ABSTRACT
BACKGROUND: Previous research studies have demonstrated abnormalities in the metabolism of mothers of young children with autism. METHODS: Metabolic analysis was performed on blood samples from 30 mothers of young children with Autism Spectrum Disorder (ASD-M) and from 29 mothers of young typically-developing children (TD-M). Targeted metabolic analysis focusing on the folate one-carbon metabolism (FOCM) and the transsulfuration pathway (TS) as well as broad metabolic analysis were performed. Statistical analysis of the data involved both univariate and multivariate statistical methods. RESULTS: Univariate analysis revealed significant differences in 5 metabolites from the folate one-carbon metabolism and the transsulfuration pathway and differences in an additional 48 metabolites identified by broad metabolic analysis, including lower levels of many carnitine-conjugated molecules. Multivariate analysis with leave-one-out cross-validation allowed classification of samples as belonging to one of the two groups of mothers with 93% sensitivity and 97% specificity with five metabolites. Furthermore, each of these five metabolites correlated with 8-15 other metabolites indicating that there are five clusters of correlated metabolites. In fact, all but 5 of the 50 metabolites with the highest area under the receiver operating characteristic curve were associated with the five identified groups. Many of the abnormalities appear linked to low levels of folate, vitamin B12, and carnitine-conjugated molecules. CONCLUSIONS: Mothers of children with ASD have many significantly different metabolite levels compared to mothers of typically developing children at 2-5 years after birth.
Subject(s)
Autism Spectrum Disorder , Biomarkers , Case-Control Studies , Child , Child, Preschool , Female , Folic Acid , Humans , MothersABSTRACT
INTRODUCTION: Some Alzheimer's disease biomarker studies found amyloid changes 20 years or more in advance of expected symptoms, while cognitive changes lagged for more than a decade, but this apparent lag might reflect the sensitivities of the biomarker and cognitive assays used. How far in advance of incident amnestic mild cognitive impairment (MCI) does cognition begin to decline? METHODS: Longitudinal neuropsychological study of an apolipoprotein E e4 enriched cohort of cognitively normal individuals at entry. Linear mixed models for MCI converters (n = 65) and nonconverters (n = 719) fitted for each neuropsychological measure; annual changes compared between groups before and after linear model intersections (inflection points). RESULTS: 34 of 35 cognitive measures and 9 of 18 behavioral measures declined faster post-inflection in the MCI converters; the earliest cognitive inflection point was nearly 20 years in advance of MCI diagnosis. DISCUSSION: The preclinical duration of cognitive and behavioral changes approaches the earliest reported biomarker changes.
Subject(s)
Apolipoprotein E4/genetics , Cognitive Dysfunction , Disease Progression , Neuropsychological Tests/statistics & numerical data , Prodromal Symptoms , Aged , Biomarkers , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/genetics , Cohort Studies , Female , Humans , Longitudinal Studies , MaleABSTRACT
Frontotemporal lobar degeneration with neuronal inclusions of the TAR DNA-binding protein 43 (FTLD-TDP) represents the most common pathological subtype of FTLD. We established the international FTLD-TDP whole-genome sequencing consortium to thoroughly characterize the known genetic causes of FTLD-TDP and identify novel genetic risk factors. Through the study of 1131 unrelated Caucasian patients, we estimated that C9orf72 repeat expansions and GRN loss-of-function mutations account for 25.5% and 13.9% of FTLD-TDP patients, respectively. Mutations in TBK1 (1.5%) and other known FTLD genes (1.4%) were rare, and the disease in 57.7% of FTLD-TDP patients was unexplained by the known FTLD genes. To unravel the contribution of common genetic factors to the FTLD-TDP etiology in these patients, we conducted a two-stage association study comprising the analysis of whole-genome sequencing data from 517 FTLD-TDP patients and 838 controls, followed by targeted genotyping of the most associated genomic loci in 119 additional FTLD-TDP patients and 1653 controls. We identified three genome-wide significant FTLD-TDP risk loci: one new locus at chromosome 7q36 within the DPP6 gene led by rs118113626 (p value = 4.82e - 08, OR = 2.12), and two known loci: UNC13A, led by rs1297319 (p value = 1.27e - 08, OR = 1.50) and HLA-DQA2 led by rs17219281 (p value = 3.22e - 08, OR = 1.98). While HLA represents a locus previously implicated in clinical FTLD and related neurodegenerative disorders, the association signal in our study is independent from previously reported associations. Through inspection of our whole-genome sequence data for genes with an excess of rare loss-of-function variants in FTLD-TDP patients (n ≥ 3) as compared to controls (n = 0), we further discovered a possible role for genes functioning within the TBK1-related immune pathway (e.g., DHX58, TRIM21, IRF7) in the genetic etiology of FTLD-TDP. Together, our study based on the largest cohort of unrelated FTLD-TDP patients assembled to date provides a comprehensive view of the genetic landscape of FTLD-TDP, nominates novel FTLD-TDP risk loci, and strongly implicates the immune pathway in FTLD-TDP pathogenesis.
