33 results on '"Katya Numbers"'
Search Results
2. Network of mental activities, cognitive function and depression in older men and women
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Ella G. Hopkins, Patrick J. Leman, Matti Cervin, Katya Numbers, Henry Brodaty, Nicole A. Kochan, Perminder S. Sachdev, and Oleg N. Medvedev
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Psychiatry and Mental health ,Biological Psychiatry - Published
- 2023
3. The Heritability of Subjective Cognitive Complaints in Older Australian Twins
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Amanda E. Selwood, Vibeke S. Catts, Katya Numbers, Teresa Lee, Anbupalam Thalamuthu, Margaret J. Wright, and Perminder S. Sachdev
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Psychiatry and Mental health ,Clinical Psychology ,General Neuroscience ,General Medicine ,Geriatrics and Gerontology - Abstract
Background: Subjective cognitive complaints (SCCs) may be a precursor to mild cognitive impairment (MCI) and dementia. Objective: This study aimed to examine the heritability of SCCs, correlations between SCCs and memory ability, and the influence of personality and mood on these relationships. Methods: Participants were 306 twin pairs. The heritability of SCCs and the genetic correlations between SCCs and memory performance, personality, and mood scores were determined using structural equation modelling. Results: SCCs were low to moderately heritable. Memory performance, personality and mood were genetically, environmentally, and phenotypically correlated with SCCs in bivariate analysis. However, in multivariate analysis, only mood and memory performance had significant correlations with SCCs. Mood appeared to be related to SCCs by an environmental correlation, whereas memory performance was related to SCCs by a genetic correlation. The link between personality and SCCs was mediated by mood. SCCs had a significant amount of both genetic and environmental variances not explained by memory performance, personality, or mood. Conclusion: Our results suggest that SCCs are influenced both by a person’s mood and their memory performance, and that these determinants are not mutually exclusive. While SCCs had genetic overlap with memory performance and environmental association with mood, much of the genetic and environmental components that comprised SCCs were specific to SCCs, though these specific factors are yet to be determined.
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- 2023
4. Critical periods for cognitive reserve building activities for late life global cognition and cognitive decline: the Sydney memory and aging cohort study
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Princess Neila Litkouhi, Katya Numbers, Michael Valenzuela, John D Crawford, Ben C. P. Lam, Princess Noosha Litkouhi, Perminder S. Sachdev, Nicole A. Kochan, and Henry Brodaty
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Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Experimental and Cognitive Psychology ,Geriatrics and Gerontology - Published
- 2023
5. Establishing conversion of the 16‐item <scp>Informant Questionnaire on Cognitive Decline in the Elderly</scp> scores into interval‐level data across multiple samples using <scp>Rasch</scp> methodology
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Quoc Cuong Truong, Katya Numbers, Carol C. Choo, Adam C. Bentvelzen, Vibeke S. Catts, Matti Cervin, Anthony F. Jorm, Nicole A. Kochan, Henry Brodaty, Perminder S. Sachdev, and Oleg N. Medvedev
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Psychiatry and Mental health ,Geriatrics and Gerontology ,Gerontology - Published
- 2023
6. A novel approach to investigate depression symptoms in the aging population using generalizability theory
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Sruthy S. Kumar, Alexander G. Merkin, Katya Numbers, Perminder S. Sachdev, Henry Brodaty, Nicole A. Kochan, Julian N. Trollor, Susan Mahon, and Oleg Medvedev
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Aged, 80 and over ,Psychiatric Status Rating Scales ,Aging ,Psychiatry and Mental health ,Clinical Psychology ,Psychometrics ,Depression ,Humans ,Reproducibility of Results ,Geriatric Assessment ,Aged - Abstract
As depression is common in older people and confers significant risk for dementia, its accurate assessment is essential. The 15-item Geriatric Depression Scale (GDS-15) is a widely used assessment tool for measuring depression in aged populations, and its psychometric properties have been recently improved using Rasch analysis. However, its temporal reliability and ability to distinguish between dynamic and enduring symptoms of depression have not been examined using the appropriate methodology. Generalizability theory (G theory) is a suitable method to distinguish between enduring and dynamic symptoms of depression and to evaluate the reliability of the GDS-15 scores and sources of measurement error. We applied G theory to the longitudinal GDS-15 data of 354 participants from the Sydney Memory and Ageing Study, collected biennially over 10 years, from individuals aged 70 years and older. The GDS-15 demonstrated strong reliability and generalizability of its test scores in measuring enduring symptoms of depression (
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- 2022
7. Enhancing precision of the Telephone Interview for Cognitive Status–Modified (TICS-M) using the Rasch model
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Quoc C. Truong, Carol Choo, Katya Numbers, Adam Bentvelzen, Alexander G. Merkin, Henry Brodaty, Nicole A. Kochan, Valery L. Feigin, Perminder S. Sachdev, and Oleg N. Medvedev
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Psychiatry and Mental health ,Clinical Psychology - Published
- 2023
8. Using network analysis to validate domains of the modified telephone interview for cognitive status
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Truong Quoc Cuong, Matti Cervin, Carol C. Choo, Katya Numbers, Adam C. Bentvelzen, Alexander G. Merkin, Perminder S. Sachdev, Valery L. Feigin, Henry Brodaty, Nicole A. Kochan, and Oleg N. Medvedev
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Clinical Biochemistry ,General Medicine ,Biochemistry - Published
- 2023
9. Longitudinal changes in participant and informant reports of subjective cognitive complaints are associated with dementia risk
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Katya Numbers, Ben C. P. Lam, John D. Crawford, Nicole A. Kochan, Perminder S. Sachdev, and Henry Brodaty
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Aging ,Cognitive Neuroscience - Abstract
BackgroundIndividuals with subjective cognitive complaints (SCCs) are at an increased risk of dementia. Questions remain about participant-reported versus informant-reported SCCs as indicators of future dementia and about longitudinal changes in participant-and informant-reported SCCs and risk of incident dementia.MethodParticipants were 873 older adults (M = 78.65-years; 55% female) and 849 informants from the Sydney Memory and Ageing Study. Comprehensive assessments occurred biennially, and clinical diagnoses were made by expert consensus for 10-years. SCCs were participants’ and informants’ responses to a single binary question concerning their/the participant’s memory decline (Yes/No) over the first 6-years. Categorical latent growth curve analyses, using the logit transformation, were used to model SCC change over time. Associations of initial propensity to report SCCs at baseline, and change in propensity to report SCCs over time, with dementia risk were examined using Cox regression.Results70% of participants reported SCCs at baseline, with a proportional increase in the odds of reporting by 11% for each additional year in the study. In contrast, 22% of informants reported SCCs at baseline, with a proportional increase by 30% in the odds of reporting per year. Participants’ initial level of (p = 0.007), but not change in SCC reporting (p = 0.179), was associated with risk of dementia controlling for all covariates. Both informants’ initial level of (p p p’s ConclusionThese data suggest that informants’ initial impressions, and increased reporting, of SCCs appear to be uniquely prognostic of future dementia compared to participants’, even based on a single SCC question.
