Cognitive domains affected post-COVID-19; a systematic review and meta-analysis.

BACKGROUND AND PURPOSE: This review aims to characterize the pattern of post-COVID-19 cognitive impairment, allowing better prediction of impact on daily function to inform clinical management and rehabilitation. METHODS: A systematic review and meta-analysis of neurocognitive sequelae following COVID-19 was conducted, following PRISMA-S guidelines. Studies were included if they reported domain-specific cognitive assessment in patients with COVID-19 at >4 weeks post-infection. Studies were deemed high-quality if they had >40 participants, utilized healthy controls, had low attrition rates and mitigated for confounders. RESULTS: Five of the seven primary Diagnostic and Statistical Manual of Mental Disorders (DSM-5) cognitive domains were assessed by enough high-quality studies to facilitate meta-analysis. Medium effect sizes indicating impairment in patients post-COVID-19 versus controls were seen across executive function (standardised mean difference (SMD) -0.45), learning and memory (SMD -0.55), complex attention (SMD -0.54) and language (SMD -0.54), with perceptual motor function appearing to be impacted to a greater degree (SMD -0.70). A narrative synthesis of the 56 low-quality studies also suggested no obvious pattern of impairment. CONCLUSIONS: This review found moderate impairments across multiple domains of cognition in patients post-COVID-19, with no specific pattern. The reported literature was significantly heterogeneous, with a wide variety of cognitive tasks, small sample sizes and disparate initial disease severities limiting interpretability. The finding of consistent impairment across a range of cognitive tasks suggests broad, as opposed to domain-specific, brain dysfunction. Future studies should utilize a harmonized test battery to facilitate inter-study comparisons, whilst also accounting for the interactions between COVID-19, neurological sequelae and mental health, the interplay between which might explain cognitive impairment.

Recent advances in HIV-associated neurocognitive disorders: a focus on older adults and sub-Saharan Africa.

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.

Current perspectives on prevention of vascular cognitive impairment and promotion of vascular brain health.

INTRODUCTION: The true global burden of vascular cognitive impairment (VCI) is unknown. Reducing risk factors for stroke and cardiovascular disease would inevitably curtail VCI. AREAS COVERED: The authors review current diagnosis, epidemiology, and risk factors for VCI. VCI increases in older age and by inheritance of known genetic traits. They emphasize modifiable risk factors identified by the 2020 Lancet Dementia Commission. The most profound risks for VCI also include lower education, cardiometabolic factors, and compromised cognitive reserve. Finally, they discuss pharmacological and non-pharmacological interventions. EXPERT OPINION: By virtue of the high frequencies of stroke and cardiovascular disease the global prevalence of VCI is expectedly higher than prevalent neurodegenerative disorders causing dementia. Since ~ 90% of the global burden of stroke can be attributed to modifiable risk factors, a formidable opportunity arises to reduce the burden of not only stroke but VCI outcomes including progression from mild to the major in form of vascular dementia. Strict control of vascular risk factors and secondary prevention of cerebrovascular disease via pharmacological interventions will impact on burden of VCI. Non-pharmacological measures by adopting healthy diets and encouraging physical and cognitive activities and urging multidomain approaches are important for prevention of VCI and preservation of vascular brain health.

Digital phenotyping: An equal opportunity approach to reducing disparities in Alzheimer's disease and related dementia research.

A rapidly aging world population is fueling a concomitant increase in Alzheimer's disease (AD) and related dementias (ADRD). Scientific inquiry, however, has largely focused on White populations in Australia, the European Union, and North America. As such, there is an incomplete understanding of AD in other populations. In this perspective, we describe research efforts and challenges of cohort studies from three regions of the world: Central America, East Africa, and East Asia. These cohorts are engaging with the Davos Alzheimer's Collaborative (DAC), a global partnership that brings together cohorts from around the world to advance understanding of AD. Each cohort is poised to leverage the widespread use of mobile devices to integrate digital phenotyping into current methodologies and mitigate the lack of representativeness in AD research of racial and ethnic minorities across the globe. In addition to methods that these three cohorts are already using, DAC has developed a digital phenotyping protocol that can collect ADRD-related data remotely via smartphone and/or in clinic via a tablet to generate a common data elements digital dataset that can be harmonized with additional clinical and molecular data being collected at each cohort site and when combined across cohorts and made accessible can provide a global data resource that is more racially/ethnically represented of the world population.

