diseases, King's College, London, UK. · Curr Med Res Opin. · Pubmed #18674411 No free full text.

Abstract: OBJECTIVE: The aim was to evaluate the efficacy, safety and tolerability of rivastigmine capsules in patients diagnosed with probable vascular dementia (VaD). METHODS: VantagE (Vascular Dementia trial studying Exelon) was a 24-week, multicentre, double-blind study. VaD patients aged 50-85 years were randomized to rivastigmine capsules (3-12 mg/day) or placebo. Efficacy assessments included global and cognitive performances, activities of daily living and neuropsychiatric symptoms. Adverse events were recorded. Additional exploratory analyses determined whether heterogeneity in pathologies and symptoms extended to differential treatment effects. TRIAL REGISTRATION: NCT00099216. RESULTS: 710 patients were randomized. Rivastigmine demonstrated superiority over placebo on three measures of cognitive performance (Vascular Dementia Assessment Scale, Alzheimer's Disease Assessment Scale cognitive subscale, Mini-Mental State Examination; all p< or = 0.05, intent-to-treat population [ITT]), but not other outcomes. Predominant adverse events were nausea and vomiting. Exploratory analyses indicated that older patients (> or =75 years old), assumed more likely to also have Alzheimer's disease (AD) pathology, demonstrated significant cognitive responses to rivastigmine and a safety profile similar to that seen in AD patients. Younger patients, assumed less likely to have concomitant AD pathology, showed no efficacy response and were associated with slight elevations of blood pressure, cerebrovascular accidents and mortality. Rivastigmine-placebo differences in patients with, versus those without, medial temporal atrophy (also suggestive of concomitant AD) showed a numerical difference similar to that seen between the older versus younger patients, but did not attain statistical significance. CONCLUSION: Consistent with trials evaluating other cholinesterase inhibitors, rivastigmine did not provide consistent efficacy in probable VaD. The efficacy apparent on cognitive outcomes was derived from effects in older patients likely to have concomitant Alzheimer pathology. This is supportive of an existing argument that the putative cholinergic deficit in VaD reflects the presence of concomitant Alzheimer pathology.

Sluimer JD, van der Flier WM, Karas GB, Fox NC, Scheltens P, Barkhof F, Vrenken H. · Department of Diagnostic Radiology, Alzheimer Centre, Vrije Universiteit Medical Centre, Amsterdam, the Netherlands. · Radiology. · Pubmed #18574133 links to  free full text

Abstract: PURPOSE: To prospectively determine whole-brain atrophy rate in mild cognitive impairment (MCI) and Alzheimer disease (AD) and its association with cognitive decline, and investigate the risk of progression to dementia in initially nondemented patients given baseline brain volume and whole-brain atrophy rate. MATERIALS AND METHODS: This study was IRB approved; written informed consent was obtained; and included 65 AD patients (38 women, 27 men; age, 52-81 years), 45 MCI patients (22 women, 23 men; age, 56-80 years), 27 patients with subjective complaints (12 women, 15 men; age, 50-87 years), and 10 healthy controls (six women, four men; age, 53-80 years). Two magnetic resonance (MR) images were acquired at average interval of 1.8 years +/- 0.7 (standard deviation). Baseline brain volume and whole-brain atrophy rates were measured on three-dimensional T1-weighted MR images (1.0 T; single slab, 168 sections; matrix size, 256 x 256; field of view, 250 mm; voxel size, 1 x 1 x 1.5 mm; repetition time msec/echo time msec/inversion time msec, 15/7/300; and flip angle, 15 degrees ). Associations were assessed by using partial-correlations. Cox proportional hazards models were used to estimate risk of developing dementia. RESULTS: Baseline brain volume was lowest in AD but did not differ significantly between MCI, subjective complaints, and control groups (P > .38). Whole-brain atrophy rates were higher in AD (-1.9% per year +/- 0.9) than MCI (-1.2% per year +/- 0.9, P = .003) patients, who had higher whole-brain atrophy rates than patients with subjective complaints (-0.7% per year +/- 0.7, P = .03) and controls (-0.5% per year +/- 0.5, P = .05). Whole-brain atrophy rate correlated with annualized Mini-Mental State Examination (MMSE) change (r = 0.48, P < .001), while baseline volume did not (r = 0.11, P = .22). Cox models showed that-after correction for age, sex, and baseline MMSE-a higher whole-brain atrophy rate was associated with an increased risk of progression to dementia (highest vs lowest tertile [hazard ratio, 3.6; 95% confidence interval: 1.2, 11.4]). CONCLUSION: Whole-brain atrophy rate was strongly associated with cognitive decline. In nondemented participants, a high whole-brain atrophy rate was associated with an increased risk of progression to dementia.

