Cannabinoid receptor gene polymorphisms and cognitive performance in patients with schizophrenia and controls

Objective: To test the hypothesis that genetic variations of cannabinoid receptors contribute to the pathophysiology of cognitive deficits in schizophrenia. Methods: In this genetic association case-control study, cannabinoid receptor polymorphisms CNR1 rs12720071 and CNR2 rs2229579 were tested for association with neurocognitive performance in 69 patients with schizophrenia and 45 healthy controls. Neurocognition was assessed by the Brief Assessment of Cognition in Schizophrenia (BACS). Results: We found a consistent association between CNR1 rs12720071 polymorphism and the cognitive performance of patients in several cognitive domains. Patients with C/C polymorphism presented significantly worse performance in motor speed, verbal fluency, attention/processing speed and reasoning/problem solving. Conclusion: Although limited, our data support the hypothesis that CNR1 variations may be associated with the pathogenesis of cognitive deficits of schizophrenia.

Interview-based assessment of cognition is a strong predictor of quality of life in patients with schizophrenia and severe negative symptoms

Objective: To analyze the correlation between quality of life, symptoms, and cognition assessed by the interview-based Schizophrenia Cognition Rating Scale (SCoRS). Methods: Seventy-nine outpatients diagnosed with schizophrenia were evaluated with the Quality of Life Scale – Brazilian version (QLS-BR), the SCoRS, and symptoms scales (Positive and Negative Syndrome Scale [PANSS]). After determining the potential explanatory variables using Spearman’s correlation and Student’s t test results, we ran simple, multivariate, and decision-tree regression analyses to assess the impact of SCoRS and PANSS ratings on mean overall quality of life. Results: Cognitive deficits and negative symptoms were the best predictors of quality of life. A low degree of negative symptoms (PANSS negative < 11) was a strong predictor of better quality of life (QLS ∼ 75), regardless of SCoRS rating. Among participants with more severe negative symptoms, elevated cognitive impairment (interviewer SCoRS ∼ 44) was a predictor of worse quality of life (QLS ∼ 44). Conclusions: Cognitive impairment determined by interview-based assessment seems to be a strong predictor of quality of life in subjects with severe negative symptoms. These results support the usefulness of SCoRS for cognitive assessment that is relevant to the everyday life of patients with schizophrenia.

Functional capacity: a new framework for the assessment of everyday functioning in schizophrenia

Historically, measures of everyday functioning have focused exclusively on real-world performance. Despite the unquestionable value of “real-world functioning”, it has become clear that instruments for its assessment might not be as accurate as desirable. Functional capacity is a domain of everyday functioning that can be assessed through performance-based measures. In the last decade, functional capacity has become a cornerstone for the assessment of everyday functioning, since, alongside measures of real-world functioning, it provides a much more comprehensive picture of functional outcomes than any measurement alone. Functional capacity is more stable and less vulnerable to influence from environmental factors than other domains, and its correlation with cognitive functions has encouraged the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) project to suggest that a performance-based measure of functional capacity be included as a co-primary assessment of cognition in clinical trials. Functional capacity assessment instruments may be also useful in the evaluation of remission in schizophrenia. Validation of these instruments in different countries is desirable, and should always include cross-cultural adaptation; within large countries, adjustment for regional variations should be considered.

The endocannabinoid system and its role in schizophrenia: a systematic review of the literature / O sistema endocanabinoide e seu papel na esquizofrenia: uma revisão sistemática da literatura

OBJECTIVE: Schizophrenia is a psychiatric disorder whose mechanisms have remained only partially elucidated. The current proposals regarding its biological basis, such as the dopaminergic hypothesis, do not fully explain the diversity of its symptoms, indicating that other processes may be involved. This paper aims to review evidence supporting the involvement of the endocannabinoid system (ECS), a neurotransmitter group that is the target of Cannabis sativa compounds, in this disorder. METHODS: A systematic review of original papers, published in English, indexed in PubMed up to April, 2012. RESULTS: Most studies employed genetics and histological, neuroimaging or neurochemical methods - either in vivo or post-mortem - to investigate whether components of the ECS are compromised in patients. Overall, the data show changes in cannabinoid receptors in certain brain regions as well as altered levels in endocannabinoid levels in cerebrospinal fluid and/or blood. CONCLUSIONS: Although a dysfunction of the ECS has been described, results are not entirely consistent across studies. Further data are warrant to better define a role of this system in schizophrenia.

