Economic Burden of Huntington's Disease: Analysis from a Brazilian Tertiary Care Perspective.

Background: Huntington's disease (HD) exerts significant impacts on individuals and families worldwide. Nevertheless, data on its economic burden in Brazil are scarce, revealing a critical gap in understanding the associated healthcare costs. Objective: This study was conducted at a tertiary neurology outpatient clinic in Brazil with the aim of assessing annual healthcare service utilization and associated costs for HD patients. Methods: We conducted a cross-sectional observational study involving 34 HD patients. A structured questionnaire was applied to collect data on direct medical costs (outpatient services, medications), non-medical direct costs (complementary therapies, mobility aids, home adaptations), and indirect costs (lost productivity, caregiver costs, government benefits) over one year. Results: Significant economic impacts were observed, with average annual direct medical costs of $4686.82 per HD patient. Non-medical direct and indirect costs increased the financial burden, highlighting extensive resource utilization beyond healthcare services. Thirty-three out of 34 HD patients were unemployed or retired, and 16 relied on government benefits, reflecting broader socioeconomic implications. Despite the dataset's limitations, it provides crucial insights into the economic impact of HD on patients and the Brazilian public health system. Conclusions: The findings underscore the urgent need for a more comprehensive evaluation of the costs to inform governmental policies related to HD. Future research is needed to expand the data pool and develop a nuanced understanding of the economic burdens of HD to help formulate effective healthcare strategies for patients.

Clinical, neuroimaging and genetic findings in Brazilian patients with neurodegeneration with brain iron accumulation.

Neurodegeneration with brain iron accumulation (NBIA) encompasses a clinically and genetically heterogeneous group of rare disorders. Here, we report clinical, neuroimaging and genetic studies in twenty three Brazilian NBIA patients. In thirteen subjects, deleterious variants were detected in known NBIA-causing genes (PANK2, PLA2G6, C9ORF12, WDR45 and FA2H), including previously unreported variants in PANK2 and PLA2G6. Two patients carried rare, likely pathogenic variants in genes not previously associated with NBIA: KMT2A c.11785A > C (p.Ile3929Leu), and TIMM8A c.127T > C (p.Cys43Arg), suggesting an expansion of their associated phenotypes to include NBIA. In eight patients the etiology remains unsolved, suggesting variants undetectable by the adopted methods, or the existence of additional NBIA-causing genes.

Task-related brain activity in upper limb dystonia revealed by simultaneous fNIRS and EEG.

OBJECTIVE: The aim of this study was to explore differences in brain activity and connectivity using simultaneous electroencephalography and near-infrared spectroscopy in patients with focal dystonia during handwriting and finger-tapping tasks. METHODS: Patients with idiopathic right upper limb focal dystonia and controls were assessed by simultaneous near-infrared spectroscopy and electroencephalography during the writing and finger-tapping tasks in terms of the mu-alpha, mu-beta, beta and low gamma power and effective connectivity, as well as relative changes in oxyhemoglobin (oxy-Hb) and deoxyhemoglobin using a channel-wise approach with a mixed-effect model. RESULTS: Patients exhibited higher oxy-Hb levels in the right and left motor cortex and supplementary motor area during writing, but lower oxy-Hb levels in the left sensorimotor and bilateral somatosensory area during finger-tapping compared to controls. During writing, patients showed increased low gamma power in the bilateral sensorimotor cortex and less mu-beta and beta attenuation compared to controls. Additionally, patients had reduced connectivity between the supplementary motor area and the left sensorimotor cortex during writing. No differences were observed in terms of effective connectivity in either task. Finally, patients failed to attenuate the mu-alpha, mu-beta, and beta rhythms during the finger-tapping task. CONCLUSIONS: Cortical blood flow and EEG spectral power differ between controls and dystonia patients, depending on the task. Writing increased blood flow and altered connectivity in dystonia patients, and it also decreased slow-band attenuation. Finger-tapping decreased blood flow and slow-band attenuation. SIGNIFICANCE: Simultaneous fNIRS and EEG may show relevant information regarding brain dynamics in movement disorders patients in unconstrained environments.

Floor and ceiling effects on the Montreal Cognitive Assessment in patients with Parkinson's disease in Brazil.

