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1.  Definitions of dementia and predementia states in Alzheimer's disease and vascular cognitive impairment: consensus from the Canadian conference on diagnosis of dementia 
Alzheimer's Research & Therapy  2013;5(Suppl 1):S2.
There have been several newly proposed sets of diagnostic criteria for Alzheimer's disease/mild cognitive impairment, advanced by the National Institute of Aging/Alzheimer's Association working groups in 2011 and by the International Working Group in 2007 and 2010. These sets each aim to provide broader disease stage coverage with incorporation of disease biomarkers into the diagnostic process. They have focused particular attention on the earlier identification of disease with focus on the preclinical and predementia stages. This paper reviews these diagnostic criteria and provides 2012 consensus recommendations from the Canadian Consensus Conference on the Diagnosis and Treatment of Dementia on their applications in both clinical and research settings.
doi:10.1186/alzrt198
PMCID: PMC3981054  PMID: 24565215
2.  Rivastigmine: a placebo controlled trial of twice daily and three times daily regimens in patients with Alzheimer's disease 
Objective
To evaluate the efficacy and safety of rapidly titrated rivastigmine administered twice (BID) or three times (TID) daily in patients with mild to moderate Alzheimer's disease (AD).
Methods
This was a 26 week international, randomised, double blind, placebo controlled study in which 678 patients with probable AD received placebo or rivastigmine 2–12 mg/day BID or TID. Primary outcome measures included the cognitive subscale of the AD Assessment Scale (ADAS‐cog) and categorical analysis of the Clinician Interview Based Impression of Change incorporating caregiver information (CIBIC‐Plus). Secondary outcomes were the CIBIC‐Plus change from baseline, Progressive Deterioration Scale, ADAS‐cogA, Mini‐Mental State Examination and Global Deterioration Scale.
Results
At week 26, mean rivastigmine dose was 9.6 (2.76) mg/day in the TID group and 8.9 (2.93) mg/day in the BID group. Mean ADAS‐cog changes from baseline in the TID and BID rivastigmine treated groups were −0.2 (SD 7.3) and 1.2 (SD 7.2) versus 2.8 (SD 7.2) for the placebo group (p<0.05). Differences between rivastigmine TID and placebo on the CIBIC‐Plus categorical responder analysis were significant (31% vs 19%; p<0.05, intention to treat). No significant differences were seen between BID and placebo for this outcome measure. Adverse events were predominantly gastrointestinal, occurring mainly during dose titration. Withdrawal because of adverse events accounted for 17% of BID, 11% of TID and 9% of placebo patients.
Conclusions
Rivastigmine administered as a BID or TID regimen significantly benefited cognitive, function and global performances in AD patients. The TID regimen showed a tendency for superior tolerability and permitted titration to higher doses, an outcome that is significant as the efficacy of rivastigmine is dose related.
doi:10.1136/jnnp.2006.099424
PMCID: PMC2117538  PMID: 17353259
4.  Clinical and pathological features of familial frontotemporal dementia caused by C9ORF72 mutation on chromosome 9p 
Brain  2012;135(3):709-722.
