ABSTRACT The Argentina-Alzheimer's disease neuroimaging initiative (Arg-ADNI) study is a longitudinal prospective cohort of 50 participants at a single institution in Buenos Aires, Argentina. Longitudinal assessments on a neuropsychological test battery were performed on 15 controls, 24 mild cognitive impairment (MCI) patients and 12 Alzheimer's disease (AD) dementia patients. In our study population, there was a high prevalence of positive AD biomarkers in the AD group, 92.3% (12/13); and a low prevalence in the normal controls, 20%; almost half (48%) of the patients diagnosed with MCI had positive amyloid detection. After a one year, the significant differences found at baseline on neuropsychological testing were similar at the follow-up assessment even though the AD group had significantly altered its functional performance (FAQ and CDR). The exception was semantic fluency, which showed greater impairment between the AD group and MCI and normal controls respectively. For these tests, the addition of AD biomarkers as a variable did not significantly alter the variations previously found for the established clinical group's model. Finally, the one-year conversion rate to dementia was 20% in the MCI cohort.

RESUMO El estudio de Argentina-Alzheimer's Disease Neuroimaging Initiative (Arg-ADNI) es una cohorte prospectiva de 50 pacientes seguidos en una misma institución. Fueron evaluados cognitivamente 15 controles normales (CN), 24 sujetos con deterioro cognitivo leve (DCL) y 12 con demencia tipo Alzheimer (DTA) leve. En los DTA, 92,3% tuvieron biomarcadores positivos para Alzheimer y 20% en los CN. Casi la mitad de los DCL presentaron biomarcadores positivos. Después de un año de seguimiento, la diferencias significativas halladas en la visita de inicio en las pruebas cognitivas fueron similares al año aunque los DTA tuvieron empeoramiento funcional medido en el FAQ y CDR. La excepción fue la fluencia semántica, la cual mostró mayor declinación entre DTA y los demás grupos. La incorporación de los biomarcadores como variable no alteró significativamente los hallazgos de grupo. La tasa de conversión a demencia anual fue del 20%.

Disfunção cognitiva pode ocorrer em 17-40 % dos pacientes com atrofia de múltiplos sistemas (AMS). Alguns estudos têm sugerido a presença de disfunção cognitiva mais leve nos pacientes com AMS do tipo cerebelar (AMS-C) do que na variante parkinsoniana (AMS-P). Objetivo Avaliar os perfis cognitivos de uma série de pacientes argentinos com “Provável AMS”. Método Foram selecionados 6 AMS-P e 3 AMS–C aos quais foi aplicada uma extensa bateria de testes cognitivos. Resultados Depressão foi detectada em 43% dos pacientes. Sete pacientes apresentaram comprometimento de pelo menos um domínio cognitivo. As funções de orientação temporo-espacial, habilidades visuo-espaciais, função executiva e de atenção, memória episódica e linguagem foram comprometidas em pacientes com AMS-P. Nos pacientes com AMS-C as dificuldades cognitivas ficaram restritas às funções executivas e de atenção. Conclusão Apesar do pequeno tamanho da amostra, nossos achados sugerem que pacientes com AMS-P apresentam um comprometimento cognitivo mais amplo do que pacientes com AMS-C.

Cognitive dysfunction may occur in 17-40% of patients with multiple system atrophy (MSA). It has been suggested a milder cognitive impairment in cerebellar (MSA-C) than in parkinsonian variant (MSA-P). However, differences in cognitive profiles remain under discussion. Objective To evaluate cognitive features in a series of patients with “probable MSA” from Argentina. Method After informed consent was obtained, an extensive cognitive tests battery was administered. Nine patients (6 MSA-P and 3 MSA-C) composed the sample. Results Depression was detected in 43% of patients. Seven patients showed at least one cognitive domain impairment. Temporospatial orientation, visuospatial abilities, executive and attentional functions, episodic memory and language were compromised in MSA-P, while MSA-C dysfunction was restricted to attentional and executive domains. Conclusion Despite the small sample size, our findings could suggest a more widespread cognitive impairment in MSA-P than MSA-C.