Parkinson's disease (PD) is a common neurodegenerative disease associated with cognitive impairment. The Montreal Cognitive Assessment (MoCA) has been used as a recommended global cognition scale for patients with PD, but there are some concerns about its application, partially due to the floor and ceiling effects. Objective: To explore the floor and ceiling effects on the MoCA in patients with PD in Brazil. Methods: Cross-sectional study with data from patients with PD from five Brazilian Movement Disorders Clinics, excluding individuals with a possible diagnosis of dementia. We analyzed the total score of the MoCA, as well as its seven cognitive domains. The floor and ceiling effects were evaluated for the total MoCA score and domains. Multivariate analyses were performed to detect factors associated with floor and ceiling effects. Results: We evaluated data from 366 patients with PD and approximately 19% of individuals had less than five years of education. For the total MoCA score, there was no floor or ceiling effect. There was a floor effect in the abstraction and delayed memory recall domains in 20% of our sample. The ceiling effect was demonstrated in all domains (80.8% more common in naming and 89% orientation), except delayed recall. Education was the main factor associated with the floor and ceiling effects, independent of region, sex, age at evaluation, and disease duration. Conclusion: The floor and ceiling effects are present in specific domains of the MoCA in Brazil, with a strong impact on education. Further adaptations of the MoCA structure for underrepresented populations may reduce these negative effects.

A doença de Parkinson (DP) é uma doença neurodegenerativa comum associada ao declínio cognitivo. A Avaliação Cognitiva de Montreal (Montreal Cognitive Assessment ­ MoCA) tem sido usada como uma escala de cognição global recomendada para pacientes com DP, mas existem algumas preocupações sobre sua aplicação, em parte pelos efeitos solo e teto. Objetivo: Explorar os efeitos solo e teto na MoCA em pacientes com DP no Brasil. Métodos: Estudo transversal com dados de pacientes com DP oriundos de cinco Clínicas de Distúrbios de Movimento no Brasil, excluindo-se pessoas com possível diagnóstico de demência. Nós analisamos a pontuação total da MoCA, assim como a de seus sete domínios cognitivos. Os efeitos solo e teto foram avaliados para a pontuação total da MoCA e seus domínios. Foram feitas análises multivariadas para a detecção de fatores associados os efeitos solo e teto. Resultados: Nós avaliamos dados de 366 pacientes com DP, e aproximadamente 19% das pessoas tinham menos que cinco anos de escolaridade. Para a pontuação total do MoCA, não houve efeito solo ou teto. Houve efeito solo nos domínios abstração e memória de evocação tardia em 20% de nossa amostra. O efeito teto foi demonstrado em todos os domínios (80,8% mais comum em nomeação e 89% orientação), com exceção de memória de evocação tardia. A educação foi o principal fator associado aos efeitos solo e teto, independentemente de região, sexo, idade na avaliação e duração da doença. Conclusão: Os efeitos solo e teto estão presentes em domínios específicos da MoCA no Brasil, com forte impacto da educação. Adaptações adicionais à estrutura da MoCA para populações vulneráveis podem reduzir esses efeitos negativos.

History of high household pesticide use and Parkinson's disease in Brazil.

The prevalence of Parkinson's disease (PD) is growing worldwide and household pesticides exposure may be related to this phenomenon. We showed that individuals with high exposure to household pesticides have two times more risk of developing PD. Household pesticide exposure did not impact age at PD onset.

Blepharospasm Patients after Botulinum Toxin - Sleep Approach.

Background Blepharospasm is a focal dystonia that affects the orbicularis oculi muscles. The interest in nonmotor symptoms is due to their impact on quality of life. Objective We evaluated the frequency of sleep disorders and circadian rhythm in a sample of Brazilian blepharospasm patients. Methods A total of 51 patients, who met the clinical criteria for blepharospasm, evaluated by 2 specialists in movement disorders, were recruited from the outpatient clinic for movement disorders of two reference centers in the city of São Paulo: Universidade Federal de São Paulo and Hospital do Servidor Público do Estado de São Paulo. The selected 13 patients were evaluated from 13 days before to 13 days after using botulinum toxin. They were interviewed, underwent physical examination and actigraphy, and completed sleep diaries. Results After using botulinum toxin, the group that reported sleep improvement exhibited a 50% decrease in sleep latency. There was no change in restless leg syndrome or circadian rhythm. Patients who reported no sleep improvement after using botulinum toxin presented poorer synchronization of the light-dark cycle. Conclusion Blepharospasm patients have poor sleep quality. About 50% of the patients had sleep improvement after using botulinum toxin. The synchronization of the light-dark cycle should be influenced by this finding.

Neurological symptoms and comorbidity profile of hospitalized patients with COVID-19.

