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Background:Amyloid-β plaques can co-occur with Lewy-related pathology in patients with dementia with Lewy bodies (DLB), but amyloid-β load at prodromal stages of DLB still needs to be elucidated. We investigated amyloid-β load on PET throughout the DLB continuum, from an early prodromal stage of isolated REM sleep behavior disorder (iRBD) to a stage of mild cognitive impairment with Lewy bodies (MCI-LB), and finally DLB.Methods:We performed a cross-sectional study in patients with a diagnosis of iRBD, MCI-LB, or DLB from the Mayo Clinic Alzheimer’s Disease Research Center. Amyloid-β levels were measured by Pittsburgh compound B (PiB) PET and global cortical standard uptake value ratio (SUVr) was calculated. Global cortical PiB SUVr values from each clinical group were compared to each other and to cognitively unimpaired individuals (CU; n=100) balanced on age and sex using ANCOVA. We used multiple linear regression testing for interaction to study the influences of sex andAPOEε4 status on PiB SUVr along the DLB continuum.Results:Of the 162 patients, 16 had iRBD, 64 had MCI-LB, and 82 had DLB. Compared to CU, global cortical PiB SUVr was higher in DLB (p <0.001) and MCI-LB (p=0.012). The DLB group included the highest proportion of amyloid-β positive patients (60%), followed by MCI-LB (41%), iRBD (25%), and finally CU (19%). Global cortical PiB SUVr was higher inAPOEε4 carriers compared toAPOEε4 non-carriers in MCI-LB (pp=0.049). Women had higher PiB SUVr with older age compared to men across the DLB continuum (βeta estimate=0.014,p=0.02).Conclusion:In this cross-sectional study, levels of amyloid-β load was higher further along the DLB continuum. Whereas amyloid-β levels were comparable to cognitively unimpaired individuals in iRBD, a significant elevation in amyloid-β levels was observed in the pre-dementia stage of MCI-LB and in DLB. Specifically,APOEε4 carriers had higher amyloid-β levels thanAPOEε4 non-carriers and women tended to have higher amyloid-β levels than men as they got older. These findings have important implications in targeting patients within the DLB continuum for clinical trials of disease-modifying therapies.

Alterations of cerebral glucose metabolism can be detected in patients with isolated rapid eye movement sleep behaviour disorder, a prodromal feature of neurodegenerative diseases with α-synuclein pathology. However, metabolic characteristics that determine clinical progression in isolated rapid eye movement sleep behaviour disorder and their association with other biomarkers need to be elucidated. We investigated the pattern of cerebral glucose metabolism on 18F-fluorodeoxyglucose PET in patients with isolated rapid eye movement sleep behaviour disorder, differentiating between those who clinically progressed and those who remained stable over time. Second, we studied the association between 18F-fluorodeoxyglucose PET and lower dopamine transporter availability in the putamen, another hallmark of synucleinopathies. Patients with isolated rapid eye movement sleep behaviour disorder from the Mayo Clinic Alzheimer’s Disease Research Center and Center for Sleep Medicine (n = 22) and age-and sex-matched clinically unimpaired controls (clinically unimpaired; n = 44) from the Mayo Clinic Study of Aging were included. All participants underwent 18F-fluorodeoxyglucose PET and dopamine transporter imaging with iodine 123-radiolabeled 2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane on single-photon emission computerized tomography. A subset of patients with isolated rapid eye movement sleep behaviour disorder with follow-up evaluations (n = 17) was classified as isolated rapid eye movement sleep behaviour disorder progressors (n = 7) if they developed mild cognitive impairment or Parkinson’s disease; or isolated rapid eye movement sleep behaviour disorder stables (n = 10) if they remained with a diagnosis of isolated rapid eye movement sleep behaviour disorder with no cognitive impairment. Glucose metabolic abnormalities in isolated rapid eye movement sleep behaviour disorder were determined by comparing atlas-based regional 18F-fluorodeoxyglucose PET uptake between isolated rapid eye movement sleep behaviour disorder and clinically unimpaired. Associations between 18F-fluorodeoxyglucose PET and dopamine transporter availability in the putamen were analyzed with Pearson’s correlation within the nigrostriatal pathway structures and with voxel-based analysis in the cortex. Patients with isolated rapid eye movement sleep behaviour disorder had lower glucose metabolism in the substantia nigra, retrosplenial cortex, angular cortex, and thalamus, and higher metabolism in the amygdala and entorhinal cortex compared with clinically unimpaired. Patients with isolated rapid eye movement sleep behaviour disorder who clinically progressed over time were characterized by higher glucose metabolism in the amygdala and entorhinal cortex, and lower glucose metabolism in the cerebellum compared with clinically unimpaired. Lower dopamine transporter availability in the putamen was associated with higher glucose metabolism in the pallidum within the nigrostriatal pathway; and with higher 18F-fluorodeoxyglucose uptake in the amygdala, insula, and temporal pole on a voxel-based analysis, although these associations did not survive after correcting for multiple comparisons. Our findings suggest that cerebral glucose metabolism in isolated rapid eye movement sleep behaviour disorder is characterized by hypometabolism in regions frequently affected during the prodromal stage of synucleinopathies, potentially reflecting synaptic dysfunction. Hypermetabolism is also seen in isolated rapid eye movement sleep behaviour disorder, suggesting that synaptic metabolic disruptions may be leading to a lack of inhibition, compensatory mechanisms, or microglial activation, especially in regions associated with nigrostriatal degeneration.

