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HIV-associated neurocognitive disorders (HAND) are highly prevalent in those ageing with HIV. High-income country data suggest that vascular risk factors (VRFs) may be stronger predictors of HAND than HIV-disease severity, but data from sub-Saharan Africa are lacking. We evaluated relationships of VRFs, vascular end-organ damage and HAND in individuals aged ≥ 50 in Tanzania. c-ART-treated individuals were assessed for HAND using consensus criteria. The prevalence of VRFs and end organ damage markers were measured. The independent associations of VRFs, end organ damage and HAND were examined using multivariable logistic regression. Data were available for 153 individuals (median age 56, 67.3% female). HAND was highly prevalent (66.7%, 25.5% symptomatic) despite well-managed HIV (70.5% virally suppressed). Vascular risk factors included hypertension (34%), obesity (10.5%), hypercholesterolemia (33.3%), diabetes (5.3%) and current smoking (4.6%). End organ damage prevalence ranged from 1.3% (prior myocardial infarction) to 12.5% (left ventricular hypertrophy). Measured VRFs and end organ damage were not independently associated with HAND. The only significant association was lower diastolic BP (p 0.030, OR 0.969 (0.943-0.997). Our results suggest that vascular risk factors are not major drivers of HAND in this setting. Further studies should explore alternative aetiologies such as chronic inflammation.
Subject(s)
HIV Infections , Humans , Female , Male , Tanzania/epidemiology , Middle Aged , Risk Factors , HIV Infections/complications , HIV Infections/epidemiology , Aged , Prevalence , AIDS Dementia Complex/epidemiology , Anti-HIV Agents/therapeutic use , Antiretroviral Therapy, Highly Active , Neurocognitive Disorders/epidemiology , Neurocognitive Disorders/etiologyABSTRACT
OBJECTIVE: Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) prevalence is expected to increase in East Africa as treatment coverage increases, survival improves, and this population ages. This study aimed to better understand the current cognitive phenotype of this newly emergent population of older combination antiretroviral therapy (cART)-treated people living with HIV (PLWH), in which current screening measures lack accuracy. This will facilitate the refinement of HAND cognitive screening tools for this setting. METHOD: This is a secondary analysis of 253 PLWH aged ≥50 years receiving standard government HIV clinic follow-up in Kilimanjaro, Tanzania. They were evaluated with a detailed locally normed low-literacy neuropsychological battery annually on three occasions and a consensus panel diagnosis of HAND by Frascati criteria based on clinical evaluation and collateral history. RESULTS: Tests of verbal learning and memory, categorical verbal fluency, visual memory, and visuoconstruction had an area under the receiver operating characteristic curve >0.7 for symptomatic HAND (s-HAND) (0.70-0.72; p < 0.001 for all tests). Tests of visual memory, verbal learning with delayed recall and recognition memory, psychomotor speed, language comprehension, and categorical verbal fluency were independently associated with s-HAND in a logistic mixed effects model (p < 0.01 for all). Neuropsychological impairments varied by educational background. CONCLUSIONS: A broad range of cognitive domains are affected in older, well-controlled, East African PLWH, including those not captured in widely used screening measures. It is possible that educational background affects the observed cognitive impairments in this setting. Future screening measures for similar populations should consider assessment of visual memory, verbal learning, language comprehension, and executive and motor function.
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Background: The current cognitive tests have been developed based on and standardized against Western constructs and normative data. With older people of minority ethnic background increasing across Western countries, there is a need for cognitive screening tests to address factors which influence performance bias and timely diagnostic dementia accuracy. The diagnostic accuracy in translated and culturally adapted cognitive screening tests and their impact on test performance in diverse populations have not been well addressed to date. Objective: This review aims to highlight considerations relating to the adaptation processes, language, cultural influences, impact of immigration, and level of education to assess for dementia in non-Western and/or non-English speaking populations. Methods: We conducted a systematic search for studies addressing the effects of translation and cultural adaptations of cognitive screening tests (developed in a Western context) upon their diagnostic accuracy and test performance across diverse populations. Four electronic databases and manual searches were conducted, using a predefined search strategy. A narrative synthesis of findings was conducted. Results: Search strategy yielded 2,890 articles, and seventeen studies (4,463 participants) met the inclusion criteria. There was variability in the sensitivity and specificity of cognitive tests, irrespective of whether they were translated only, culturally adapted only, or both. Cognitive test performance was affected by education, linguistic ability, and aspects of acculturation. Conclusions: We highlight the importance of translating and culturally adapting tests that have been developed in the Western context. However, these findings should be interpreted with caution as results varied due to the broad selection of included cognitive tests.