BACKGROUND: The neurological manifestations in COVID-19 adversely impact acute illness and post-disease quality of life. Limited data exist regarding the association of neurological symptoms and comorbid individuals. OBJECTIVE: To assess neurological symptoms in hospitalized patients with acute COVID-19 and multicomorbidities. METHODS: Between June 2020 and July 2020, inpatients aged 18 or older, with laboratory-confirmed COVID-19, admitted to the Hospital São Paulo (Federal University of São Paulo), a tertiary referral center for high complexity cases, were questioned about neurological symptoms. The Composite Autonomic Symptom Score 31 (COMPASS-31) questionnaire was used. The data were analyzed as a whole and whether subjective olfactory dysfunction was present or not. RESULTS: The mean age of the sample was 55 ± 15.12 years, and 58 patients were male. The neurological symptoms were mostly xerostomia (71%), ageusia/hypogeusia (50%), orthostatic intolerance (49%), anosmia/hyposmia (44%), myalgia (31%), dizziness (24%), xerophthalmia (20%), impaired consciousness (18%), and headache (16%). Furthermore, 91% of the patients had a premorbidity. The 44 patients with subjective olfactory dysfunction were more likely to have hypertension, diabetes, weakness, shortness of breath, ageusia/hypogeusia, dizziness, orthostatic intolerance, and xerophthalmia. The COMPASS-31 score was higher than that of previously published controls (14.85 ± 12.06 vs. 8.9 ± 8.7). The frequency of orthostatic intolerance was 49% in sample and 63.6% in those with subjective olfactory dysfunction (2.9-fold higher risk compared to those without). CONCLUSION: A total of 80% of inpatients with multimorbidity and acute COVID-19 had neurological symptoms. Chemical sense and autonomic symptoms stood out. Orthostatic intolerance occurred in around two-thirds of the patients with anosmia/hyposmia. Hypertension and diabetes were common, mainly in those with anosmia/hyposmia.

ANTECEDENTES: As manifestações neurológicas na COVID-19 impactam adversamente na enfermidade aguda e na qualidade de vida após a doença. Dados limitados existem em relação a associação de sintomas neurológicos e indivíduos com comorbidades. OBJETIVO: Avaliar os sintomas neurológicos em pacientes de hospitalizados com COVID-19 aguda e múltiplas comorbidades. MéTODOS: Entre junho e julho de 2020, pacientes de hospitais com idade 18 anos ou acima e COVID-19 laboratorialmente confirmada, admitidos no Hospital São Paulo (Universidade Federal de São Paulo), um centro de referência terciário para casos de alta complexidade, foram perguntados sobre sintomas neurológicos. O questionário Pontuação composta de sintoma autonômico (COMPASS-31) foi usado. Os dados foram analisados no geral e se a disfunção olfatória subjetiva estava presente ou não. RESULTADOS: A média de idade da amostra foi 55 ± 15.12 anos. 58 pacientes eram homens. Os sintomas neurológicos foram principalmente xerostomia (71%), ageusia/hipogeusia (50%), intolerância ortostática (49%), anosmia/hiposmia (44%), mialgia (31%), tontura (24%), xeroftalmia (20%), comprometimento na consciência (18%) e cefaleia (16%). Além disso, 91% dos pacientes tinham uma pré-morbidade. Os 44 pacientes com disfunção olfatória tinham maior chance de ter hipertensão, diabetes, fraqueza, falta de ar, ageusia/hipogeusia, tontura, intolerância ortostática e xeroftalmia. A pontuação do COMPASS-31 foi maior do que a de controles previamente publicados (14,85 ± 12,06 vs. 8,9 ± 8,7). A frequência de intolerância ortostática foi 49% na amostra e 63,6% naqueles com disfunção olfatória subjetiva (risco 2.9 vezes maior comparado com os sem). CONCLUSãO: Um total de 80% dos pacientes hospitalizados com múltiplas morbidades e COVID-19 aguda tinham sintomas neurológicos. Os sintomas do sentido químico e autonômicos se destacaram. A intolerância ortostática ocorreu em cerca de dois terços dos pacientes com anosmia/hiposmia. A hipertensão e o diabetes foram comuns, principalmente naqueles com anosmia/hiposmia.

Neurological symptoms and comorbidity profile of hospitalized patients with COVID-19 / Sintomas neurológicos e perfil de comorbidades de pacientes hospitalizados com COVID-19