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- 2023
10. Comparison of computerised and pencil-and-paper neuropsychological assessments in older culturally and linguistically diverse Australians - CORRIGENDUM
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Zara A. Page, Karen Croot, Perminder S. Sachdev, John D. Crawford, Ben C.P. Lam, Henry Brodaty, Amanda Miller Amberber, Katya Numbers, and Nicole A. Kochan
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Psychiatry and Mental health ,Clinical Psychology ,General Neuroscience ,Australia ,Humans ,Neurology (clinical) ,Cultural Diversity ,Neuropsychological Tests ,Aged - Published
- 2022
11. Instrumental Activities of Daily Living by Subjective and Objective Measures: The Impact of Depression and Personality
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Katya, Numbers, Sujin, Jang, Henry, Brodaty, Perminder S, Sachdev, Brian, Draper, and Simone, Reppermund
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Aging ,Cognitive Neuroscience - Abstract
ObjectivePrevious research shows that depression and personality are independently associated with self- and informant-reports of the ability to perform instrumental activities of daily living (IADLs). However, less is known about the association between depression and personality and performance-based measures of IADLs. We aimed to determine how depression and personality predict self-and informant-reports of IADL compared to performance-based measures of IADLs in a sample of older adults with normal cognition (NC) and Mild Cognitive Impairment (MCI).MethodsParticipants consisted of 385 older adults with NC (n = 235), or a diagnosis of MCI (n = 150), aged between 76 and 99-years from the Sydney Memory and Ageing Study. Participants underwent comprehensive neuropsychological and clinical assessments to determine global cognition and clinical diagnoses. Personality traits were measured by the NEO Five-Factor Inventory (NEO-FFI) and depression by the Geriatric Depression Scale (GDS). Subjective IADLs were self- and informant-reported Bayer Activities of Daily Living (B-ADL) scales and objective IADL was the Sydney Test of Activities of Daily Living in Memory Disorders (STAM). Linear regressions examined the relationship between depression and personality and the three types of IADL measures, controlling for all covariates and global cognition.ResultsParticipant-reported IADL, although associated with global cognition, was more strongly associated with GDS and NEO-FFI scores (conscientiousness and neuroticism). Informant-reported IADL was strongly associated with both global cognition and participants’ GDS scores. STAM scores were not associated with participants’ GDS or NEO-FFI scores; instead, they were predicted by demographics and global cognition.ConclusionThese results suggest that performance-based measures of IADL may provide more objective and reliable insight into an individual’s underlying functional ability and are less impacted by the participants’ mood and personality compared to subjectively reported IADL. We argue that performance-based IADL measures are preferable when trying to accurately assess everyday functional ability and its relationship to cognitive status. Where performance-based measures are not available (e.g., in some clinical settings), informant ratings should be sought as they are less influenced by the participant’s personality and mood compared to self-reports.
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- 2022
12. The influence of rs53576 polymorphism in the oxytocin receptor (OXTR) gene on empathy in healthy adults by subtype and ethnicity: a systematic review and meta-analysis
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Julie D. Henry, Perminder S. Sachdev, Sarah A. Grainger, Katya Numbers, Rhiagh Cleary, Karen A. Mather, Henry Brodaty, Anbupalam Thalamuthu, Russell J. Chander, Nicola J. Armstrong, and Nicole A. Kochan
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Social cognition ,Strictly standardized mean difference ,General Neuroscience ,media_common.quotation_subject ,Meta-analysis ,Cohort ,SNP ,Empathy ,Single-nucleotide polymorphism ,Psychology ,Oxytocin receptor ,media_common ,Clinical psychology - Abstract
Empathy is essential for navigating complex social environments. Prior work has shown associations between rs53576, a single nucleotide polymorphism (SNP) located in the oxytocin receptor gene (OXTR), and generalized empathy. We undertook a systematic review and meta-analysis to assess the effects of rs53576 on subdomains of empathy, specifically cognitive empathy (CE) and affective empathy (AE), in healthy adults. Twenty cohorts of 8933 participants aged 18–98 were identified, including data from the Sydney Memory and Ageing Study, a cohort of older community adults. Meta-analyses found G homozygotes had greater generalized empathic abilities only in young to middle-aged adults. While meta-analyses of empathy subdomains yielded no significant overall effects, there were differential effects based on ethnicity. G homozygotes were associated with greater CE abilities in Asian cohorts (standardized mean difference; SMD: 0.09 [2.8·10−3–0.18]), and greater AE performance in European cohorts [SMD: 0.12 (0.04–0.21)]. The current literature highlights a need for further work that distinguishes between genetic and ethnocultural effects and explores effects of advanced age on this relationship.