Subject(s)
Nerve Tissue Proteins/genetics , TDP-43 Proteinopathies/genetics , Aged , DNA Repeat Expansion , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/genetics , Female , Frontal Lobe/metabolism , Frontotemporal Lobar Degeneration/genetics , Frontotemporal Lobar Degeneration/immunology , Genetic Predisposition to Disease , Genome-Wide Association Study , HLA-DQ Antigens/genetics , Humans , Intracellular Signaling Peptides and Proteins , Loss of Function Mutation , Male , Middle Aged , Nerve Tissue Proteins/physiology , Potassium Channels/genetics , Progranulins/genetics , Progranulins/physiology , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/physiology , Proteins/genetics , Proteins/physiology , RNA, Messenger/biosynthesis , Risk Factors , Sequence Analysis, RNA , Societies, Scientific , TDP-43 Proteinopathies/immunology , White People/geneticsABSTRACT
INTRODUCTION: Roughly 4% to 23% of the population embody stress prone personality and other traits characterizing a subclinical "broad autism phenotype" (BAP). Subjective cognitive impairment (SCI) among healthy elderly is associated with psychological distress leading us to predict BAP would be associated with SCI. METHODS: The Autism Spectrum Quotient, a self-administered 50 item questionnaire, was completed by 419 consecutive members of the Arizona APOE Cohort who underwent neuropsychological testing every 2 years. SCI was assessed with self and informant versions of the Multidimensional Assessment of Neurodegenerative Symptoms (MANS) Questionnaire. RESULTS: A total of 45 individuals scored in the BAP range, designated BAP+, and the rest were BAP-. At entry, both Multidimensional Assessment of Neurodegenerative Symptoms Questionnaire Self and Informant scores were higher in the BAP+ group (P<0.0001). After age 60, the BAP+ group had greater annual increases in Multidimensional Assessment of Neurodegenerative Symptoms Questionnaire Self scores (0.05 vs. 0.02; difference=0.03; 95% confidence interval, 0.004-0.05; P=0.02) yet there was no difference between groups in memory decline. Over ~10 years 33 individuals developed mild cognitive impairment: 4 in the BAP+ group (8.9%) and 29 in the BAP- group (7.8%), P=0.77. DISCUSSION: Individuals who meet criteria for the BAP have escalating SCI with age, but no greater rate of memory decline or clinical progression to mild cognitive impairment.
Subject(s)
Autistic Disorder/psychology , Cognitive Dysfunction/diagnosis , Phenotype , Self Report , Aged , Apolipoproteins E , Cognitive Dysfunction/genetics , Female , Humans , Longitudinal Studies , Male , Neuropsychological Tests/statistics & numerical data , Surveys and QuestionnairesABSTRACT
OBJECTIVES: The aim of this study was to assess the association between personality factors and age-related longitudinal cognitive performance, and explore interactions of stress-proneness with apolipoprotein E (APOE) É4, a prevalent risk factor for Alzheimer's disease (AD). METHODS: A total of 510 neuropsychiatrically healthy residents of Maricopa County recruited through media ads (mean age 57.6±10.6 years; 70% women; mean education 15.8±2.4 years; 213 APOE É4 carriers) had neuropsychological testing every 2 years (mean duration follow-up 9.1±4.4 years), and the complete Neuroticism Extraversion Openness Personality Inventory-Revised. Several tests were administered within each of the following cognitive domains: memory, executive skills, language, visuospatial skills, and general cognition. Primary effects on cognitive trajectories and APOE É4 interactions were ascertained with quadratic models. RESULTS: With personality factors treated as continuous variables, Neuroticism was associated with greater decline, and Conscientiousness associated with reduced decline consistently across tests in memory and executive domains. With personality factors trichotomized, the associations of Neuroticism and Conscientiousness were again highly consistent across tests within memory and to a lesser degree executive domains. While age-related memory decline was greater in APOE É4 carriers as a group than É4 noncarriers, verbal memory decline was mitigated in É4 carriers with higher Conscientiousness, and visuospatial perception and memory decline was mitigated in É4 carriers with higher Openness. CONCLUSIONS: Neuroticism and Conscientiousness were associated with changes in longitudinal performances on tests sensitive to memory and executive skills. APOE interactions were less consistent. Our findings are consistent with previous studies that have suggested that personality factors, particularly Neuroticism and Conscientiousness are associated with cognitive aging patterns. (JINS, 2016, 22, 765-776).