Abstract Background The neurological manifestations in COVID-19 adversely impact acute illness and post-disease quality of life. Limited data exist regarding the association of neurological symptoms and comorbid individuals. Objective To assess neurological symptoms in hospitalized patients with acute COVID-19 and multicomorbidities. Methods Between June 2020 and July 2020, inpatients aged 18 or older, with laboratory-confirmed COVID-19, admitted to the Hospital São Paulo (Federal University of São Paulo), a tertiary referral center for high complexity cases, were questioned about neurological symptoms. The Composite Autonomic Symptom Score 31 (COMPASS-31) questionnaire was used. The data were analyzed as a whole and whether subjective olfactory dysfunction was present or not. Results The mean age of the sample was 55 ± 15.12 years, and 58 patients were male. The neurological symptoms were mostly xerostomia (71%), ageusia/hypogeusia (50%), orthostatic intolerance (49%), anosmia/hyposmia (44%), myalgia (31%), dizziness (24%), xerophthalmia (20%), impaired consciousness (18%), and headache (16%). Furthermore, 91% of the patients had a premorbidity. The 44 patients with subjective olfactory dysfunction were more likely to have hypertension, diabetes, weakness, shortness of breath, ageusia/hypogeusia, dizziness, orthostatic intolerance, and xerophthalmia. The COMPASS-31 score was higher than that of previously published controls (14.85 ± 12.06 vs. 8.9 ± 8.7). The frequency of orthostatic intolerance was 49% in sample and 63.6% in those with subjective olfactory dysfunction (2.9-fold higher risk compared to those without). Conclusion A total of 80% of inpatients with multimorbidity and acute COVID-19 had neurological symptoms. Chemical sense and autonomic symptoms stood out. Orthostatic intolerance occurred in around two-thirds of the patients with anosmia/hyposmia. Hypertension and diabetes were common, mainly in those with anosmia/hyposmia.

Resumo Antecedentes As manifestações neurológicas na COVID-19 impactam adversamente na enfermidade aguda e na qualidade de vida após a doença. Dados limitados existem em relação a associação de sintomas neurológicos e indivíduos com comorbidades. Objetivo Avaliar os sintomas neurológicos em pacientes de hospitalizados com COVID-19 aguda e múltiplas comorbidades. Métodos Entre junho e julho de 2020, pacientes de hospitais com idade 18 anos ou acima e COVID-19 laboratorialmente confirmada, admitidos no Hospital São Paulo (Universidade Federal de São Paulo), um centro de referência terciário para casos de alta complexidade, foram perguntados sobre sintomas neurológicos. O questionário Pontuação composta de sintoma autonômico (COMPASS-31) foi usado. Os dados foram analisados no geral e se a disfunção olfatória subjetiva estava presente ou não. Resultados A média de idade da amostra foi 55 ± 15.12 anos. 58 pacientes eram homens. Os sintomas neurológicos foram principalmente xerostomia (71%), ageusia/hipogeusia (50%), intolerância ortostática (49%), anosmia/hiposmia (44%), mialgia (31%), tontura (24%), xeroftalmia (20%), comprometimento na consciência (18%) e cefaleia (16%). Além disso, 91 % dos pacientes tinham uma pré-morbidade. Os 44 pacientes com disfunção olfatória tinham maior chance de ter hipertensão, diabetes, fraqueza, falta de ar, ageusia/hipogeusia, tontura, intolerância ortostática e xeroftalmia. A pontuação do COMPASS-31 foi maior do que a de controles previamente publicados (14,85 ± 12,06 vs. 8,9 ± 8,7). A frequência de intolerância ortostática foi 49% na amostra e 63,6% naqueles com disfunção olfatória subjetiva (risco 2.9 vezes maior comparado com os sem). Conclusão Um total de 80% dos pacientes hospitalizados com múltiplas morbidades e COVID-19 aguda tinham sintomas neurológicos. Os sintomas do sentido químico e autonômicos se destacaram. A intolerância ortostática ocorreu em cerca de dois terços dos pacientes com anosmia/hiposmia. A hipertensão e o diabetes foram comuns, principalmente naqueles com anosmia/hiposmia.

Floor and ceiling effects on the Montreal Cognitive Assessment in patients with Parkinson's disease in Brazil / Efeitos solo e teto na Avaliação Cognitiva de Montreal em pacientes com doença de Parkinson no Brasil

ABSTRACT Parkinson's disease (PD) is a common neurodegenerative disease associated with cognitive impairment. The Montreal Cognitive Assessment (MoCA) has been used as a recommended global cognition scale for patients with PD, but there are some concerns about its application, partially due to the floor and ceiling effects. Objective: To explore the floor and ceiling effects on the MoCA in patients with PD in Brazil. Methods: Cross-sectional study with data from patients with PD from five Brazilian Movement Disorders Clinics, excluding individuals with a possible diagnosis of dementia. We analyzed the total score of the MoCA, as well as its seven cognitive domains. The floor and ceiling effects were evaluated for the total MoCA score and domains. Multivariate analyses were performed to detect factors associated with floor and ceiling effects. Results: We evaluated data from 366 patients with PD and approximately 19% of individuals had less than five years of education. For the total MoCA score, there was no floor or ceiling effect. There was a floor effect in the abstraction and delayed memory recall domains in 20% of our sample. The ceiling effect was demonstrated in all domains (80.8% more common in naming and 89% orientation), except delayed recall. Education was the main factor associated with the floor and ceiling effects, independent of region, sex, age at evaluation, and disease duration. Conclusion: The floor and ceiling effects are present in specific domains of the MoCA in Brazil, with a strong impact on education. Further adaptations of the MoCA structure for underrepresented populations may reduce these negative effects.

