Role of GBA variants in Lewy body disease neuropathology.

Rare and common GBA variants are risk factors for both Parkinson's disease (PD) and dementia with Lewy bodies (DLB). However, the degree to which GBA variants are associated with neuropathological features in Lewy body disease (LBD) is unknown. Herein, we assessed 943 LBD cases and examined associations of 15 different neuropathological outcomes with common and rare GBA variants. Neuropathological outcomes included LBD subtype, presence of a high likelihood of clinical DLB (per consensus guidelines), LB counts in five cortical regions, tyrosine hydroxylase immunoreactivity in the dorsolateral and ventromedial putamen, ventrolateral substantia nigra neuronal loss, Braak neurofibrillary tangle (NFT) stage, Thal amyloid phase, phospho-ubiquitin (pS65-Ub) level, TDP-43 pathology, and vascular disease. Sequencing of GBA exons revealed a total of 42 different variants (4 common [MAF > 0.5%], 38 rare [MAF < 0.5%]) in our series, and 165 cases (17.5%) had a copy of the minor allele for ≥ 1 variant. In analysis of common variants, p.L483P was associated with a lower Braak NFT stage (OR = 0.10, P < 0.001). In gene-burden analysis, presence of the minor allele for any GBA variant was associated with increased odds of a high likelihood of DLB (OR = 2.00, P < 0.001), a lower Braak NFT stage (OR = 0.48, P < 0.001), a lower Thal amyloid phase (OR = 0.55, P < 0.001), and a lower pS65-Ub level (ß: -0.37, P < 0.001). Subgroup analysis revealed that GBA variants were most common in LBD cases with a combination of transitional/diffuse LBD and Braak NFT stage 0-II or Thal amyloid phase 0-1, and correspondingly that the aforementioned associations of GBA gene-burden with a decreased Braak NFT stage and Thal amyloid phase were observed only in transitional or diffuse LBD cases. Our results indicate that in LBD, GBA variants occur most frequently in cases with greater LB pathology and low AD pathology, further informing disease-risk associations of GBA in PD, PD dementia, and DLB.

Lewy Body Disease is a Contributor to Logopenic Progressive Aphasia Phenotype.

OBJECTIVE: The objective of this study was to describe clinical features, [18 F]-fluorodeoxyglucose (FDG)-positron emission tomography (PET) metabolism and digital pathology in patients with logopenic progressive aphasia (LPA) and pathologic diagnosis of diffuse Lewy body disease (DLBD) and compare to patients with LPA with other pathologies, as well as patients with classical features of probable dementia with Lewy bodies (pDLB). METHODS: This is a clinicopathologic case-control study of 45 patients, including 20 prospectively recruited patients with LPA among whom 6 were diagnosed with LPA-DLBD. We analyzed clinical features and compared FDG-PET metabolism in LPA-DLBD to an independent group of patients with clinical pDLB and regional α-synuclein burden on digital pathology to a second independent group of autopsied patients with DLBD pathology and antemortem pDLB (DLB-DLBD). RESULTS: All patients with LPA-DLBD were men. Neurological, speech, and neuropsychological characteristics were similar across LPA-DLBD, LPA-Alzheimer's disease (LPA-AD), and LPA-frontotemporal lobar degeneration (LPA-FTLD). Genetic screening of AD, DLBD, and FTLD linked genes were negative with the exception of APOE ε4 allele present in 83% of LPA-DLBD patients. Seventy-five percent of the patients with LPA-DLBD showed a parietal-dominant pattern of hy pometabolism; LPA-FTLD - temporal-dominant pattern, whereas LPA-AD showed heterogeneous patterns of hypometabolism. LPA-DLBD had more asymmetrical hypometabolism affecting frontal lobes, with relatively spared occipital lobe in the nondominantly affected hemisphere, compared to pDLB. LPA-DLBD had minimal atrophy on gross brain examination, higher cortical Lewy body counts, and higher α-synuclein burden in the middle frontal and inferior parietal cortices compared to DLB-DLBD. INTERPRETATION: Whereas AD is the most frequent underlying pathology of LPA, DLBD can also be present and may contribute to the LPA phenotype possibly due to α-synuclein-associated functional impairment of the dominant parietal lobe. ANN NEUROL 2021;89:520-533.