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- 2021
13. Emerging Neuropsychiatric Symptoms May Represent an Early Manifestation of Preclinical Alzheimer's Disease
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Katya Numbers
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Alzheimer Disease ,Humans ,Neuropsychological Tests ,Biological Psychiatry - Published
- 2022
14. Networks of inflammation, depression, and cognition in aging males and females
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Rebecca A. Chalmers, Matti Cervin, Carol Choo, Bernhard T. Baune, Julian N. Trollor, Katya Numbers, Perminder S. Sachdev, Henry Brodaty, Nicole A. Kochan, and Oleg N. Medvedev
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Male ,Inflammation ,Aged, 80 and over ,Aging ,Cognition ,Depression ,Memory ,Humans ,Female ,Geriatrics and Gerontology ,Biomarkers ,Aged - Abstract
Background Prioritizing the maintenance of healthy cognitive aging and personalizing preventive interventions to enhance their effectiveness is crucial as the global population ages. Systemic inflammation and depression in older people have been associated with decreased levels of cognition but results have been inconsistent. Aims To explore the interactive network of inflammation, depression and cognition by sex in older people. Methods We used novel network analysis to explore the unique associations between inflammatory biomarkers, depression, cognition, and somatic, genetic, and lifestyle risk factors in an older (aged 70–90 years), non-demented, community-dwelling sample from the longitudinal Sydney Memory and Aging Study (N = 916) at baseline and at a two-year follow-up. Results The networks of biomarkers, depression, cognition, and relevant covariates were significantly different between males and females. A stable negative link between depression and cognition was found in females only; a stable positive association between biomarker interleukin-6 and depression was found in females only; and a stable positive association between biomarker interleukin-8 and alcohol was found in females only. For both males and females, a stable, positive relationship was found between the presence of APOE-ε4 gene and biomarker C-reactive protein; between education and cognition; and between biomarker interleukin-6 and all other biomarkers. Conclusions These findings suggest different psychophysiological mechanisms underlie the interactive network of biomarkers, depression and cognition in males and females that should be considered when designing personalized preventive interventions to maintain cognitively healthy aging.
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- 2022
15. Does Antihypertensive Use Moderate the Effect of Blood Pressure on Cognitive Decline in Older People?
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Katya Numbers, Ben C. P. Lam, Henry Brodaty, John D. Crawford, Julian N. Trollor, Perminder S. Sachdev, Brian Draper, Matthew J. Lennon, Anbupalam Thalamuthu, and Nicole A. Kochan
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Aging ,medicine.medical_specialty ,Systole ,Neuropsychological Tests ,Cohort Studies ,Internal medicine ,medicine ,Humans ,Dementia ,Cognitive Dysfunction ,Longitudinal Studies ,Cognitive decline ,Antihypertensive Agents ,Aged ,Aged, 80 and over ,business.industry ,Proportional hazards model ,Australia ,Neuropsychology ,Cognition ,medicine.disease ,Blood pressure ,Hypertension ,Cohort ,Cardiology ,Geriatrics and Gerontology ,business - Abstract
Background While midlife hypertension is deleterious, late-life hypertension has been associated with better cognitive outcomes in several studies. Many questions remain, including the relative benefit or harm of a blood pressure (BP) target and antihypertensive therapy of Methods The Sydney Memory and Aging Study (n = 1015) comprises a cohort of 70- to 90-year-olds, who were followed biennially for 8 years. Global cognition was assessed with a battery of 10 neuropsychological tests. Blood pressure was measured at Waves 1 and 2 and classified into 3 systolic groupings: group 1 (≤120 mmHg), group 2 (121–140 mmHg), and group 3 (>140 mmHg). Multiple regression, linear mixed modeling, and Cox regression examined the effect of BP and antihypertensives. Results There were no overall significant differences in global cognition or dementia between the disparate BP groups. However, in those not taking antihypertensives, the systolic BP (SBP) > 140 mmHg group had a significantly worse global cognitive trajectory compared to SBP ≤ 120 mmHg (b = −0.067, 95% CI [−0.129, −0.006], p = .030). Within the SBP ≤ 120 mmHg group those taking antihypertensives had significantly worse global cognition trajectories compared to those not taking antihypertensives even when controlling for past history of hypertension (b = −0.077, 95% CI [−0.147, −0.007], p = .030). Conclusions Untreated hypertension in old age is related to worse global cognitive decline. However, ongoing treatment at new recommendations of lower SBP targets may be related to poorer cognitive decline and should be considered carefully in older populations.
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- 2020
16. Associations between social connections and cognition: a global collaborative individual participant data meta-analysis
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Suraj Samtani, Gowsaly Mahalingam, Ben Chun Pan Lam, Darren M Lipnicki, Maria Fernanda Lima-Costa, Sergio Luís Blay, Erico Castro-Costa, Xiao Shifu, Maëlenn Guerchet, Pierre-Marie Preux, Antoine Gbessemehlan, Ingmar Skoog, Jenna Najar, Therese Rydberg Sterner, Nikolaos Scarmeas, Ki-Woong Kim, Steffi Riedel-Heller, Susanne Röhr, Alexander Pabst, Suzana Shahar, Katya Numbers, Mary Ganguli, Erin Jacobsen, Tiffany F Hughes, Michael Crowe, Tze Pin Ng, Jane Maddock, Anna Marseglia, René Mélis, Dorota Szcześniak, Henrik Wiegelmann, Myrra Vernooij-Dassen, Yun-Hee Jeon, Perminder S Sachdev, and Henry Brodaty
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Male ,Memory Disorders ,Alzheimer`s disease Donders Center for Medical Neuroscience [Radboudumc 1] ,Health (social science) ,Neurodegenerative Diseases ,United States ,Healthcare improvement science Radboud Institute for Health Sciences [Radboudumc 18] ,Cohort Studies ,Psychiatry and Mental health ,Cognition ,Humans ,Female ,Dementia ,Longitudinal Studies ,Geriatrics and Gerontology ,Family Practice - Abstract
