Cross-sectional assessment of mild cognitive impairment in pre-dialysis chronic kidney disease and its association with inflammation and changes seen on MRI: what the eyes cannot see / Avaliação transversal do comprometimento cognitivo leve em doença renal crônica pré-dialítica e associação com inflamação e alterações na ressonância magnética: o que os olhos não veem

Abstract Introduction: Mild cognitive impairment (MCI) is a prevalent and underdiagnosed condition in chronic kidney disease (CKD), that shares common pathophysiological factors such as chronic inflammation. Objective: To evaluate the association of MCI in CKD stages 1-5 using inflammatory markers and changes by magnetic resonance imaging (MRI). Patients and Methods: Cross-sectional study in adult patients with pre-dialysis CKD. MCI was assessed by the Montreal Cognitive Assessment (MoCA) and the estimated glomerular filtration rate (eGFR) by the Chronic Kidney Disease Epidemiology Collaboration equation. Sociodemographic and clinical data were collected from medical records. The cytokines IL-4, IL-6, IL-17, TNF-α and hs-CRP were determined. Brain MRI was performed in a 1.5 Tesla device, without paramagnetic contrast. A descriptive analysis followed by a comparison of abnormal versus normal MoCA scores among all studied variables. A linear regression analysis was performed using MoCA as a dependent variable, adjusted for confounding factors. Results: Of 111 invited patients, eighty completed the neuropsychological assessment and 56 underwent MRI, and were included in the study. Mean age was 56.3 ± 8.3 years and 51.8% (n = 29) had altered MoCA. When compared to the group with normal MoCA, the group with altered MoCA had higher levels of IL-6 and IL-17. There was no correlation between altered MoCA with eGFR or with MRI abnormalities. Conclusão: MCI assessed by MoCA was prevalent in patients with pre-dialysis CKD, it was associated with inflammation and showed no correlation with MRI changes.

Resumo Introdução: O comprometimento cognitivo leve (CCL) é prevalente e subdiagnosticado na doença renal crônica (DRC), condição com a qual compartilha fatores fisiopatológicos como a inflamação crônica. Objetivo: Avaliar a associação do CCL na DRC estágios 1 a 5, com marcadores inflamatórios e alterações de exames de imagem por ressonância magnética (RM). Pacientes e métodos: Estudo transversal em pacientes adultos, com DRC pré-dialítica. CCL foi avaliado pelo Montreal Cognitive Assessment (MoCA) e a taxa de filtração glomerular estimada (TFGe), pela equação do CKD-EPI. Dados sociodemográficos e clínicos foram coletados nos prontuários médicos. Dosadas citocinas IL-4, IL-6, IL-17, o TNF-α e PCR-us. A RM do encéfalo foi realizada em aparelho de 1,5 Tesla, sem contraste. Realizada análise descritiva seguida por comparação de pontuações do MoCA anormais versus normais entre todas as variáveis estudadas. A regressão linear foi realizada usando MoCA como uma variável dependente, ajustada para fatores de confusão. Resultados: De 111 pacientes convidados, oitenta completaram a avaliação neuropsicológica, 56 realizaram RM, tendo sido incluídos no estudo. A média de idade foi de 56,3 ± 8,3 anos e 51,8% (n = 29) apresentavam MoCA alterado. Quando comparado ao grupo MoCA normal, o grupo MoCA alterado apresentou níveis mais elevados de IL-6 e IL-17. Não houve correlação entre MoCA alterado com TFGe nem com anormalidades na RM. Nos modelos ajustados, a IL-6 foi preditor independente do MoCA alterado Conclusão: O CCL avaliado pelo MoCA foi prevalente em pacientes com DRC pré-dialítica, associou-se com inflamação e não apresentou correlação com alterações da RM.

Optical coherence tomography in neurodegenerative disorders.

