Categoría: Papers con abstracts

Topics in dementia: papers from the WFN-RGACD 2010 meeting . Autores Manes F.  Año 2012 Journal  Manes F.  Volumen 25(1): 1-2 Abstract   Otra información    

OBJECT: Executive functions are crucial for organizing and integrating cognitive processes. While some studies have assessed the effect of carotid artery stenting (CAS) on cognitive functioning, results have been conflicting. The object of this study was to assess the effect of CAS on cognitive status, with special interest on executive functions, among patients with severe asymptomatic internal carotid artery (ICA) stenosis. METHODS: The authors prospectively assessed the neuropsychological status of 20 patients with unilateral asymptomatic extracranial ICA stenosis of 60% or more by using a comprehensive assessment battery focused on executive functions before and after CAS. Individual raw scores on neuropsychological tests were converted into z scores by normalizing for age, sex, and years of education. The authors compared baseline and 3-month postoperative neuropsychological scores by using Wilcoxon signed-rank tests. RESULTS: The mean preoperative cognitive performance was within normal ranges on all variables. All patients underwent a successful CAS procedure. Executive function scores improved after CAS, relative to baseline performance as follows: set shifting (Trail-Making Test Part B: -0.75 ± 1.43 vs -1.2 ± 1.48, p = 0.003) and processing speed (digit symbol coding: -0.66 ± 0.85 vs -0.97 ± 0.82, p = 0.035; and symbol search: -0.24 ± 1.32 vs -0.56 ± 0.77, p = 0.049). The benefit of CAS for working memory was marginally significant (digit span backward: -0.41 ± 0.61 vs -0.58 ± 0.76, p = 0.052). Both verbal (immediate Rey Auditory Verbal Learning Test: 0.35 ± 1.04 vs -0.22 ± 0.82, p = 0.011) and visual (delayed Rey-Osterrieth Complex Figure: 0.27 ± 1.26 vs -0.22 ± 1.01, p = 0.024) memory improved after CAS. CONCLUSIONS: The authors found a beneficial effect on executive function and memory 3 months after CAS among their prospective cohort of consecutive patients with unilateral and asymptomatic ICA stenosis of 60% or more.

OBJECTIVE: Most neurocognitive studies have not taken into account the fact that older patients with bipolar disorder (BD) are a heterogeneous population. The main goal of this study was to compare neurocognitive performance and extrapyramidal symptoms in older patients with early-onset BD (EO-BD) and late-onset BD (LO-BD).METHODS: Euthymic older patients with EO-BD (n=20), LO-BD (n=20), and healthy controls (n=20) were evaluated with traditional clinical instruments and measures of exposure to psychotropic drugs, as well as extrapyramidal symptoms. All subjects completed an extensive neuropsychological battery.RESULTS: Patients with EO-BD showed poorer performance than healthy controls in two measures of verbal memory and two measures of executive functions, whereas patients with LO-BD exhibited lower performance scores than healthy controls in almost all of the measures assessed. Impairments in the LO-BD group included even neurocognitive domains typically spared in mixed-age patients. Additionally, there was a trend toward displaying higher extrapyramidal symptoms in the LO-BD group compared with both EO-BD and healthy control groups. In both patient groups, psychosocial functioning was related with executive dysfunction and extrapyramidal symptoms.CONCLUSIONS: Patients with LO-BD may have more extensive and severe cognitive impairments, as well as higher vulnerability to extrapyramidal symptoms, compared with patients with EO-BD. Cognitive-motor disturbances may help to explain impairments in daily functioning among older patients with EO-BD and LO-BD during remission.