Contains fulltext : 287762.pdf (Publisher’s version ) (Open Access) BACKGROUND: Poor social connections (eg, small networks, infrequent interactions, and loneliness) are modifiable risk factors for cognitive decline. Existing meta-analyses are limited by reporting aggregate responses, a focus on global cognition, and combining social measures into single constructs. We aimed to investigate the association between social connection markers and the rate of annual change in cognition (ie, global and domain-specific), as well as sex differences, using an individual participant data meta-analysis. METHODS: We harmonised data from 13 longitudinal cohort studies of ageing in North America, South America, Europe, Africa, Asia, and Australia. Studies were eligible for inclusion if they had baseline data for social connection markers and at least two waves of cognitive scores. Follow-up periods ranged from 0 years to 15 years across cohorts. We included participants with cognitive data for at least two waves and social connection data for at least one wave. We then identified and excluded people with dementia at baseline. Primary outcomes were annual rates of change in global cognition and cognitive domain scores over time until final follow-up within each cohort study analysed by use of an individual participant data meta-analysis. Linear mixed models within cohorts used baseline social connection markers as predictors of the primary outcomes. Effects were pooled in two stages using random-effects meta-analyses. We assessed the primary outcomes in the main (partially adjusted) and fully adjusted models. Partially adjusted models controlled for age, sex, and education; fully adjusted models additionally controlled for diabetes, hypertension, smoking, cardiovascular risk, and depression. FINDINGS: Of the 40 006 participants in the 13 cohort studies, we excluded 1392 people with dementia at baseline. 38 614 individual participants were included in our analyses. For the main models, being in a relationship or married predicted slower global cognitive decline (b=0·010, 95% CI 0·000-0·019) than did being single or never married; living with others predicted slower global cognitive (b=0·007, 0·002-0·012), memory (b=0·017, 0·006-0·028), and language (b=0·008, 0·000-0·015) decline than did living alone; and weekly interactions with family and friends (b=0·016, 0·006-0·026) and weekly community group engagement (b=0·030, 0·007-0·052) predicted slower memory decline than did no interactions and no engagement. Never feeling lonely predicted slower global cognitive (b=0·047, 95% CI 0·018-0·075) and executive function (b=0·047, 0·017-0·077) decline than did often feeling lonely. Degree of social support, having a confidante, and relationship satisfaction did not predict cognitive decline across global cognition or cognitive domains. Heterogeneity was low (I(2)=0·00-15·11%) for all but two of the significant findings (association between slower memory decline and living with others [I(2)=58·33%] and community group engagement, I(2)=37·54-72·19%), suggesting robust results across studies. INTERPRETATION: Good social connections (ie, living with others, weekly community group engagement, interacting weekly with family and friends, and never feeling lonely) are associated with slower cognitive decline. FUNDING: EU Joint Programme-Neurodegenerative Disease Research grant, funded by the National Health and Medical Research Council Australia, and the US National Institute on Aging of the US National Institutes of Health.
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- 2022
17. Comparison of Computerised and Pencil-and-Paper Neuropsychological Assessments in Older Culturally and Linguistically Diverse Australians
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Zara A. Page, Karen Croot, Perminder S. Sachdev, John D. Crawford, Ben C.P. Lam, Henry Brodaty, Amanda Miller Amberber, Katya Numbers, and Nicole A. Kochan
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Psychiatry and Mental health ,Clinical Psychology ,General Neuroscience ,Australia ,Humans ,Linguistics ,Dementia ,Neurology (clinical) ,Cultural Diversity ,Neuropsychological Tests ,Aged - Abstract
Objectives:Computerised neuropsychological assessments (CNAs) are proposed as an alternative method of assessing cognition to traditional pencil-and-paper assessment (PnPA), which are considered the “gold standard” for diagnosing dementia. However, limited research has been conducted with culturally and linguistically diverse (CALD) individuals. This study investigated the suitability of PnPAs and CNAs for measuring cognitive performance in a heterogenous sample of older, Australian CALD English-speakers compared to a native English-speaking background (ESB) sample.Methods:Participants were 1037 community-dwelling individuals aged 70–90 years without a dementia diagnosis from the Sydney Memory and Ageing Study (873 ESB, 164 CALD). Differences in the level and pattern of cognitive performance in the CALD group were compared to the ESB group on a newly developed CNA and a comprehensive PnPA in English, controlling for covariates. Multiple hierarchical regression was used to identify the extent to which linguistic and acculturation variables explained performance variance.Results:CALD participants’ performance was consistently poorer than ESB participants on both PnPA and CNA, and more so on PnPA than CNA, controlling for socio-demographic and health factors. Linguistic and acculturation variables together explained approximately 20% and 25% of CALD performance on PnPA and CNA respectively, above demographics and self-reported computer use.Conclusions:Performances of CALD and ESB groups differed more on PnPAs than CNAs, but caution is needed in concluding that CNAs are more culturally-appropriate for assessing cognitive decline in older CALD individuals. Our findings extend current literature by confirming the influence of linguistic and acculturation variables on cognitive assessment outcomes for older CALD Australians.