RESUMO A doença de Parkinson (DP) é uma doença neurodegenerativa comum associada ao declínio cognitivo. A Avaliação Cognitiva de Montreal (Montreal Cognitive Assessment — MoCA) tem sido usada como uma escala de cognição global recomendada para pacientes com DP, mas existem algumas preocupações sobre sua aplicação, em parte pelos efeitos solo e teto. Objetivo: Explorar os efeitos solo e teto na MoCA em pacientes com DP no Brasil. Métodos: Estudo transversal com dados de pacientes com DP oriundos de cinco Clínicas de Distúrbios de Movimento no Brasil, excluindo-se pessoas com possível diagnóstico de demência. Nós analisamos a pontuação total da MoCA, assim como a de seus sete domínios cognitivos. Os efeitos solo e teto foram avaliados para a pontuação total da MoCA e seus domínios. Foram feitas análises multivariadas para a detecção de fatores associados os efeitos solo e teto. Resultados: Nós avaliamos dados de 366 pacientes com DP, e aproximadamente 19% das pessoas tinham menos que cinco anos de escolaridade. Para a pontuação total do MoCA, não houve efeito solo ou teto. Houve efeito solo nos domínios abstração e memória de evocação tardia em 20% de nossa amostra. O efeito teto foi demonstrado em todos os domínios (80,8% mais comum em nomeação e 89% orientação), com exceção de memória de evocação tardia. A educação foi o principal fator associado aos efeitos solo e teto, independentemente de região, sexo, idade na avaliação e duração da doença. Conclusão: Os efeitos solo e teto estão presentes em domínios específicos da MoCA no Brasil, com forte impacto da educação. Adaptações adicionais à estrutura da MoCA para populações vulneráveis podem reduzir esses efeitos negativos.

Guidelines for Parkinson's disease treatment: consensus from the Movement Disorders Scientific Department of the Brazilian Academy of Neurology - motor symptoms.

The treatment of Parkinson's disease (PD) is challenging, especially since it is considered highly individualized. The Brazilian Academy of Neurology has recognized the need to disseminate knowledge about the management of PD treatment, adapting the best evidence to the Brazilian reality. Thus, the main published treatment guidelines were reviewed based on the recommendations of group from the Movement Disorders Scientific Department of the Brazilian Academy of Neurology.

Guidelines for Parkinson's disease treatment: consensus from the Movement Disorders Scientific Department of the Brazilian Academy of Neurology - motor symptoms / Diretrizes para o tratamento da doença de Parkinson: consenso do Departamento Científico de Transtornos do Movimento da Academia Brasileira de Neurologia - sintomas motores

ABSTRACT The treatment of Parkinson's disease (PD) is challenging, especially since it is considered highly individualized. The Brazilian Academy of Neurology has recognized the need to disseminate knowledge about the management of PD treatment, adapting the best evidence to the Brazilian reality. Thus, the main published treatment guidelines were reviewed based on the recommendations of group from the Movement Disorders Scientific Department of the Brazilian Academy of Neurology.

Resumo O tratamento da doença de Parkinson (DP) constitui um desafio, especialmente por ser considerado muito individualizado. A Academia Brasileira de Neurologia (ABN) identificou a necessidade de disseminar o conhecimento sobre o manejo do tratamento da DP, adaptando as melhores evidências à realidade brasileira. Assim, foi realizada uma revisão sobre as principais orientações de tratamento publicadas, baseada nas recomendações elaboradas por um grupo de especialistas em transtornos do movimento do departamento científico da ABN.

High prevalence of self-reported non-motor symptoms and lack of correlation with motor severity in adult patients with idiopathic isolated dystonia.

BACKGROUND: Although abnormal movements and postures are the hallmark of dystonia, non-motor symptoms (NMS) are common and negatively affect quality of life. OBJECTIVES: The aim of this study was to screen dystonia patients for NMS and analyze their association with clinical parameters, including motor disability. METHODS: Adult patients with idiopathic isolated dystonia were interviewed and examined. Dystonia severity was evaluated with the Fahn-Marsden Dystonia Rating Scale and the presence of NMS was assessed using a list of 29 complaints. RESULTS: A hundred and two patients (63.7% female) were enrolled. Dystonia began after 20 years of age in 61.8% and was focal or segmental in 82.8% of patients. Only eight patients (7.8%) had no NMS and 59.8% reported more than five. The most prevalent NMS were pain (72.5%) and anxiety (63.7%), followed by difficulty recalling information (44.1%), sadness/anhedonia (41.2%), and difficulty falling asleep (38.2%). No correlation was found between the total number of NMS and dystonia severity (p = 0.18) or regular botulinum toxin use (p = 0.66). The majority of NMS domains correlated with each other. CONCLUSIONS: Our results confirm a high prevalence of NMS among dystonia patients, even in those with mild motor disability. The pathophysiology of NMS in dystonia remains to be completely understood.