Association of MAPT H1 subhaplotypes with neuropathology of lewy body disease.

BACKGROUND: Genetic variation at the microtubule-associated protein tau locus is associated with clinical parkinsonism. However, it is unclear as to whether microtubule-associated protein tau H1 subhaplotypes are associated with the burden of neuropathological features of Lewy body disease. OBJECTIVES: To evaluate associations of microtubule-associated protein tau haplotypes with severity of Lewy body pathology and markers of SN neuronal loss in Lewy body disease cases. METHODS: Five hundred eighty-five autopsy-confirmed Lewy body disease cases were included. Six microtubule-associated protein tau variants (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521) were genotyped to define common microtubule-associated protein tau haplotypes. Lewy body counts were measured in five cortical regions. Ventrolateral and medial SN neuronal loss were assessed semiquantitatively. Nigrostriatal dopaminergic degeneration was quantified by image analysis of tyrosine hydroxylase immunoreactivity in the dorsolateral and ventromedial putamen. RESULTS: The common microtubule-associated protein tau H2 haplotype did not show a strong effect on pathological burden in Lewy body disease. The rare H1j haplotype (1.3%) was significantly associated with a lower dorsolateral putaminal tyrosine hydroxylase immunoreactivity (and therefore greater dopaminergic degeneration) compared to other microtubule-associated protein tau haplotypes (P = 0.0016). Microtubule-associated protein tau H1j was also nominally (P ≤ 0.05) associated with a lower ventromedial putaminal tyrosine hydroxylase immunoreactivity (P = 0.010), but this did not survive multiple testing correction. Other nominally significant associations between microtubule-associated protein tau H1 subhaplotypes and neuropathological outcomes were observed. CONCLUSIONS: A rare microtubule-associated protein tau H1 subhaplotype (H1j) may be associated with more severe putaminal dopaminergic degeneration in Lewy body disease cases. Microtubule-associated protein tau H1j has been associated previously with an increased risk of PD, and therefore our exploratory findings provide insight into the mechanism by which H1j modulates PD risk. © 2019 International Parkinson and Movement Disorder Society.

123I-FP-CIT SPECT findings and its clinical relevance in prodromal dementia with Lewy bodies.

PURPOSE: Evidence for the prodromal stage of dementia with Lewy bodies (DLB) is very limited. To address this issue, we investigate the 123I-FP-CIT SPECT measure of dopamine transporter binding finding and its clinical relevance. METHODS: We enrolled subjects into a prodromal DLB group (PRD-DLB) (n = 20) and clinical DLB group (CLIN-DLB) (n = 18) and compared these groups with an Alzheimer's disease control group (AD) (n = 10). PRD-DLB was defined as patients having the non-motor symptoms associated with Lewy body disease (LBD) [i.e. REM sleep behavior disorder (RBD), olfactory dysfunction, autonomic dysfunction, and depression] and showing characteristic diffuse occipital hypometabolism in 18F-FDG PET. CLIN-DLB was defined as patients fulfilling the established criteria of probable DLB. Striatal specific binding ratio (SBR) of 123I-FP-CIT SPECT was used for objective group comparisons. The correlations between SBR and cognitive function (MMSE), motor symptoms (UPDRS3), and duration of LBD-associated non-motor symptoms were compared between the two DLB groups. RESULTS: Mean SBR scores of both PRD-DLB and CLIN-DLB were significantly lower than those of AD. No correlation was found between SBR and MMSE scores. Both in the CLIN-DLB and total DLB groups, SBR scores were negatively correlated with UPDRS3 scores, whereas no correlation was found in PRD-DLB. Among the LBD-related non-motor symptoms, duration of olfactory dysfunction, and RBD demonstrated negative correlation with SBR scores in PRD-DLB. CONCLUSION: 123I-FP-CIT SPECT may play a role for detecting DLB among the subjects in prodromal stage. During this stage, long-term olfactory dysfunction and/or RBD may indicate more severe degeneration of the nigro-striatal dopaminergic pathway.

Regional analysis and genetic association of nigrostriatal degeneration in Lewy body disease.