Preliminary evaluation of a smartphone application (DelApp) for identification of delirium in sub-Saharan Africa.

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.

The prevalence and outcomes of depression in older HIV-positive adults in Northern Tanzania: a longitudinal study.

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.

Correlates of Gait Speed Among Older Adults From 6 Countries: Findings From the COSMIC Collaboration.

BACKGROUND: Few studies have compared gait speed and its correlates among different ethnogeographic regions. The goals of this study were to describe usual and rapid gait speed, and identify their correlates across Australian, Asian, and African countries. METHODS: We used data from 6 population-based cohorts of adults aged 65+ from 6 countries and 3 continents (N = 6 472), with samples ranging from 231 to 1 913. All cohorts are members of the Cohort Studies of Memory in an International Consortium collaboration. We investigated whether clinical (body mass index [BMI], hypertension, stroke, apolipoprotein status), psychological (cognition, mood, general health), and behavioral factors (smoking, drinking, physical activity) correlated with usual (N = 4 cohorts) and rapid gait speed (N = 3 cohorts) similarly across cohorts. Regression models were controlled for age, sex, and education, and were sex-stratified. RESULTS: Age- and sex-standardized usual gait speed means ranged from 0.61 to 1.06 m/s and rapid gait speed means ranged from 1.16 to 1.64 m/s. Lower BMI and better cognitive function consistently correlated with faster gait speed in all cohorts. Less consistently, not having hypertension and greater physical activity engagement were associated with faster gait speed. Associations with mood, smoking, and drinking were largely nonsignificant. These patterns were not attenuated by demographics. There was limited evidence that the associations differed by sex, except physical activity, where the greater intensity was associated with usual gait among men but not women. CONCLUSIONS: This study is among the first to describe the usual and rapid gait speeds across older adults in Africa, Asia, and Australia.

Patient priority setting in HIV ageing research: exploring the feasibility of community engagement and involvement in Tanzania.

OBJECTIVE: The chronic complications of ageing with HIV are not well studied in sub-Saharan Africa (SSA) where general healthcare resources are limited. We aimed to collaborate with individuals living with HIV aged ≥ 50 years, and community elders (aged ≥ 60 years) living with non-communicable diseases in the Kilimanjaro region of Tanzania in a health research priority-setting exercise. METHODS: We conducted structured workshops based on broad questions to aid discussion and group-based patient priority setting, alongside discussion of the feasibility of future community research engagement. Participant priorities were tallied and ranked to arrive at core priorities from consensus discussion. RESULTS: Thirty older people living with HIV and 30 community elders attended separate priority setting workshops. Both groups reported motivation to participate in, conduct, and oversee future studies. In this resource-limited setting, basic needs such as healthcare access were prioritised much higher than specific HIV-complications or chronic disease. Stigma and social isolation were highly prioritised in those living with HIV. CONCLUSIONS: Community engagement and involvement in HIV and ageing research appears feasible in Tanzania. Ageing and non-communicable disease research should consider the wider context, and lack of basic needs in low-income settings. A greater impact may be achieved with community involvement.

The population in sub-Saharan Africa is ageing. The majority of people living with HIV infection also live in Africa, and they are ageing now that treatment is widely available. Current research on the chronic complications of ageing with and without HIV in sub-Saharan Africa is very limited, meaning that little is known on how to improve symptoms. In this pilot study, researchers from Tanzania and the UK worked with older people living with HIV, and community elders in Tanzania in a health research priority-setting exercise. Thirty older people living with HIV and thirty community elders attended workshops where they listed issues important to them, and then voted for each item as a group. Priorities were ranked in order of importance by adding up the number of votes. We also asked how interested and motivated older people were to work jointly with academic researchers and what might help and support them to do this. Both groups reported that they felt very motivated to participate in, conduct and oversee future research studies. A key finding was that basic needs, such as being able to see a doctor regularly and buying medications, were prioritised much higher than specific HIV-complications or chronic disease. Stigma and social isolation were important issues for older people with HIV. Our pilot findings suggest that meeting basic needs should be a key part of future work on living and ageing with chronic disease in Tanzania. The importance of working with patients and communities is also highlighted.