Pijnenburg YA, Strijers RL, Made YV, van der Flier WM, Scheltens P, Stam CJ. · Alzheimer Center and Department of Neurology, VU Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. · Clin Neurophysiol. · Pubmed #18490193 No free full text.

Abstract: OBJECTIVE: To investigate the presence of EEG abnormalities in frontotemporal lobar degeneration (FTLD) in comparison with Alzheimer's disease (AD) and non-demented individuals with subjective memory complaints (SMC), using an elaborated visual EEG rating scale; furthermore, to investigate whether assessment of resting-state functional connectivity of the EEG is superior to visual evaluation in distinguishing between FTLD, AD and non-demented controls. METHODS: EEGs of 15 patients with FTLD, 20 with AD and 23 individuals with SMC were visually compared using the Grand Total EEG (GTE) score. The synchronization likelihood (SL) as a measure of functional connectivity between different EEG channels was calculated for the 0.5-4Hz, 4-8Hz, 8-10Hz, 10-13Hz, 13-30Hz and 30-45Hz frequency bands. Patients had mild to moderate dementia. RESULTS: In AD, as expected, the GTE revealed significant differences from FTLD and SMC, indicating more EEG slowing and loss of reactivity. Patients with FTLD, however, could not be discriminated from individuals with SMC by the GTE score. Analysis of resting-state functional connectivity showed decreased SL in AD compared to both FTLD and SMC in the lower and higher alpha frequency band and decreased SL in AD compared to SMC in the beta frequency band, whereas no differences between FTLD and AD or SMC were found. CONCLUSIONS: In patients with mild to moderate FTLD both the visually rated EEG and EEG measures of resting-state functional connectivity are normal. SIGNIFICANCE: Although widespread neuronal degeneration takes place in frontotemporal lobar degeneration, this is not reflected in the EEG during the mild to moderate stages of the disease. An abnormal EEG in a mildly demented subject favours a diagnosis of AD.

Sluimer JD, Vrenken H, Blankenstein MA, Fox NC, Scheltens P, Barkhof F, van der Flier WM. · Department of Radiology and Alzheimer Centre, Vrije Universiteit Medical Centre, PO Box 7057, 1007 MB Amsterdam, The Netherlands. · Neurology. · Pubmed #18458218 No free full text.

Abstract: OBJECTIVE: To assess which baseline clinical and MRI measures influence whole-brain atrophy rates, measured from serial MR imaging. METHODS: We recruited 65 patients with Alzheimer disease (mean +/- SD age 70 +/- 8 y, 58% women, Mini-Mental State Examination [MMSE] 22 +/- 5), scanned with an average interval of 1.7 +/- 0.6 years. Whole-brain atrophy rates were used as outcome measure. Baseline normalized brain volume, hippocampal volume, and whole-brain atrophy rates were measured using three-dimensional T1-weighted imaging. The influence of age, sex, apolipoprotein E genotype (APOE), baseline MMSE, baseline hippocampal volume, and baseline normalized brain volume on whole-brain atrophy rates was assessed using linear regression. RESULTS: The mean whole-brain atrophy rate was -1.9 +/- 0.9% per year. In the multivariate model, younger age (beta [SE] = 0.03 [0.01]; p = 0.04), absence of APOE epsilon 4 (beta [SE] = 0.61 [0.28]; p = 0.03), and a low MMSE (beta [SE] = 0.11 [0.03]; p < 0.001) were associated with a higher whole-brain atrophy rate. Furthermore, a relatively spared hippocampus predicted faster decline for patients with a smaller baseline brain volume (p = 0.09), and with a lower MMSE (p = 0.07). Finally, a smaller brain volume was associated with a higher rate of atrophy in younger patients (p = 0.03). CONCLUSIONS: Our results suggest it is possible to characterize a subgroup of patients with Alzheimer disease (AD) who are at risk of faster loss of brain volume. Patients with more generalized, rather than focal hippocampal atrophy, who often have an onset before the age of 65, and are APOE epsilon 4 negative, seem to be at risk of faster whole-brain atrophy rates than the more commonly seen patients with AD, who are older, are APOE epsilon 4 positive, and have pronounced hippocampal atrophy.

van der Flier WM, Pijnenburg YA, Schoonenboom SN, Dik MG, Blankenstein MA, Scheltens P. · Alzheimer Center, Department of Neurology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands. · Dement Geriatr Cogn Disord. · Pubmed #18401171 No free full text.