Subject(s)
Cognitive Aging/physiology , Conscience , Executive Function/physiology , Memory/physiology , Neuroticism/physiology , Personality/physiology , Aged , Apolipoprotein E4/genetics , Female , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
Studies have demonstrated associations between cardiovascular factors and Alzheimer disease (AD) with minimal focus on other neurodegenerative diseases. Utilizing cross-sectional data from 17,532 individuals in the National Alzheimer's Coordinating Center, Uniform Data Set, we compared the presence of cardiovascular factors [body mass index (BMI), atrial fibrillation, hypertension, hyperlipidemia, and diabetes] in individuals carrying a diagnosis of Probable AD (ProbAD), Possible AD, vascular dementia, dementia with Lewy bodies (DLB), frontotemporal dementia, Parkinson disease, progressive supranuclear palsy, or corticobasal degeneration, with that of normals. Generalized linear mixed models were fitted with age at visit, gender, and cardiovascular factors as fixed effects and Alzheimer's Disease Centers as random effects. In late life, only BMI of ProbAD and DLB patients was statistically significantly lower than that in normals (P-values <0.001). When accounting for colinearity within cardiovascular factors, a low BMI was a comorbidity of certain dementia etiologies as compared with normals. These data support a concept of disease-specific associations with certain cardiovascular factors.
Subject(s)
Body Mass Index , Hypertension , Neurodegenerative Diseases/complications , Aged , Atrial Fibrillation , Cross-Sectional Studies , Databases, Factual , Diabetes Mellitus , Female , Humans , Male , Middle Aged , Neuropsychological Tests , Risk FactorsABSTRACT
Education and related proxies for cognitive reserve (CR) are confounded by associations with environmental factors that correlate with cerebrovascular disease possibly explaining discrepancies between studies examining their relationships to cognitive aging and dementia. In contrast, sex-related memory differences may be a better proxy. Since they arise developmentally, they are less likely to reflect environmental confounds. Women outperform men on verbal and men generally outperform women on visuospatial memory tasks. Furthermore, memory declines during the preclinical stage of AD, when it is clinically indistinguishable from normal aging. To determine whether CR mitigates age-related memory decline, we examined the effects of gender and APOE genotype on longitudinal memory performances. Memory decline was assessed in a cohort of healthy men and women enriched for APOE É4 who completed two verbal [Rey Auditory Verbal Learning Test (AVLT), Buschke Selective Reminding Test (SRT)] and two visuospatial [Rey-Osterrieth Complex Figure Test (CFT), and Benton Visual Retention Test (VRT)] memory tests, as well as in a separate larger and older cohort [National Alzheimer's Coordinating Center (NACC)] who completed a verbal memory test (Logical Memory). Age-related memory decline was accelerated in APOE É4 carriers on all verbal memory measures (AVLT, p=.03; SRT p<.001; logical memory p<.001) and on the VRT p=.006. Baseline sex associated differences were retained over time, but no sex differences in rate of decline were found for any measure in either cohort. Sex-based memory advantage does not mitigate age-related memory decline in either APOE É4 carriers or non-carriers.