BACKGROUND: A number of genetic loci are associated with risk for Parkinson's disease (PD) based on genome-wide association studies; however, the relationship between genetic variants and nigrostriatal degeneration, which is the structural correlate of parkinsonism, has not been reported. OBJECTIVES: We quantified nigrostriatal dopaminergic integrity with image analysis of putaminal tyrosine hydroxylase immunoreactivity in 492 brains with Lewy body disease and used this pathologic endophenotype to explore possible association with PD genetic variants. METHODS: The study cases had Lewy-related pathology and variable degrees of nigrostriatal degeneration. They were assigned to one of the following clinical subgroups according to their predominant clinical syndrome: parkinsonism-predominant, parkinsonism+dementia, and dementia-predominant. In addition to putaminal tyrosine hydroxylase immunoreactivity, semiquantitative scoring was used to assess substantia nigra neuronal loss. A total of 29 PD genetic risk variants were genotyped on each case. RESULTS: When compared with controls, tyrosine hydroxylase immunoreactivity was reduced in Lewy body cases in the dorsolateral (79%) and ventromedial (57%) putamen. The dorsolateral region was better preserved in dementia-predominant cases than in cases with parkinsonism. Dorsolateral putaminal tyrosine hydroxylase immunoreactivity correlated with neuronal loss in the ventrolateral substantia nigra. Genetic analyses showed no significant association of PD risk variants with putaminal tyrosine hydroxylase immunoreactivity. CONCLUSIONS: The results confirm regional differences in putaminal dopaminergic degeneration and vulnerability of nigrostriatal pathway in Lewy body disorders with parkinsonism. The lack of association with PD genetic risk variants suggests that they may not be associated with quantitative endophenotypes of nigrostriatal degeneration, but more likely related to the risk of disease per se. © 2017 International Parkinson and Movement Disorder Society.

Cognitive impairment in progressive supranuclear palsy is associated with tau burden.

BACKGROUND: Cognitive impairment is one of the core features of progressive supranuclear palsy. This study aimed to clarify the profile of cognitive impairment and its underlying pathology in progressive supranuclear palsy. METHODS: We retrospectively reviewed medical records to evaluate the pattern and severity of cognitive impairment in 121 autopsy-confirmed progressive supranuclear palsy patients. A subset of 37 patients underwent neuropsychological evaluation as part of their clinical workup. The burden of progressive supranuclear palsy-related tau pathology (neurofibrillary tangles/pretangles, coiled bodies, tufted astrocytes, and threads) was semiquantitatively scored in 20 vulnerable brain regions. Concurrent pathologies potentially associated with cognitive impairment, such as Alzheimer's-type pathology, were also assessed. To evaluate possible genetic risk factors for cognitive impairment, genetic analysis for APOE and MAPT was performed. RESULTS: Ninety patients (74%) had documented cognitive impairment based on neurologic evaluation. In a subgroup with neuropsychological testing (n = 37), executive functioning was the most severely impaired cognitive domain. A global cognitive impairment index (Spearman's rho, -0.49; P = 0.005) and executive functioning were negatively correlated with total tau burden (Spearman's rho, -0.51; P = 0.003), but not correlated with the Alzheimer's-type pathology. APOE ɛ4 carriers had more severe amyloid pathology, but total tau burden and a global cognitive impairment index did not differ from APOE ɛ4 noncarriers. CONCLUSION: Cognitive impairment in progressive supranuclear palsy, most notably executive dysfunction, is associated with severity of progressive supranuclear palsy-related tau pathology. © 2017 International Parkinson and Movement Disorder Society.

Genetic association between RAGE polymorphisms and Alzheimer's disease and Lewy body dementias in a Japanese cohort: a case-control study.

BACKGROUND/AIMS: Interaction of receptor for advanced glycation end products (RAGE) with amyloid-ß increases amplification of oxidative stress and plays pathological roles in Alzheimer's disease (AD). Oxidative stress leads to α-synuclein aggregation and is also a major contributing factor in the pathogenesis of Lewy body dementias (LBDs). Therefore, we aimed to investigate whether RAGE gene polymorphisms were associated with AD and LBDs. METHODS: Four single nucleotide polymorphisms (SNPs)-rs1800624, rs1800625, rs184003, and rs2070600-of the gene were analyzed using a case-control study design comprising 288 AD patients, 76 LBDs patients, and 105 age-matched controls. RESULTS: Linkage disequilibrium (LD) examination showed strong LD from rs1800624 to rs2070600 on the gene (1.1 kb) in our cases in Japan. Rs184003 was associated with an increased risk of AD. Although there were no statistical associations for the other three SNPs, haplotypic analyses detected genetic associations between AD and the RAGE gene. Although relatively few cases were studied, results from the SNPs showed that they did not modify the risk of developing LBDs in the Japanese population. CONCLUSION: Our findings suggested that polymorphisms in the RAGE gene are involved in genetic susceptibility to AD. Copyright © 2016 John Wiley & Sons, Ltd.