Tracing the Distribution of European Lactase Persistence Genotypes Along the Americas.

In adulthood, the ability to digest lactose, the main sugar present in milk of mammals, is a phenotype (lactase persistence) observed in historically herder populations, mainly Northern Europeans, Eastern Africans, and Middle Eastern nomads. As the -13910∗T allele in the MCM6 gene is the most well-characterized allele responsible for the lactase persistence phenotype, the -13910C > T (rs4988235) polymorphism is commonly evaluated in lactase persistence studies. Lactase non-persistent adults may develop symptoms of lactose intolerance when consuming dairy products. In the Americas, there is no evidence of the consumption of these products until the arrival of Europeans. However, several American countries' dietary guidelines recommend consuming dairy for adequate human nutrition and health promotion. Considering the extensive use of dairy and the complex ancestry of Pan-American admixed populations, we studied the distribution of -13910C > T lactase persistence genotypes and its flanking haplotypes of European origin in 7,428 individuals from several Pan-American admixed populations. We found that the -13910∗T allele frequency in Pan-American admixed populations is directly correlated with allele frequency of the European sources. Moreover, we did not observe any overrepresentation of European haplotypes in the -13910C > T flanking region, suggesting no selective pressure after admixture in the Americas. Finally, considering the dominant effect of the -13910∗T allele, our results indicate that Pan-American admixed populations are likely to have higher frequency of lactose intolerance, suggesting that general dietary guidelines deserve further evaluation across the continent.

Genetics of Parkinson's disease in Brazil: a systematic review of monogenic forms.

BACKGROUND: Increasing numbers of mutations causing monogenic forms of Parkinson's disease (PD) have been described, mostly among patients in Europe and North America. Since genetic architecture varies between different populations, studying the specific genetic profile of Brazilian patients is essential for improving genetic counseling and for selecting patients for clinical trials. OBJECTIVE: We conducted a systematic review to identify genetic studies on Brazilian patients and to set a background for future studies on monogenic forms of PD in Brazil. METHODS: We searched MEDLINE, EMBASE and Web of Science from inception to December 2019 using terms for "Parkinson's disease", "genetics" and "Brazil". Two independent reviewers extracted the data. For the genes LRRK2 and PRKN, the estimated prevalence was calculated for each study, and a meta-analysis was performed. RESULTS: A total of 32 studies were included, comprising 94 Brazilian patients with PD with a causative mutation, identified from among 2,872 screened patients (3.2%). PRKN mutations were causative of PD in 48 patients out of 576 (8.3%). LRRK2 mutations were identified in 40 out of 1,556 patients (2.5%), and p.G2019S was the most common mutation (2.2%). CONCLUSIONS: PRKN is the most common autosomal recessive cause of PD, and LRRK2 is the most common autosomal dominant form. We observed that there was a lack of robust epidemiological studies on PD genetics in Brazil and, especially, that the diversity of Brazil's population had not been considered.

Characterizing the Genetic Architecture of Parkinson's Disease in Latinos.

OBJECTIVE: This work was undertaken in order to identify Parkinson's disease (PD) risk variants in a Latino cohort, to describe the overlap in the genetic architecture of PD in Latinos compared to European-ancestry subjects, and to increase the diversity in PD genome-wide association (GWAS) data. METHODS: We genotyped and imputed 1,497 PD cases and controls recruited from nine clinical sites across South America. We performed a GWAS using logistic mixed models; variants with a p-value <1 × 10-5 were tested in a replication cohort of 1,234 self-reported Latino PD cases and 439,522 Latino controls from 23andMe, Inc. We also performed an admixture mapping analysis where local ancestry blocks were tested for association with PD status. RESULTS: One locus, SNCA, achieved genome-wide significance (p-value <5 × 10-8 ); rs356182 achieved genome-wide significance in both the discovery and the replication cohorts (discovery, G allele: 1.58 OR, 95% CI 1.35-1.86, p-value 2.48 × 10-8 ; 23andMe, G allele: 1.26 OR, 95% CI 1.16-1.37, p-value 4.55 × 10-8 ). In our admixture mapping analysis, a locus on chromosome 14, containing the gene STXBP6, achieved significance in a joint test of ancestries and in the Native American single-ancestry test (p-value <5 × 10-5 ). A second locus on chromosome 6, containing the gene RPS6KA2, achieved significance in the African single-ancestry test (p-value <5 × 10-5 ). INTERPRETATION: This study demonstrated the importance of the SNCA locus for the etiology of PD in Latinos. By leveraging the demographic history of our cohort via admixture mapping, we identified two potential PD risk loci that merit further study. ANN NEUROL 2021;90:353-365.

