Cognitive screening instruments for dementia: comparing metrics of test limitation / Instrumentos de rastreio cognitivo para a demência: comparação métrica da limitação dos testes

ABSTRACT Cognitive screening instruments (CSIs) for dementia and mild cognitive impairment are usually characterized in terms of measures of discrimination such as sensitivity, specificity, and likelihood ratios, but these CSIs also have limitations. Objective: The aim of this study was to calculate various measures of test limitation for commonly used CSIs, namely, misclassification rate (MR), net harm/net benefit ratio (H/B), and the likelihood to be diagnosed or misdiagnosed (LDM). Methods: Data from several previously reported pragmatic test accuracy studies of CSIs (Mini-Mental State Examination, the Montreal Cognitive Assessment, Mini-Addenbrooke's Cognitive Examination, Six-item Cognitive Impairment Test, informant Ascertain Dementia 8, Test Your Memory test, and Free-Cog) undertaken in a single clinic were reanalyzed to calculate and compare MR, H/B, and the LDM for each test. Results: Some CSIs with very high sensitivity but low specificity for dementia fared poorly on measures of limitation, with high MRs, low H/B, and low LDM; some had likelihoods favoring misdiagnosis over diagnosis. Tests with a better balance of sensitivity and specificity fared better on measures of limitation. Conclusions: When deciding which CSI to administer, measures of test limitation as well as measures of test discrimination should be considered. Identification of CSIs with high MR, low H/B, and low LDM, may have implications for their use in clinical practice.

RESUMO Os instrumentos de rastreio cognitivo (IRCs) para demência e comprometimento cognitivo leve são geralmente caracterizados em termos de medidas de discriminação, como sensibilidade, especificidade e razões de probabilidade, mas esses IRCs também têm limitações. Objetivo: Calcular várias medidas de limitação de testes para IRC comumente usados, a saber: taxa de classificação incorreta; relação entre dano líquido e benefício líquido; e probabilidade de diagnóstico ou diagnóstico incorreto. Métodos: Os dados de vários estudos de precisão de teste pragmático de IRC relatados anteriormente (MMSE, MoCA, MACE, 6CIT, AD8, TYM, Free-Cog) e realizados em uma única clínica foram reanalisados para calcular e comparar a taxa de classificação incorreta, o dano líquido para a relação de benefício líquido e a probabilidade de diagnóstico ou diagnóstico incorreto para cada teste. Resultados: Alguns IRC com sensibilidade muito alta, mas baixa especificidade para demência, tiveram desempenho ruim em medidas de limitação, com altas taxas de classificação incorreta, baixo prejuízo líquido para relações de benefício líquido e baixa probabilidade de diagnóstico ou diagnóstico incorreto; alguns tinham probabilidades de favorecer o diagnóstico incorreto ao invés do diagnóstico. Testes com melhor equilíbrio de sensibilidade e especificidade saíram-se melhor nas medidas de limitação. Conclusões: Ao decidir qual IRC administrar, as medidas de limitação, bem como as medidas de discriminação do teste, devem ser consideradas. A identificação de IRC com alta taxa de classificação incorreta, baixa relação de prejuízo e benefício e baixa probabilidade de diagnóstico ou diagnóstico incorreto pode ter implicações para seu uso na prática clínica.

Evaluating a Memory Clinic Using the RE-AIM Model. The Experience of the "Memory and Neuropsychiatry Clinic" in Hospital Del Salvador, Chile.