Los tratamientos de rehabilitación neurológica se fundamentan en una propiedad intrínseca del Sistema Nervioso Central: la de adaptarse a los cambios en su entorno. La Plasticidad Cerebral involucra modificaciones estructurales y funcionales en las neuronas y en las redes neuronales y para su comprensión es necesario contemplar lo que sucede en diferentes niveles, considerando asimismo los factores genéticos y no genéticos que pueden influir en estos procesos. En la actualidad existen técnicas electrofisiológicas y por imágenes que permiten el estudio de la Plasticidad Cerebral en los seres humanos sanos y con lesiones cerebrales. Una mayor comprensión de los fenómenos que ocurren en el Sistema Nervioso luego de una lesión puede posibilitar la aplicación de intervenciones terapéuticas adaptadas a las necesidades de cada individuo.

Neurological rehabilitation treatments are based on an intrinsic property of the Central Nervous System: to adapt to changes in their environment. Cerebral Plasticity involves structural and functional changes in neurons and neural networks and to their understanding is necessary to consider what happens at different levels, considering also genetic and non-genetic factors that may influence these processes. There are currently electrophysiological and images that allow the study of Brain Plasticity in healthy humans and with brain injuries. Greater understanding the phenomena that occur in the nervous system after an injury may enable therapeutic application tailored to the needs of each individual.

Cognitive impairment and dementia treatment costs are significant for health systems. According to national and international guidelines, recommended drugs for treatment of dementias are cholinesterase inhibitors (donepezil, galantamine, rivastigmine) and memantine. Despite these guidelines recommendations, other nootropics, vasodilators and antioxidants are often used in Argentina. The purpose of this study was to describe and compare the prescription pattern of commonly used drugs for the treatment of cognitive disorders and dementia in different regions of Argentina. An observational, retrospective study of 1 814 108 recipes prescribed to National Institute of Social Services for Retired and Pensioners outpatients during the during the second half of 2008 and the first and second half of 2009 was performed, taking in count the whole country and also different Argentina´s regions. Demographic variables, quantity and rate of prescriptions, dosage forms and strengths were analyzed. Considering the entire country, memantine was the most prescribed drug in these periods (570 893 packages). An increase in the memantine, donepezil, rivastigmine and idebenone rates of prescription was observed. Prescription rate of memantine increased in the North-West and North-East regions, that of idebenone in the North-East region and Patagonia and donepezil in the North-East region. Non recommended drugs were highly prescribed in all the analyzed regions. Some of them were indicated to young and middle-aged patients.

Los costos originados por trastornos cognitivos y demencias son significativos para los sistemas de salud. Según guías nacionales e internacionales, los fármacos recomendados para su tratamiento son inhibidores de colinesterasa (donepecilo, galantamina y rivastigmina) y memantina. En la Argentina también son utilizados otros nootrópicos, galantamina, rivastigmina, vasodilatadores, vitaminas y antioxidantes. El objetivo del presente estudio es describir y comparar el patrón de prescripción de drogas para el tratamiento de trastornos cognitivos y demencias en las distintas regiones del país. Se realizó un estudio observacional retrospectivo a partir de las prescripciones (1 814 108 envases) realizadas en la práctica clínica habitual durante el segundo semestre del 2008 y el primer y segundo semestre del 2009. El trabajo fue realizado sobre la población total del Instituto Nacional de Servicios Sociales para Jubilados y Pensionados. Se analizaron variables demográficas, cantidad y tasa de prescripciones, presentaciones y dosis utilizadas por regiones. Considerando todo el país, memantina fue la droga más prescripta en esos períodos, con un total de 570 893 envases. Memantina, donepecilo, rivastigmina e idebenona presentaron un incremento en las tasas de prescripción 2008-2009. Analizando los cambios regionales en tasas de prescripción, la memantina aumentó en el Noroeste y Noreste argentino, la idebenona en el Noroeste y la Patagonia y el donepecilo en el Noreste. Grupos de fármacos no recomendados fueron altamente prescriptos en todas las regiones del país. Algunos fueron indicados en adultos jóvenes o de mediana edad.