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INTRODUCTION: In Alzheimer's disease (AD), early diagnosis facilitates treatment options and leads to beneficial outcomes for patients, their carers and the healthcare system. The neuropsychological battery of the Uniform Data Set (UDSNB3.0) assesses cognition in ageing and dementia, by measuring scores across different cognitive domains such as attention, memory, processing speed, executive function and language. However, its neuroanatomical correlates have not been investigated using 7 Tesla MRI (7T MRI). METHODS: We used 7T MRI to investigate the correlations between hippocampal subfield volumes and the UDSNB3.0 in 24 individuals with Amyloidß-status AD and 18 age-matched controls, with respective age ranges of 60 (42-76) and 62 (52-79) years. AD participants with a Medial Temporal Atrophy scale of higher than 2 on 3T MRI were excluded from the study. RESULTS: A significant difference in the entire hippocampal volume was observed in the AD group compared to healthy controls (HC), primarily influenced by CA1, the largest hippocampal subfield. Notably, no significant difference in whole brain volume between the groups implied that hippocampal volume loss was not merely reflective of overall brain atrophy. UDSNB3.0 cognitive scores showed significant differences between AD and HC, particularly in Memory, Language, and Visuospatial domains. The volume of the Dentate Gyrus (DG) showed a significant association with the Memory and Executive domain scores in AD patients as assessed by the UDSNB3.0.. The data also suggested a non-significant trend for CA1 volume associated with UDSNB3.0 Memory, Executive, and Language domain scores in AD. In a reassessment focusing on hippocampal subfields and MoCA memory subdomains in AD, associations were observed between the DG and Cued, Uncued, and Recognition Memory subscores, whereas CA1 and Tail showed associations only with Cued memory. DISCUSSION: This study reveals differences in the hippocampal volumes measured using 7T MRI, between individuals with early symptomatic AD compared with healthy controls. This highlights the potential of 7T MRI as a valuable tool for early AD diagnosis and the real-time monitoring of AD progression and treatment efficacy. CLINICALTRIALS: GOV: ID NCT04992975 (Clinicaltrial.gov 2023).
Subject(s)
Alzheimer Disease , CA1 Region, Hippocampal , Dentate Gyrus , Magnetic Resonance Imaging , Memory Disorders , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/pathology , Male , Magnetic Resonance Imaging/methods , Female , Aged , Dentate Gyrus/diagnostic imaging , Dentate Gyrus/pathology , Middle Aged , CA1 Region, Hippocampal/diagnostic imaging , CA1 Region, Hippocampal/pathology , Memory Disorders/diagnostic imaging , Memory Disorders/pathology , Adult , Amyloid beta-Peptides/metabolismABSTRACT
Background: Cognitive screening tools are important in the detection of dementia, including Alzheimer's disease; however, they may contain cultural biases. Objective: This review examines culture-fair cognitive screening tools and evaluates their screening accuracy, strengths, and limitations. Methods: Medline, Embase, PsychINFO and CINAHL were searched. The protocol was registered on PROSPERO (CRD42021288776). Included studies used a culture-fair tool to assess cognition in older adults from varying ethnicities. Narrative synthesis was conducted. Results: 28 studies were included assessing eleven different tools. The Rowland Universal Dementia Assessment Scale (RUDAS) was as accurate as the Mini-Mental State Examination (MMSE) (AUC 0.62-0.93), with a similar sensitivity (52-94%) and better specificity (70-98%), and the Multicultural Cognitive Examination (MCE) had improved screening accuracy (AUC 0.99) compared to RUDAS (AUC 0.92). The Visual Cognitive Assessment Test (VCAT) was equivalent to MMSE (AUC 0.84-0.91). The Kimberley Indigenous Cognitive Assessment tool (KICA) had AUC of 0.93-0.95; sensitivity of 90.6%, specificity 92.6%. Conclusions: The RUDAS, KICA and VCAT were superior to MMSE for screening dementia in ethnic minorities. Other tools also showed good screening accuracy. Further research should be done to validate tools in different populations.