Introduction We examined the temporal sequence of the core features in probable dementia with Lewy bodies (DLB). Methods In 488 patients with probable DLB, the onset of each core feature and time to diagnosis was determined for men and women, and a pathologic subgroup (n = 209). Results REM sleep behavior disorder (RBD) developed before the other core features in men and women. Men were more likely to have RBD and were diagnosed with probable DLB earlier than women. Visual hallucinations developed after the other core features in men, but in women, they appeared earlier and concurrently with fluctuations and parkinsonism. Women were older and more cognitively impaired at first visit, were less likely to have RBD, more likely to be diagnosed with probable DLB later than men, and more likely to have neocortical tangles. Discussion An earlier latency to probable DLB was associated with men, RBD, and Lewy body disease without neocortical tangles.

Reduced nigrostriatal uptake on N-(3-fluoropropyl)-2β-carbomethoxy-3β-(4-[123I]iodophenyl) nortropane (123I-FP-CIT) SPECT reflects dopamine dysfunction, while other imaging markers could be complementary when used together. We assessed how well 123I-FP-CIT SPECT differentiates dementia with Lewy bodies (DLBs) from Alzheimer's disease dementia (ADem) and whether multimodal imaging provides additional value. 123I-FP-CIT SPECT, magnetic resonance imaging, [18F]2-fluoro-deoxy-D-glucose-positron emission tomography (PET), and 11C-Pittsburgh compound B (PiB)-PET were assessed in 35 participants with DLBs and 14 participants with ADem (autopsy confirmation in 9 DLBs and 4 ADem). Nigrostriatal dopamine transporter uptake was evaluated with 123I-FP-CIT SPECT using DaTQUANT software. Hippocampal volume was calculated with magnetic resonance imaging, cingulate island sign ratio with FDG-PET, and global cortical PiB retention with PiB-PET. The DaTQUANT z-scores of the putamen showed the highest c-statistic of 0.916 in differentiating DLBs from ADem among the analyzed imaging biomarkers. Adding another imaging modality to 123I-FP-CIT SPECT had c-statistics ranging from 0.968 to 0.975, and 123I-FP-CIT SPECT in combination with 2 other imaging modalities presented c-statistics ranging from 0.987 to 0.996. These findings suggest that multimodal imaging with 123I-FP-CIT SPECT aids in differentiating DLBs and ADem and in detecting comorbid Lewy-related and Alzheimer's disease pathology in patients with DLBs and ADem.

ObjectiveTo determine the clinical phenotypes associated with the β-amyloid PET and dopamine transporter imaging (123I-FP-CIT SPECT) findings in mild cognitive impairment (MCI) with the core clinical features of dementia with Lewy bodies (DLB; MCI-LB).MethodsPatients with MCI who had at least 1 core clinical feature of DLB (n = 34) were grouped into β-amyloid A+ or A− and 123I-FP-CIT SPECT D+ or D− groups based on previously established abnormality cut points for A+ with Pittsburgh compound B PET standardized uptake value ratio (PiB SUVR) ≥1.48 and D+ with putamen z score with DaTQUANT 123I-FP-CIT SPECT. Individual patients with MCI-LB fell into 1 of 4 groups: A+D+, A+D−, A−D+, or A−D−. Log-transformed PiB SUVR and putamen z score were tested for associations with patient characteristics.ResultsThe A−D+ biomarker profile was most common (38.2%), followed by A+D+ (26.5%) and A−D− (26.5%). The least common was the A+D- biomarker profile (8.8%). The A+ group was older, had a higher frequency of APOE ε4 carriers, and had a lower Mini-Mental State Examination score than the A− group. The D+ group was more likely to have probable REM sleep behavior disorder. Lower putamen DaTQUANT z scores and lower PiB SUVRs were independently associated with higher Unified Parkinson’s Disease Rating Scale-III scores.ConclusionsA majority of patients with MCI-LB are characterized by low β-amyloid deposition and reduced dopaminergic activity. β-Amyloid PET and 123I-FP-CIT SPECT are complementary in characterizing clinical phenotypes of patients with MCI-LB.