BACKGROUND: Structural imaging of the brain is the most widely used diagnostic tool for investigating neurodegenerative diseases. More advanced structural imaging techniques have been applied to early or prodromic phases, but they are expensive and not widely available. Therefore, it is highly desirable to search for noninvasive, easily accessible, low-cost clinical biomarkers suitable for large-scale population screening, in order to focus on making diagnoses at the earliest stages of the disease. In this scenario, imaging studies focusing on the structures of the retina have increasingly been used for evaluating neurodegenerative diseases. The retina shares embryological, histological, biochemical, microvascular and neurotransmitter similarities with the cerebral cortex, thus making it a uniquely promising biomarker for neurodegenerative diseases. Optical coherence tomography is a modern noninvasive imaging technique that provides high-resolution two-dimensional cross-sectional images and quantitative reproducible three-dimensional volumetric measurements of the optic nerve head and retina. This technology is widely used in ophthalmology practice for diagnosing and following up several eye diseases, such as glaucoma, diabetic retinopathy and age-related macular degeneration. Its clinical impact on neurodegenerative diseases has raised enormous interest over recent years, as several clinical studies have demonstrated that these diseases give rise to reduced thickness of the inner retinal nerve fiber layer, mainly composed of retinal ganglion cells and their axons. In this review, we aimed to address the clinical utility of optical coherence tomography for diagnosing and evaluating different neurodegenerative diseases, to show the potential of this noninvasive and easily accessible method.

Cross-sectional assessment of mild cognitive impairment in pre-dialysis chronic kidney disease and its association with inflammation and changes seen on MRI: what the eyes cannot see.

INTRODUCTION: Mild cognitive impairment (MCI) is a prevalent and underdiagnosed condition in chronic kidney disease (CKD), that shares common pathophysiological factors such as chronic inflammation. OBJECTIVE: To evaluate the association of MCI in CKD stages 1-5 using inflammatory markers and changes by magnetic resonance imaging (MRI). PATIENTS AND METHODS: Cross-sectional study in adult patients with pre-dialysis CKD. MCI was assessed by the Montreal Cognitive Assessment (MoCA) and the estimated glomerular filtration rate (eGFR) by the Chronic Kidney Disease Epidemiology Collaboration equation. Sociodemographic and clinical data were collected from medical records. The cytokines IL-4, IL-6, IL-17, TNF-α and hs-CRP were determined. Brain MRI was performed in a 1.5 Tesla device, without paramagnetic contrast. A descriptive analysis followed by a comparison of abnormal versus normal MoCA scores among all studied variables. A linear regression analysis was performed using MoCA as a dependent variable, adjusted for confounding factors. RESULTS: Of 111 invited patients, eighty completed the neuropsychological assessment and 56 underwent MRI, and were included in the study. Mean age was 56.3 ± 8.3 years and 51.8% (n = 29) had altered MoCA. When compared to the group with normal MoCA, the group with altered MoCA had higher levels of IL-6 and IL-17. There was no correlation between altered MoCA with eGFR or with MRI abnormalities. CONCLUSÃO: MCI assessed by MoCA was prevalent in patients with pre-dialysis CKD, it was associated with inflammation and showed no correlation with MRI changes.

Optical coherence tomography in neurodegenerative disorders / Tomografia de coerência óptica em doenças neurodegenerativas

ABSTRACT Structural imaging of the brain is the most widely used diagnostic tool for investigating neurodegenerative diseases. More advanced structural imaging techniques have been applied to early or prodromic phases, but they are expensive and not widely available. Therefore, it is highly desirable to search for noninvasive, easily accessible, low-cost clinical biomarkers suitable for large-scale population screening, in order to focus on making diagnoses at the earliest stages of the disease. In this scenario, imaging studies focusing on the structures of the retina have increasingly been used for evaluating neurodegenerative diseases. The retina shares embryological, histological, biochemical, microvascular and neurotransmitter similarities with the cerebral cortex, thus making it a uniquely promising biomarker for neurodegenerative diseases. Optical coherence tomography is a modern noninvasive imaging technique that provides high-resolution two-dimensional cross-sectional images and quantitative reproducible three-dimensional volumetric measurements of the optic nerve head and retina. This technology is widely used in ophthalmology practice for diagnosing and following up several eye diseases, such as glaucoma, diabetic retinopathy and age-related macular degeneration. Its clinical impact on neurodegenerative diseases has raised enormous interest over recent years, as several clinical studies have demonstrated that these diseases give rise to reduced thickness of the inner retinal nerve fiber layer, mainly composed of retinal ganglion cells and their axons. In this review, we aimed to address the clinical utility of optical coherence tomography for diagnosing and evaluating different neurodegenerative diseases, to show the potential of this noninvasive and easily accessible method.