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PURPOSE OF REVIEW: We reviewed recent literature on prevalence and interventional approaches for cognitive impairment in the context of HIV infection alongside current controversies and challenges around its nomenclature, screening, and diagnosis. RECENT FINDINGS: Prevalence estimates for HIV-associated neurocognitive disorder (HAND) indicate that HAND remains highly prevalent despite combination antiretroviral treatment (cART) widely used. The available data are heterogeneous, particularly in sub-Saharan Africa (SSA) where recent reviews indicate substantial heterogeneity, wide prevalence estimates and lack of data from the majority SSA countries, despite them currently experiencing the greatest burden worldwide of both HIV and HAND.Several alternative approaches to diagnosis and classification of cognitive impairment in HIV have been published, taking into account changing clinical phenotypes. SUMMARY: Cognitive impairment remains a significant challenge in the care of people living with HIV despite advances in treatment. Ongoing controversies exist around nomenclature and classification, screening measures, and the phenotype and aetiology of observed impairments. Two current areas of research priority and focus include understanding current phenotypes of individuals living and ageing with treated HIV and differing levels of risk for HAND in these phenotypes, alongside the effects of commonly occurring comorbidities.The current evidence base for interventional approaches is limited, but growing. The most promising avenues appear to be multidisciplinary. These are currently focussed on high income settings rather than SSA where the majority of people living with HIV, and affected by cognitive impairment in the context of HIV, currently reside.
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Cognitive Dysfunction , HIV Infections , Humans , Aged , HIV Infections/complications , HIV Infections/epidemiology , HIV Infections/drug therapy , HIV , Neurocognitive Disorders/diagnosis , Neurocognitive Disorders/epidemiology , Neurocognitive Disorders/etiology , Cognitive Dysfunction/complications , Africa South of the Sahara/epidemiologyABSTRACT
OBJECTIVE: In sub-Saharan Africa, there are no validated screening tools for delirium in older adults, despite the known vulnerability of older people to delirium and the associated adverse outcomes. This study aimed to assess the effectiveness of a brief smartphone-based assessment of arousal and attention (DelApp) in the identification of delirium amongst older adults admitted to the medical department of a tertiary referral hospital in Northern Tanzania. METHOD: Consecutive admissions were screened using the DelApp during a larger study of delirium prevalence and risk factors. All participants subsequently underwent detailed clinical assessment for delirium by a research doctor. Delirium and dementia were identified against DSM-5 criteria by consensus. RESULTS: Complete data for 66 individuals were collected of whom 15 (22.7%) had delirium, 24.5% had dementia without delirium, and 10.6% had delirium superimposed on dementia. Sensitivity and specificity of the DelApp for delirium were 0.87 and 0.62, respectively (AUROC 0.77) and 0.88 and 0.73 (AUROC 0.85) for major cognitive impairment (dementia and delirium combined). Lower DelApp score was associated with age, significant visual impairment (<6/60 acuity), illness severity, reduced arousal and DSM-5 delirium on univariable analysis, but on multivariable logistic regression only arousal remained significant. CONCLUSION: In this setting, the DelApp performed well in identifying delirium and major cognitive impairment but did not differentiate delirium and dementia. Performance is likely to have been affected by confounders including uncorrected visual impairment and reduced level of arousal without delirium. Negative predictive value was nevertheless high, indicating excellent 'rule out' value in this setting.
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CONTEXT: Loss of a child to a life-limiting condition (LLC) is 1 of the most traumatic life events for parents. Research focusing on fathers' experiences is in its infancy. OBJECTIVES: Using a meta-ethnographic approach, we systematically reviewed the literature around fathers' predeath and postdeath experiences of loss and grief. DATA SOURCES: We searched Medline, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Science Direct, and used the meta-ethnography reporting guidelines; the Preferred Reporting Items for Systematic Reviews and Meta-Analyses; and sampling strategy, type of study, approaches, range of years, limits, inclusion and exclusions, terms used, and electronic sources recommendations. STUDY SELECTION: We used the Guide to Children's Palliative Care and the directory of LLCs to select qualitative articles published up until the end of March 2023 that described fathers' predeath and postdeath experiences of loss and grief after their child's LLC. We excluded studies that failed to differentiate outcomes between mothers and fathers. DATA EXTRACTION: Extracted data included study details, participants' characteristics, response rate, source of participants, method and time of data collection, children's characteristics, and quality assessment. First-order and second-order data were also extracted. RESULTS: Forty studies informed a FATHER model of loss and grief. This highlights both similarities (ambivalence, trauma responses, fatigue, anxiety, unresolved grief, guilt) and distinct features defining the predeath and postdeath experiences of loss and grief. LIMITATIONS: There was a bias toward greater mother participation in research. Specific categories of fathers remain underrepresented in palliative care literature. CONCLUSIONS: Many fathers experience disenfranchised grief and deterioration in mental health after a child's diagnosis and postdeath. Our model opens possibilities for personalized clinical support in the palliative care system for fathers.