Prevalence and 1-year incidence of HIV-associated neurocognitive disorder (HAND) in adults aged ≥50 years attending standard HIV clinical care in Kilimanjaro, Tanzania.

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.

Health and socioeconomic resource provision for older people in South Asian countries: Bangladesh, India, Nepal, Pakistan and Sri Lanka evidence from NEESAMA.

BACKGROUND: The global population is ageing rapidly, with low- and middle-income countries (LMICs) undergoing a fast demographic transition. As the number of older adults in LMICs increases, services able to effectively address their physical and mental health needs will be increasingly important. OBJECTIVE: We review the health and socioeconomic resources currently available for older people in South Asian countries, Bangladesh, India, Nepal, Pakistan and Sri Lanka, to identify gaps in available resources and assess areas for improvement. METHODS: We conducted a search of grey and published literature via Google Search, Compendex, EBSCO, JSTOR, Medline, Ovid, ProQuest databases, Scopus and Web of Science. Data on population demographics, human resources, health funding and social protection for older people were extracted. Local informants were consulted to supplement and verify the data. RESULTS: In the study countries, the number of health professionals with expertise in elderly care was largely unknown, with minimal postgraduate training programmes available in elderly medicine or psychiatry. Older adults are therefore cared for by general physicians, nurses and community health workers, all of whom are present in insufficient numbers per capita. Total average healthcare expenditure was 2.5-5.5% of GDP, with 48.1-72.0% of healthcare costs covered by out-of-pocket payments. Pakistan did not have a social pension; only India and Nepal offered financial assistance to people with dementia; and all countries had disproportionately low numbers of care elderly homes. CONCLUSIONS: Inadequate healthcare funding, a shortage of healthcare professionals and insufficient government pension and social security schemes are significant barriers to achieving universal health coverage in LMICs. Governing bodies must expand training programmes for healthcare providers for older adults, alongside increasing social protection to improve access to those in need and to prevent catastrophic health expenditure.

Screening for delirium and dementia in older hospitalised adults in Zambia.

Delirium prevalence and aetiology in older people in hospital or community settings in sub-Saharan Africa (SSA) is largely unknown. Cognitive screening tools designed for high-income countries (HICs) may be inappropriate due to cultural and educational differences, and delirium-specific measures lack validation in this context. The 'Identification and Intervention for Dementia in Elderly Africans' (IDEA) screen is a low-literacy tool developed and validated for dementia and delirium screening in Tanzania and Nigeria. This study aims to determine the prevalence and aetiology of delirium and dementia in older hospitalised patients in Zambia and to assess the utility of the IDEA screen for identification of major cognitive impairment in this setting. This was a blinded 4-month validation study which took place February-June 2015. Consecutive inpatient admissions of a rural mission hospital aged ≥60 years were administered the IDEA screen onadmission. Individuals were evaluated for dementia or delirium based on clinical examination, notes review and the Confusion Assessment Method. Delirium aetiological factors were recorded and classified (infectious/non-infectious). Of 136 patients recruited, dementia, delirium and major cognitive impairment were identified in 37 (27.2%), 45 (33.1%) and 62 (45.6%) respectively. Diagnostic accuracy of the IDEA screen for dementia and delirium was 0.661-0.795 (AUROC). Of those with delirium, 18 (40%) were classified infectious and 26 (57.8%) were classified non-infectious aetiologies. Dementia and delirium prevalence in older Zambian inpatients is comparable tohigh-income countries. The IDEA screen ispotentially clinically useful in this setting though diagnostic accuracy was lower than in initial validation studies. Non-infectious diseases are more highly represented amongst delirium precipitants than anticipated.

Risk of conversion from mild cognitive impairment to dementia in low- and middle-income countries: A systematic review and meta-analysis.