Author(s): Boeve, Bradley F; Boxer, Adam L; Rosen, Howard J; Forsberg, Leah K; Heuer, Hilary W; Brushaber, Danielle; Appleby, Brian; Biernacka, Joanna M; Bordelon, Yvette M; Botha, Hugo; Brannelly, Patrick; Dickerson, Brad C; Dickson, Dennis W; Kimiko, Domoto‐Reilly; Faber, Kelley; Fagan, Anne; Fields, Julie A; Fishman, Ann; Foroud, Tatiana M; Galasko, Doug R; Gavrilova, Ralitza H; Gendron, Tania F; Geschwind, Daniel H; Ghoshal, Nupur; Goldman, Jill; Graff‐Radford, Jonathan; Graff‐Radford, Neill R; Grant, Ian; Grossman, Murray; Hsiung, Ging‐Yuek Robin; Huang, Eric J; Huey, Edward; Irwin, David J; Jones, David T; Kantarci, Kejal; Karydas, Anna M; Kaufer, Daniel; Knopman, David S; Kramer, Joel H; Kremers, Walter K; Kornak, John; Kukull, Walter A; Lagone, Emma; Leger, Gabriel C; Litvan, Irene; Ljubenkov, Peter A; Lucente, Diane E; Mackenzie, Ian R; Manoochehri, Masood; Masdeu, Joseph C; McGinnis, Scott; Mendez, Mario F; Miller, Bruce L; Miyagawa, Toji; Nelson, Kevin M; Onyike, Chiadi U; Pantelyat, Alex; Pascual, Belen; Pearlman, Rodney; Petrucelli, Leonard; Rademakers, Rosa; Ramos, Eliana Marisa; Rankin, Katherine; Rascovsky, Katya; Rexach, Jessica E; Ritter, Aaron; Roberson, Erik D; Rojas, Julio C; Sabbagh, Marwan N; Salmon, David P; Savica, Rodolfo; Seeley, William W; Staffaroni, Adam M; Syrjanen, Jeremy; Tartaglia, Carmela; Tatton, Nadine; Taylor, Joanne; Toga, Arthur W; Weintraub, Sandra; Wheaton, Diana; Wong, Bonnie; Wszolek, Zbigniew

Our rationale was to conduct a retrospective study comparing 3 (123)I-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane ((123)I-FP-CIT) SPECT quantitative methods in patients with neurodegenerative syndromes as referenced to neuropathologic findings. Methods: (123)I-FP-CIT-SPECT and neuropathologic findings among patients with neurodegenerative syndromes from the Mayo Alzheimer Disease Research Center and Mayo Clinic Study of Aging were examined. Three (123)I-FP-CIT SPECT quantitative assessment methods—MIMneuro, DaTQUANT, and manual region-of-interest creation on a workstation—were compared with neuropathologic findings describing the presence or absence of Lewy body disease (LBD). Striatum-to-background ratios (SBRs) generated by DaTQUANT were compared with the calculated SBRs of the manual method and MIMneuro. The left and right SBRs for caudate, putamen, and striatum were evaluated with the manual method. For DaTQUANT and MIMneuro, the left, right, total, and average SBRs and z scores for whole striatum, caudate, putamen, anterior putamen, and posterior putamen were calculated. Results: The cohort included 24 patients (20 [83%] male, mean age for all patients at death, 75.4 ± 10.0 y). The antemortem clinical diagnoses were Alzheimer disease dementia (n = 6), probable dementia with Lewy bodies (n = 12), mixed Alzheimer disease dementia and probable dementia with Lewy bodies (n = 1), Parkinson disease with mild cognitive impairment (n = 2), corticobasal syndrome (n = 1), idiopathic rapid-eye-movement sleep behavior disorder (n = 1), and behavioral-variant frontotemporal dementia (n = 1). Seventeen (71%) had LBD. All 3 (123)I-FP-CIT SPECT quantitative methods had an area under the receiver-operating-characteristics curve ranging from more than 0.93 to up to 1.000 (P < 0.001) and showed excellent discrimination between LBD and non-LBD patients in each region assessed (P < 0.001). There was no significant difference between the accuracy of the regions in discriminating the 2 groups, with good discrimination for both caudate and putamen. Conclusion: All 3 (123)I-FP-CIT SPECT quantitative methods showed excellent discrimination between LBD and non-LBD patients in each region assessed, using both SBRs and z scores.

