Easton JD, Lopes R, Dra. Cecilia Bahit, Wojdyla D, Wranger C, Wallentin L, Alings M, Goto S, Lewis B, Rosenqvist M, Hanna M, Mohan P, Alexander J, Diener HC.  Apixaban compared with warfarin in patients with atrial fibrillation and previous stroke or transient ischaemic attack: a subgroup analysis of the ARISTOTLE trial. Lancet Neurology 2012

In the ARISTOTLE trial, the rate of stroke or systemic embolism was reduced by apixaban compared with warfarin in patients with atrial fibrillation (AF). Patients with AF and previous stroke or transient ischaemic attack (TIA) have a high risk of stroke. We therefore aimed to assess the efficacy and safety of apixaban compared with warfarin in prespecified subgroups of patients with and without previous stroke or TIA. METHODS: Between Dec 19, 2006, and April 2, 2010, patients were enrolled in the ARISTOTLE trial at 1034 clinical sites in 39 countries. 18,201 patients with AF or atrial flutter were randomly assigned to receive apixaban 5 mg twice daily or warfarin (target international normalised ratio 2·0-3·0). The median duration of follow-up was 1·8 years (IQR 1·4-2·3). The primary efficacy outcome was stroke or systemic embolism, analysed by intention to treat. The primary safety outcome was major bleeding in the on-treatment population. All participants, investigators, and sponsors were masked to treatment assignments. In this subgroup analysis, we estimated event rates and used Cox models to compare outcomes in patients with and without previous stroke or TIA. The ARISTOTLE trial is registered with ClinicalTrials.gov, number NTC00412984. FINDINGS: Of the trial population, 3436 (19%) had a previous stroke or TIA. In the subgroup of patients with previous stroke or TIA, the rate of stroke or systemic embolism was 2·46 per 100 patient-years of follow-up in the apixaban group and 3·24 in the warfarin group (hazard ratio [HR] 0·76, 95% CI 0·56 to 1·03); in the subgroup of patients without previous stroke or TIA, the rate of stroke or systemic embolism was 1·01 per 100 patient-years of follow-up with apixaban and 1·23 with warfarin (HR 0·82, 95% CI 0·65 to 1·03; p for interaction=0·71). The absolute reduction in the rate of stroke and systemic embolism with apixaban versus warfarin was 0·77 per 100 patient-years of follow-up (95% CI -0·08 to 1·63) in patients with and 0·22 (-0·03 to 0·47) in those without previous stroke or TIA. The difference in major bleeding with apixaban compared with warfarin was 1·07 per 100 patient-years (95% CI 0·09-2·04) in patients with and 0·93 (0·54-1·32) in those without previous stroke or TIA. INTERPRETATION: The effects of apixaban versus warfarin were consistent in patients with AF with and without previous stroke or TIA. Owing to the higher risk of these outcomes in patients with previous stroke or TIA, the absolute benefits of apixaban might be greater in this population. FUNDING: Bristol-Myers Squibb and Pfizer.

Melloni M, Urbistondo C, Sedeño L, Gelormini C, Kichic R, Ibanez A.  The Extended Fronto-Striatal Model of Obsessive Compulsive Disorder: Convergence from Event-Related Potentials, Neuropsychology and Neuroimaging. Frontiers in Human Neuroscience 2012

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.

Bertone MS, Ortiz Lugo ME, Vallejos M, Márquez E, Muniello J, López PL, Corominas A.  Detección de la Simulación de Enfermedad Mental dentro del ámbito penitenciario mediante el Protocolo de Evaluación de Simulación (PES). Psiquiatria.com 2012

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.

Custodio N, Lira D, Montesnos R, Gleichgerrcht E, Manes F.  Usefulness of the Addenbrookes’s Cognitive Examination (Spanish version) in Peruvian patients with Alzheimer’s Disease and Frontotemporal Dementia. Vertex 2012 10.1016/j.cognition.2014.02.001

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%.

Couto JB, Sedeño L, Sposato L, Sigman M, Riccio PM, Salles A, Lopez V, Johannes Schroeder, Manes F, Ibanez A.  Insular networks for emotional processing and social cognition: comparison of two case reports with either cortical or subcortical involvement. Cortex 2012