Introduction: With no treatment for dementia, there is a need to identify high risk cases to focus preventive strategies, particularly in low- and middle-income countries (LMICs) where the burden of dementia is greatest. We evaluated the risk of conversion from mild cognitive ompairment (MCI) to dementia in LMICs. Methods: Medline, Embase, PsycINFO, and Scopus were searched from inception until June 30, 2020. The search was restricted to observational studies, conducted in population-based samples, with at least 1 year follow-up. There was no restriction on the definition of MCI used as long as it was clearly defined. PROSPERO registration: CRD42019130958. Results: Ten thousand six hundred forty-seven articles were screened; n = 11 retained. Of the 11 studies, most were conducted in China (n = 7 studies), with only two studies from countries classified as low income. A qualitative analysis of n = 11 studies showed that similar to high-income countries the conversion rate to dementia from MCI was variable (range 6 . 0%-44 . 8%; average follow-up 3 . 7 years [standard deviation = 1 . 2]). A meta-analysis of studies using Petersen criteria (n = 6 studies), found a pooled conversion rate to Alzheimer's disease (AD) of 23 . 8% (95% confidence interval = 15 . 4%-33.4%); approximately one in four people with MCI were at risk of AD in LMICs (over 3 . 0-5 . 8 years follow-up). Risk factors for conversion from MCI to dementia included demographic (e.g., age) and health (e.g., cardio-metabolic disease) variables. Conclusions: MCI is associated with high, but variable, conversion to dementia in LMICs and may be influenced by demographic and health factors. There is a notable absence of data from low-income settings and countries outside of China. This highlights the urgent need for research investment into aging and dementia in LMIC settings. Being able to identify those individuals with cognitive impairment who are at highest risk of dementia in LMICs is necessary for the development of risk reduction strategies that are contextualized to these unique settings.

Development and acceptability of a brief, evidence-based Dementia Awareness for Caregivers course in low- and middle-income countries.

BACKGROUND: Knowledge of and attitudes towards dementia vary across countries, and for caregivers in low- and middle-income countries (LMICs), access to information can be challenging. There is an urgent need for brief, easily accessible and culturally appropriate educational courses for caregivers of persons with dementia, providing much needed information whilst addressing important psychological concepts such as stigma. METHODS: An international and multidisciplinary team developed Dementia Awareness for Caregivers (DAC) courses in four stages: (1) scoping review and module agreement, (2) development of an International template (DAC-International) containing a standardised process for adding information, (3) development of local DACs using a standardised format and (4) acceptability of courses in Brazil, India and Tanzania. FINDINGS: The DAC-International was developed, comprising three modules: 'What is dementia?'; 'Positive engagement' and 'Caring for someone with dementia'. Three local versions were developed from this (DAC-Brazil, DAC-India and DAC-Tanzania), where additions of country-specific information included prevalent stereotypes and the addition of culturally relevant case studies. An initial field test was conducted in each country (n = 85), which indicated acceptability to participants. CONCLUSIONS: The methods used here resulted in culturally valid and acceptable educational courses for carers of people with dementia. Future work will consist of large-scale, formal evaluations and the development of additional local courses.

Dementia in Africa: Current evidence, knowledge gaps, and future directions.

In tandem with the ever-increasing aging population in low and middle-income countries, the burden of dementia is rising on the African continent. Dementia prevalence varies from 2.3% to 20.0% and incidence rates are 13.3 per 1000 person-years with increasing mortality in parts of rapidly transforming Africa. Differences in nutrition, cardiovascular factors, comorbidities, infections, mortality, and detection likely contribute to lower incidence. Alzheimer's disease, vascular dementia, and human immunodeficiency virus/acquired immunodeficiency syndrome-associated neurocognitive disorders are the most common dementia subtypes. Comprehensive longitudinal studies with robust methodology and regional coverage would provide more reliable information. The apolipoprotein E (APOE) ε4 allele is most studied but has shown differential effects within African ancestry compared to Caucasian. More candidate gene and genome-wide association studies are needed to relate to dementia phenotypes. Validated culture-sensitive cognitive tools not influenced by education and language differences are critically needed for implementation across multidisciplinary groupings such as the proposed African Dementia Consortium.

Development of a brief screening method for identification of depression in older adults in Sub-Saharan Africa.