Reduced nigrostriatal uptake on (123)I-FP-CIT SPECT reflects dopamine dysfunction, while other imaging markers could be complementary when used together. We assessed how well (123)I-FP-CIT SPECT differentiates Dementia with Lewy Bodies (DLB) from Alzheimer’s Disease Dementia (ADem) and whether multimodal imaging provides additional value. (123)I-FP-CIT SPECT, MRI, FDG-PET, and PiB-PET were assessed in 35 DLB and 14 ADem participants (autopsy confirmation in 9 DLB and 4 ADem). Nigrostriatal dopamine transporter uptake was evaluated with (123)I-FP-CIT SPECT using DaTQUANT software. Hippocampal volume was calculated with MRI, cingulate island sign (CIS) ratio with FDG-PET, and global cortical PiB retention with PiB-PET. The DaTQUANT z-scores of putamen showed the highest c-statistic of 0.916 in differentiating DLB from ADem among the analyzed imaging biomarkers. Adding another imaging modality to (123)I-FP-CIT SPECT had c-statistics ranging from 0.968 to 0.975, and (123)I-FP-CIT SPECT in combination with two other imaging modalities presented c-statistics ranging from 0.987 to 0.996. These findings suggest that multimodal imaging with (123)I-FP-CIT SPECT aids in differentiating DLB and ADem, and in detecting comorbid Lewy-related and AD pathology in DLB and ADem patients.

This is an international multicentre study aimed at evaluating the combined value of dopaminergic neuroimaging and clinical features in predicting future phenoconversion of idiopathic REM sleep behaviour (iRBD) subjects to overt synucleinopathy. Nine centres sent 123I-FP-CIT-SPECT data of 344 iRBD patients and 256 controls for centralized analysis. 123I-FP-CIT-SPECT images were semiquantified using DaTQUANTTM, obtaining putamen and caudate specific to non-displaceable binding ratios (SBRs). The following clinical variables were also analysed: (i) Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale, motor section score; (ii) Mini-Mental State Examination score; (iii) constipation; and (iv) hyposmia. Kaplan-Meier survival analysis was performed to estimate conversion risk. Hazard ratios for each variable were calculated with Cox regression. A generalized logistic regression model was applied to identify the best combination of risk factors. Bayesian classifier was used to identify the baseline features predicting phenoconversion to parkinsonism or dementia. After quality check of the data, 263 iRBD patients (67.6 ± 7.3 years, 229 males) and 243 control subjects (67.2 ± 10.1 years, 110 males) were analysed. Fifty-two (20%) patients developed a synucleinopathy after average follow-up of 2 years. The best combination of risk factors was putamen dopaminergic dysfunction of the most affected hemisphere on imaging, defined as the lower value between either putamina (P

