Resumen Los grandes avances en las neurociencias en las últimas 3 décadas han hecho hincapié en la comprensión de las perturbaciones en el pensamiento, el comportamiento y las emociones. Mientras que la psiquiatría y la neurología se ocupan de enfermedades del cerebro, recientemente ha habido una creciente necesidad de tener un enfoque neuropsiquiátrico combinado para tratar muchos trastornos. Además, hay múltiples condiciones en las que confluyen habilidades y bases de conocimiento de ambas disciplinas. Este es el territorio cubierto por la subespecialidad de Neuropsiquiatría desde una perspectiva de salud «mental» y la Neurología Conductual desde una perspectiva de salud «cerebral». Este artículo elabora el enfoque neuropsiquiátrico para tratar las enfermedades cerebrales, pero también discute los límites del territorio neuropsiquiátrico. En este proceso, se describe un currículo para la formación de un neuropsiquiatra o un neurólogo conductual competente para proveer un abordaje integral en términos diagnósticos y terapéuticos. El documento describe con cierto detalle los objetivos de la formación en neuropsiquiatría y las competencias clave que se debe alcanzar en dicha formación superior, después de una formación inicial en psiquiatría y neurología. Al mismo tiempo que aspira a un programa de formación internacionalmente pertinente, el documento reconoce las diferencias locales y regionales en materia de conocimientos y requisitos de formación. Proporciona un marco común de formación tanto para la Neuropsiquiatría como para la Neurología Conductual, aceptando las diferencias en habilidades y el énfasis que la formación básica en psiquiatría o neurología traerá a la formación de la subespecialidad. El futuro de la Neuropsiquiatría (o Neurología Conductual) como disciplina estará influido por la instauración exitosa de un currículo de capacitación unificado.

Abstract With major advances in neuroscience in the last three decades, there is an emphasis on understanding disturbances in thought, behaviour and emotion in terms of their neuroscientific underpinnings. While psychiatry and neurology, both of which deal with brain diseases, have a historical standing as distinct disciplines, there has been an increasing need to have a combined neuropsychiatric approach to deal with many conditions and disorders. Additionally, there is a body of disorders and conditions that warrants the skills sets and knowledge bases of both disciplines. This is the territory covered by the subspecialty of Neuropsychiatry from a 'mental' health perspective and Behavioural Neurology from a 'brain' health perspective. This paper elaborates the neuropsychiatric approach to dealing with brain diseases, but also argues for the delineation of a neuropsychiatric territory. In the process, it describes a curriculum for the training of a neuropsychiatrist or a behavioural neurologist who is competent in providing a unified approach to the diagnosis and management of this set of conditions and disorders. The paper describes in some detail the objectives of training in neuropsychiatry and the key competencies that should be achieved in such higher training after a foundational training in psychiatry and neurology. While aiming for an internationally relevant training program, the paper acknowledges the local and regional differences in training expertise and requirements. It provides a common framework of training for both Neuropsychiatry and Behavioural Neurology, while accepting the differences in skills and emphasis that basic training in psychiatry or neurology will bring to the subspecialty training. The future of Neuropsychiatry (or Behavioural Neurology) as a discipline will be influenced by the successful adoption of such a unified training curriculum.

Resumen La neuropsiquiatría es una disciplina médica cuyo campo clínico, académico y científico se localiza en el territorio fronterizo entre la neurología y la psiquiatría. En este artículo se aborda la definición teórica de la neuropsiquiatría y, con el objetivo de tratar los aspectos prácticos de la neuropsiquiatría, se describe el perfil de un servicio de interconsulta neuropsiquiátrica en el contexto de un hospital dedicado a las enfermedades del sistema nervioso, en un país de ingreso económico medio. Se incluyó a 1.212 pacientes evaluados consecutivamente en el Instituto Nacional de Neurología y Neurocirugía de México. Los diagnósticos principales fueron infecciones cerebrales (21%), neoplasias del sistema nervioso (17%), enfermedad cerebrovascular (14%), epilepsia (8%), enfermedades de la sustancia blanca (5%), neuropatías periféricas (5%), enfermedades extrapiramidales (4%), ataxias (2%) y traumatismos craneoencefálicos (1,8%). Los diagnósticos neuropsiquiátricos más frecuentes fueron síndrome confusional (36%), depresión (16,4%), demencia (14%), ansiedad (8%), síndromes frontales (5%), reacciones de ajuste (4%), psicosis (3%), trastornos somatoformes (3%) y catatonia (3%). El territorio fronterizo entre la neurología y la psiquiatría es extenso y requiere los conocimientos y fortalezas de ambas disciplinas, pero también la pericia entrenada mediante un programa clínico, científico y académico especializado.