Subject(s)
Aging , Cognition Disorders/physiopathology , Cognitive Reserve/physiology , Memory Disorders/physiopathology , Sex Characteristics , Age Factors , Aged , Aged, 80 and over , Apolipoproteins E/genetics , Cognition Disorders/genetics , Cohort Studies , Female , Humans , Male , Memory Disorders/genetics , Middle Aged , Neuropsychological Tests , Verbal Learning/physiologyABSTRACT
The authors compared the risk for subjective cognitive impairment (SCI) between carriers of the apolipoprotein E ε4 (APOE ε4) allele (cases) and APOE ε4 noncarriers (controls). SCI was assessed by a validated self-reported questionnaire. The authors used multivariable logistic regression analyses to compute odds ratios and 95% confidence intervals adjusted for age, sex, education, and marital status. Data were available on 114 participants (83 women; 47 APOE ε4 carriers; mean age, 69 years). The risk for SCI was significantly higher among cases than controls, particularly for those 70 years of age and older. These findings should be considered preliminary until confirmed by a prospective cohort study.
Subject(s)
Aging/psychology , Apolipoproteins E/genetics , Cognition Disorders/genetics , Genetic Predisposition to Disease , Adult , Aged , Aged, 80 and over , Alleles , Female , Genotype , Humans , Male , Middle Aged , Neuropsychological Tests , Young AdultABSTRACT
The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain-only donations and currently has banked more than 1600 brains. More than 430 whole-body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0-hour median post-mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant-funded projects.
Subject(s)
Aging/pathology , Brain/pathology , Neurodegenerative Diseases/pathology , Tissue Banks , Tissue and Organ Procurement , Aged, 80 and over , Arizona , Autopsy , Biomarkers , Female , Humans , Male , Organ Preservation , Postmortem Changes , Tissue Donors , Tissue SurvivalABSTRACT
OBJECTIVE: A National Institute on Aging-sponsored work group on preclinical Alzheimer's disease (AD) articulated the need to characterize cognitive differences between normal aging and preclinical AD. METHODS: Seventy-one apolipoprotein E (APOE) ε4 homozygotes, 194 ε3/ε4 heterozygotes, and 356 ε4 noncarriers age 21 to 87 years who were cognitively healthy underwent neuropsychological testing every 2 years. Longitudinal trajectories of test scores were compared between APOE subgroups. RESULTS: There was a significant effect of age on all cognitive domains in both APOE ε4 carriers and noncarriers. A significant effect of APOE ε4 gene dose was confined to the memory domain and the Dementia Rating Scale. Cross-sectional comparisons did not discriminate the groups. CONCLUSIONS: Although cognitive aging patterns are similar in APOE ε4 carriers and noncarriers, preclinical AD is characterized by a significant ε4 gene dose effect that impacts memory and is detectable longitudinally. Preclinical neuropsychological testing strategies should emphasize memory-sensitive measures and longitudinal design.
Subject(s)
Aging , Alzheimer Disease/complications , Alzheimer Disease/psychology , Cognition Disorders/etiology , Adult , Aged , Aged, 80 and over , Alzheimer Disease/genetics , Apolipoprotein E4/genetics , Executive Function , Female , Humans , Language , Longitudinal Studies , Male , Middle Aged , Neuropsychological Tests , Visual Perception , Young AdultABSTRACT
BACKGROUND: The G2019S leucine-rich repeat kinase 2 (LRRK2) gene mutation is an important and commonly found genetic determinant of Parkinson's disease (PD). The neuropathological findings associated with this mutation have thus far been varied but are most often associated with Lewy body (LB) pathology. OBJECTIVE: Describe a case of clinical Parkinson's disease with levodopa responsiveness found to have LRRK2 mutations and the absence of Lewy bodies. METHOD: We present an 89-year-old man with a 10-year history of slowly progressive parkinsonism suspected to be secondary to Parkinson's disease. RESULTS: Neuropathological evaluation revealed nigral degeneration without Lewy bodies or Lewy neurites, but there were frequent tau-immunopositive neurites and astrocytes in the putamen and substantia nigra, neocortical glial tau positive astrocytes associated with aging-related tau astrogliopathy (ARTAG), as well as neurofibrillary tangles, beta amyloid plaques, and amyloid angiopathy typical of advanced Alzheimer's disease. G2019S LRRK2 homozygous mutations were found. CONCLUSION: This case illustrates that levodopa-responsive clinical PD caused by G2019S LRRK2 mutations can occur without Lewy bodies.