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- 2021
18. Are lonely older adults more vulnerable to mental health issues during pandemics?
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Suraj Samtani, Katya Numbers, and Ashley Stevens
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Psychiatry and Mental health ,Clinical Psychology ,2019-20 coronavirus outbreak ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pandemic ,medicine ,Geriatrics and Gerontology ,Psychology ,Psychiatry ,Gerontology ,Mental health - Published
- 2021
19. Enhancing precision of the 16-item Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE-16) using Rasch methodology
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Katya Numbers, Carol C Choo, Alexander Merkin, Nicole A. Kochan, Valery L. Feigin, Quoc Cuong Truong, Perminder S. Sachdev, Henry Brodaty, and Oleg N. Medvedev
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Rasch model ,Separation (statistics) ,Sample (statistics) ,medicine.disease ,Psychiatry and Mental health ,Clinical Psychology ,Informant Questionnaire on Cognitive Decline in the Elderly ,Scale (social sciences) ,medicine ,Dementia ,Geriatrics and Gerontology ,Cognitive decline ,Psychology ,Gerontology ,Reliability (statistics) ,Clinical psychology - Abstract
Objective: This study aimed to investigate psychometric properties and enhance precision of the 16-item Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE-16) up to interval-level scale using Rasch methodology. Design: Partial Credit Rasch model was applied to the IQCODE-16 scores using longitudinal data spanning 10 years of biennial follow-up. Setting: Community-dwelling older adults aged 70–90 years and their informants, living in Sydney, Australia, participated in the longitudinal Sydney Memory and Ageing Study (MAS). Participants: The sample included 400 participants of the MAS aged 70 years and older, 109 out of those were diagnosed with dementia 10 years after the baseline assessment. Measurements: The IQCODE-16. Results: Initial analysis indicated excellent reliability of the IQCODE-16, Person Separation Index (PSI) = 0.92, but there were four misfitting items and local dependency issues. Combining locally dependent items into four super-items resulted in the best Rasch model fit with no misfitting or locally dependent items, strict unidimensionality, strong reliability, and invariance across person factors such as participants’ diagnosis and relationship to their informants, as well as informants’ age and sex. This permitted the generation of conversion algorithms to transform ordinal scores into interval data to enhance precision of measurement. Conclusions: The IQCODE-16 demonstrated strong reliability and satisfied expectations of the unidimensional Rasch model after minor modifications. Ordinal-to-interval transformation tables published here can be used to increase accuracy of the IQCODE-16 without altering its current format. These findings could contribute to enhancement of precision in assessing clinical conditions such as cognitive decline in older people.
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- 2021
20. Clinical investigation of dynamic and enduring aspects of global cognition in aged population
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Quoc Cuong Truong, Henry Brodaty, Oleg N. Medvedev, Nicole A. Kochan, Alexander Merkin, Katya Numbers, Perminder S. Sachdev, Valery L. Feigin, and Carol C Choo
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Male ,Longitudinal data ,Clinical Biochemistry ,Sensitivity and Specificity ,Biochemistry ,Cognition ,Clinical investigation ,mental disorders ,medicine ,Humans ,Dementia ,Generalizability theory ,Aged ,Aged, 80 and over ,Age Factors ,General Medicine ,Mental Status and Dementia Tests ,medicine.disease ,Explained variation ,Aged population ,Telephone interview ,Female ,Psychology ,Clinical psychology - Abstract
BACKGROUND A major issue in evaluating the cognitive status of ageing populations is a clear distinction between enduring and dynamic aspects of global cognition necessary for evaluating risks of dementia and effectiveness of preventive interventions. MATERIALS AND METHODS Generalizability Theory was applied to investigate dynamic and enduring aspects of global cognition using longitudinal data over 10 years of follow-up. Measures included the Mini-Mental Status Examination (MMSE) and the Telephone Interview for Cognitive Status-modified (TICS-M). The sample (N = 238) included 154 females, mean age = 76.54 years, SD = 3.94 from the Sydney Memory and Ageing Study. RESULTS The MMSE measured dynamic and enduring aspects of cognition to a comparable degree with 56% of variance explained by enduring aspects and 44% by dynamic aspects and showed low sensitivity/high specificity in detecting dementia. A shortened version of the MMSE (MMSE-D8) better captured dynamic aspects of cognition after removing three items less sensitive to change. The TICS-M predominantly measured enduring aspects of cognition (72%) with the remaining 28% due to dynamic aspects and displayed high sensitivity/high specificity for dementia screening. CONCLUSIONS The MMSE measures both dynamic and enduring cognitive aspects and is suitable for general clinical assessments, while the MMSE-D8 can be used to monitor transitory changes of global cognition over time. The TICS-M is more useful for measuring enduring features of cognition and screening for dementia. Our findings highlight the value of generalizability theory to distinguish dynamic and enduring features of cognition, which may contribute to preventive interventions and monitoring cognitive ability over time.
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- 2021
21. Validation and Normative Data for the Modified Telephone Interview for Cognitive Status: The Sydney Memory and Ageing Study
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Henry Brodaty, Adam Theobald, Adam Bentvelzen, Nicole A. Kochan, Perminder S. Sachdev, Katya Numbers, Kate Maston, Kristan Kang, John D. Crawford, Melissa J. Slavin, and Simone Reppermund
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Male ,050103 clinical psychology ,Psychometrics ,Neuropsychological Tests ,Sensitivity and Specificity ,Interviews as Topic ,03 medical and health sciences ,0302 clinical medicine ,mental disorders ,medicine ,Humans ,Dementia ,Cognitive Dysfunction ,0501 psychology and cognitive sciences ,Longitudinal Studies ,Prospective Studies ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,05 social sciences ,Neuropsychology ,Reproducibility of Results ,Construct validity ,Cognition ,Neuropsychological test ,medicine.disease ,Telephone ,Cognitive test ,Telephone interview ,Normative ,Female ,Geriatrics and Gerontology ,business ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
Objectives Telephone-based cognitive screens, such as the Telephone Interview for Cognitive Status (TICS), can potentially reduce the barriers and costs of assessing older adults. However, validation of clinically relevant psychometric properties is lacking in a large and comprehensively assessed sample of older adults. Furthermore, published normative data may lack sensitivity as they have not used regression-based demographic corrections or accounted for cases with subsequent dementia. We address these gaps using the modified TICS (TICS-M; a modified, 13-item, 39-point version) and provide an online norms calculator for clinicians and researchers. Design Prospective longitudinal study. Setting Sydney, Australia. Participants A total of 617 community-living older adults, aged from 71 to 91 years. Measurements The measures used included the TICS-M, the Mini-Mental State Examination (MMSE), Addenbrooke's Cognitive Examination-Revised (ACE-R), and a comprehensive neuropsychological test battery. Descriptive statistics, correlations, area under the curve, and regression analyses were used to determine the validity and normative properties of the TICS-M. Results TICS-M total scores (mean = 24.20; SD = 3.76) correlated well with the MMSE (0.70) and ACE-R (0.80) and moderately with neuropsychological tests tested noncontemporaneously. A cutoff score of 21 or lower reliably distinguished between those with and without incident dementia after 1 year (sensitivity = 77%; specificity = 88%) but was less reliable at distinguishing mild cognitive impairment from normal cognition. TICS-M scores decreased with age and increased with higher education levels. The robust normative sample, which excluded incident dementia cases, scored higher on the TICS-M and with less variability than the whole sample. An online calculator is provided to compute regression-based norms and reliable change statistics. Conclusions In a large sample of community-dwelling older adults, the TICS-M performed well in terms of construct validity against typical screening tools and neuropsychological measures and diagnostic validity for incident dementia. The comprehensive, regression-based, and robust normative data provided will help improve the sensitivity, accessibility, and cost-effectiveness of cognitive testing with older adults. J Am Geriatr Soc 67:2108-2115, 2019.