Frontotemporal dementia and amyotrophic lateral sclerosis are closely related clinical syndromes with overlapping molecular pathogenesis. Several families have been reported with members affected by frontotemporal dementia, amyotrophic lateral sclerosis or both, which show genetic linkage to a region on chromosome 9p21. Recently, two studies identified the FTD/ALS gene defect on chromosome 9p as an expanded GGGGCC hexanucleotide repeat in a non-coding region of the chromosome 9 open reading frame 72 gene (C9ORF72). In the present study, we provide detailed analysis of the clinical features and neuropathology for 16 unrelated families with frontotemporal dementia caused by the C9ORF72 mutation. All had an autosomal dominant pattern of inheritance. Eight families had a combination of frontotemporal dementia and amyotrophic lateral sclerosis while the other eight had a pure frontotemporal dementia phenotype. Clinical information was available for 30 affected members of the 16 families. There was wide variation in age of onset (mean = 54.3, range = 34–74 years) and disease duration (mean = 5.3, range = 1–16 years). Early diagnoses included behavioural variant frontotemporal dementia (n = 15), progressive non-fluent aphasia (n = 5), amyotrophic lateral sclerosis (n = 9) and progressive non-fluent aphasia–amyotrophic lateral sclerosis (n = 1). Heterogeneity in clinical presentation was also common within families. However, there was a tendency for the phenotypes to converge with disease progression; seven subjects had final clinical diagnoses of both frontotemporal dementia and amyotrophic lateral sclerosis and all of those with an initial progressive non-fluent aphasia diagnosis subsequently developed significant behavioural abnormalities. Twenty-one affected family members came to autopsy and all were found to have transactive response DNA binding protein with Mr 43 kD (TDP-43) pathology in a wide neuroanatomical distribution. All had involvement of the extramotor neocortex and hippocampus (frontotemporal lobar degeneration-TDP) and all but one case (clinically pure frontotemporal dementia) had involvement of lower motor neurons, characteristic of amyotrophic lateral sclerosis. In addition, a consistent and relatively specific pathological finding was the presence of neuronal inclusions in the cerebellar cortex that were ubiquitin/p62-positive but TDP-43-negative. Our findings indicate that the C9ORF72 mutation is a major cause of familial frontotemporal dementia with TDP-43 pathology, that likely accounts for the majority of families with combined frontotemporal dementia/amyotrophic lateral sclerosis presentation, and further support the concept that frontotemporal dementia and amyotrophic lateral sclerosis represent a clinicopathological spectrum of disease with overlapping molecular pathogenesis.
doi:10.1093/brain/awr354
PMCID: PMC3286328  PMID: 22344582
frontotemporal dementia; frontotemporal lobar degeneration; amyotrophic lateral sclerosis; C9ORF72, TDP-43
5.  Prediction of conversion from mild cognitive impairment to Alzheimer's disease dementia based upon biomarkers and neuropsychological test performance 
Neurobiology of Aging  2010;33(7):1203-1214.e2.
The current study tested the accuracy of primary MRI and cerebrospinal fluid (CSF) biomarker candidates and neuropsychological tests for predicting the conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD) dementia. In a cross-validation paradigm, predictor models were estimated in the training set of AD (N = 81) and elderly control subjects (N = 101). A combination of CSF t-tau/Aβ1-4 ratio and MRI biomarkers or neuropsychological tests (free recall and trail making test B (TMT-B)) showed the best statistical fit in the AD vs. HC comparison, reaching a classification accuracy of up to 64% when applied to the prediction of MCI conversion (3.3-year observation interval, mean = 2.3 years). However, several single-predictor models showed a predictive accuracy of MCI conversion comparable to that of any multipredictor model. The best single predictors were right entorhinal cortex (prediction accuracy = 68.5% (95% CI (59.5, 77.4))) and TMT-B test (prediction accuracy 64.6% (95% CI (55.5, 73.4%))). In conclusion, short-term conversion to AD is predicted by single marker models to a comparable degree as by multimarker models in amnestic MCI subjects.
doi:10.1016/j.neurobiolaging.2010.10.019
PMCID: PMC3328615  PMID: 21159408
Alzheimer's disease; Dementia; Mild cognitive impairment; Mild cognitive impairment (MCI); Autopsy-confirmation; Biomarkers; Early detection; Cerebrospinal fluid; Cerebrospinal fluid (CSF); Aβ1-42; Tau; p-tau; MRI; Hippocampus; Volumetry; Entorhinal cortex; Prodromal; ADNI
6.  Genetic and Clinical Features of Progranulin-Associated Frontotemporal Lobar Degeneration 
Archives of neurology  2011;68(4):488-497.
Objective
To assess the relative frequency of unique mutations and their associated characteristics in 97 individuals with mutations in progranulin (GRN), an important cause of frontotemporal lobar degeneration (FTLD).
Participants and Design
A 46-site International Frontotemporal Lobar Degeneration Collaboration was formed to collect cases of FTLD with TAR DNA-binding protein of 43-kDa (TDP-43)–positive inclusions (FTLD-TDP). We identified 97 individuals with FTLD-TDP with pathogenic GRN mutations (GRN+ FTLD-TDP), assessed their genetic and clinical characteristics, and compared them with 453 patients with FTLD-TDP in which GRN mutations were excluded (GRN− FTLD-TDP). No patients were known to be related. Neuropathologic characteristics were confirmed as FTLD-TDP in 79 of the 97 GRN+ FTLDTDP cases and all of the GRN− FTLD-TDP cases.