What can be expected to be seen in a Neurology ward? Eleven-year experience in a Brazilian university hospital.

BACKGROUND: Neurological disorders are significant causes of morbidity and mortality worldwide. However, data about general neurological inpatient admissions in Brazil is limited. Objective: To investigate the prevalence of neurological disorders according to disease group and lesion site among patients admitted to a general Neurology ward. METHODS: This was an observational and descriptive study. The hospital discharge database for the Neurology ward was surveyed in accordance with the International Classification of Diseases, 10th edition (ICD-10), from September 2008 to October 2019. The final diagnosis was classified into neurological disorder groups and site. RESULTS: Overall, 2,606 clinical neurological patient files were included, with mean length of hospitalization of 16.7 days and a total of 325 readmissions (12.5%). The overall mortality rate in the ward was 3.8% (100 patients). Among all the diagnoses, cerebrovascular disease was the most prevalent (45.8%), followed by inflammatory disorders (22.2%). The brain was the most common lesion site (66.0%), followed by peripheral nerves (10.0%) and meninges and cerebrospinal fluid (7.7%). CONCLUSIONS: The disease pattern upon admission showed that a majority of the cases consisted of cerebrovascular disorders and that the brain was the most frequently affected structure, although we observed that a wide variety of cases were admitted, encompassing all neurological disorders.

What can be expected to be seen in a Neurology ward? Eleven-year experience in a Brazilian university hospital / O que se espera encontrar em uma enfermaria de Neurologia? A experiência de 11 anos em um hospital universitário brasileiro

ABSTRACT Background: Neurological disorders are significant causes of morbidity and mortality worldwide. However, data about general neurological inpatient admissions in Brazil is limited. Objective: To investigate the prevalence of neurological disorders according to disease group and lesion site among patients admitted to a general Neurology ward. Methods: This was an observational and descriptive study. The hospital discharge database for the Neurology ward was surveyed in accordance with the International Classification of Diseases, 10th edition (ICD-10), from September 2008 to October 2019. The final diagnosis was classified into neurological disorder groups and site. Results: Overall, 2,606 clinical neurological patient files were included, with mean length of hospitalization of 16.7 days and a total of 325 readmissions (12.5%). The overall mortality rate in the ward was 3.8% (100 patients). Among all the diagnoses, cerebrovascular disease was the most prevalent (45.8%), followed by inflammatory disorders (22.2%). The brain was the most common lesion site (66.0%), followed by peripheral nerves (10.0%) and meninges and cerebrospinal fluid (7.7%). Conclusions: The disease pattern upon admission showed that a majority of the cases consisted of cerebrovascular disorders and that the brain was the most frequently affected structure, although we observed that a wide variety of cases were admitted, encompassing all neurological disorders.

RESUMO Introdução: As doenças neurológicas representam importante causa de morbidade e mortalidade globalmente, mas informações acerca de internações hospitalares em neurologia no Brasil são limitadas. Objetivo: Investigar a prevalência de admissões neurológicas por grupo de doenças e pela topografia atendidas em uma enfermaria de neurologia geral. Métodos: Estudo observacional e descritivo. Avaliados diagnósticos de saída de acordo com o Código Internacional de Doenças-10 (CID-10) no período de setembro de 2008 a outubro de 2019. Os diagnósticos foram classificados em grupos de doença e por topografia. Resultados: Foram incluídos 2,606 pacientes, com tempo médio de internação de 16,7 dias e um total de 325 (12,5%) readmissões. A mortalidade geral na enfermaria foi de 100 (3,8%) pacientes. A doença cerebrovascular foi mais prevalente (45,8%), seguida das doenças inflamatórias (22,2%). A topografia encefálica foi a mais comum (66,0%), seguida de nervos periféricos (10,0%), meninges e líquido cefalorraquidiano (7,7%). Conclusões: O perfil de doenças observado neste estudo demonstrou maior prevalência das doenças cerebrovasculares e da topografia encefálica, embora uma grande variedade de doenças tenha sido admitida dentro do espectro de doenças neurológicas.