RESUMO A avaliação estrutural do cérebro, feita por meio dos exames de neuroimagem, é a forma mais utilizada de ferramenta diagnóstica e de acompanhamento das doenças neurodegenerativas. Técnicas de imagem mais sofisticadas podem ser necessárias especialmente nas fases mais precoces, antes mesmo do surgimento de quaisquer sintomas, porém costumam ser caras e pouco acessíveis. Sendo assim, é de fundamental importância a busca de biomarcadores não invasivos, de fácil acesso e baixo custo, que possam ser utilizados para rastreio populacional e diagnóstico mais precoce. Nesse cenário, o número de estudos com ênfase em técnicas de imagem para avaliação estrutural da retina em pacientes com doenças neurodegenerativas tem aumentado nos últimos anos. A retina apresenta similaridade embriológica, histológica, bioquímica, microvascular e neurotransmissora com o córtex cerebral, tornando-se assim um biomarcador único e promissor nas doenças neurodegenerativas. A tomografia de coerência óptica é uma moderna técnica de imagem não invasiva que gera imagens seccionais bidimensionais de alta resolução e medidas volumétricas tridimensionais reprodutivas do disco óptico e da mácula. Essa tecnologia é amplamente utilizada na prática oftalmológica para o diagnóstico e o seguimento de diversas doenças oculares, como glaucoma, retinopatia diabética e degeneração macular relacionada à idade. A redução da espessura da camada de fibras nervosas da retina e das camadas de células ganglionares em pacientes com doenças neurodegenerativas foi demonstrada em diversos estudos clínicos nos últimos anos. Nesta revisão, abordamos as principais aplicações clínicas da tomografia de coerência óptica nas doenças neurodegenerativas e discutimos o seu papel como potencial biomarcador nessas afecções.

Relato de experiência: Dia Mundial do Acidente Vascular Cerebral / Experience report: World Stroke Day

Introdução: O Acidente Vascular Cerebral (AVC) é uma das maiores causas de morte e incapacidade adquirida em todo o mundo. Além da alta mortalidade, o AVC é um importante causador de déficits neurológicos irreversíveis que necessitam de reabilitação, sendo que aproximadamente 70% dos pacientes não retomarão ao seu trabalho e 30% necessitarão de auxílio para caminhar. Entender o perfil epidemiológico e a contribuição de cada fator de risco é essencial para estabelecer políticas locais específicas para diminuir a incidência da doença e prevalência de complicações que ocorrem devido ao AVC, tanto para o bem-estar a curto e a longo prazo da população. A prevenção pode ser feita em até 90% dos casos de AVC, visto que estes podem ser atribuídos a fatores de risco modificáveis. Objetivo: Conscientizar e orientar a população da cidade de Juiz de Fora, Minas Gerais acerca dos fatores de risco modificáveis do AVC e, consequentemente, sobre sua prevenção. Relato de experiência: No mês de outubro de 2018 foram realizadas palestras educativas e orientações a respeito do AVC e seus fatores de risco. Além disso, os pacientes do serviço de Neurologia, seus acompanhantes e transeuntes locais tiveram dois dos fatores de risco modificáveis associados ao AVC avaliados: a pressão arterial sistêmica e a circunferência abdominal. Aqueles com alterações foram orientados e encaminhados a procurar um serviço específico. Conclusão: A educação da população sobre as formas de prevenção de doenças cardiovasculares, em especial o acidente vascular cerebral, que é uma doença conhecida por apresentar tantos fatores causais modificáveis, é essencial para evitar o aumento da incidência dessas patologias tão prevalentes no país.

Introduction: Stroke is one of the most prevalent causes of death and acquired inability all over the world. Besides the high rates of mortality, stroke is an important cause of neurologic deficits that will need rehabilitee, since 70% of the patients will not come back for their work and 30% will need help to walk. Understand the epidemiology profile and the contribution of any risk factor is essential to establish specific local politics in order to lower the incidence and complication rates, not only in short term but also in long term. Prevention can be made at 90% cases of stroke, since these cases are attributed to modifiable risk factors. Objective: Guide and alert Juiz de Fora's population about changeable risk factors and prevention of stroke. Experience report: During the final week of October we made educative speeches and offer some guidance about stroke and his modifiable risk factors. Furthermore, the neurology patients, their companions and local people, had their blood pressure assessed, as so as their abdominal circumference. Those with some alteration were guided to look for specific medical support. Conclusion: Education about cardiovascular diseases prevention, in special stroke, which is known for having so many modifiable risk factors, is essential to avoid the incidence of these pathology to increase.