Subject(s)
Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 , Lewy Bodies , Mutation , Parkinson Disease , Protein Serine-Threonine Kinases , Humans , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Male , Parkinson Disease/genetics , Parkinson Disease/pathology , Aged, 80 and over , Lewy Bodies/pathology , Lewy Bodies/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , tau Proteins/genetics , tau Proteins/metabolism , Levodopa/therapeutic useABSTRACT
OBJECTIVE: To evaluate the performance of Alzheimer disease (AD) cerebrospinal fluid (CSF) biomarkers in a tertiary neurology clinic setting with high frequency of non-AD cases, including normal pressure hydrocephalus (NPH). METHODS: There were 534 patients who underwent AD CSF biomarkers (Roche Elecsys Aß42, p-Tau181, total-Tau) from April 1, 2020, through April 23, 2021. A behavioral neurologist blinded to CSF results assigned a clinical diagnosis retrospectively on the basis of consensus criteria, and a neuroradiologist blinded to the diagnosis and CSF studies graded brain magnetic resonance images for indicators of CSF dynamics disorders. Associations between biomarkers, diagnoses, and imaging were assessed by χ2, analysis of covariance, and linear regression methods. RESULTS: Median age at time of testing was 67 years (range, 19 to 96 years), median symptom duration was 2 years (range, 0.4 to 28 years), and median Short Test of Mental Status score was 30 (range, 0 to 38). Clinical diagnoses significantly correlated with different CSF biomarker values (χ2=208.3; P=10e-4). p-Tau181/Aß42 ratios above 0.023 positively correlated with Alzheimer dementia (more than individual measures). This ratio also had the best performance for differentiating Alzheimer dementia from NPH (area under the curve, 0.869). Imaging markers supportive of CSF dynamics disorders correlated with low Aß42, p-Tau181, and total-Tau. CONCLUSION: In a heterogeneous clinical population, abnormal p-Tau181/Aß42 ratios (>0.023) have the strongest association with Alzheimer dementia and probably represent a comorbid AD pathologic component in persons clearly matching non-AD neurodegenerative syndromes. Altered CSF dynamics were associated with lower concentrations of AD CSF biomarkers regardless of clinical diagnosis, but the ratio compensates for these changes. In the appropriate clinical setting, an isolated abnormal Aß42 should prompt consideration of NPH.
Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Biomarkers , tau Proteins , Humans , Alzheimer Disease/cerebrospinal fluid , Alzheimer Disease/diagnosis , Biomarkers/cerebrospinal fluid , Aged , Male , Female , Middle Aged , Amyloid beta-Peptides/cerebrospinal fluid , tau Proteins/cerebrospinal fluid , Aged, 80 and over , Adult , Retrospective Studies , Peptide Fragments/cerebrospinal fluid , Hydrocephalus, Normal Pressure/cerebrospinal fluid , Hydrocephalus, Normal Pressure/diagnosis , Tertiary Care Centers , Young Adult , Magnetic Resonance Imaging/methodsABSTRACT
Expanded glutamine repeats of the ataxin-2 (ATXN2) protein cause spinocerebellar ataxia type 2 (SCA2), a rare neurodegenerative disorder. More recent studies have suggested that expanded ATXN2 repeats are a genetic risk factor for amyotrophic lateral sclerosis (ALS) via an RNA-dependent interaction with TDP-43. Given the phenotypic diversity observed in SCA2 patients, we set out to determine the polymorphic nature of the ATXN2 repeat length across a spectrum of neurodegenerative disorders. In this study, we genotyped the ATXN2 repeat in 3919 neurodegenerative disease patients and 4877 healthy controls and performed logistic regression analysis to determine the association of repeat length with the risk of disease. We confirmed the presence of a significantly higher number of expanded ATXN2 repeat carriers in ALS patients compared with healthy controls (OR = 5.57; P= 0.001; repeat length >30 units). Furthermore, we observed significant association of expanded ATXN2 repeats with the development of progressive supranuclear palsy (OR = 5.83; P= 0.004; repeat length >30 units). Although expanded repeat carriers were also identified in frontotemporal lobar degeneration, Alzheimer's and Parkinson's disease patients, these were not significantly more frequent than in controls. Of note, our study identified a number of healthy control individuals who harbor expanded repeat alleles (31-33 units), which suggests caution should be taken when attributing specific disease phenotypes to these repeat lengths. In conclusion, our findings confirm the role of ATXN2 as an important risk factor for ALS and support the hypothesis that expanded ATXN2 repeats may predispose to other neurodegenerative diseases, including progressive supranuclear palsy.