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- 2019
22. Performance-Based vs Informant-Reported Instrumental Activities of Daily Living in Predicting Dementia
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Simone Reppermund, Perminder S. Sachdev, Sujin Jang, Ben C. P. Lam, Henry Brodaty, and Katya Numbers
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Male ,Gerontology ,Activities of daily living ,Neuropsychological Tests ,Logistic regression ,Activities of Daily Living ,mental disorders ,medicine ,Humans ,Dementia ,Cognitive Dysfunction ,Prospective Studies ,Prospective cohort study ,General Nursing ,Aged ,Aged, 80 and over ,business.industry ,Health Policy ,General Medicine ,Odds ratio ,Mental Status and Dementia Tests ,medicine.disease ,Confidence interval ,Test (assessment) ,Female ,Geriatric Depression Scale ,Geriatrics and Gerontology ,business ,human activities - Abstract
Identifying individuals at risk of developing dementia may be aided by early detection of functional impairments. The aims of the present study were to examine differences in informant-reported and performance-based measures of instrumental activities of daily living (IADL) and to assess whether a performance-based IADL measure contributes additional unique variance over informant reports in predicting incident dementia over 4 years.Prospective cohort study (Sydney Memory and Ageing Study).Eastern Suburbs, Sydney, Australia.307 community-dwelling individuals (60.6% female) aged between 76 and 96 years with normal cognition (NC; n = 190) or mild cognitive impairment (MCI; n = 117).IADL ability was assessed with the performance-based Sydney Test of Activities of Daily Living in Memory Disorders (STAM) and the Bayer-Activities of Daily Living (B-ADL) informant report, at baseline and 4-year follow-up. Covariates included age, sex, education, Mini-Mental State Examination and Geriatric Depression Scale scores, arthritis, vision impairment, cardiovascular risk, and number of medications. Logistic regressions were conducted to examine the longitudinal association between the 2 types of IADL measures and incident dementia.Logistic regressions showed that performance-based IADL impairment at baseline [odds ratio (OR) = 0.83, 95% confidence interval (CI) 0.77, 0.90; P.001] and decline in performance-based IADL function (OR = 0.82, 95% CI 0.73, 0.91; P.001) were associated with incident dementia over 4 years, with the association provided by the STAM being statistically significant over and above the B-ADL.Performance-based measures of IADL can predict progression to dementia over 4 years beyond that provided by an informant report of IADL. Performance-based IADL measures are promising tools for clinical practice to identify individuals at greater risk of developing dementia.
- Published
- 2022
23. Applying generalizability theory to examine assessments of subjective cognitive complaints: whose reports should we rely on - participant versus informant?
- Author
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Quoc Cuong Truong, Carol C Choo, Katya Numbers, Henry Brodaty, Oleg N. Medvedev, Valery L. Feigin, Nicole A. Kochan, Alexander Merkin, and Perminder S. Sachdev
- Subjects
Score ,03 medical and health sciences ,0302 clinical medicine ,Cognition ,Informant Questionnaire on Cognitive Decline in the Elderly ,medicine ,Dementia ,Humans ,Generalizability theory ,030212 general & internal medicine ,Reliability (statistics) ,Aged ,Aged, 80 and over ,Australia ,Measurement design ,Reproducibility of Results ,Mean age ,medicine.disease ,Psychiatry and Mental health ,Clinical Psychology ,Geriatrics and Gerontology ,Psychology ,Gerontology ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
Objectives:This study aimed to apply the generalizability theory (G-theory) to investigate dynamic and enduring patterns of subjective cognitive complaints (SCC), and reliability of two widely used SCC assessment tools.Design:G-theory was applied to assessment scales using longitudinal measurement design with five assessments spanning 10 years of follow-up.Setting:Community-dwelling older adults aged 70–90 years and their informants, living in Sydney, Australia, participated in the longitudinal Sydney Memory and Ageing Study.Participants:The sample included 232 participants aged 70 years and older, and 232 associated informants. Participants were predominantly White Europeans (97.8%). The sample of informants included 76 males (32.8%), 153 females (65.9%), and their age ranged from 27 to 86 years, with a mean age of 61.3 years (SD = 14.38).Measurements:The Memory Complaint Questionnaire (MAC-Q) and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE).Results:The IQCODE demonstrated strong reliability in measuring enduring patterns of SCC with G = 0.86. Marginally acceptable reliability of the 6-item MAC-Q (G = 0.77–0.80) was optimized by removing one item resulting in G = 0.80–0.81. Most items of both assessments were measuring enduring SCC with exception of one dynamic MAC-Q item. The IQCODE significantly predicted global cognition scores and risk of dementia incident across all occasions, while MAC-Q scores were only significant predictors on some occasions.Conclusions:While both informants’ (IQCODE) and self-reported (MAC-Q) SCC scores were generalizable across sample population and occasions, self-reported (MAC-Q) scores may be less accurate in predicting cognitive ability and diagnosis of each individual.