Objective: Several longitudinal studies had shown that early deprivation and institutionalization during the first six months of life affects the emotional, cognitive, social and neurophysiologic development. Nevertheless, our understanding of possible similar effects of delayed institutionalization, in preschool-age remains unclear to this day. The goal of this study is to evaluate the cognitive performance of institutionalized children with history of preschool-age physical abandonment. Method: 18 male institutionalized children with history of abandonment during the preschool-age (2-5 years old) and comparison group matched by age, handedness, gender, educational and socioeconomic level were tested on multiple tasks of attention, memory and executive functions. Results: We found a cognitive impairment in the institutionalized children in several measures of attention, memory and executive functions. This is the first report of cognitive impairment related to late abandonment and institutionalization effects (after 2 years old), extending the already known effects on early institutionalization. Conclusions: This preliminary study suggests that environmental factors including abandonment and institutional care, can affect not only the infancy period, but also the preschool period providing new insights into our understanding of neurocognitive development.

Objective: To investigate the presence of dysfunctional cognitions in adults with ADHD and to determine whether these cognitions are associated with emotional symptoms, maladaptive coping, and functional impairment, as predicted by the cognitive-behavioral model. Method: A total of 35 adult participants with ADHD, 20 nonclinical controls, and 20 non-ADHD clinical controls were assessed with measures of ADHD symptoms, dysfunctional cognitions, depression and anxiety symptoms, coping strategies, and quality of life. Results: ADHD group showed elevated scores of dysfunctional cognitions relative to nonclinical control group and comparable with clinical control group. Dysfunctional cognitions were strongly associated with emotional symptoms. ADHD group also showed elevated scores in maladaptive coping strategies of the escape-avoidance type. Life impairment was satisfactorily predicted in data analysis when ADHD symptoms, dysfunctional cognitions, and emotional symptoms were fitted into a regression model. Conclusion: Cognitive-behavioral therapy model appears to be a valid complementary model for understanding emotional and life impairment in adults with ADHD.

Only a small proportion of individuals with Mild Cognitive Impairment (MCI) will convert to dementia. Methods currently available to identify risk for conversion do not combine enough sensitivity and specificity, which is even more problematic in low-educated populations. Current guidelines suggest the use of combined markers for dementia to enhance the prediction accuracy of assessment methods. The present study adhered to this proposal and investigated the sensitivity and specificity of the electrophysiological component P300 and standard neuropsychological tests to assess patients with Alzheimer´s disease (AD) and MCI recruited from a low-income country. The neuropsychological battery comprised tests of memory, attention, language, praxis and executive functions. The P300 was recorded using a classical visual odd-ball paradigm. Three variables were found to achieve sensitivity and specificity values above 80% (Immediate and Delayed recall of word list – CERAD – and the latency of P300) for both MCI and AD. When they entered the model together (i.e., combined approach) the sensitivity for MCI increased to 96% and the specificity remained high (80%). Our preliminary findings suggest that the combined use of sensitive neuropsychological tasks and the analysis of the P300 may offer a very useful method for the preclinical assessment of AD, particularly in populations with low socioeconomic and educational levels. Our results provide a platform and justification to employ more resources to convert P300 and related parameters into a biological marker for AD.

In this work, we explored convergent evidence supporting the fronto-striatal model of obsessive-compulsive disorder (FSMOCD) and the contribution of event-related potential (ERP) studies to this model. First, we considered minor modifications to the FSMOCD model based on neuroimaging and neuropsychological data. We noted the brain areas most affected in this disorder -anterior cingulate cortex (ACC), basal ganglia (BG) and orbito-frontal cortex (OFC)- and their related cognitive functions, such as monitoring and inhibition. Then, we assessed the ERPs that are directly related to the FSMOCD, including the error-related negativity (ERN), N200 and P600. Several OCD studies present enhanced ERN and N2 responses during conflict tasks as well as an enhanced P600 during working memory tasks. Evidence from ERP studies (especially regarding ERN and N200 amplitude enhancement), neuroimaging and neuropsychological findings suggests abnormal activity in the OFC, ACC and BG in OCD patients. Moreover, additional findings from these analyses suggest dorsolateral prefrontal and parietal cortex involvement, which might be related to executive function deficits. Thus, these convergent results suggest the existence of a self-monitoring imbalance involving inhibitory deficits and executive dysfunctions. OCD patients present an impaired ability to monitor, control, and inhibit intrusive thoughts, urges, feelings and behaviors. In the current model, this imbalance is triggered by an excitatory role of the BG (associated with cognitive or motor actions without volitional control) and inhibitory activity of the OFC as well as excessive monitoring of the ACC to block excitatory impulses. This imbalance would interact with the reduced activation of the parietal-DLPC network, leading to executive dysfunction. ERP research may provide further insight regarding the temporal dynamics of action monitoring and executive functioning in OCD.