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Fathers , Grief , Male , Female , Humans , Child , Fathers/psychology , Parents , Mothers/psychology , Father-Child RelationsABSTRACT
Studies of depression and its outcomes in older people living with HIV (PLWH) are currently lacking in sub-Saharan Africa. This study aims to investigate the prevalence of psychiatric disorders in PLWH aged ≥ 50 years in Tanzania focussing on prevalence and 2-year outcomes of depression. PLWH aged ≥ 50 were systematically recruited from an outpatient clinic and assessed using the Mini-International Neuropsychiatric Interview (MINI). Neurological and functional impairment was assessed at year 2 follow-up. At baseline, 253 PLWH were recruited (72.3% female, median age 57, 95.5% on cART). DSM-IV depression was highly prevalent (20.9%), whereas other DSM-IV psychiatric disorders were uncommon. At follow-up (n = 162), incident cases of DSM-IV depression decreased from14.2 to 11.1% (χ2: 2.48, p = 0.29); this decline was not significant. Baseline depression was associated with increased functional and neurological impairment. At follow-up, depression was associated with negative life events (p = 0.001), neurological impairment (p < 0.001), and increased functional impairment (p = 0.018), but not with HIV and sociodemographic factors. In this setting, depression appears highly prevalent and associated with poorer neurological and functional outcomes and negative life events. Depression may be a future intervention target.
Subject(s)
HIV Infections , Humans , Adult , Female , Aged , Male , Longitudinal Studies , HIV Infections/complications , HIV Infections/epidemiology , HIV Infections/psychology , Depression/epidemiology , Prevalence , Tanzania/epidemiologyABSTRACT
Environmental motion can induce physiological stress and trigger motion sickness. In these situations, lower-than-normal levels of adrenocorticotropic hormone (ACTH) have been linked with increased susceptibility to motion sickness in healthy individuals. However, whether patients with primary adrenal insufficiency, who typically have altered ACTH levels compared to the normal population, exhibit alterations in sickness susceptibility remains unknown. To address this, we recruited 78 patients with primary adrenal insufficiency and compared changes in the motion sickness susceptibility scores from 10 years prior to diagnosis (i.e. retrospective sickness rating) with the current sickness measures (post-diagnosis), using the validated motion sickness susceptibility questionnaire (MSSQ). Group analysis revealed that motion sickness susceptibility pre-diagnosis did not differ between controls and patients. We observed that following treatment, current measures of motion sickness were significantly increased in patients and subsequent analysis revealed that this increase was primarily in female patients with primary adrenal insufficiency. These observations corroborate the role of stress hormones in modulating sickness susceptibility and support the notion of a sexually dimorphic adrenal cortex as we only observed selective enhancement in females. A potential mechanism to account for our novel observation remains obscure, but we speculate that it may reflect a complex sex-disease-drug interaction.