- Published
- 2021
24. The influence of rs53576 polymorphism in the oxytocin receptor (
- Author
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Russell J, Chander, Karen A, Mather, Rhiagh, Cleary, Sarah A, Grainger, Anbupalam, Thalamuthu, Katya, Numbers, Nicole A, Kochan, Nicola J, Armstrong, Henry, Brodaty, Julie D, Henry, and Perminder S, Sachdev
- Subjects
Adult ,Aged, 80 and over ,Young Adult ,Adolescent ,Genotype ,Receptors, Oxytocin ,Ethnicity ,Humans ,Empathy ,Middle Aged ,Aged - Abstract
Empathy is essential for navigating complex social environments. Prior work has shown associations between rs53576, a single nucleotide polymorphism (SNP) located in the oxytocin receptor gene (
- Published
- 2021
25. Increased reporting of subjective cognitive complaints over time predicts cognitive decline and incident dementia
- Author
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Ben C. P. Lam, John D. Crawford, Nicole A. Kochan, Perminder S. Sachdev, Katya Numbers, and Henry Brodaty
- Subjects
Male ,Aging ,media_common.quotation_subject ,Neuropsychological Tests ,Cognition ,medicine ,Personality ,Dementia ,Humans ,Cognitive Dysfunction ,Cognitive decline ,Risk factor ,skin and connective tissue diseases ,neoplasms ,media_common ,Aged ,Proportional hazards model ,business.industry ,Hazard ratio ,medicine.disease ,stomatognathic diseases ,Psychiatry and Mental health ,Mood ,Female ,Geriatrics and Gerontology ,business ,Clinical psychology - Abstract
Background Subjective cognitive complaints (SCCs) are a risk factor for dementia; however, little is known about their trajectories. Method Participants were 873 older adults (mage = 78.65 years; 55% females) from the Sydney Memory and Ageing Study that were followed-up biennially. SCCs were measured using the six-item Memory Complaint Questionnaire. Associations between initial level of SCC reporting, linear change in SCC reporting, and change in global cognition over 6 years was examined using latent growth curve analysis. Risk of dementia was examined over 10 years using Cox regression. Results After controlling for demographics, mood and personality, results revealed a negative longitudinal association between the slope of SCCs and the slope of global cognition scores (b = -0.01, p = 0.005, β = -0.44), such that participants who reported increasing SCCs showed a steeper rate of decline in global cognition over 6 years. Cox regression also revealed participants who reported increasing SCCs had a nearly fourfold increased risk of developing dementia over 10 years (hazard ratio 3.70, 1.24-11.01). Conclusion This study explored whether initial levels of, and change in, SCCs over time are associated with both cognitive decline and risk of dementia. These findings are clinically relevant as GPs should note patients reporting increasing SCCs as they may be at greater risk of cognitive decline and incident dementia.
- Published
- 2021
26. Social cognitive abilities in older adults with mild cognitive impairment and dementia
- Author
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Julie D. Henry, Henry Brodaty, Sarah A. Grainger, Rhiagh Cleary, Perminder S. Sachdev, Karen A. Mather, Katya Numbers, Debjani Das, Nicole A. Kochan, and Russell J. Chander
- Subjects
Epidemiology ,Health Policy ,medicine.disease ,Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,Developmental Neuroscience ,medicine ,Dementia ,Neurology (clinical) ,Geriatrics and Gerontology ,Psychology ,Cognitive impairment ,Social cognitive theory ,Clinical psychology - Published
- 2020
27. The latent construct of dementia phenotype: Validation and longitudinal examination in the Sydney Memory and Ageing Study
- Author
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Nicole A. Kochan, Julian N. Trollor, Brian Draper, Darren M. Lipnicki, Perminder S. Sachdev, Ben Cp Lam, John D. Crawford, Henry Brodaty, and Katya Numbers
- Subjects
Gerontology ,Epidemiology ,Health Policy ,medicine.disease ,Phenotype ,Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,Developmental Neuroscience ,Ageing ,medicine ,Dementia ,Neurology (clinical) ,Geriatrics and Gerontology ,Construct (philosophy) ,Psychology - Published
- 2020
28. Patterns of change in subjective cognitive complaints are associated with cognitive decline and dementia risk: Findings from the Sydney Memory and Ageing Study
- Author
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John D. Crawford, Henry Brodaty, Katya Numbers, Nicole A. Kochan, Ben C. P. Lam, and Perminder S. Sachdev
- Subjects
Epidemiology ,Health Policy ,Neuropsychology ,Cognition ,medicine.disease ,Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,Developmental Neuroscience ,Ageing ,medicine ,Dementia ,Neurology (clinical) ,Geriatrics and Gerontology ,Cognitive decline ,Psychology ,Clinical psychology - Published
- 2020
29. Development of a short-form version of the Reading the Mind in the Eyes Test for assessing theory of mind in older adults
- Author
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Karen A. Mather, Nicole A. Kochan, Perminder S. Sachdev, Rhiagh Cleary, Katya Numbers, Russell J. Chander, Sarah A. Grainger, John D. Crawford, Henry Brodaty, and Julie D. Henry
- Subjects
Aged, 80 and over ,Aging ,030214 geriatrics ,Receiver operating characteristic ,Theory of Mind ,Cognition ,Test (assessment) ,03 medical and health sciences ,Psychiatry and Mental health ,0302 clinical medicine ,Cross-Sectional Studies ,Social cognition ,Memory ,Theory of mind ,Surveys and Questionnaires ,Cohort ,Predictive power ,Humans ,Observational study ,Geriatrics and Gerontology ,10. No inequality ,Psychology ,Clinical psychology ,Aged - Abstract
Background: The Reading the Mind in the Eyes test (RMET) is a 36-item assessment for theory of mind (ToM) performance. While this measure has been shown to be sensitive to age-related ToM difficulties, there are no established cutoffs or guidelines currently available that are specific to older adults. This article seeks to validate a short-form version of the RMET appropriate for use in such populations. Methods: Cross-sectional data from 295 participants (mean age 86 years) from the Sydney Memory and Ageing Study, a longitudinal community observational cohort. Participants underwent an assessment battery that included the RMET. Individuals who scored >1SD below the RMET scores of cognitively normal participants were deemed to have below average RMET scores. Various model-building methods were used to generate short-form solutions of the RMET, which were compared with previously validated versions in their predictive power for below average full RMET performance. Results: Individuals with below average RMET performance tended to be older and have poorer global cognition. Of the eight short-form solutions, the 21-item version generated using genetic algorithm exhibited the best classification performance with an area under the receiver operating curve (AUROC) of 0.98 and had 93.2% accuracy in classifying individuals with below average ToM. A shorter 10-item solution derived by ant colony optimization also had acceptable performance. Conclusion: We recommend the 21-item version of the RMET for use in older adult populations for identifying individuals with impaired ToM. Where an even shorter version is needed with a trade-off of slightly reduced performance, the 10-item version is acceptable.