INTRODUCCIÓN: La simulación de enfermedad mental ha sido un recurso utilizado por losimputados en causas penales con el fin de obtener beneficios ligados a la exención de la pena porun delito cometido, elección del lugar de alojamiento, trato o tratamiento recibido durante lareclusión. OBJETIVO: El presente trabajo intenta desarrollar un instrumento objetivo deevaluación que permita discriminar a los simuladores de enfermedad mental de los pacientespsiquiátricos dentro del ámbito penal. PACIENTES Y MÉTODO: Se evaluaron 92 derivaciones ala Unidad Psiquiátrica de Varones U.20 del Servicio Penitenciario Federal. Las evaluaciones serealizaron en la Sala de Observación y Evaluación Psiquiátrica (SOEP) por psiquiatras,neuropsicológos y trabajadores sociales. Se utilizaron criterios estandarizados de detección deSimulación, pruebas de diagnóstico clínico (MINI) y el Protocolo de Evaluación de Simulación(PES). RESULTADOS: El PES presentó, utilizando como punto de corte 17,5 puntos, un gradode sensibilidad de 92% y de especificidad de 95%. Los resultados obtenidos no han sidoinfluenciados por el nivel educativo, diagnóstico o causa penal del evaluado, tampoco por la edad o los antecedentes tóxicos del mismo. El protocolo no ha discriminado el resultado desimuladores vs. retrasos mentales moderados/grave. CONCLUSIONES: El PES resulta unaherramienta útil para el diagnóstico clínico de simulación dentro del ámbito penal. La correctadiferenciación de patologías psiquiátricas u otros problemas que requieran de atención(problemas institucionales, familiares, legales) resulta en un beneficio para el pacientepsiquiátrico prisionizado y el cuidado del espacio de tratamiento para los mismos.

We assessed cognitive performance and physical disability in 111 multiple sclerosis (MS) patients and 222 healthy controls in a multicenter study in Argentina to obtain the prevalence of cognitive impairment (CI) in a population of MS outpatients in Argentina. MS patients presented significantly lower scores in all Brief Repeatable Battery of Neuropsychology (BRB-N) tests than did the control group. The prevalence of CI was 43.2%. This study allowed us to obtain actual figures on the number of MS patients with CI in a Latin American sample. This validation is a very useful tool for clinical practice and for research studies to assess cognition in MS.

Introduction: The development of screening tools for the assessment of cognitive status in patients with dementia must be brief yet both highly sensitive and specific in order to ensure its clinical utility. In this sense, it is important to adapt tools widely used around the world to particular populations, allowing for a more proper validity of its use in everyday clinical practice. One of the most popular general cognitive screening tools is the Addenbrooke´s Cognitive Examination (ACE), which has been adapted and validated in multiple languages and populations. Objective: To assess the usefulness of the Peruvian version of the ACE in patients with dementia. Materials and methods: Healthy controls, patients with Alzheimer disease (AD) and patients with Frontotemporal Dementia (FTD) were assessed with the Peruvian version of the ACE, the ADAScog to determine dementia severity, and a complete neuropsychological battery. Results: The Peruvian version of the ACE showed very good internal con- sistency, strong concurrent validity as revealed by significant correlations between the ACE total score and both the MMSE and ADAScog. The ACE was able to differentiate healthy controls from patients with dementia with high discriminatory accuracy. Using a cut-off score of 86 (out of 100), the ACE was exhibited a sensitivity of 100% and a specificity of 100%.