OBJECTIVES: To develop a brief, culturally appropriate screening tool for identifying late life depression (LLD), for use by non-specialist clinicians in primary and out-patient care settings in sub-Saharan Africa (SSA). BACKGROUND: Depressive disorders are a leading contributor to the global health burden. LLD is common and cases will increase as populations' age, particularly in low- and middle-income countries (LMICs), such as those in SSA. A chronic mental health workforce shortage and the absence of culturally adapted LLD screening tools to aid non-specialist clinicians have contributed to a significant diagnostic gap. DESIGN: A systematic random sample of older people attending general medical clinics were interviewed using a 30-item LLD questionnaire, developed utilizing a Delphi consensus analysis of items from the Geriatric Depression Scale, Patient Health Questionnaire-2 and questions developed from a study of lay conceptualisations of depression in Tanzania. The items were assessed for validity against blinded DSM 5 diagnosis of depression by a research doctor. Factor and item analysis were then used to refine the questionnaire. RESULTS: The 12-item Maddison Old-age Scale for Identifying Depression (MOSHI-D) was developed. It has good internal consistency (Cronbach's α = 0.820) and construct and criterion validity (AUROC = 0.880). CONCLUSIONS: On initial evaluation, the MOSHI-D showed good internal validity. It should be easy for non-specialists to administer. External validation and further refinement will be conducted. A culturally-appropriate LLD screen may improve mental health care integration into existing healthcare settings within SSA and facilitate greater patient access to care, in accordance with current WHO strategy.

Screening tools for common mental disorders in older adults in South Asia: a systematic scoping review.

OBJECTIVES: Common mental disorders (CMDs), particularly depression, are major contributors to the global mental health burden. South Asia, while diverse, has cultural, social, and economic challenges, which are common across the region, not least an aging population. This creates an imperative to better understand how CMD affects older people in this context, which relies on valid and culturally appropriate screening and research tools. This review aims to scope the availability of CMD screening tools for older people in South Asia. As a secondary aim, this review will summarize the use of these tools in epidemiology, and the extent to which they have been validated or adapted for this population. DESIGN: A scoping review was performed, following PRISMA guidelines. The search strategy was developed iteratively in Medline and translated to Embase, PsychInfo, Scopus, and Web of Science. Data were extracted from papers in which a tool was used to identify CMD in a South Asian older population (50+), including validation, adaptation, and use in epidemiology. Validation studies meeting the criteria were critically appraised using the Quality Assessment of Diagnostic Accuracy Studies - version 2 (QUADAS-2) tool. RESULTS: Of the 4694 papers identified, 176 met the selection criteria at full-text screening as relevant examples of diagnostic or screening tool use. There were 15 tool validation studies, which were critically appraised. Of these, 10 were appropriate to evaluate as diagnostic tests. All of these tools assessed for depression. Geriatric Depression Scale (GDS)-based tools were predominant with variable diagnostic accuracy across different settings. Methodological issues were substantial based on the QUADAS-2 criteria. In the epidemiological studies identified (n = 160), depression alone was assessed for 82% of the studies. Tools lacking cultural validation were commonly used (43%). CONCLUSIONS: This review identifies a number of current research gaps including a need for culturally relevant validation studies, and attention to other CMDs such as anxiety.

Population normative data for three cognitive screening tools for older adults in sub-Saharan Africa.

In sub-Saharan Africa (SSA),cognitive screening is complicated by both cultural and educational factors, and the existing normative values may not be applicable. The Identification of Dementia in Elderly Africans (IDEA) cognitive screen is a low-literacy measure with good diagnostic accuracy for dementia. OBJECTIVE: The aim of this study is to report normative values for IDEA and other simple measures [i.e., categorical verbal fluency, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) 10-word list] in representative community-dwelling older adults in SSA. METHODS: Individuals aged ≥60 years resident in 12 representative villages in Kilimanjaro, Tanzania and individuals aged ≥65 years resident within three communities in Akinyele Local Government Area, Oyo State, Nigeria underwent cognitive screening. The normative data were generated by the categories of age, sex, and education. RESULTS: A total of 3,011 people in Tanzania (i.e., 57.3% females and 26.4% uneducated) and 1,117 in Nigeria (i.e., 60.3% females and 64.5% uneducated) were screened. Individuals with higher age, lower education, and female gender obtained lower scores. The 50th decile values for IDEA were 13 (60-64 years) vs. 8/9 (above 85 years), 10-11 uneducated vs. 13 primary educated, and 11/12 in females vs. 13 in males. The normative values for 10-word list delayed recall and categorical verbal fluency varied with education [i.e., delayed recall mean 2.8 [standard deviation (SD) 1.7] uneducated vs. 4.2 (SD 1.2) secondary educated; verbal fluency mean 9.2 (SD 4.8) uneducated vs. 12.2 (SD 4.3) secondary educated], substantially lower than published high-income country values. CONCLUSIONS: The cut-off values for commonly used cognitive screening items should be adjusted to suit local normative values, particularly where there are lower levels of education.