Subject(s)
Addison Disease , Motion Sickness , Humans , Female , Sex Characteristics , Retrospective Studies , Motion Sickness/etiology , Adrenocorticotropic HormoneABSTRACT
Background: The emergence of COVID-19 was rapidly followed by infection and the deaths of millions of people across the globe. With much of the research and scientific advancement rightly focused on reducing the burden of severe and critical acute COVID-19 infection, the long-term effects endured by those who survived the acute infection has been previously overlooked. Now, an appreciation for the post-COVID-19 condition, including its neurological manifestations, is growing, although there remain many unknowns regarding the etiology and risk factors of the condition, as well as how to effectively diagnose and treat it. Methods: Here, drawing upon the experiences and expertise of the clinicians and academics of the European working group on COVID-19, we have reviewed the current literature to provide a comprehensive overview of the neurological sequalae of the post-COVID-19 condition. Results: In this review, we provide a summary of the neurological symptoms associated with the post-COVID-19 condition, before discussing the possible mechanisms which may underly and manifest these symptoms. Following this, we explore the risk factors for developing neurological symptoms as a result of COVID-19 and the post-COVID-19 condition, as well as how COVID-19 infection may itself be a risk factor for the development of neurological disease in the future. Lastly, we evaluate how the post-COVID condition could be accurately diagnosed and effectively treated, including examples of the current guidelines, clinical outcomes, and tools that have been developed to aid in this process, as well as addressing the protection provided by COVID-19 vaccines against the post-COVID-19 condition. Conclusions: Overall, this review provides a comprehensive overview of the neurological sequalae of the post-COVID-19 condition. Impact statement With our understanding of the neurological complications of the post-COVID-19 condition currently lacking sufficient depth, this review aimed at highlighting the current knowns and unknowns of the post-COVID-19 condition. In this review, we draw upon the experiences and expertise of the clinicians and academics of the European working group on COVID-19, as well as explore the current published literature, to evaluate a range of topics associated with the neurological complications of the post-COVID-19 condition. As a result, we have provided a comprehensive review of the topic. The European Working Group on SARS-CoV-2 Many essential questions surrounding COVID-19 remain unanswered, including its neurological complications and associated sequalae. In this review, we aim at identifying the current gaps in our understanding of post-COVID-19 neurological sequalae and suggest how future studies should be undertaken to fill these gaps. This review will draw upon the current biological and mechanistic understanding of COVID-19 and post-COVID-19 complications to discuss the clinically relevant aspects associated with the neurological manifestations of post-COVID-19 syndrome. From our discussions, the following questions were considered highly relevant for contemplation.
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COVID-19 , Nervous System Diseases , Humans , COVID-19/complications , SARS-CoV-2 , COVID-19 Vaccines , Post-Acute COVID-19 Syndrome , Magnetic Resonance Imaging , Brain , Nervous System Diseases/epidemiology , Nervous System Diseases/etiologyABSTRACT
BACKGROUND: The incidence of dementia in Black and Asian populations in the UK is set to rise. There is concern surrounding differences in services provided for different ethnic groups. OBJECTIVE: This study aimed to examine ethnic variations in survival, services accessed, and medication use across White, Black, and Asian groups in routine memory clinic setting. METHODS: We retrospectively examined referrals to a memory service between 2013 and 2021. A random sample of 104 White, 99 Asian, and 74 Black patients were analyzed for differences in support services, voluntary services, medication use, and survival rate. RESULTS: There were statistically significant differences in survival of the Asian compared to the White group (Hazard ratio (HRâ=â2.17,95% confidence interval (CI) 1.23-3.85, pâ=â0.008)) following adjustment for age, gender, diagnosis, cognitive impairment, severity, access to support and voluntary services, and use of cholinesterase inhibitors, N-methyl-D-aspartate antagonists, and antipsychotics. The Asian group showed a statistically significantly reduction in access to support services compared to the White group (HRâ=â0.05, 95% CI 0.01-0.37, pâ=â0.003). In contrast, the survival rate was similar between the White and Black dementia patients. CONCLUSION: We found significantly reduced survival and reduced access to support services in Asian compared to White patients with dementia. Further research is needed to investigate the generalizability of our results, and determine the cause, and consequent remedies of these associations in ethnic minority groups.