The development of healthcare services for dementia is key to improving access to care and post-diagnostic support for people living with dementia. Memory Units have emerged as a new healthcare service composed of multidisciplinary teams with the goal of improving diagnosis and/or management of dementia patients. The main objective of this study was to describe and evaluate the Reach and Effectiveness of a Memory Unit in a public hospital in Chile, using the RE-AIM model, a multi-component model that allows for the evaluation of the implementation of ongoing healthcare programs. Regarding "R" (Reach): from March 2018 up to June 2019, a total of 510 patients were referred and assessed. Most patients came from primary care (51.9%) and from outpatient services at the Hospital Salvador (39.2%), particularly from the Neurology (63.3%) and Psychiatry (16.0%) departments. We estimated that our Memory Unit assessed 5.39% of all of the dementia patients living in the area of referral. With respect to "E" (Effectiveness): 419 patients are still being followed up at the Memory Unit. Ninety-one patients (18%) were discharged. Of these, 55 (66%) were referred to primary healthcare, 28 (31%) to other outpatient services, 9 (10%) to a specialized mental healthcare center, and 9 (10%) to a daycare center. Due to the short period of time that the Memory Unit has been operating, no other RE-AIM dimensions could be evaluated at this juncture. To our knowledge, this is the first implementation study of a Memory Unit in Latin America, and the first using the RE-AIM model. Although cultural differences worldwide might play a role in the lack of international guidelines, the publication of the experience of the first year of this unit in Chile could inform new countries about this process. Ongoing challenges include continuing to collect data to complement the RE-AIM evaluation and developing a protocol that can be adopted elsewhere in Chile and Latin America. Further studies are needed to assess the benefits of a Memory Unit in comparison to regular care and to develop a model that assures continuity and coordination of care for people with dementia.

Cognitive screening instruments for dementia: comparing metrics of test limitation.

Cognitive screening instruments (CSIs) for dementia and mild cognitive impairment are usually characterized in terms of measures of discrimination such as sensitivity, specificity, and likelihood ratios, but these CSIs also have limitations. Objective: The aim of this study was to calculate various measures of test limitation for commonly used CSIs, namely, misclassification rate (MR), net harm/net benefit ratio (H/B), and the likelihood to be diagnosed or misdiagnosed (LDM). Methods: Data from several previously reported pragmatic test accuracy studies of CSIs (Mini-Mental State Examination, the Montreal Cognitive Assessment, Mini-Addenbrooke's Cognitive Examination, Six-item Cognitive Impairment Test, informant Ascertain Dementia 8, Test Your Memory test, and Free-Cog) undertaken in a single clinic were reanalyzed to calculate and compare MR, H/B, and the LDM for each test. Results: Some CSIs with very high sensitivity but low specificity for dementia fared poorly on measures of limitation, with high MRs, low H/B, and low LDM; some had likelihoods favoring misdiagnosis over diagnosis. Tests with a better balance of sensitivity and specificity fared better on measures of limitation. Conclusions: When deciding which CSI to administer, measures of test limitation as well as measures of test discrimination should be considered. Identification of CSIs with high MR, low H/B, and low LDM, may have implications for their use in clinical practice.

Os instrumentos de rastreio cognitivo (IRCs) para demência e comprometimento cognitivo leve são geralmente caracterizados em termos de medidas de discriminação, como sensibilidade, especificidade e razões de probabilidade, mas esses IRCs também têm limitações. Objetivo: Calcular várias medidas de limitação de testes para IRC comumente usados, a saber: taxa de classificação incorreta; relação entre dano líquido e benefício líquido; e probabilidade de diagnóstico ou diagnóstico incorreto. Métodos: Os dados de vários estudos de precisão de teste pragmático de IRC relatados anteriormente (MMSE, MoCA, MACE, 6CIT, AD8, TYM, Free-Cog) e realizados em uma única clínica foram reanalisados para calcular e comparar a taxa de classificação incorreta, o dano líquido para a relação de benefício líquido e a probabilidade de diagnóstico ou diagnóstico incorreto para cada teste. Resultados: Alguns IRC com sensibilidade muito alta, mas baixa especificidade para demência, tiveram desempenho ruim em medidas de limitação, com altas taxas de classificação incorreta, baixo prejuízo líquido para relações de benefício líquido e baixa probabilidade de diagnóstico ou diagnóstico incorreto; alguns tinham probabilidades de favorecer o diagnóstico incorreto ao invés do diagnóstico. Testes com melhor equilíbrio de sensibilidade e especificidade saíram-se melhor nas medidas de limitação. Conclusões: Ao decidir qual IRC administrar, as medidas de limitação, bem como as medidas de discriminação do teste, devem ser consideradas. A identificação de IRC com alta taxa de classificação incorreta, baixa relação de prejuízo e benefício e baixa probabilidade de diagnóstico ou diagnóstico incorreto pode ter implicações para seu uso na prática clínica.