The role of optical coherence tomography in Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the most common cause of dementia and its incidence is increasing worldwide along with population aging. Previous clinical and histologic studies suggest that the neurodegenerative process, which affects the brain, may also affect the retina of AD patients. MAIN BODY: Optical coherence tomography (OCT) is a non-invasive technology that acquires cross-sectional images of retinal structures allowing neural fundus integrity assessment. Several previous studies demonstrated that both peripapillary retinal nerve fiber layer and macular thickness measurements assessed by OCT were able to detect neuronal loss in AD. Moreover, recent advances in OCT technology, have allowed substantial enhancement in ultrastructural evaluation of the macula, enabling the assessment not only of full-thickness retinal measurements but also of inner retinal layers, which seems to be a promising approach, mainly regarding the assessment of retinal ganglion cell layer impairment in AD patients. Furthermore, retinal neuronal loss seems to correlate with cognitive impairment in AD, reinforcing the promising role of OCT in the clinical evaluation of these patients. CONCLUSION: The purpose of this article is to review the main findings on OCT in AD patients, to discuss the role of this important diagnostic tool in these patients and how OCT technology may be useful in understanding morphological retinal changes in AD.

Montreal Cognitive Assessment (MoCA) screening mild cognitive impairment in patients with chronic kidney disease (CKD) pre-dialysis.

INTRODUCTION: Individuals with chronic kidney disease (CKD) are at higher risk of developing cognitive impairment (CI), initially mild (MCI), potentially identifiable, but still poorly diagnosed and treated. The Montreal Cognitive Assessment (MoCA) has been indicated for MCI screening in CKD. OBJECTIVE: To assess MCI in patients with CKD not yet on dialysis. METHODS: Study conducted in 72 non-elderly subjects with pre-dialysis CKD. The neuropsychological assessment included: The global cognitive assessment test MoCA; the clock drawing (CD); the digit span forward (DSF) and reverse (DSR); phonemic verbal (VF) fluency (FAS) and semantics (animals); the fist-edge-palm (FEP); and the memory 10 pictures. RESULTS: The average age of the participants was 56.74 ± 7.63 years, with predominance of male sex (55.6%), mainly with ≥ 4 years of education (84.3%), with CKD cathegories 1, 2 and 3a and 3b (67.6%), hypertension (93.1%) and diabetes mellitus (52.1%). MCI (MoCA ≤ 24) was observed in 73.6% of the patients. We did not find association among MCI with demographic and clinical variables, but a tendency to association with age (p = 0.07), educational level (p= 0.06) and diabetes (0.06). The executive function tests CD, DS-reverse and FEP, individually were able to identify CI with good sensibility and negative predictive value compared to MoCA and together, showed the same capability to identify MCI when compared to MoCA. CONCLUSION: The MCI is common in non-elderly patients with CKD not yet on dialysis. Together, the CD, DSR and FEP showed similar performance in identify MCI in this population when compared to MoCA, suggesting impairment of executive functions.

Macular Thickness Measurements with Frequency Domain-OCT for Quantification of Retinal Neural Loss and its Correlation with Cognitive Impairment in Alzheimer's Disease.

PURPOSE: To evaluate the ability of frequency domain optical coherence tomography (fd-OCT) to estimate retinal neural loss in eyes with Alzheimer's disease (AD). We also verified the existence of a correlation between AD-related cognitive impairment and macular and peripapillary retinal nerve fiber layer (RNFL) thickness measurements. METHODS: fd-OCT scans were obtained from 45 eyes of 24 patients with AD and 48 control eyes. Peripapillary RNFL, macular full-thickness and segmented inner macular thickness parameters were calculated. The inner macular parameters included macular retinal nerve fiber layer (mRNFL) thickness, ganglion cell layer (GCL) plus inner plexiform layer thickness (GCL+), and RNFL plus GCL+ thickness (GCL++). The Mini-Mental State Examination (MMSE) was used to assess cognition in all subjects. The two groups were compared and the relationship between MMSE scores and fd-OCT measurements was verified. RESULTS: Average, superior and inferior quadrant RNFL thickness parameters and all but one of the nine full-thickness macular measurements were significantly reduced in AD patients compared to controls. The segmented layers, GCL+ and GCL++ were significantly reduced in AD eyes. A significant correlation was found between most fd-OCT parameters (especially macular thickness measurements) and MMSE scores. CONCLUSIONS: Most fd-OCT peripapillary RNFL and macular full-thickness and segmented inner retinal layers parameters were reduced in AD eyes compared to controls. Moreover, neuronal loss, especially as reflected in macular parameters, correlated well with cognitive impairment in AD. Our results suggest that fd-OCT could be a potentially useful diagnostic tool in the evaluation and follow-up of AD patients.