Cognitive dysfunction in patients with very mild Alzheimer's disease and amnestic mild cognitive impairment showing hemispheric asymmetries of hypometabolism on ¹8F-FDG PET.

OBJECTIVE: We investigated cognitive dysfunction in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) who present hemispheric asymmetries of cerebral metabolic rate of glucose (CMRglc) decrease on (18) F-fluorodeoxyglucose positron emission tomography. METHODS: Based on the hemispheric asymmetries of CMRglc decrease in the posterior cingulate cortex, precuneus, and parietotemporal cortex, the patients were divided into three groups (a left-dominant hypometabolism group, a right-dominant hypometabolism group, and a non-dominant hypometabolism group). CMRglc decrease in the whole brain was controlled among the three groups. All the patients underwent mini-mental state examination (MMSE), Wechsler Memory Scale-Revised (WMS-R), and Wechsler Adult Intelligent Scale-Third (WAIS-III). RESULTS: There were no significant differences in MMSE and WAIS-III scores among the three groups. In WMS-R, the results indicated that the left-dominant group demonstrated significantly lower scores in verbal memory than the other two groups. Furthermore, the left-dominant group had a greater tendency to be diagnosed with AD rather than aMCI. CONCLUSIONS: Patients with AD and aMCI showing left-dominant hypometabolism tend to show severer impairment in verbal memory function and to be diagnosed with AD dementia.

Serum insulin-like growth factor-I and amyloid beta protein in Alzheimer's disease: relationship with cognitive function.

AIMS: Previous studies have suggested that insulin-like growth factor-I (IGF-I) deficiency may lead to cognitive deficits in neurodegenerative diseases such as Alzheimer's disease. The present study aimed to investigate the possible relationship between cognitive function and concentration of IGF-I or amyloid beta protein (Aß) in serum in Alzheimer's patients. METHODS: A total of 81 Japanese patients were enrolled in this study. Concentrations of IGF-I, Aß42, and Aß40 in serum were measured. Two neuropsychological tests, Mini-Mental State Examination and Hasegawa's Dementia Scale-Revised (HDS-R), were also performed. Linear correlations among the age, serum IGF-I, serum Aß42 or Aß40, Aß42/Aß40 ratio, Mini-Mental State Examination or HDS-R total score, and the scores for six HDS-R subscales were analyzed by regression analysis. RESULTS: IGF-I showed a significant negative correlation with age (ß = -0.357, P = 0.002) and a positive correlation with Aß42/Aß40 ratio (ß = 0.318, P = 0.007). Serum IGF-I and both the Mini-Mental State Examination and the HDS-R total score also correlated (ß = 0.505, ß = 0.524, P < 0.01). Among the HDS-R subscales, 'Recall' (ρ = 0.379, P < 0.01), 'Verbal fluency' (ρ = 0.360, P < 0.01), and 'Attention and calculation' (ρ = 0.389, P < 0.01) showed significant positive correlations with serum IGF-I. CONCLUSION: The results, specifically that lower serum IGF-I was associated with cognitive impairment, suggest that metabolism of IGF-I may be involved in the pathogenesis of cognitive deficits in Alzheimer's disease.

Clinical profiles of dementia with Lewy bodies with and without Alzheimer's disease-like hypometabolism.