Características clínicas de los casos de demencia diagnosticados en la Clínica de Memoria del Hospital Nacional de Geriatría y Gerontología / Clinical aspects of dementia cases diagnosed at the Memory Clinic of the National Geriatric and Gerontology Hospital

Antecedentes: la demencia es una entidad clínica cada vez más prevalente en nuestro medio, cuya incidencia aumenta con la edad. El objetivo del presente estudio es identificar los principales tipos de demencia atendidos en una unidad de trastornos de memoria. Métodos: registro consecutivo y estandarizado de pacientes diagnosticados con demencia en la Unidad de Trastornos de Memoria y Conducta, del Hospital Nacional de Geriatría y Gerontología. Resultados: se evaluó 1659 casos, de los cuales el 65,8% reunió criterios de demencia. El 42,9% correspondió a enfermedad de Alzheimer, el 28,5% a demencia secundaria a patología vascular, el 17,1% a formas mixtas, y el 11,5% a tipos varios. La edad media fue de 79,6 + 6,7 años, y el 66,2% fueron mujeres. La escolaridad promedio fue 4,95 + 4,09 años; el 41,7% estaba casado; el 47,3% tenía un hijo como cuidador; el tiempo promedio entre la aparición de los síntomas y el diagnóstico clínico fue de 3,18 + 2,6 años. La puntuación media del test Minimental fue de 18,35 + 5,9 puntos; en el test de dibujo del reloj fue de 3,4 + 2,5, y el Clinical Dementia Rating fue de 1,7 + 0,7; el 45,2% de los casos correspondió a CDR de 1. El 24% de los casos tenía antecedente familiar de demencia, y el 95,7% presentaba uno o más factores de riesgo cardiovascular, siendo la HTA el más frecuente, en un 70,2%. El 27,1% de los casos fue demencias leves; el 31,9%, moderadas; el 39,3% moderadas-severas, y el 1,7%, severas. El 90% de los casos presentó uno o más trastornos neuroconductuales. Conclusiones: la determinación de los principales tipos de demencia en la población adulta mayor y sus principales características, ha permitido registrar gran cantidad de información que se desconocía y que será de útil para la gestión y planificación de estrategias de atención en salud pública.

Background: Dementia is an increasingly prevalent clinical entity in the medical field, whose incidence increases with age. The purpose of this study is to identify the main types of dementia treated in a memory-disorders unit. Methodology: A consecutive and standardized register of patients diagnosed with dementia at the Memory Disorders Unit of the National Geriatrics and Gerontology Hospital. Results: 1659 cases were evaluated, 65.8% met criteria for dementia. 42.9% of the cases were Alzheimer’s disease, 28.5% secondary vascular dementia pathology, mixed forms represented 17.1% and 11.5% were diverse types. The mean age was 79.6 + 6.7 years and 66.2% were women. Average schooling was 4.95+ 4.09 years, 41.7% were married, 47.3% had a child as a caregiver, the average time between onset of symptoms and the clinical diagnosis was 3.18 + 2.6 years. The mean Minimental test score was 18.35 + 5.9 points, in the clock drawing test it was 3.4 + 2.5 and the Clinical Dementia Rating was 1.7 + 0.7; 45.2% of cases were CDR 1. 24% of cases had a family history of dementia and 95.7% had one or more cardiovascular risk factors, with AHT being the most common in 70.2%. 27.1% of dementia cases were mild, 31.9% moderate, 39.3% moderatesevere and 1.7% were severe. 90% of patients had one or more neurobehavioral disorders. Conclusions: The determination of the main types of dementia in the elderly population and their main features has allowed the registry of abundant information that was unknown and that will be useful for the management and strategic planning of public health care.