Na África Subsaariana (ASS), a triagem cognitiva é complicada por fatores culturais e educacionais, além dos valores normativos existentes poderem não ser aplicáveis. O rastreio cognitivo Identification of Dementia in Elderly Africans (IDEA) é uma medida para níveis baixos de alfabetização com boa acurácia diagnóstica para demência. OBJETIVO: Relatar os valores normativos para a IDEA e outras medidas simples (fluência verbal categórica, a lista de 10 palavras do Consortium to Establish a Registry for Alzheimer's Disease (CERAD) em idosos residentes na comunidade, representativos da ASS. Métodos: Indivíduos com idade ≥60 residentes em 12 comunidades representativas em Kilimanjaro, Tanzânia e indivíduos com idade ≥65 anos residentes em três comunidades na área governamental de Akinyele, Estado de Oyo, Nigéria, foram submetidos à triagem cognitiva. Os dados normativos foram gerados por faixas etárias, sexo e escolaridade. RESULTADOS: Um total de 3.011 pessoas na Tanzânia (57,3% mulheres, 26,4% sem educação) e 1.117 na Nigéria (60,3% mulheres, 64,5% sem educação) foram examinadas. Os indivíduos com idade mais alta, menor escolaridade e mulheres obtiveram escores mais baixos. Os valores do percentil 50 para a IDEA foram 13 (60­64 anos) vs. 8/9 (85+ anos), 10­11 para analfabetos vs. 13 com educação primária e 11/12 em mulheres vs. 13 em homens. Os valores normativos para a evocação tardia da lista de 10 palavras e a fluência verbal categórica variaram com a educação (evocação tardia 2,8 (SD 1,7) para os sem educação, vs. 4,2 (SD 1,2) para com educação secundária; fluência verbal 9,2 (DP 4,8) para os sem educação vs. 12,2 (SD 4.3) para os com ensino médio, substancialmente inferior aos valores publicados em países de alta renda. CONCLUSÕES: Os valores de corte para testes de triagem cognitiva comumente usados devem ser ajustados para se adequar aos valores normativos locais, particularmente em níveis baixos de educação.

Population normative data for three cognitive screening tools for older adults in sub-Saharan Africa / Dados normativos populacionais para três instrumentos de triagem cognitiva para idosos na áfrica subsaariana

ABSTRACT In sub-Saharan Africa (SSA),cognitive screening is complicated by both cultural and educational factors, and the existing normative values may not be applicable. The Identification of Dementia in Elderly Africans (IDEA) cognitive screen is a low-literacy measure with good diagnostic accuracy for dementia. Objective: The aim of this study is to report normative values for IDEA and other simple measures [i.e., categorical verbal fluency, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) 10-word list] in representative community-dwelling older adults in SSA. Methods: Individuals aged ≥60 years resident in 12 representative villages in Kilimanjaro, Tanzania and individuals aged ≥65 years resident within three communities in Akinyele Local Government Area, Oyo State, Nigeria underwent cognitive screening. The normative data were generated by the categories of age, sex, and education. Results: A total of 3,011 people in Tanzania (i.e., 57.3% females and 26.4% uneducated) and 1,117 in Nigeria (i.e., 60.3% females and 64.5% uneducated) were screened. Individuals with higher age, lower education, and female gender obtained lower scores. The 50th decile values for IDEA were 13 (60-64 years) vs. 8/9 (above 85 years), 10-11 uneducated vs. 13 primary educated, and 11/12 in females vs. 13 in males. The normative values for 10-word list delayed recall and categorical verbal fluency varied with education [i.e., delayed recall mean 2.8 [standard deviation (SD) 1.7] uneducated vs. 4.2 (SD 1.2) secondary educated; verbal fluency mean 9.2 (SD 4.8) uneducated vs. 12.2 (SD 4.3) secondary educated], substantially lower than published high-income country values. Conclusions: The cut-off values for commonly used cognitive screening items should be adjusted to suit local normative values, particularly where there are lower levels of education.