- Published
- 2020
30. Ageing stereotypes influence the transmission of false memories in the social contagion paradigm
- Author
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Celia B. Harris, Amanda J. Barnier, Katya Numbers, and Michelle L. Meade
- Subjects
Adult ,Male ,Background information ,Social memory ,media_common.quotation_subject ,Repression, Psychology ,Stereotype ,Emotional contagion ,False memory ,050105 experimental psychology ,law.invention ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Arts and Humanities (miscellaneous) ,Memory ,law ,Humans ,0501 psychology and cognitive sciences ,Social Behavior ,General Psychology ,media_common ,Stereotyping ,05 social sciences ,Age Factors ,nutritional and metabolic diseases ,Transmission (mechanics) ,Ageing ,Mental Recall ,Female ,Psychology ,Social psychology ,030217 neurology & neurosurgery - Abstract
These experiments are the first to investigate the impact of confederate accuracy, age, and age stereotypes in the social contagion of memory paradigm. Across two experiments, younger participants recalled household scenes with an actual (Experiment 1) or virtual (Experiment 2), older or younger confederate who suggested different proportions (0%, 33% or 100%) of false items during collaboration. In Experiment 2, positive and negative age stereotypes were primed by providing bogus background information about our older confederate before collaboration. Across both experiments, if confederates suggested false items participants readily incorporated these into their own memory reports. In Experiment 1, when no age stereotype was primed, participants adopted similar proportions of false items from younger and older confederates. Importantly, in Experiment 2, when our older confederate was presented in terms of negative ageing stereotypes, participants reported less false items and were better able to correctly identify the source of those false items.
- Published
- 2018
31. The effects of the COVID-19 pandemic on people with dementia
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Henry Brodaty and Katya Numbers
- Subjects
medicine.medical_specialty ,2019-20 coronavirus outbreak ,Coronavirus disease 2019 (COVID-19) ,Clinical Neurology ,MEDLINE ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Pandemic ,Epidemiology ,medicine ,Humans ,Dementia ,030212 general & internal medicine ,Year in Review ,Social isolation ,Psychiatry ,SARS-CoV-2 ,business.industry ,COVID-19 ,Alzheimer's disease ,medicine.disease ,Neurology (clinical) ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
The COVID-19 pandemic has posed unique risks to people with Alzheimer disease and dementia. Research from 2020 has shown that these people have a relatively high risk of contracting severe COVID-19, and are also at risk of neuropsychiatric disturbances as a result of lockdown measures and social isolation., Key advances People with dementia are at high risk of SARS-CoV-2 infection because cognitive symptoms cause difficulty with following safeguarding procedures and living arrangements in care homes facilitate viral spread1.Once infected, older adults with dementia are more likely to experience severe virus-related outcomes, including death, than are people without dementia4.A homozygous APOE ε4 genotype is associated with an increased risk of hospitalization for COVID-19 (ref.8), possibly owing to exacerbated inflammation and cytokine production that leads to a cytokine storm.Older adults with dementia, especially those in care homes, are at high risk of worsening psychiatric symptoms and severe behavioural disturbances as a result of social isolation during the pandemic3.
- Published
- 2021
32. O1‐02‐04: FAILURE TO IDENTIFY PARTICULAR ODOURS PREDICTS FUTURE DEMENTIA AND MORTALITY
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Katya Numbers, Julian N. Trollor, Henry Brodaty, Nicole A. Kochan, Darren M. Lipnicki, John D. Crawford, Kristan Kang, and Perminder S. Sachdev
- Subjects
Gerontology ,Psychiatry and Mental health ,Cellular and Molecular Neuroscience ,Developmental Neuroscience ,Epidemiology ,business.industry ,Health Policy ,medicine ,Dementia ,Neurology (clinical) ,Geriatrics and Gerontology ,medicine.disease ,business - Published
- 2019
33. The influences of partner accuracy and partner memory ability on social false memories
- Author
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Vladimir A. Perga, Katya Numbers, and Michelle L. Meade
- Subjects
Adult ,Collaborative memory ,Recall ,Poor memory ,Aptitude ,Experimental and Cognitive Psychology ,Emotional contagion ,False memory ,Test (assessment) ,Task (project management) ,Young Adult ,Neuropsychology and Physiological Psychology ,Arts and Humanities (miscellaneous) ,Memory task ,Mental Recall ,Humans ,Interpersonal Relations ,Cooperative Behavior ,Psychology ,Social psychology - Abstract
In this study, we examined whether increasing the proportion of false information suggested by a confederate would influence the magnitude of socially introduced false memories in the social contagion paradigm Roediger, Meade, & Bergman (Psychonomic Bulletin & Review 8:365–371, 2001). One participant and one confederate collaboratively recalled items from previously studied household scenes. During collaboration, the confederate interjected 0 %, 33 %, 66 %, or 100 % false items. On subsequent individual-recall tests across three experiments, participants were just as likely to incorporate misleading suggestions from a partner who was mostly accurate (33 % incorrect) as they were from a partner who was not at all accurate (100 % incorrect). Even when participants witnessed firsthand that their partner had a very poor memory on a related memory task, they were still as likely to incorporate the confederate’s entirely misleading suggestions on subsequent recall and recognition tests (Exp. 2). Only when participants witnessed firsthand that their partner had a very poor memory on a practice test of the experimental task itself were they able to reduce false memory, and this reduction occurred selectively on a subsequent individual recognition test (Exp. 3). These data demonstrate that participants do not always consider their partners’ memory ability when working on collaborative memory tasks.
- Published
- 2014
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