Concordance between 11C-PIB-PET and clinical diagnosis in a memory clinic.

INTRODUCTION: Today, ligands that bind to fibrillar ß-amyloid are detectable by Positron Emission Tomography (PET) allowing for in vivo visualization for Abeta burden. However, amyloid plaques detection per se does not establish Alzheimer's Disease diagnosis. In this sense, the utility of amyloid imaging to improve clinical diagnosis was settled only for specific clinical scenarios and few studies have assessed amyloid molecular neuroimaging in a broader clinical setting. The aim of this study is to determine the frequency of PiB amyloid findings in different diagnostic syndromes grouped into high and low probability pre- test categories, taking into account pre-test clinical assumption of the presence of AD related pathology. METHODS: 144 patients were assigned into categories of high or low pretest probability according to clinical suspicion of AD pathology. The high probability group included: amnestic Mild Cognitive Impairment (MCI), amnestic and other domains MCI, Dementia of Alzheimer's Type (DAT), Posterior Cortical Atrophy (PCA), logopenic Primary Progressive Aphasia (PPA), Cerebral Amyloid Angiopathy and mixed dementia. The low assumption group included: normal controls, non-amnestic MCI, non-logopenic PPA and Frontotemporal Dementia (FTD). RESULTS: Only normal controls and DAT patients (typical and atypical presentation) were the most consistent across clinical and molecular diagnostics. MCI, non-logopenic PPA and FTD were the syndromic diagnoses that most discrepancies were found. DISCUSSION: This study demonstrates that detecting in vivo amyloid plaques by molecular imaging is considerably frequent in most of the dementia syndromes and shows that there are frequent discordance between molecular diagnosis and clinical assumption.

Memory clinic experience under a social security health system in Costa Rica / Experiência de uma clínica de memória do sistema social de saúde da Costa Rica

Dementia and mild cognitive impairment (MCI) are an increasingly prevalent clinical entity in our , showing an increasing incidence with age. Objective: The purpose of this study was to identify the main types of dementia and MCI treated in a memory disorders unit in Costa Rica. Methods: A consecutive and standardized register of patients diagnosedwith dementia and MCI at the memory disorders unit of the National Geriatrics and Gerontology Hospital (NGGH) was analyzed. Results: Dementia was diagnosed in 63.5% of the 3572 cases, whereas 10.6% met criteria for MCI. The most frequent type of dementia was Alzheimers disease (47.1%), followed by vascular pathology (28.9%), mixed forms (17.2%) and other types (6.8%). In MCI, 69.5% were of amnestic multiple domain type and 14.3% were non-amnestic multiple domain, while 41.3% were of vascular and 35.8% of neurodegenerative etiology. Mean age was 79.6±6.7 years and 64.7% were women in dementia cases whereas mean age was 76.4±6.9 years and 62.1% were women in MCI. Mean years of schooling was 4.95±4.09 years and 6.87±4.71, while mean time between onset of symptoms and clinical diagnosis was 3.2±2.6 years and 2.67±2.69 years, in dementia and MCI, respectively. Conclusion: The determination of the main types of dementia and MCI in Costa Rica and their main features has allowed the registration of comprehensive, hitherto unavailable information that will be useful for the management and strategic planning of public health care.