RESUMO Na África Subsaariana (ASS), a triagem cognitiva é complicada por fatores culturais e educacionais, além dos valores normativos existentes poderem não ser aplicáveis. O rastreio cognitivo Identification of Dementia in Elderly Africans (IDEA) é uma medida para níveis baixos de alfabetização com boa acurácia diagnóstica para demência. Objetivo: Relatar os valores normativos para a IDEA e outras medidas simples (fluência verbal categórica, a lista de 10 palavras do Consortium to Establish a Registry for Alzheimer's Disease (CERAD) em idosos residentes na comunidade, representativos da ASS. Métodos: Indivíduos com idade ≥60 residentes em 12 comunidades representativas em Kilimanjaro, Tanzânia e indivíduos com idade ≥65 anos residentes em três comunidades na área governamental de Akinyele, Estado de Oyo, Nigéria, foram submetidos à triagem cognitiva. Os dados normativos foram gerados por faixas etárias, sexo e escolaridade. Resultados: Um total de 3.011 pessoas na Tanzânia (57,3% mulheres, 26,4% sem educação) e 1.117 na Nigéria (60,3% mulheres, 64,5% sem educação) foram examinadas. Os indivíduos com idade mais alta, menor escolaridade e mulheres obtiveram escores mais baixos. Os valores do percentil 50 para a IDEA foram 13 (60-64 anos) vs. 8/9 (85+ anos), 10-11 para analfabetos vs. 13 com educação primária e 11/12 em mulheres vs. 13 em homens. Os valores normativos para a evocação tardia da lista de 10 palavras e a fluência verbal categórica variaram com a educação (evocação tardia 2,8 (SD 1,7) para os sem educação, vs. 4,2 (SD 1,2) para com educação secundária; fluência verbal 9,2 (DP 4,8) para os sem educação vs. 12,2 (SD 4.3) para os com ensino médio, substancialmente inferior aos valores publicados em países de alta renda. Conclusões: Os valores de corte para testes de triagem cognitiva comumente usados devem ser ajustados para se adequar aos valores normativos locais, particularmente em níveis baixos de educação.

Instrumental Activities of Daily Living Scales to Detect Cognitive Impairment and Dementia in Low- and Middle-Income Countries: A Systematic Review.

BACKGROUND: The largest proportion of people with dementia worldwide live in low- and middle- income countries (LMICs), with dementia prevalence continuing to rise. Assessment and diagnosis of dementia involves identifying the impact of cognitive decline on function, usually measured by instrumental activities of daily living (IADLs). OBJECTIVE: This review aimed to identify IADL measures which are specifically developed, validated, or adapted for use in LMICs to guide selection of such tools. METHODS: A systematic search was conducted (fourteen databases) up to April 2020. Only studies reporting on development, validation, or adaptation of IADL measures for dementia or cognitive impairment among older adults (aged over 50) in LMICs were included. The QUADAS 2 was used to assess quality of diagnostic accuracy studies. RESULTS: 22 papers met inclusion criteria; identifying 19 discrete IADL tools across 11 LMICs. These were either translated from IADL measures used in high-income countries (n = 6), translated and adapted for cultural differences (n = 6), or newly developed for target LMIC populations (n = 7). Seven measures were investigated in multiple studies; overall quality of diagnostic accuracy was moderate to good. CONCLUSION: Reliability, validity, and accuracy of IADL measures for supporting dementia diagnosis within LMICs was reported. Key components to consider when selecting an IADL tool for such settings were highlighted, including choosing culturally appropriate, time-efficient tools that account for gender- and literacy-bias, and can be conducted by any volunteer with appropriate training. There is a need for greater technical and external validation of IADL tools across different regions, countries, populations, and cultures.