Subject(s)
Nerve Degeneration/genetics , Nerve Tissue Proteins/genetics , Repetitive Sequences, Nucleic Acid/genetics , Adult , Aged , Aged, 80 and over , Ataxins , Cohort Studies , Demography , Female , Humans , Male , Middle Aged , Nerve Degeneration/pathology , Trinucleotide Repeat Expansion/geneticsABSTRACT
BACKGROUND: Older age is a major risk factor for severe COVID-19 disease which has been associated with a variety of neurologic complications, both acutely and chronically. OBJECTIVE: We sought to determine whether milder COVID-19 disease in older vulnerable individuals is also associated with cognitive and behavioral sequelae. METHODS: Neuropsychological, behavioral, and clinical outcomes before and after contracting COVID-19 disease, were compared in members of two ongoing longitudinal studies, the Arizona APOE Cohort and the national Alzheimer's Disease Research Center (ADRC). RESULTS: 152 APOE and 852 ADRC cohort members, mean age overall roughly 70 years, responded to a survey that indicated 21 APOE and 57 ADRC members had contracted COVID-19 before their ensuing (post-COVID) study visit. The mean interval between test sessions that preceded and followed COVID was 2.2 years and 1.2 years respectively for the APOE and ADRC cohorts. The magnitude of change between the pre and post COVID test sessions did not differ on any neuropsychological measure in either cohort. There was, however, a greater increase in informant (but not self) reported cognitive change in the APOE cohort (pâ=â0.018), but this became nonsignificant after correcting for multiple comparisons. CONCLUSION: Overall members of both cohorts recovered well despite their greater age-related vulnerability to more severe disease.
Subject(s)
Alzheimer Disease , COVID-19 , Cognitive Dysfunction , Humans , Aged , Neuropsychological Tests , COVID-19/complications , Cognition , Longitudinal Studies , Alzheimer Disease/complications , Alzheimer Disease/psychology , Apolipoproteins E/genetics , Apolipoprotein E4 , Cognitive Dysfunction/etiologyABSTRACT
Cerebral white matter rarefaction (CWMR) was considered by Binswanger and Alzheimer to be due to cerebral arteriolosclerosis. Renewed attention came with CT and MR brain imaging, and neuropathological studies finding a high rate of CWMR in Alzheimer disease (AD). The relative contributions of cerebrovascular disease and AD to CWMR are still uncertain. In 1181 autopsies by the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND), large-format brain sections were used to grade CWMR and determine its vascular and neurodegenerative correlates. Almost all neurodegenerative diseases had more severe CWMR than the normal control group. Multivariable logistic regression models indicated that Braak neurofibrillary stage was the strongest predictor of CWMR, with additional independently significant predictors including age, cortical and diencephalic lacunar and microinfarcts, body mass index, and female sex. It appears that while AD and cerebrovascular pathology may be additive in causing CWMR, both may be solely capable of this. The typical periventricular pattern suggests that CWMR is primarily a distal axonopathy caused by dysfunction of the cell bodies of long-association corticocortical projection neurons. A consequence of these findings is that CWMR should not be viewed simply as "small vessel disease" or as a pathognomonic indicator of vascular cognitive impairment or vascular dementia.
Subject(s)
Alzheimer Disease , Cerebrovascular Disorders , Dementia, Vascular , White Matter , Female , Humans , White Matter/pathology , Brain/pathology , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/diagnostic imaging , Cerebrovascular Disorders/pathology , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/pathology , Dementia, Vascular/pathologyABSTRACT
BACKGROUND: The APOE epsilon4 allele is associated with the risk of late-onset Alzheimer's disease. The age at which memory decline diverges among persons who are homozygous for the APOE epsilon4 allele, those who are heterozygous for the allele, and noncarriers is unknown. METHODS: Using local advertisements, we recruited cognitively normal subjects between the ages of 21 and 97 years, who were grouped according to their APOE epsilon4 status. We then followed the subjects with longitudinal neuropsychological testing. Anyone in whom mild cognitive impairment or dementia developed during follow-up was excluded. We compared the rates of decline in predetermined cognitive measures between carriers and noncarriers of the APOE epsilon4 allele, using a mixed model for longitudinal change with age. RESULTS: We analyzed 815 subjects: 317 APOE epsilon4 carriers (79 who were homozygous for the APOE epsilon4 allele and 238 who were heterozygous) and 498 noncarriers. Carriers, as compared with noncarriers, were generally younger (mean age, 58.0 vs. 61.4 years; P<0.001) and were followed for a longer period (5.3 vs. 4.7 years, P=0.01), with an equivalent duration of formal education (15.4 years) and proportion of women (69%). Longitudinal decline in memory in carriers began before the age of 60 years and showed greater acceleration than in noncarriers (P=0.03), with a possible allele-dose effect (P=0.008). We observed similar although weaker effects on measures of visuospatial awareness and general mental status. CONCLUSIONS: Age-related memory decline in APOE epsilon4 carriers diverges from that of noncarriers before the age of 60 years, despite ongoing normal clinical status.