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Dementia , Ethnicity , Humans , Dementia/ethnology , Minority Groups , Retrospective Studies , White People , Memory , Asian People , Black People , Health Services Accessibility , Survival RateABSTRACT
OBJECTIVES: HIV-associated neurocognitive disorders (HANDs) are prevalent in older people living with HIV (PLWH) worldwide. HAND prevalence and incidence studies of the newly emergent population of combination antiretroviral therapy (cART)-treated older PLWH in sub-Saharan Africa are currently lacking. We aimed to estimate HAND prevalence and incidence using robust measures in stable, cART-treated older adults under long-term follow-up in Tanzania and report cognitive comorbidities. DESIGN: Longitudinal study. PARTICIPANTS: A systematic sample of consenting HIV-positive adults aged ≥50 years attending routine clinical care at an HIV Care and Treatment Centre during March-May 2016 and followed up March-May 2017. MEASUREMENTS: HAND by consensus panel Frascati criteria based on detailed locally normed low-literacy neuropsychological battery, structured neuropsychiatric clinical assessment, and collateral history. Demographic and etiological factors by self-report and clinical records. RESULTS: In this cohort (n = 253, 72.3% female, median age 57), HAND prevalence was 47.0% (95% CI 40.9-53.2, n = 119) despite well-managed HIV disease (Mn CD4 516 (98-1719), 95.5% on cART). Of these, 64 (25.3%) were asymptomatic neurocognitive impairment, 46 (18.2%) mild neurocognitive disorder, and 9 (3.6%) HIV-associated dementia. One-year incidence was high (37.2%, 95% CI 25.9 to 51.8), but some reversibility (17.6%, 95% CI 10.0-28.6 n = 16) was observed. CONCLUSIONS: HAND appear highly prevalent in older PLWH in this setting, where demographic profile differs markedly to high-income cohorts, and comorbidities are frequent. Incidence and reversibility also appear high. Future studies should focus on etiologies and potentially reversible factors in this setting.
Subject(s)
AIDS Dementia Complex , HIV Infections , Humans , Female , Aged , Male , HIV , Incidence , Prevalence , Longitudinal Studies , Tanzania/epidemiology , Cross-Sectional Studies , HIV Infections/complications , HIV Infections/drug therapy , HIV Infections/epidemiology , AIDS Dementia Complex/epidemiology , Neurocognitive Disorders/diagnosis , Neurocognitive Disorders/epidemiology , Neuropsychological TestsABSTRACT
Introduction: Coronavirus disease 2019 (COVID-19) has caused >3.5 million deaths worldwide and affected >160 million people. At least twice as many have been infected but remained asymptomatic or minimally symptomatic. COVID-19 includes central nervous system manifestations mediated by inflammation and cerebrovascular, anoxic, and/or viral neurotoxicity mechanisms. More than one third of patients with COVID-19 develop neurologic problems during the acute phase of the illness, including loss of sense of smell or taste, seizures, and stroke. Damage or functional changes to the brain may result in chronic sequelae. The risk of incident cognitive and neuropsychiatric complications appears independent from the severity of the original pulmonary illness. It behooves the scientific and medical community to attempt to understand the molecular and/or systemic factors linking COVID-19 to neurologic illness, both short and long term. Methods: This article describes what is known so far in terms of links among COVID-19, the brain, neurological symptoms, and Alzheimer's disease (AD) and related dementias. We focus on risk factors and possible molecular, inflammatory, and viral mechanisms underlying neurological injury. We also provide a comprehensive description of the Alzheimer's Association Consortium on Chronic Neuropsychiatric Sequelae of SARS-CoV-2 infection (CNS SC2) harmonized methodology to address these questions using a worldwide network of researchers and institutions. Results: Successful harmonization of designs and methods was achieved through a consensus process initially fragmented by specific interest groups (epidemiology, clinical assessments, cognitive evaluation, biomarkers, and neuroimaging). Conclusions from subcommittees were presented to the whole group and discussed extensively. Presently data collection is ongoing at 19 sites in 12 countries representing Asia, Africa, the Americas, and Europe. Discussion: The Alzheimer's Association Global Consortium harmonized methodology is proposed as a model to study long-term neurocognitive sequelae of SARS-CoV-2 infection. Key Points: The following review describes what is known so far in terms of molecular and epidemiological links among COVID-19, the brain, neurological symptoms, and AD and related dementias (ADRD)The primary objective of this large-scale collaboration is to clarify the pathogenesis of ADRD and to advance our understanding of the impact of a neurotropic virus on the long-term risk of cognitive decline and other CNS sequelae. No available evidence supports the notion that cognitive impairment after SARS-CoV-2 infection is a form of dementia (ADRD or otherwise). The longitudinal methodologies espoused by the consortium are intended to provide data to answer this question as clearly as possible controlling for possible confounders. Our specific hypothesis is that SARS-CoV-2 triggers ADRD-like pathology following the extended olfactory cortical network (EOCN) in older individuals with specific genetic susceptibility.The proposed harmonization strategies and flexible study designs offer the possibility to include large samples of under-represented racial and ethnic groups, creating a rich set of harmonized cohorts for future studies of the pathophysiology, determinants, long-term consequences, and trends in cognitive aging, ADRD, and vascular disease.We provide a framework for current and future studies to be carried out within the Consortium. and offers a "green paper" to the research community with a very broad, global base of support, on tools suitable for low- and middle-income countries aimed to compare and combine future longitudinal data on the topic.The Consortium proposes a combination of design and statistical methods as a means of approaching causal inference of the COVID-19 neuropsychiatric sequelae. We expect that deep phenotyping of neuropsychiatric sequelae may provide a series of candidate syndromes with phenomenological and biological characterization that can be further explored. By generating high-quality harmonized data across sites we aim to capture both descriptive and, where possible, causal associations.