INTRODUCTION: The processing of the emotion of disgust is attributed to the insular cortex (IC), which is also responsible for social emotions and higher-cognitive functions. We distinguish the role of the IC from its connections in regard to these functions through the assessment of emotions and social cognition in a double case report. These subjects were very rare cases that included a focal IC lesion and a subcortical focal stroke affecting the connections of the IC with frontotemporal areas. MATERIALS & METHODS: Both patients and a sample of 10 matched controls underwent neuropsychological and affective screening questionnaires, a battery of multimodal basic emotion recognition tests, an emotional inference disambiguation task using social contextual clues, an empathy task and a theory of mind task. RESULTS: The insular lesion (IL) patient showed no impairments in emotion recognition and social emotions and presented with a pattern of delayed reaction times (RTs) in a subset of both groups of tasks. The subcortical lesion (SL) patient was impaired in multimodal aversive emotion recognition, including disgust, and exhibited delayed RTs and a heterogeneous pattern of impairments in subtasks of empathy and in the contextual inference of emotions. CONCLUSIONS: Our results suggest that IC related networks, and not the IC itself, are related to negative emotional processing and social emotions. We discuss these results with respect to theoretical approaches of insular involvement in emotional and social processing and propose that IC connectivity with frontotemporal and subcortical regions might be relevant for contextual emotional processing and social cognition.

López PL, Cetkovich M, Lischinsky A, Alvarez Prado D, Torrente F.  Propiedades psicométricas de la Escala de Impulsividad de Barratt en una muestra de Buenos Aires. Vertex 2012

La escala de impulsividad de Barratt es un instrumento diseñado para evaluar el constructo impulsividad en tres dimensiones: atencional, motora y no planeada. La escala ha sido aplicada en pacientes con diferentes diagnósticos, en los cuales la sintomatología de impulsividad es característica. En Argentina no existen estudios que evalúen las propiedades psicométricas del instrumento en población clínica. El objetivo del trabajo fue evaluar las propiedades psicométricas de la escala en una muestra de la Ciudad de Buenos Aires. Se seleccionaron 150 sujetos adultos: 67 no presentaban diagnóstico psiquiátrico relevante, 56 cumplían criterios de trastorno bipolar y 27 presentaban diagnóstico de trastorno por déficit de atención. Se evaluaron la consistencia interna, la validez de constructo, la validez discriminativa y la estructura factorial. El alfa de Cronbach fue de 0,84 para la escala total. Asimismo, el instrumento ha demostrado indicadores aceptables de validez de constructo y validez discriminativa. Se encontraron diferencias al comparar la estructura factorial original con los resultados del presente estudio. Los resultados apoyan la utilidad de la escala en el contexto psiquiátrico, científico y clínico para evaluar el constructo de impulsividad. El puntaje total de la escala ha obtenido los indicadores más robustos de confiabilidad y validez.

Couto JB, Sedeño L, Ibanez A.  Interocepción y corteza insular: convergencia multimodal y surgimiento de la conciencia corporal. Revista Chilena de Neuropsicología 2012

La interocepción como censado del estado homeostático y visceral, ha sido recientemente postulada como requisito para la conciencia de estados emocionales corporales (Craig, 2009). Vías parasimpáticas y espinotalámicas que codifican esta información corporal tienen relevo en la corteza insular. Simultáneamente, han sido descriptas otras funciones insulares implicadas en procesos conscientes, como la intencionalidad, la toma de decisiones, la conciencia sensorio-motora, la percepción temporal, reconocer la imagen visual de uno mismo o percibir confiables a otros individuos (Craig, 2009; Ibanez, Gleichgerrcht, & Manes, 2010). Esta evidencia, sumada a resultados de estudios de lesión y neuroimágenes funcionales, sugiere que la corteza insular anterior (IA) sería la encargada de integrar señales multimodales cognitivas, emocionales y sociales para dirigir las conductas motivacionales que entrañan la supervivencia del individuo. En esta revisión analizamos el cúmulo de evidencia que involucran a la interocepción y al procesamiento insular integrativo en el surgimiento de estados emocionales conscientes, a través de estudios de lesiones y de técnicas de conectividad funcional en resonancia magnética funcional (RMF).

Ibanez A, Riveros R, Aravena P, Vergara V, Cardona JF, Garcia L, Hurtado E, Martin-Reyes M, Barutta J, Manes F.  When context is hard to integrate: cortical measures of congruency in schizophrenics and healthy relatives from multiplex families. Schizophrenia research 2011 10.3389/fnhum.2013.00467

When context is hard to integrate: cortical measures of congruency in schizophrenics and healthy relatives from multiplex families. Autores Ibanez A, Riveros R, Aravena P, Vergara V, Cardona JF, Garcia L, Hurtado E, Martin-Reyes M, Barutta J, Manes F.  Año 2011 Journal  Ibanez A, Riveros R, Aravena P, Vergara V, Cardona JF, Garcia L, Hurtado E, Martin-Reyes M, Barutta J, Manes F.  Volumen 126(1-3): 303-305 Abstract   Otra información