Montreal Cognitive Assessment (MoCA) no rastreio de comprometimento cognitivo leve (CCL) em pacientes com doença renal crônica (DRC) pré-dialítica / Montreal Cognitive Assessment (MoCA) screening mild cognitive impairment in patients with chronic kidney disease (CKD) pre-dialysis

Resumo Introdução: Indivíduos com doença renal crônica (DRC) têm grande risco de desenvolver comprometimento cognitivo (CC), inicialmente leve (CCL), passível de identificação, mas ainda subdiagnosticado e subtratado. O Montreal Cognitive Assessment (MoCA) vem sendo indicado para rastreio de CCL na DRC. Objetivo: Avaliar o CCL em indivíduos com DRC pré-dialítica. Métodos: O estudo foi realizado em 72 indivíduos, não idosos, com DRC nos estágios pré-dialíticos. A avaliação neuropsicológica incluiu: o teste de cognição global MoCA; o teste do relógio (TDR); o Digit Span ordem direta (DOD) e inversa (DOI); o teste de fluência verbal (FV), fonêmica (FAS) e semântica (animais); o punho-borda-mão (PBM); e de memória 10 figuras. Resultados: A média de idade dos participantes foi de 56,74 ± 7,63 anos, com predominância de homens (55,6%), com escolaridade ≥ 4 anos (84,3%), a maioria com DRC 1, 2 e 3a e 3b (67,6%), hipertensa (93,1%) e diabética (52,1%). O CC (MoCA ≤ 24) foi observado em 73,6% dos usuários. Não encontramos associação das variáveis demográficas e clínicas com CC, mas tendência de associação com a idade (p = 0,07), com a escolaridade (p = 0,06) e com o DM (0,06). Os testes de função executiva, TDR, DOI e PBM, isoladamente, apresentaram boa sensibilidade e valor preditivo negativo comparados ao MoCA para a identificação de CC e, em conjunto, foram capazes de predizer o resultado do MoCA. Conclusão: O CCL é frequente em usuários não idosos com DRC pré-dialítica. O TDR, DOI e PBM associados são equivalentes ao MoCA na identificação do CC nessa população, sugerindo comprometimento de funções executivas.

Abstract Introduction: Individuals with chronic kidney disease (CKD) are at higher risk of developing cognitive impairment (CI), initially mild (MCI), potentially identifiable, but still poorly diagnosed and treated. The Montreal Cognitive Assessment (MoCA) has been indicated for MCI screening in CKD. Objective: To assess MCI in patients with CKD not yet on dialysis. Methods: Study conducted in 72 non-elderly subjects with pre-dialysis CKD. The neuropsychological assessment included: The global cognitive assessment test MoCA; the clock drawing (CD); the digit span forward (DSF) and reverse (DSR); phonemic verbal (VF) fluency (FAS) and semantics (animals); the fist-edge-palm (FEP); and the memory 10 pictures. Results: The average age of the participants was 56.74 ± 7.63 years, with predominance of male sex (55.6%), mainly with ≥ 4 years of education (84.3%), with CKD cathegories 1, 2 and 3a and 3b (67.6%), hypertension (93.1%) and diabetes mellitus (52.1%). MCI (MoCA ≤ 24) was observed in 73.6% of the patients. We did not find association among MCI with demographic and clinical variables, but a tendency to association with age (p = 0.07), educational level (p= 0.06) and diabetes (0.06). The executive function tests CD, DS-reverse and FEP, individually were able to identify CI with good sensibility and negative predictive value compared to MoCA and together, showed the same capability to identify MCI when compared to MoCA. Conclusion: The MCI is common in non-elderly patients with CKD not yet on dialysis. Together, the CD, DSR and FEP showed similar performance in identify MCI in this population when compared to MoCA, suggesting impairment of executive functions.