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BACKGROUND: Myeloperoxidase (MPO), a neutrophil-derived pro-inflammatory protein, co-localizes with amyloid-ß (Aß) plaques in Alzheimer's disease (AD). Anti-dementia treatment may facilitate efflux of Aß and associated plaque proteins from the brain to the peripheral circulation, therefore providing potential biomarkers for the monitoring of donor response to drug treatment. OBJECTIVE: We investigated the diagnostic utility of MPO as a biomarker of AD, and how anti-dementia treatment alters plasma MPO concentration. METHODS: Thirty-two AD patients were recruited, and plasma collected pre-drug administration (baseline), and 1- and 6-months post-treatment. All patients received cholinesterase inhibitors (ChEIs). At baseline and 6 months, patients underwent neuropsychological assessment. Forty-nine elderly healthy individuals with normal cognitive status served as controls. Plasma MPO concentration was measured by ELISA. RESULTS: AD drug naïve patients had similar plasma MPO concentration to their control counterparts (pâ>â0.05). Baseline MPO levels positively correlated with Neuropsychiatric Inventory score (râ=â0.5080; pâ=â0.011) and carer distress (râ=â0.5022; pâ=â0.012). Following 1-month ChEI treatment, 84.4% of AD patients exhibited increased plasma MPO levels (pâ<â0.001), which decreased at 6 months (pâ<â0.001). MPO concentration at 1 month was greatest in AD patients whose memory deteriorated during the study period (pâ=â0.028), and for AD patients with deterioration in Cornell assessment score (pâ=â0.044). CONCLUSION: Whereas baseline MPO levels did not differentiate between healthy and AD populations, baseline MPO positively correlated with initial Neuropsychiatric Inventory evaluation. Post-treatment, transient MPO upregulation in ChEI-treated patients may reflect worse therapeutic outcome. Further studies are required to assess the potential of plasma MPO as an AD therapeutic biomarker.
Subject(s)
Alzheimer Disease , Aged , Alzheimer Disease/psychology , Amyloid beta-Peptides , Biomarkers , Cholinesterase Inhibitors/therapeutic use , Humans , Peroxidase/therapeutic useABSTRACT
BACKGROUND: Cognitive training (CT) may be beneficial in delaying the onset or slowing dementia progression. CT has been evaluated quantitatively and qualitatively, but none have used mixed methods approaches. OBJECTIVE: The aim of this study was to use a mixed methods approach to identify those who may selectively benefit from CT. METHODS: This was an explanatory sequential mixed methods study involving a quantitative randomized trial of 12 weeks multi-domain CT in healthy older adults (HC, nâ=â20), and people living with mild cognitive impairment (MCI; nâ=â12) and dementia (nâ=â24). Quantitative outcomes included: cognition, mood, quality of life, and activities of daily living. 28 (10 HC, 6 MCI, 12 dementia) training participants completed semi-structured interviews with their carer. Quantitative and qualitative data were integrated using joint displays. RESULTS: Three participants dropped out from the training early-on, leaving 25 participants with follow-up data for full integration (10 HC, 6 MCI, 9 dementia). Dropouts and lower adherence to training were more common in dementia participants with greater non-modifiable barriers. High adherers were more resilient to negative emotions, and poorer or fluctuating performance. Integrated analysis found the majority of participants (nâ=â24) benefited across outcomes, with no clear profile of individuals who benefited more than others. Participants made a number of key recommendations to improve adherence and minimize dropout to CT. CONCLUSION: Reasons for dropout and low adherence were identified, with recommendations provided for the design of CT for dementia. An individual approach to training should be adopted and low adherence should not preclude engagement with CT.