Abstract: AIM: To describe the distribution of apolipoprotein E (APOE) genotypes in a cohort of memory clinic patients. METHODS: We included 749 memory clinic patients. Diagnoses were made in a multidisciplinary consensus meeting and the APOE genotype was determined. The community-based cohort of the Longitudinal Aging Study Amsterdam was used as control population (n = 2,233). RESULTS: In the memory clinic sample, there were 173 patients with subjective complaints, 125 patients with mild cognitive impairment (MCI), 251 patients with Alzheimer disease (AD), 107 patients with another type of dementia, and 93 patients with another neurologic or psychiatric diagnosis. The APOE allele distribution differed among groups. There was no difference in the prevalence of the epsilon2 allele, but there were differences in distribution of the epsilon3 and epsilon4 alleles. Compared with the control population (15%), the prevalence of APOE epsilon4 was increased among patients with subjective complaints (22%), MCI (36%), AD (42%) and other types of dementia (25%). CONCLUSION: We observed an increased prevalence of APOE epsilon4 in patients with MCI and subjective complaints. This finding is of great clinical importance as nondemented patients positive for APOE epsilon4 could be identified as being at genetic risk of AD, and for that reason monitored more closely.

Gouw AA, van der Flier WM, Fazekas F, van Straaten EC, Pantoni L, Poggesi A, Inzitari D, Erkinjuntti T, Wahlund LO, Waldemar G, Schmidt R, Scheltens P, Barkhof F, Anonymous00402. · Department of Neurology, Alzheimer Center and Image Analysis Center, Vrije Universiteit Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands. · Stroke. · Pubmed #18323505 links to  free full text

Abstract: BACKGROUND AND PURPOSE: We studied the natural course of white matter hyperintensities (WMH) and lacunes, the main MRI representatives of small vessel disease, over time and evaluated possible predictors for their development. METHODS: Baseline and repeat MRI (3-year follow-up) were collected within the multicenter, multinational Leukoaraiosis and Disability study (n=396). Baseline WMH were scored on MRI by the Fazekas scale and the Scheltens scale. WMH progression was assessed using the modified Rotterdam Progression scale (absence/presence of progression in 9 brain regions). Baseline and new lacunes were counted per region. WMH and lacunes at baseline and vascular risk factors were evaluated as predictors of WMH progression and new lacunes. RESULTS: WMH progressed (mean+/-SD=1.9+/-1.8) mostly in the subcortical white matter, where WMH was also most prevalent at baseline. The majority of new lacunes, which were found in 19% of the subjects (maximum=9), also appeared in the subcortical white matter, mainly of the frontal lobes, whereas most baseline lacunes were located in the basal ganglia. Baseline WMH and lacunes predicted both WMH progression and new lacunes. Furthermore, previous stroke, diabetes, and blood glucose were risk factors for WMH progression. Male sex, hypertension, systolic blood pressure, previous stroke, body mass index, high-density lipoprotein, and triglyceride levels were risk factors for new lacunes. CONCLUSIONS: WMH and lacunes progressed over time, predominantly in the subcortical white matter. Progression was observed especially in subjects with considerable WMH and lacunes at baseline. Moreover, the presence of vascular risk factors at baseline predicted WMH progression and new lacunes over a 3-year period.

Jelles B, Scheltens P, van der Flier WM, Jonkman EJ, da Silva FH, Stam CJ. · Department of Neurology, VU University Medical Center, P.O. Box 7057, 1007 MB Amsterdam, The Netherlands. · Clin Neurophysiol. · Pubmed #18258479 No free full text.

Abstract: OBJECTIVE: EEG coherence is decreased in Alzheimer's disease (AD), suggesting decreased interaction between brain areas. Nonlinear EEG analysis in AD points to decreased complexity of brain dynamics, implicating increased interaction. To clarify these apparently paradoxical findings from linear and nonlinear analysis, we calculated global coherence and global correlation dimension (D2), a nonlinear measure, in the EEG of patients with probable AD and controls. Our hypothesis is that these measures are related to each other when calculated in a comparable way. METHODS: From 15 patients with probable AD (mean age 63.1 years; SD 6.3) and 21 age-matched controls with subjective memory complaints (mean age 62.8; SD 12.0), band filtered EEG data were analysed in six frequency bands. For each frequency band average coherence and multichannel D2 were determined. RESULTS: ANOVA for repeated measures showed for D2 an interaction between band and group, but not for coherence. In the beta band and upper alpha band, D2 was higher in patients with probable AD compared to controls, while global coherence tended to be lower in these frequency bands in patients with probable AD. In the frequency range from theta to beta, coherence and D2 were inversely correlated without group differences. CONCLUSIONS: When calculated in comparable ways, global correlation dimension and coherence are related measures. In AD, these measures change especially in the higher frequency ranges, both pointing to decreased functional cortical connectivity. SIGNIFICANCE: Both global coherence and global correlation dimension seem to measure global connectivity, but nonlinear measures may be more sensitive. In AD, connectivity measures are not equally impaired in all frequency ranges, possibly reflecting differentiated affection of the dynamical processes responsible for the different frequency bands.