Demência e transtorno cognitivo leve (CCL) é uma entidade clínica cada vez mais prevalente, mostrando uma incidência crescente com a idade. Objetivo: O objetivo deste estudo foi o de identificar os principais tipos de demência e CCL tratados em uma unidade de transtornos da memória de Costa Rica. Métodos: Um registo consecutivo e padronizado de pacientes com diagnóstico de demência e CCL na unidade de transtorno de memória do Hospital Geral de Geriatria e Gerontologia. Resultados: Demência foi diagnosticada em 63,5% dos 3.572 casos, enquanto 10,6% tiveram diagnóstico de CCL. O tipo mais frequente de demência foi a doença de Alzheimer (47,1%), seguido de doença vascular (28,9%), formas mistas (17,2%) e outros tipos (6,8%). No CCL, 69,5% eram de tipo amnéstico de múltiplos domínios e 14,3% eram não amnésticos de múltiplos domínios, enquanto 41,3% eram de etiologia vascular e 35,8% de etiologia neurodegenerativa. A média de idade foi de 79,6±6,7 anos e 64,7% eram mulheres em casos de demência ao passo que a média de idade foi de 76,4±6,9 anos e 62,1% eram mulheres nos casos de CCL. A média de anos de estudo foi de 4,95±4,09 anos e 6,87±4,71, o tempo entre o início dos sintomas e o diagnóstico clínico médio foi de 3,2±2,6 anos e 2,67±2,69 anos em demência e CCL, respectivamente. Conclusão: A determinação dos principais tipos de demência e CCL na Costa Rica e as suas principais características permitiu o registro de informação abundante que era desconhecida e que será útil para a gestão e planejamento estratégico da saúde pública.

Memory clinic experience under a social security health system in Costa Rica.

Dementia and mild cognitive impairment (MCI) are an increasingly prevalent clinical entity in our field, showing an increasing incidence with age. OBJECTIVE: The purpose of this study was to identify the main types of dementia and MCI treated in a memory disorders unit in Costa Rica. METHODS: A consecutive and standardized register of patients diagnosed with dementia and MCI at the memory disorders unit of the National Geriatrics and Gerontology Hospital (NGGH) was analyzed. RESULTS: Dementia was diagnosed in 63.5% of the 3572 cases, whereas 10.6% met criteria for MCI. The most frequent type of dementia was Alzheimer's disease (47.1%), followed by vascular pathology (28.9%), mixed forms (17.2%) and other types (6.8%). In MCI, 69.5% were of amnestic multiple domain type and 14.3% were non-amnestic multiple domain, while 41.3% were of vascular and 35.8% of neurodegenerative etiology. Mean age was 79.6±6.7 years and 64.7% were women in dementia cases whereas mean age was 76.4±6.9 years and 62.1% were women in MCI. Mean years of schooling was 4.95±4.09 years and 6.87±4.71, while mean time between onset of symptoms and clinical diagnosis was 3.2±2.6 years and 2.67±2.69 years, in dementia and MCI, respectively. CONCLUSION: The determination of the main types of dementia and MCI in Costa Rica and their main features has allowed the registration of comprehensive, hitherto unavailable information that will be useful for the management and strategic planning of public health care.

Demência e transtorno cognitivo leve (CCL) é uma entidade clínica cada vez mais prevalente, mostrando uma incidência crescente com a idade. OBJETIVO: O objetivo deste estudo foi o de identificar os principais tipos de demência e CCL tratados em uma unidade de transtornos da memória de Costa Rica. MÉTODOS: Um registo consecutivo e padronizado de pacientes com diagnóstico de demência e CCL na unidade de transtorno de memória do Hospital Geral de Geriatria e Gerontologia. RESULTADOS: Demência foi diagnosticada em 63,5% dos 3.572 casos, enquanto 10,6% tiveram diagnóstico de CCL. O tipo mais frequente de demência foi a doença de Alzheimer (47,1%), seguido de doença vascular (28,9%), formas mistas (17,2%) e outros tipos (6,8%). No CCL, 69,5% eram de tipo amnéstico de múltiplos domínios e 14,3% eram não-amnéstcios de múltiplos domínios, enquanto 41,3% eram de etiologia vascular e 35,8% de etiologia neurodegenerativa. A média de idade foi de 79,6±6,7 anos e 64,7% eram mulheres em casos de demência ao passo que a média de idade foi de 76,4±6,9 anos e 62,1% eram mulheres nos casos de CCL. A média de anos de estudo foi de 4,95±4,09 anos e 6,87±4,71, o tempo entre o início dos sintomas eo diagnóstico clínico médio foi de 3,2±2,6 anos e 2,67±2,69 anos em demência e CCL, respectivamente. CONCLUSÃO: A determinação dos principais tipos de demência e CCL na Costa Rica e as suas principais características permitiu o registro de informação abundante que era desconhecida e que será útil para a gestão e planejamento estratégico da saúde pública.