Author(s): Miyagawa, Toji; Brushaber, Danielle; Syrjanen, Jeremy; Kremers, Walter; Fields, Julie; Forsberg, Leah K; Heuer, Hilary W; Knopman, David; Kornak, John; Boxer, Adam; Rosen, Howard J; Boeve, Bradley F; Appleby, Brian; Bordelon, Yvette; Bove, Jessica; Brannelly, Patrick; Caso, Christina; Coppola, Giovanni; Dever, Reilly; Dheel, Christina; Dickerson, Bradford; Dickinson, Susan; Dominguez, Sophia; Domoto-Reilly, Kimiko; Faber, Kelley; Ferrell, Jessica; Fishman, Ann; Fong, Jamie; Foroud, Tatiana; Gavrilova, Ralitza; Gearhart, Debra; Ghazanfari, Behnaz; Ghoshal, Nupur; Goldman, Jill S; Graff-Radford, Jonathan; Graff-Radford, Neill; Grant, Ian; Grossman, Murray; Haley, Dana; Hsiung, Robin; Huey, Edward; Irwin, David; Jones, David; Jones, Lynne; Kantarci, Kejal; Karydas, Anna; Kaufer, Daniel; Kerwin, Diana; Kraft, Ruth; Kramer, Joel; Kukull, Walter; Litvan, Irene; Lucente, Diane; Lungu, Codrin; Mackenzie, Ian; Maldonado, Miranda; Manoochehri, Masood; McGinnis, Scott; McKinley, Emily; Mendez, Mario F; Miller, Bruce; Multani, Namita; Onyike, Chiadi; Padmanabhan, Jaya; Pantelyat, Alexander; Pearlman, Rodney; Petrucelli, Leonard; Potter, Madeline; Rademakers, Rosa; Ramos, Eliana M; Rankin, Kate; Rascovsky, Katya; Roberson, Erik D; Rogalski, Emily; Sengdy, Pheth; Shaw, Leslie; Tartaglia, Maria C; Tatton, Nadine; Taylor, Joanne; Toga, Arthur; Trojanowski, John Q; Wang, Ping; Weintraub, Sandra; Wong, Bonnie; Wszolek, Zbigniew | Abstract: IntroductionWe created global rating scoring rules for the CDR® plus NACC FTLD to detect and track early frontotemporal lobar degeneration (FTLD) and to conduct clinical trials in FTLD.MethodsThe CDR plus NACC FTLD rating was applied to 970 sporadic and familial participants from the baseline visit of Advancing Research and Treatment in Frontotemporal Lobar Degeneration (ARTFL)/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects (LEFFTDS). Each of the eight domains of the CDR plus NACC FTLD was equally weighed in determining the global score. An interrater reliability study was completed for 40 participants.ResultsThe CDR plus NACC FTLD showed very good interrater reliability. It was especially useful in detecting clinical features of mild non-fluent/agrammatic variant primary progressive aphasia participants.DiscussionThe global CDR plus NACC FTLD score could be an attractive outcome measure for clinical trials in symptomatic FTLD, and may be useful in natural history studies and clinical trials in FTLD spectrum disorders.

Accumulated experience supports the efficacy of allogenic haematopoietic stem cell transplantation in arresting the progression of childhood-onset cerebral form of adrenoleukodystrophy in early stages. For adulthood-onset cerebral form of adrenoleukodystrophy, however, there have been only a few reports on haematopoietic stem cell transplantation and the clinical efficacy and safety of that for adulthood-onset cerebral form of adrenoleukodystrophy remain to be established. To evaluate the clinical efficacy and safety of haematopoietic stem cell transplantation, we conducted haematopoietic stem cell transplantation on 12 patients with adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy in a single-institution-based prospective study. Through careful prospective follow-up of 45 male adrenoleukodystrophy patients, we aimed to enrol patients with adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy at early stages. Indications for haematopoietic stem cell transplantation included cerebral form of adrenoleukodystrophy or cerebello-brainstem form of adrenoleukodystrophy with Loes scores up to 13, the presence of progressively enlarging white matter lesions and/or lesions with gadolinium enhancement on brain MRI. Clinical outcomes of haematopoietic stem cell transplantation were evaluated by the survival rate as well as by serial evaluation of clinical rating scale scores and neurological and MRI findings. Clinical courses of eight patients who did not undergo haematopoietic stem cell transplantation were also evaluated for comparison of the survival rate. All the patients who underwent haematopoietic stem cell transplantation survived to date with a median follow-up period of 28.6 months (4.2–125.3 months) without fatality. Neurological findings attributable to cerebral/cerebellar/brainstem lesions became stable or partially improved in all the patients. Gadolinium-enhanced brain lesions disappeared or became obscure within 3.5 months and the white matter lesions of MRI became stable or small. The median Loes scores before haematopoietic stem cell transplantation and at the last follow-up visit were 6.0 and 5.25, respectively. Of the eight patients who did not undergo haematopoietic stem cell transplantation, six patients died 69.1 months (median period; range 16.0–104.1 months) after the onset of the cerebral/cerebellar/brainstem lesions, confirming that the survival probability was significantly higher in patients with haematopoietic stem cell transplantation compared with that in patients without haematopoietic stem cell transplantation (P = 0.0089). The present study showed that haematopoietic stem cell transplantation was conducted safely and arrested the inflammatory demyelination in all the patients with adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy when haematopoietic stem cell transplantation was conducted in the early stages. Further studies are warranted to optimize the procedures of haematopoietic stem cell transplantation for adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy., Presently, there are only a few reports on allogenic haematopoietic stem cell transplantation for adult-onset adrenoleukodystrophy. Matsukawa et al. report that survival probability was significantly higher in 12 patients with adolescent-/adult-onset cerebral/cerebello-brainstem form of adrenoleukodystrophy who underwent haematopoietic stem cell transplantation than that in 8 patients who did not undergo haematopoietic stem cell transplantation. Haematopoietic stem cell transplantation arrested the inflammatory demyelination in all the patients., Graphical Abstract Graphical Abstract