OBJETIVO: A esquizofrenia é um transtorno psiquiátrico cujos mecanismos permanecem apenas parcialmente elucidados. As atuais propostas relativas à base biológica, tais como a hipótese dopaminérgica, não explicam por completo a diversidade de seus sintomas, o que indica que outros processos podem estar envolvidos. Este artigo tem como objetivo revisar indícios que sustentem o envolvimento do sistema endocanabinoide (SECB), um grupo de neurotransmissoresalvo dos compostos da Cannabis sativa, nesse transtorno. MÉTODOS: Revisão sistemática dos artigos originais, publicados em inglês e indexados no PubMed até abril de 2012. RESULTADOS: A maioria dos estudos empregou métodos neuroquímicos ou de neuroimagem genéticos e histológicos - tanto in vivo quanto post-mortem - para investigar se os componentes do SECB estão comprometidos nos pacientes. De modo geral, os dados mostram mudanças nos receptores canabinoides em determinadas regiões cerebrais, bem como a alteração dos níveis de endocanabinoides no líquido cefalorraquidiano e/ou no sangue. CONCLUSÕES: Ainda que a disfunção do SECB tenha sido descrita, os resultados dos estudos não são totalmente consistentes. São necessários mais dados para definir melhor o papel desse sistema na esquizofrenia.

Epilepsia refratária: a experiência do Núcleo Avançado de Tratamento das Epilepsias do Hospital Felício Rocho (NATE) no período de março de 2003 a dezembro de 2006 / Refractory epilepsy: the experience of the NATE

INTRODUÇÃO: A epilepsia é um problema de saúde pública. Afeta mais de cinqüenta milhões de pessoas em todo mundo e mais de vinte milhões deles continuam apresentando crises que não controlam satisfatoriamente com o uso de medicamentos. As epilepsias refratárias correspondem a cerca de 20 por cento dos pacientes epilépticos e boa parte desses apresentam crises parciais complexas passíveis de tratamento cirúrgico. A indicação cirúrgica criteriosa tem se mostrado eficiente para o controle das crises. OBJETIVO: Apresentar dados epidemiológicos e cirúrgicos dos pacientes submetidos ao tratamento cirúrgico no NATE. METODOLOGIA: Estudo retrospectivo com análise de prontuários e classificação do controle de crises de 46 pacientes considerando a Escala de Engel. RESULTADOS: Predomina o sexo masculino, solteiros, sem história familiar para epilepsia. Pacientes procedentes do Estado de Minas Gerais e outros estados da união. Início das crises na infância para 58,8 por cento dos pacientes sendo o tipo de crise mais freqüente a crise parcial complexa. O déficit de memória foi a queixa cognitiva mais comum. CONCLUSÃO: O controle de crise foi compatível com Engel Ia (sem crise) para 67 por cento dos pacientes. O tratamento cirúrgico revelou-se eficiente para o controle das crises dos pacientes portadores de epilepsia refratária ao tratamento medicamentoso.

INTRODUCTION: Epilepsy is a health public problem. Afflicts more than 50 million people worldwide, and more than 20 million of those affected do not have satisfactory seizures control with medicine. The refractory epilepsy represents 20 percent of all epileptic patients and most of them present partial seizures which can be treated by surgical treatment. The careful surgical recommendation can be efficient to seizure control. PURPOSE: The aim of this study was to present epidemiological and surgical data about patients submitted to surgical treatment in NATE - Advanced Center of Epilepsy Treatment. METHOD: We used a retrospective assessment method and control seizure classification from Engel Scale for 46 epileptic patients submitted to surgical treatment. RESULTS: Our results showed predominant male patients, single, without family history for epilepsy. The patients were from cities of Minas Gerais State and from another States in Brazil. The first seizure occurred in the childhood for 58,8 percent of patients and the more frequent seizure type was complex partial seizure. The predominant cognitive complaint was about memory. CONCLUSION: The surgical treatment for seizure control was good for 67 percent of patients that display Engel Ia classification (without seizures) and has a high likelihood for success in medically intractable temporal lobe epilepsy.