Neuroimaging Assessment of Nigrosome 1 with a Multiecho Gre Magnetic Resonance Sequence in the Differentiation Between Parkinsons Disease from Essential Tremor and Healthy Individuals.

Background and purpose: Parkinsonism is commonly seen in many clinical conditions, and the establishment of its etiology may take many years. The possible development of neuroprotective treatments for Parkinsons disease (PD) in the near future will require correct and early diagnosis. This study aims to analyze the accuracy of a low-cost MRI sequence to differentiate PD from patients with essential tremor (ET) and healthy control (HC) individuals. Material and methods: We recruited 70 individuals with clinical diagnoses of PD (38 patients), ET (11 patients) and healthy volunteers (21 individuals), all of whom underwent 3T MRI multiecho GRE sequence. Two blinded neuroradiologists independently evaluated the presence or absence of nigrosome-1(N1). We considered the unilateral or bilateral absence of nigrosome 1 signal as indicative of PD. Results: The absence of at least one N1 could differentiate with 98% accuracy patients with clinical established PD from healthy controls. The presence of both nigrosomes was 96% accurate as a sign to differentiate PD from ET patients. Conclusion: The 3T MRI with multiecho GRE is a simple and universally available technique and it can be used as a good auxiliary tool to differentiate PD from ET patients and controls.

Motor Cortex Activation During Writing in Focal Upper-Limb Dystonia: An fNIRS Study.

BACKGROUND: Functional imaging studies have associated dystonia with abnormal activation in motor and sensory brain regions. Commonly used techniques such as functional magnetic resonance imaging impose physical constraints, limiting the experimental paradigms. Functional near-infrared spectroscopy (fNIRS) offers a new noninvasive possibility for investigating cortical areas and the neural correlates of complex motor behaviors in unconstrained settings. METHODS: We compared the cortical brain activation of patients with focal upper-limb dystonia and controls during the writing task under naturalistic conditions using fNIRS. The primary motor cortex (M1), the primary somatosensory cortex (S1), and the supplementary motor area were chosen as regions of interest (ROIs) to assess differences in changes in both oxyhemoglobin (oxy-Hb) and deoxyhemoglobin (deoxy-Hb) between groups. RESULTS: Group average activation maps revealed an expected pattern of contralateral recruitment of motor and somatosensory cortices in the control group and a more bilateral pattern of activation in the dystonia group. Between-group comparisons focused on specific ROIs revealed an increased activation of the contralateral M1 and S1 cortices and also of the ipsilateral M1 cortex in patients. CONCLUSIONS: Overactivity of contralateral M1 and S1 in dystonia suggest a reduced specificity of the task-related cortical areas, whereas ipsilateral activation possibly indicates a primary disorder of the motor cortex or an endophenotypic pattern. To our knowledge, this is the first study using fNIRS to assess cortical activity in dystonia during the writing task under natural settings, outlining the potential of this technique for monitoring sensory and motor retraining in dystonia rehabilitation.

Task-related brain activity and functional connectivity in upper limb dystonia: a functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS) study.

Significance: Dystonia is a dynamic and complex disorder. Real-time analysis of brain activity during motor tasks may increase our knowledge on its pathophysiology. Functional near-infrared spectroscopy (fNIRS) is a noninvasive method that enables the measurement of cortical hemodynamic activity in unconstrained environments. Aim: We aimed to explore the feasibility of using fNIRS for the study of task-related brain activity in dystonia. Task-related functional magnetic resonance imaging (fMRI) and resting-state functional connectivity were also analyzed. Approach: Patients with idiopathic right-upper limb dystonia and controls were assessed through nonsimultaneous fMRI and fNIRS during a finger-tapping task. Seed-based connectivity analysis of resting-state fMRI was performed in both groups. Results: The fMRI results suggest nonspecific activation of the cerebellum and occipital lobe in dystonia patients during the finger-tapping task with the affected hand. Moreover, fNIRS data show lower activation in terms of oxyhemoglobin and total hemoglobin in the frontal, ipsilateral cortex, and somatosensory areas during this task. In dystonia, both fMRI and fNIRS data resulted in hypoactivation of the frontal cortex during finger tapping with both hands simultaneously. Resting-state functional connectivity analysis suggests that the cerebellar somatomotor network in dystonia has an increased correlation with the medial prefrontal cortex and the paracingulate gyrus. Conclusions: These data suggest that unbalanced activation of the cerebellum, somatosensory, and frontal cortical areas are associated with dystonia. To our knowledge, this is the first study using fNIRS to explore the pathophysiology of dystonia. We show that fNIRS and fMRI are complementary methods and highlight the potential of fNIRS for the study of dystonia and other movement disorders as it can overcome movement restrictions, enabling experiments in more naturalistic conditions.