Results
Age at onset of FTLD was younger in patients with GRN+ FTLD-TDP vs GRN− FTLD-TDP (median, 58.0 vs 61.0 years; P<.001), as was age at death (median, 65.5 vs 69.0 years; P<.001). Concomitant motor neuron disease was much less common in GRN+ FTLDTDP vs GRN− FTLD-TDP (5.4% vs 26.3%; P<.001). Fifty different GRN mutations were observed, including 2 novel mutations: c.139delG (p.D47TfsX7) and c.378C>A (p.C126X). The 2 most common GRN mutations were c.1477C>T (p.R493X, found in 18 patients, representing 18.6% of GRN cases) and c.26C>A (p.A9D, found in 6 patients, representing 6.2% of cases). Patients with the c.1477C>T mutation shared a haplotype on chromosome 17; clinically, they resembled patients with other GRN mutations. Patients with the c.26C>A mutation appeared to have a younger age at onset of FTLD and at death and more parkinsonian features than those with other GRN mutations.
Conclusion
GRN+ FTLD-TDP differs in key features from GRN− FTLD-TDP.
doi:10.1001/archneurol.2011.53
PMCID: PMC3160280  PMID: 21482928
7.  The diagnosis of mild cognitive impairment due to Alzheimer’s disease: Recommendations from the National Institute on Aging-Alzheimer’s Association workgroups on diagnostic guidelines for Alzheimer’s disease 
The National Institute on Aging and the Alzheimer’s Association charged a workgroup with the task of developing criteria for the symptomatic predementia phase of Alzheimer’s disease (AD), referred to in this article as mild cognitive impairment due to AD. The workgroup developed the following two sets of criteria: (1) core clinical criteria that could be used by healthcare providers without access to advanced imaging techniques or cerebrospinal fluid analysis, and (2) research criteria that could be used in clinical research settings, including clinical trials. The second set of criteria incorporate the use of biomarkers based on imaging and cerebrospinal fluid measures. The final set of criteria for mild cognitive impairment due to AD has four levels of certainty, depending on the presence and nature of the biomarker findings. Considerable work is needed to validate the criteria that use biomarkers and to standardize biomarker analysis for use in community settings.
doi:10.1016/j.jalz.2011.03.008
PMCID: PMC3312027  PMID: 21514249
Mild cognitive impairment; AD dementia; Diagnosis
8.  Anterior brain glucose hypometabolism predates dementia in progranulin mutation carriers 
Neurology  2013;81(15):1322-1331.
Objective:
In this prospective cohort study, we investigated cerebral glucose metabolism reductions on [18F]-fluorodeoxyglucose (FDG)-PET in progranulin (GRN) mutation carriers prior to frontotemporal dementia (FTD) onset.
Methods:
Nine mutation carriers (age 51.5 ± 13.5 years) and 11 noncarriers (age 52.7 ± 9.5 years) from 5 families with FTD due to GRN mutations underwent brain scanning with FDG-PET and MRI and clinical evaluation. Normalized FDG uptake values were calculated with reference to the pons. PET images were analyzed with regions of interest (ROI) and statistical parametric mapping (SPM) approaches.
Results:
Compared with noncarriers, GRN mutation carriers had a lowered anterior-to-posterior (AP) ratio of FDG uptake (0.86 ± 0.09 vs 0.92 ± 0.05) and less left-right asymmetry, consistent with an overall pattern of right anterior cerebral hypometabolism. This pattern was observed regardless of whether they were deemed clinically symptomatic no dementia or asymptomatic. Individual ROIs with lowered FDG uptake included right anterior cingulate, insula, and gyrus rectus. SPM analysis supported and extended these findings, demonstrating abnormalities in the right and left medial frontal regions, right insular cortex, right precentral and middle frontal gyri, and right cerebellum. Right AP ratio was correlated with cognitive and clinical scores (modified Mini-Mental State Examination r = 0.74; Functional Rating Scale r = −0.73) but not age and years to estimated onset in mutation carriers.