OBJECTIVES: It is well known that Alzheimer's disease (AD)-type pathology is commonly present in dementia with Lewy bodies (DLB) brains and that the degree of AD-type pathology has an influence on the clinical characteristics of DLB. Although significant hypometabolism in the temporoparietal/precuneus on [(18)F]fluoro-d-glucose ((18)F-FDG) positron emission tomography (PET) scans is considered to support a diagnosis of AD, some DLB patients also exhibit this metabolic pattern. The clinical significance of the metabolic pattern on DLB remains unknown. METHODS: Twenty-three DLB patients, 10 AD patients, and 11 controls underwent (18)F-FDG PET scans. According to the degree of hypometabolism in the parietal/precuneus regions, representing the AD-like metabolic pattern, 12 patients were placed in the DLB-AD(+) group and 11 patients were placed in the DLB-AD(-) group. The demographics and clinical variables were compared among the four groups. RESULTS: In addition to the parietal/precuneus regions, the DLB-AD(+) group exhibited significantly greater posterior cingulate hypometabolism than the DLB-AD(-) group, although occipital metabolism did not differ. The prevalence of visual hallucinations and extracampine hallucinations, and the Bender-Gestalt test score were significantly higher in the DLB-AD(+) group than the DLB-AD(-) group, although there were no differences in the demographics and other examined clinical variables between the two DLB groups. These clinical differences were absent in the DLB-AD(-) group, AD group, and controls. CONCLUSIONS: Parietal/precuneus hypometabolism may be associated with clinical characteristics in DLB patients. Further multiple imaging modalities that are sensitive to AD-type pathology are needed to reveal the neurobiological basis of the AD-like metabolic pattern.

Association between the catechol-O-methyltransferase polymorphism Val158Met and Alzheimer's disease in a Japanese population.

OBJECTIVE: Catechol-O-methyltransferase (COMT) plays an important role in dopamine degradation, which is associated with the pathophysiology of Alzheimer's disease (AD) and alcoholism. A functional COMT polymorphism, Val158Met (rs4680 G > A), affects the onset of AD and is associated with alcohol dependence through dopamine receptor sensitivity in the prefrontal cortex. METHODS: The aim of this case-control study (398 cases and 149 controls) was to investigate whether Val158Met polymorphism influences the onset of AD stratified according to alcohol consumption and apolipoprotein E (APOE) status. We also used single photon-emission computed tomography (SPECT) to analyse 26 patients with AD with the polymorphism. RESULTS: As a function of APOE status, the genotypic frequencies of rs4680 in patients with AD did not differ from those in controls. We detected a significant association between high alcohol consumption in patients with AD (HAC-AD group) and the polymorphism in genotypic and allelic frequencies. Logistic regression analyses demonstrated that the presence of the APOE genotype with rs4680 increased the risk for HAC-AD synergistically. Hyperperfusion in the right sub-lobar insula of patients with the G/G genotype was found compared with that of patients with the G/A genotype. SPECT studies showed a relationship between the polymorphism and compensatory reactions for dysfunctions of dopaminergic neurotransmission in AD pathophysiology. CONCLUSION: Although genetic association between the polymorphism and the onset of AD in a Japanese population were not observed, the polymorphism affected the risk for HAC-AD.

An autopsied case of corticobasal degeneration showing severe cerebral atrophy over a protracted disease course of 16 years.

The patient was a 72-year-old Japanese woman. At the age of 57, she started having difficulty performing daily work and developed agraphia. She also exhibited restlessness and loss of interest, and began to speak less. Thereafter, stereotypical behavior, gait disturbance and dysphagia were noted. CT scan demonstrated left-dominant frontal and temporal lobe atrophy. She died at the age of 72, about 16 years after the onset of symptoms. Neuropathologically, the brain weighed 867 g, and showed remarkable cerebral atrophy with degeneration of the white matter, predominantly in the left dorsal frontal lobe and anterior temporal lobe. Microscopically, severe neuronal loss and gliosis with rarefaction were found in the cerebral cortex, and severe destruction of myelin and axons was observed in the cerebral white matter. Moderate neuronal loss with gliosis was also found in the pallidum and substantia nigra. Gallyas-Braak staining and tau immunostaining revealed pretangle neurons, NFTs, ballooned neurons and astrocytic plaques in the cerebral cortex, subcortical nuclei and brainstem, and argyrophilic threads and coiled bodies in the subcortical white matter. Tau isoform-specific immunostaining revealed that most tau-immunoreactive structures were positive for 4-repeat (4R) tau, but some of the NFTs were positive for 3-repeat (3R) tau in the cerebral neocortex. Immunoblotting demonstrated an accumulation of 4R tau in the cerebral cortex and subcortical white matter. The patient was pathologically diagnosed as having corticobasal degeneration. Her long survival course likely accounts for the severe white matter degeneration and accumulation of 3R tau in NFTs.