Assessment of memory complainers in São Paulo, Brazil: Three-year results of a memory clinic.

Memory clinics were established in the USA and European countries as services to attend patients who complain of cognitive deficits, referred by primary care doctors, specialists and other hospitals. OBJECTIVE: We aimed to describe the clinical and cognitive profile of consecutively evaluated subjects during the initial three years of service of a memory clinic from a university hospital. METHODS: Subjects were submitted to a clinical work-up for dementia, which included laboratory exams, cranial computerized tomography, cognitive tests, and a comprehensive neuropsychological battery. Diagnosis was made according to ICD-10 criteria. RESULTS: We evaluated 104 subjects (67.3% females and 32.7% males), with mean age of 59.1 years, 88.8% aged 50 years or above. Mean schooling was 9.9 years. Patients were classified into 10 different primary diagnostic categories, namely Depression (26.9%), Alzheimer's disease (17.3%), Memory complaints without objective impairment (17.3%), Mild Cognitive Disorder - MCD (14.4%), and Anxiety (12.5%) the most frequent diagnosis. Comparing patients with dementia, MCD, Depression or Anxiety and Memory complainers, by age (below and above 60 years), dementia was more commonly diagnosed in older subjects, while a higher frequency of memory complainers was found in the younger group. CONCLUSIONS: This preliminary report from an outpatient group of referred patients with cognitive complaints showed a higher frequency of psychiatric disorders in this sample. The memory clinic approach should be considered as a model of service which can evaluate subjects with cognitive complaints effectively and improve the quality of care delivered to this patient group.

Clínicas de memória foram estabelecidas nos EUA e em países europeus como serviços para atender pacientes que se queixam de déficits cognitivos, encaminhados por médicos em cuidados primários, especialistas e outros hospitais. OBJETIVO: Nós pretendemos descrever o perfil clínico e cognitivo de sujeitos consecutivamente avaliados nos primeiros três anos de funcionamento de uma clínica de memória de um hospital universitário. METÓDOS: Os sujeitos foram submetidos a avaliação clínica para demência, incluindo exames laboratoriais, tomografia computadorizada de crânio, testes cognitivos e uma bateria neuropsicológica completa. Diagnóstico foi feito segundo critérios da CID-10. RESULTADOS: Nós avaliamos 104 sujeitos (67,3% mulheres e 32,7% homens), com idade média de 59,1 anos, 88,8% com mais de 50 anos de idade. A escolaridade média era de 9,9 anos. Pacientes foram classificados em 10 categorias diagnósticas primárias diferentes, sendo Depressão (26,9%), doença de Alzheimer (17,3%), Queixas de memória sem comprometimento objetivo (17,3%), Transtorno cognitivo leve ­ TCL (14,4%), e Ansiedade (12,5%) as mais freqüentes. Comparando pacientes com demência, TCL, Depressão ou Ansiedade e aqueles com Queixa de memória, por idade (abaixo e acima de 60 anos), demência foi mais comumente diagnosticada nos idosos, enquanto maior freqüência daqueles com queixa de memória foi encontrada nos mais jovens. CONCLUSÕES: Este relato preliminar de pacientes ambulatoriais encaminhados com queixas cognitivas mostrou uma freqüência elevada de transtornos psiquiátricos nesta amostra. A abordagem da clínica de memória deveria ser considerada como um modelo de serviço para avaliar efetivamente sujeitos com queixas cognitivas, podendo melhorar a qualidade do cuidado prestado a estas pessoas.