Conclusion:
The frontotemporal lobar degenerative process associated with GRN mutations appears to begin many years prior to the average age at FTD onset (late 50s–early 60s). Right medial and ventral frontal cortex and insula may be affected in this process but the specific regional patterns associated with specific clinical variants remain to be elucidated.
doi:10.1212/WNL.0b013e3182a8237e
PMCID: PMC3806924  PMID: 24005336
9.  rs5848 Polymorphism and Serum Progranulin Level 
Objective
To assess the influence of rs5848 polymorphism in serum progranulin (PGRN) level in a cohort of subjects with Alzheimer and related dementias from a tertiary referral clinic.
Background
Mutations in the GRN gene cause autosomal dominant frontotemporal dementia (FTD) with TDP-43 pathology (FTLD-TDP) through haploinsufficiency. It has recently been shown that homozygous carriers of the T-allele of rs5848 have an elevated risk developing FTD, and this polymorphism may play a role in the pathogenesis of other dementia by modifying progranulin level. We hypothesize that genotype of rs5848 may influence serum PGRN level in AD, FTD, and other dementias.
Methods
Blood samples were obtained from patients with cognitive impairment and dementia referred to a tertiary dementia clinic, as well as samples from a cohort of healthy controls. Serum PGRN level was measured using an ELISA assay, and rs5848 genotype was determined by a TaqMan assay.
Results
We found that rs5848 SNP significantly influenced serum PGRN level, with TT genotype having the lowest levels, CC the highest. This relationship is observed in each of the subgroups. We also confirmed that GRN mutation carriers had significantly lower serum PGRN levels than all other groups.
Conclusions
The rs5848 polymorphism significantly influences serum PGRN with TT carriers having a lower level of serum PGRN then CT and CC carriers. This is consistent with the finding that miR-659 binding to the high risk T allele of rs5848 may augment translational inhibition of GRN and alter risk of FTD and possibly other dementias.
doi:10.1016/j.jns.2010.10.009
PMCID: PMC3085023  PMID: 21047645
Frontotemporal Dementia; Progranulin; PGRN; GRN; rs5848; genetic polymorphism; biomarker
10.  Sortilin-Mediated Endocytosis Determines Levels of the Fronto-Temporal Dementia Protein, Progranulin 
Neuron  2010;68(4):654-667.
SUMMARY
The most common inherited form of Fronto-Temporal Lobar Degeneration (FTLD) known stems from Progranulin (GRN) mutation, and exhibits TDP-43 plus ubiquitin aggregates. Despite the causative role of GRN haploinsufficiency in FTLD-TDP, the neurobiology of this secreted glycoprotein is unclear. Here, we examined PGRN binding to the cell surface. PGRN binds to cortical neurons via its C-terminus, and unbiased expression cloning identifies Sortilin (Sort1) as a binding site. Sort1−/− neurons exhibit reduced PGRN binding. In the CNS, Sortilin is expressed by neurons and PGRN is most strongly expressed by activated microglial cells after injury. Sortilin rapidly endocytoses and delivers PGRN to lysosomes. Mice lacking Sortilin have elevations in brain and serum PGRN levels of 2.5- to 5-fold. The 50% PGRN decrease causative in FTLD-TDP cases is mimicked in GRN+/− mice, and is fully normalized by Sort1 ablation. Sortilin-mediated PGRN endocytosis is likely to play a central role in FTLD-TDP pathophysiology.
doi:10.1016/j.neuron.2010.09.034
PMCID: PMC2990962  PMID: 21092856
11.  Effectiveness of Donepezil in Reducing Clinical Worsening in Patients with Mild-to-Moderate Alzheimer's Disease 
Background
Therapeutic endpoints based on reduced clinical worsening represent clinically relevant and realistic goals for patients suffering from progressive neurodegenerative disorders such as Alzheimer's disease (AD).
Methods
Data from 906 patients (388 receiving placebo; 518 receiving donepezil) with mild-to-moderate AD [Mini-Mental State Examination (MMSE) score 10–27] were pooled from 3 randomized, double-blind placebo-controlled studies. Clinical worsening was defined as decline in (1) cognition (MMSE), (2) cognition and global ratings (Clinician's Interview-Based Impression of Change plus Caregiver Input/Gottfries-Bråne-Steen scale) or (3) cognition, global ratings and function (various functional measures).