Primary visual cortical metabolism and rapid eye movement sleep behavior disorder in dementia with Lewy bodies.

AIM: Significant glucose hypometabolism in the primary visual cortex (PVC) is considered to support a diagnosis of dementia with Lewy bodies (DLB), but its relationship to the clinical features remains unknown. The purpose of this study was to assess the association between the metabolic pattern and clinical variables in DLB. METHODS: A total of 27 DLB patients who underwent [18F]fluoro-d-glucose (18F-FDG) positron emission tomography scans were examined. Demographics and clinical variables were compared between patients with and without glucose hypometabolism in the PVC. The correlations between the cerebral metabolic rate of glucose in the PVC and clinical variables were also investigated. RESULTS: Only the onset age of probable rapid eye movement sleep behavior disorder (RBD) was significantly different between patients with and withoutglucose hypometabolism in the PVC, being younger in patients with the metabolic pattern; there were no other differences in clinical variables. The onset age of probable RBD was significantly correlated with the cerebral metabolic rate of glucose in the PVC. CONCLUSIONS: Glucose hypometabolism in the PVC provides a potential mechanism for the link between antecedent RBD and the subsequent development of dementia in DLB patients. Glucose hypometabolism in the PVC may represent the effect of the pathophysiological process of DLB on RBD rather than a distinct condition in the disease progression. The physiological aspects of the link between this metabolic pattern and the onset of RBD remain unclear.

Three presenile patients in which neuropsychological and neuroimaging examinations suggest possible progression to dementia with Lewy bodies.

We report three presenile patients who were initially suspected of having Alzheimer's disease (AD) or being in the prodromal stage of AD, regardless of visuoperceptual dysfunctions in daily living, because they lacked the core features and prodromal non-motor symptoms of dementia with Lewy bodies. Subsequently, progression to dementia with Lewy bodies was suspected based on neuropsychological and neuroimaging findings; additionally, one of the three patients suffered from visual hallucinations. Neuropsychological examinations such as subjective contours, cube copying and block design in the Wechsler Adult Intelligence Scale-III revealed visuoperceptual dysfunction in all three patients even when other cognitive functions were rather preserved. Brain magnetic resonance imaging revealed no significant brain atrophy, including in the parieto-occipital area and the hippocampus, while brain (18)F-fluorodeoxyglucose positron emission tomography demonstrated right dominant metabolic reductions in the occipital lobe, including the primary visual cortex, in all three patients. We suggest the possibility of progression to dementia with Lewy bodies, but not AD or posterior cortical atrophy. Regardless of the presence of core features and prodromal non-motor symptoms, this progression is suggested when there are difficulties only in higher-level visual processing such as subjective contours and block design in the Wechsler Adult Intelligence Scale-III, no significant atrophy of the parieto-occipital area and hippocampus on brain magnetic resonance imaging, and hypometabolism in the occipital lobe including the primary visual cortex on brain (18)F-fluorodeoxyglucose positron emission tomography.

Levodopa treatment and mood fluctuation in dementia with Lewy bodies: a case report.

L-3,4-dihydroxyphenylalanine (L-dopa) has been the gold standard for pharmacotherapy for parkinsonism in patients with dementia with Lewy bodies (DLB). While L-dopa treatment is related to visual hallucinations, its relationship to mood fluctuation in DLB is poorly understood. Herein, we report the improvement of behavioural and psychological symptoms of dementia through the adjustment of L-dopa treatment in a 78-year-old woman with probable DLB. Her marked mood swings were improved by changing L-dopa administration from three to five times per day while maintaining the same total daily dosage. This observation suggests that there may be an association between plasmatic L-dopa levels and mood fluctuation in patients with DLB. This pharmacological approach may be useful in the management of behavioural and psychological symptoms of dementia without the use of antipsychotic agents to avoid severe neuroleptic sensitivity, which is one of the suggestive clinical features in the Third Consortium on DLB clinical criteria.

Intelligence or years of education: which is better correlated with memory function in normal elderly Japanese subjects?