Subject(s)
Apolipoprotein E4/genetics , Memory Disorders/genetics , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Heterozygote , Homozygote , Humans , Longitudinal Studies , Male , Memory , Memory Disorders/diagnosis , Middle Aged , Neuropsychological Tests , Young AdultABSTRACT
Brains of 42 COVID-19 decedents and 107 non-COVID-19 controls were studied. RT-PCR screening of 16 regions from 20 COVID-19 autopsies found SARS-CoV-2 E gene viral sequences in 7 regions (2.5% of 320 samples), concentrated in 4/20 subjects (20%). Additional screening of olfactory bulb (OB), amygdala (AMY) and entorhinal area for E, N1, N2, RNA-dependent RNA polymerase, and S gene sequences detected one or more of these in OB in 8/21 subjects (38%). It is uncertain whether these RNA sequences represent viable virus. Significant histopathology was limited to 2/42 cases (4.8%), one with a large acute cerebral infarct and one with hemorrhagic encephalitis. Case-control RNAseq in OB and AMY found more than 5000 and 700 differentially expressed genes, respectively, unrelated to RT-PCR results; these involved immune response, neuronal constituents, and olfactory/taste receptor genes. Olfactory marker protein-1 reduction indicated COVID-19-related loss of OB olfactory mucosa afferents. Iba-1-immunoreactive microglia had reduced area fractions in cerebellar cortex and AMY, and cytokine arrays showed generalized downregulation in AMY and upregulation in blood serum in COVID-19 cases. Although OB is a major brain portal for SARS-CoV-2, COVID-19 brain changes are more likely due to blood-borne immune mediators and trans-synaptic gene expression changes arising from OB deafferentation.
Subject(s)
COVID-19 , SARS-CoV-2 , Brain , Gene Expression , Humans , ImmunityABSTRACT
Cognitive complaints are common in any adult neurology practice, and may present in a variety of ways other than classic "memory loss." In this article, the author reviews a simple approach to a symptom-based differential diagnosis, including recognition of impairment in several key cognitive domains as well as associated symptoms such as motor disorders, psychosis, and sleep disturbance. Standard evaluation and management strategies of the most common presentations of cognitive decline in an outpatient setting are reviewed.
Subject(s)
Cognition Disorders/diagnosis , Cognition Disorders/therapy , Cognition Disorders/psychology , Diagnosis, Differential , Humans , Neuropsychological Tests , Psychotic Disorders/diagnosis , Psychotic Disorders/psychology , Psychotic Disorders/therapyABSTRACT
BACKGROUND: To provide preliminary validation data on a self- or informant-report multidimensional questionnaire of symptoms associated with neurodegenerative disorders. METHODS: Participants from 2 trials (n = 125), the Arizona APOE Cohort and the Arizona Alzheimer's Disease Center, completed the Multidimensional Assessment of Neurodegenerative Symptoms questionnaire (MANS) and other related measures. RESULTS: Measures of central tendency are provided for the sample as a whole and by cognitive status. Internal consistency of the MANS is excellent (alpha = 0.98). Factor analysis suggests 4 factors. Correlational analyses support the construct validity of the MANS with moderate to high (r = 0.54-0.87) correlations between the MANS and measures of mood, cognition and daily functioning. CONCLUSION: Results provide initial support for the MANS as a brief measure that is a reliable and valid indicator of cognitive, personality, functional and motor symptoms potentially related to neurodegenerative etiologies. Further research with the MANS is warranted.