Results
At week 24, lower percentages of donepezil-treated patients than placebo patients met the criteria for clinical worsening, regardless of the definition. The odds of declining were significantly reduced for donepezil-treated versus placebo patients (p < 0.0001; all definitions). Among patients meeting criteria for clinical worsening, mean declines in MMSE scores were greater for placebo than donepezil-treated patients.
Conclusion
In this population, donepezil treatment was associated with reduced odds of clinical worsening of AD symptoms. Moreover, patients worsening on donepezil were likely to experience less cognitive decline than expected if left untreated. This suggests that AD patients showing clinical worsening on donepezil may still derive benefits compared with placebo/untreated patients.
doi:10.1159/000241877
PMCID: PMC3202931  PMID: 19786776
Donepezil; Alzheimer's disease; Cognition; Global function; Clinical worsening
12.  Common variants at 7p21 are associated with frontotemporal lobar degeneration with TDP-43 inclusions 
Van Deerlin, Vivianna M. | Sleiman, Patrick M. A. | Martinez-Lage, Maria | Chen-Plotkin, Alice | Wang, Li-San | Graff-Radford, Neill R | Dickson, Dennis W. | Rademakers, Rosa | Boeve, Bradley F. | Grossman, Murray | Arnold, Steven E. | Mann, David M.A. | Pickering-Brown, Stuart M. | Seelaar, Harro | Heutink, Peter | van Swieten, John C. | Murrell, Jill R. | Ghetti, Bernardino | Spina, Salvatore | Grafman, Jordan | Hodges, John | Spillantini, Maria Grazia | Gilman, Sid' | Lieberman, Andrew P. | Kaye, Jeffrey A. | Woltjer, Randall L. | Bigio, Eileen H | Mesulam, Marsel | al-Sarraj, Safa | Troakes, Claire | Rosenberg, Roger N. | White, Charles L. | Ferrer, Isidro | Lladó, Albert | Neumann, Manuela | Kretzschmar, Hans A. | Hulette, Christine Marie | Welsh-Bohmer, Kathleen A. | Miller, Bruce L | Alzualde, Ainhoa | de Munain, Adolfo Lopez | McKee, Ann C. | Gearing, Marla | Levey, Allan I. | Lah, James J. | Hardy, John | Rohrer, Jonathan D. | Lashley, Tammaryn | Mackenzie, Ian R.A. | Feldman, Howard H. | Hamilton, Ronald L. | Dekosky, Steven T. | van der Zee, Julie | Kumar-Singh, Samir | Van Broeckhoven, Christine | Mayeux, Richard | Vonsattel, Jean Paul G. | Troncoso, Juan C. | Kril, Jillian J | Kwok, John B.J. | Halliday, Glenda M. | Bird, Thomas D. | Ince, Paul G. | Shaw, Pamela J. | Cairns, Nigel J. | Morris, John C. | McLean, Catriona Ann | DeCarli, Charles | Ellis, William G. | Freeman, Stefanie H. | Frosch, Matthew P. | Growdon, John H. | Perl, Daniel P. | Sano, Mary | Bennett, David A. | Schneider, Julie A. | Beach, Thomas G. | Reiman, Eric M. | Woodruff, Bryan K. | Cummings, Jeffrey | Vinters, Harry V. | Miller, Carol A. | Chui, Helena C. | Alafuzoff, Irina | Hartikainen, Päivi | Seilhean, Danielle | Galasko, Douglas | Masliah, Eliezer | Cotman, Carl W. | Tuñón, M. Teresa | Martínez, M. Cristina Caballero | Munoz, David G. | Carroll, Steven L. | Marson, Daniel | Riederer, Peter F. | Bogdanovic, Nenad | Schellenberg, Gerard D. | Hakonarson, Hakon | Trojanowski, John Q. | Lee, Virginia M.-Y.
Nature genetics  2010;42(3):234-239.