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Cognitive Dysfunction , Dementia , Activities of Daily Living , Aged , Cognition , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/psychology , Cognitive Dysfunction/therapy , Dementia/diagnostic imaging , Dementia/psychology , Dementia/therapy , Feasibility Studies , Humans , Quality of Life , Randomized Controlled Trials as TopicABSTRACT
BACKGROUND: The differentiation of a preclinical or prodromal Alzheimer's disease (AD) is challenging particularly in patients with early onset Alzheimer's or related dementias (EOARD). We report our experience on diagnostic lumbar puncture to diagnose EOARD at a tertiary neurocognitive referral center in Nottingham, England from March 2018 to October 2020. OBJECTIVE: To assess amyloid-ß42 (Aß42), total tau, and Thr181-phosphorylated tau (p-tau) measurements in the cerebrospinal fluid (CSF) in patients with mild cognitive impairment (MCI) and in relation to their follow-up cognitive performance. METHODS: Thirty participants aged 32-68 years old (mean 59 years; 57% female) were included. Clinical diagnosis was based on clinical presentation, neurocognitive profile, neuroradiological features (MRI, FDG-PET CT) and CSF Aß42, total tau, and p-tau measurements. RESULTS: Patients with MCI who progressed to AD (prodromal AD) had significantly higher CSF total (797.63âpg/ml) and p-tau (82.31âpg/ml), and lower Aß42 levels (398.94âpg/ml) in comparison to their counterparts with stable MCI (total tau 303.67âpg/ml, p-tau 43.56âpg/ml, Aß42 873.44âpg/ml) (pâ<â0.01 for CSF total and p-tau measures and pâ<â0.0001 for CSF Aß42 measures). None of the CSF biomarkers correlated with any of the cognitive performance measures. Principal component analysis confirmed that the clinical diagnosis of MCI secondary to AD, namely prodromal AD (as per NIA-AA criteria) in younger adults, was associated with decreased CSF Aß42. CONCLUSION: In early onset AD, low levels of CSF Aß42 appear to be more sensitive than total and p-tau measures in differentiating AD MCI from other forms of dementia. Further work on larger samples of EOARD in clinical practice will address the cost effectiveness of making an earlier diagnosis.
Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Aged , Alzheimer Disease/diagnosis , Amyloid beta-Peptides/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Cognitive Dysfunction/cerebrospinal fluid , Cognitive Dysfunction/diagnostic imaging , Female , Humans , Male , Peptide Fragments/cerebrospinal fluid , tau Proteins/cerebrospinal fluidSubject(s)
Cognitive Dysfunction , Dementia , Cognition , Cognitive Dysfunction/diagnosis , Dementia/diagnosis , HumansABSTRACT
BACKGROUND: Cognitive decline is classically attributed to organic causes such as dementia; however, depression can play a role in cognitive decline. OBJECTIVE: To evaluate cognitive screening tools and the 4-item Geriatric Depression Scale (GDS-4) for use in primary care to distinguish cognitive decline secondary to depression. METHOD: Clinical data collected over 2.5 years for assessed patients in a secondary clinical service for younger adults. Cognitive screening tools (General Practitioner Assessment of Cognition, Addenbrooke's Cognitive Examination-III, Rowland Universal Dementia Assessment Scale, Salzburg Dementia Test Prediction) and GDS-4 were analyzed for their accuracy to differentiate patients with cognitive decline due to depression from those with subjective cognitive complaints. RESULTS: 180 young adults seen in a memory clinic setting (<â65 years) were included. These individuals either had a diagnosis of depression (nâ=â46) or no cognitive impairment on assessment (nâ=â134) despite having subjective cognitive complaints. All used cognitive tools had poor accuracy in differentiating cognitive decline secondary to depression from subjective cognitive complaints. The GDS-4 alone, however, was able to differentiate with high accuracy (AUCâ=â0.818) individuals who had cognitive problems secondary to depression. CONCLUSION: Cognitive screening tools used alone are ineffective in discriminating cognitive decline secondary to depression. Incorporating the GDS-4 into the screening process by primary practitioners could facilitate early identification and treatment of depression in younger people, avoiding unnecessary referrals memory services.