Abstract Neuropsychiatry is a specialized clinical, academic and scientific discipline with its field located in the borderland territory between neurology and psychiatry. In this article, we approach the theoretical definition of neuropsychiatry, and in order to address the practical aspects of the discipline, we describe the profile of a neuropsychiatric liaison service in the setting of a large hospital for neurological diseases in a middle-income country. An audit of consecutive in-patients requiring neuropsychiatric assessment at the National Institute of Neurology and Neurosurgery of Mexico is reported, comprising a total of 1212 patients. The main neurological diagnoses were brain infections (21%), brain neoplasms (17%), cerebrovascular disease (14%), epilepsy (8%), white matter diseases (5%), peripheral neuropathies (5%), extrapyramidal diseases (4%), ataxia (2%), and traumatic brain injury and related phenomena (1.8%). The most frequent neuropsychiatric diagnoses were delirium (36%), depressive disorders (16.4%), dementia (14%), anxiety disorders (8%), frontal syndromes (5%), adjustment disorders (4%), psychosis (3%), somatoform disorders (3%), and catatonia (3%). The borderland between neurology and psychiatry is a large territory that requires the knowledge and clinical skills of both disciplines, but also the unique expertise acquired in a clinical and academic neuropsychiatry program.

O autor apresenta uma visão geral da literatura atual sobre homocisteína como um fator de risco para os transtornos neuropsiquiátricos. Foram pesquisados os bancos de dados MEDLINE, Current Contents e EMBASE (entre 1966 e 2002) para publicações em língua inglesa utilizando as palavras-chave ''Homocisteína'' e ''AVC''; ''Doença de Alzheimer''; ''Déficit Cognitivo'', ''Epilepsia'', ''Depressão'' ou ''Doença de Parkinson''. Artigos individuais foram pesquisados para referências cruzadas relevantes. É biologicamente plausível que altos níveis de homocisteína possam causar lesão cerebral e transtornos neuropsiquiátricos. A homocisteína é pró-aterogênica e pró-trombótica. Dessa forma, aumenta o risco de acidente vascular cerebral, podendo ter um efeito neurotóxico direto. Evidências de que a homocisteína seja um fator de risco para doença microvascular cerebral são conflitantes, mas justificam maiores estudos. Estudos transversais e alguns longitudinais suportam a crescente prevalência de acidente vascular cerebral e demência vascular em indivíduos com hiper-homocisteinemia. As evidências de crescente neurodegeneração estão se acumulando. A relação com a depressão ainda é experimental, da mesma forma como com a epilepsia. Atualmente, estudos sobre tratamentos são necessários para colocar as evidências sobre bases mais sólidas. Os pacientes de alto risco também devem ser pesquisados para hiper-homocisteínemia, cujo tratamento deve ser feito com ácido fólico. Mais evidências são necessárias antes que pesquisas populacionais possam ser recomendadas.

The author presents an overview of the current literature on homocysteine as a risk factor for neuropsychiatric disorders. The databases MEDLINE, Current Contents and EMBASE were searched (between 1966 and 2002) for English language publications with the key words 'Homocysteine' and 'Stroke'; 'Alzheimer Disease'; 'Cognitive Impairment'; 'Epilepsy'; 'Depression'; or 'Parkinson's disease'. Individual articles were hand searched for relevant cross-references. It is biologically plausible that high homocysteine levels may cause brain injury and neuropsychiatric disorders. Homocysteine is proatherogenic and prothrombotic, thereby increasing the risk of cerebrovascular disease, and may have a direct neurotoxic effect. Evidence for homocysteine as a risk factor for cerebral microvascular disease is conflicting but warrants further study. Cross-sectional and some longitudinal studies support increased prevalence of stroke and vascular dementia in hyperhomocysteinemic individuals. The evidence of increased neurodegeneration is accumulating. The relationship with depression is still tentative, as it is with epilepsy. Currently, treatment studies are necessary to place the evidence on a stronger footing, and maybe high-risk patients should be screened for hyperhomocysteinemia and this should be treated with folic acid. More research evidence is necessary before population screening can be recommended.