Frontotemporal lobar degeneration (FTLD) is the second most common cause of presenile dementia. The predominant neuropathology is FTLD with TAR DNA binding protein (TDP-43) inclusions (FTLD-TDP)1. FTLD-TDP is frequently familial resulting from progranulin (GRN) mutations. We assembled an international collaboration to identify susceptibility loci for FTLD-TDP, using genome-wide association (GWA). We found that FTLD-TDP associates with multiple SNPs mapping to a single linkage disequilibrium (LD) block on 7p21 that contains TMEM106B in a GWA study (GWAS) on 515 FTLD-TDP cases. Three SNPs retained genome-wide significance following Bonferroni correction; top SNP rs1990622 (P=1.08×10−11; odds ratio (OR) minor allele (C) 0.61, 95% CI 0.53-0.71). The association replicated in 89 FTLD-TDP cases (rs1990622; P=2×10−4). TMEM106B variants may confer risk by increasing TMEM106B expression. TMEM106B variants also contribute to genetic risk for FTLD-TDP in patients with GRN mutations. Our data implicate TMEM106B as a strong risk factor for FTLD-TDP suggesting an underlying pathogenic mechanism.
doi:10.1038/ng.536
PMCID: PMC2828525  PMID: 20154673
13.  An Exploration of Cognitive Subgroups in Alzheimer's Disease 
Introduction
Heterogeneity is observed in the patterns of cognition in Alzheimer's disease (AD). Such heterogeneity might suggest the involvement of different aetiological pathways or different host responses to pathology.
Method
627 subjects with mild/moderate AD underwent cognitive assessment with the Mini-Mental Status Exam (MMSE) and the Dementia Rating Scale-2 (DRS-2). Latent class analysis (LCA) was performed on cognition subscale data to identify and characterise cognitive subgroups. Clinical, demographic and genetic factors were explored for association with class membership.
Results
LCA suggested the existence of four subgroups; one group with mild and another with severe global impairment across the cognitive domains, one group with primary impairments in attention and construction, and another group with primary deficits in memory and orientation. Education, disease duration, age, APOE ε4 status, gender, presence of grasp reflex, white matter changes and early or prominent visuospatial impairment were all associated with class membership.
Conclusions
Our results support the existence of heterogeneity in patterns of cognitive impairment in AD. Our observation of classes characterised by predominant deficits in attention/construction and memory respectively deserves further exploration as does the association between membership in the attention/construction class and APOE ε4 negative status.
doi:10.1017/S1355617709991160
PMCID: PMC2903844  PMID: 19958568
dementia; latent class analysis; cognition; Mattis Dementia Rating Scale-2; Mini-Mental State Examination; apolipoprotein E
14.  Diagnosis and treatment of dementia: 2. Diagnosis 
Background
Dementia can now be accurately diagnosed through clinical evaluation, cognitive screening, basic laboratory evaluation and structural imaging. A large number of ancillary techniques are also available to aid in diagnosis, but their role in the armamentarium of family physicians remains controversial. In this article, we provide physicians with practical guidance on the diagnosis of dementia based on recommendations from the Third Canadian Consensus Conference on the Diagnosis and Treatment of Dementia, held in March 2006.
Methods
We developed evidence-based guidelines using systematic literature searches, with specific criteria for study selection and quality assessment, and a clear and transparent decision-making process. We selected studies published from January 1996 to December 2005 that pertained to key diagnostic issues in dementia. We graded the strength of evidence using the criteria of the Canadian Task Force on Preventive Health Care.
Results
Of the 1591 articles we identified on all aspects of dementia diagnosis, 1095 met our inclusion criteria; 620 were deemed to be of good or fair quality. From a synthesis of the evidence in these studies, we made 32 recommendations related to the diagnosis of dementia. There are clinical criteria for diagnosing most forms of dementia. A standard diagnostic evaluation can be performd by family physicians over multiple visits. It involves a clinical history (from patient and caregiver), a physical examination and brief cognitive testing. A list of core laboratory tests is recommended. Structural imaging with computed tomography or magnetic resonance imaging is recommended in selected cases to rule out treatable causes of dementia or to rule in cerebrovascular disease. There is insufficient evidence to recommend routine functional imaging, measurement of biomarkers or neuropsychologic testing.
Interpretation
The diagnosis of dementia remains clinically integrative based on history, physical examination and brief cognitive testing. A number of core laboratory tests are also recommended. Structural neuroimaging is advised in selected cases. Other diagnostic approaches, including functional neuroimaging, neuropsychological testing and measurement of biomarkers, have shown promise but are not yet recommended for routine use by family physicians.
doi:10.1503/cmaj.070798
PMCID: PMC2267847  PMID: 18362376

Results 1-14 (14)