Introduction Behavior/Comportment/Personality (BEHAV) and Language (LANG) domains were added to the Clinical Dementia Rating (CDR®) for improving evaluation of patients with frontotemporal lobar degeneration (FTLD) (CDR® plus NACC FTLD). Methods We analyzed the CDR® plus NACC FTLD among participants from the baseline visit of the Advancing Research and Treatment for Frontotemporal Lobar Degeneration/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects Consortium. Results The CDR® plus NACC FTLD was able to detect early symptoms in the mildly impaired participants who were rated as CDR® sum of boxes (CDR®-SB) = 0. The CDR®-SB was not sensitive, particularly in participants with mild nonfluent/agrammatic primary progressive aphasia. Participants with familial and sporadic behavioral variant FTD exhibited similar CDR® plus NACC FTLD profiles except that language impairment was more frequent in participants with mild sporadic behavioral variant FTD. Adding the BEHAV and/or LANG domains to the CDR®-SB significantly enhanced discriminatory power in differentiating among the FTLD spectrum disorders. Discussion The BEHAV and LANG domains enable the CDR® plus NACC FTLD to capture early symptomatology of FTLD.

INTRODUCTION: We created global rating scoring rules for the CDR® plus NACC FTLD to detect and track early frontotemporal lobar degeneration (FTLD) and to conduct clinical trials in FTLD. METHODS: The CDR plus NACC FTLD rating was applied to 970 sporadic and familial participants from the baseline visit of Advancing Research and Treatment in Frontotemporal Lobar Degeneration (ARTFL)/Longitudinal Evaluation of Familial Frontotemporal Dementia Subjects (LEFFTDS). Each of the eight domains of the CDR plus NACC FTLD was equally weighed in determining the global score. An interrater reliability study was completed for 40 participants. RESULTS: The CDR plus NACC FTLD showed very good interrater reliability. It was especially useful in detecting clinical features of mild non‐fluent/agrammatic variant primary progressive aphasia participants. DISCUSSION: The global CDR plus NACC FTLD score could be an attractive outcome measure for clinical trials in symptomatic FTLD, and may be useful in natural history studies and clinical trials in FTLD spectrum disorders.

A variety of disease-modifying therapies for Alzheimer's disease (AD) have been developed and advanced to late-phase clinical trials in AD dementia patients, but thus far, no single drug has proven its efficacy in a large phase III trial. In 2011, the National Institute on Aging-Alzheimer's Association (NIA-AA) criteria redefined the concept of AD to encompass the earlier amyloid-related pathophysiological changes of the preclinical stage and mild cognitive impairment (MCI). Clinical trials for AD are now moving toward these earlier stages of the disease, targeting MCI due to AD and preclinical AD. Intervention in the earlier stages of the amyloid cascade is believed to have a better chance at changing the natural course of AD and preventing or at least delaying the conversion to dementia. Although conducting a large and prolonged costly clinical trial in the preclinical stage is challenging, the first step in overcoming this challenge has been taken with enthusiasm and commitment.

UTokyo Research掲載「細胞内の輸送の乱れがアルツハイマー病を引き起こす」 URI: http://www.u-tokyo.ac.jp/ja/utokyo-research/research-news/disruption-of-intracellular-transport-shown-to-trigger-alzheimers-disease.html, UTokyo Research "Disruption of intracellular transport shown to trigger Alzheimer’s disease" URI: http://www.u-tokyo.ac.jp/en/utokyo-research/research-news/disruption-of-intracellular-transport-shown-to-trigger-alzheimers-disease.html

Subjective memory complaints without objective cognitive impairments are common in elderly people. Recent evidence indicates subjective memory complaints is not merely a sign of a depressive state or an aging phenomenon, but an important risk factor for proceeding to mild cognitive impairment (MCI) and dementia in the future. Even when cognitively intact through the life, people with SMC tend to have more Alzheimer's disease (AD) pathology in the brain, which recently been defined as preclinical AD. Though not having the same clinical significance compared to MCI, we should keep in mind that elderly people with SMC are at risk for future cognitive decline and try to find out what specific biological backgrounds or clinical characters increase this cognitive risk.