BACKGROUND: We compared differences in intelligence and memory function between normal elderly Japanese subjects with more years of education and those with fewer years of education. We also investigated clinical and neuropsychological factors that are strongly correlated with memory function. METHODS: There were 118 normal elderly subjects who underwent the Mini-Mental State Examination, Wechsler Adult Intelligence Scale, 3rd edition (WAIS-III), and Wechsler Memory Scale Revised. Subjects with at least 13 years of education were categorized as the H group, and those with 12 years of education or less were categorized as the L group. RESULTS: Age and Mini-Mental State Examination scores were not significantly different between the two groups. On the WAIS-III, there were significant differences between the two groups in Verbal IQ and Full Scale IQ. On the Wechsler Memory Scale Revised, there were significant differences between the two groups in Visual Memory, General Memory, and Delayed Recall. Correlation coefficients between memory function and the other factors demonstrated significant but weak correlations between years of education and General Memory (R = 0.22) and between years of education and Delayed Recall (R = 0.20). Strong correlations were found between Verbal IQ and Verbal Memory (R = 0.45), between Verbal IQ and General Memory (R = 0.49), between Full Scale IQ and General Memory (R = 0.50) and between Full Scale IQ and Delayed Recall (R = 0.48). CONCLUSIONS: In normal elderly Japanese subjects, years of education weakly correlated with memory function while Verbal IQ, Full Scale IQ and Verbal Comprehension on WAIS-III had stronger correlations with memory function. Verbal IQ and Verbal Comprehension on WAIS-III were found to be insusceptible to the cognitive decline characteristic of Alzheimer's disease or amnestic mild cognitive impairment. Therefore, verbal intelligence, as measured by Verbal IQ and Verbal Comprehension, may be the most useful factor for inferring premorbid memory function in Alzheimer's disease or amnestic mild cognitive impairment patients.

Dementia with Lewy bodies: early diagnostic challenges.

Dementia with Lewy bodies (DLB) is defined pathologically as neurodegeneration associated with Lewy bodies (LB). LB-related symptoms, including olfactory dysfunction, dysautonomia, and mood and sleep disorders, are increasingly recognized as clinical signs that enable the early detection of DLB, because these symptoms often antedate dementia by years or even decades. It remains unknown if the clinical history of LB-related symptoms is sufficient for the prodromal state of DLB to be suspected in memory clinics. We retrospectively investigated the clinical courses, including olfactory dysfunction, dysautonomia, depression, and rapid eye movement sleep behaviour disorder, of 90 patients with probable DLB. The timing of LB-related symptoms that preceded or followed relative to the onset of memory loss was calculated. LB-related symptoms were present in 79 of 90 patients (87.8%) with probable DLB before or at the time of memory loss onset. These symptoms preceded the onset of memory loss between 1.2 and 9.3 years. We also report on four non-demented patients with a clinical history of LB-related symptoms in our memory clinic. All four patients showed reduced cardiac [(123) I]-metaiodobenzylguanidine levels. Moreover, [(18) F]fluoro-D-glucose positron emission tomography scans revealed glucose hypometabolism in the occipital cortex in two patients. One patient converted to probable DLB with the development of parkinsonism 2 years after major depression was diagnosed. Based on a clinical history of LB-related symptoms, we propose a conceptual framework to identify these symptomatic but non-demented individuals that led us to suspect the underlying pathophysiology of Lewy body disease. Further prospective study is warranted to determine the clinical significance of LB-related symptoms in non-demented patients.

Retrospective survey of prodromal symptoms in dementia with Lewy bodies: comparison with Alzheimer's disease.

BACKGROUND: Non-motor symptoms are recognized to enable the early detection of Parkinson's disease (PD). It remains unknown when those symptoms appear in dementia with Lewy bodies (DLB). METHOD: We investigated the prevalence of 15 non-motor symptoms of PD at the onset of memory loss based on a standardized worksheet in 34 patients with DLB, 32 patients with Alzheimer's disease (AD) and 30 normal controls. RESULTS: DLB patients exhibited a significantly higher prevalence of olfactory dysfunction, constipation, increased saliva and signs of rapid eye movement sleep behavior disorder at the onset of memory loss than AD patients and normal controls. CONCLUSIONS: Paying attention to non-motor symptoms of PD may help DLB diagnosis in the early stage, especially in terms of its differentiation from AD.