[Frequency of single nucleotide polymorphisms and alpha-synuclein haplotypes associated with sporadic Parkinson's disease in the Mexican population]. / Frecuencia de polimorfismos de nucleotido unico y haplotipos de alfa-sinucleina asociados con la enfermedad de Parkinson esporadica en poblacion mexicana.

INTRODUCTION: Parkinson's disease (PD) is a common neurodegenerative disease which begins in adulthood. Its incidence in Mexico is estimated to be 40-50 cases per 100,000 inhabitants/year and is the fourth reason for medical care in the National Institute of Neurology and Neurosurgery. The protein alpha-synuclein, SNCA, plays a key role in the pathology of PD, and its polymorphisms have been associated with an increased risk of developing the disease. AIM: To evaluate the risk of PD represented by the polymorphisms rs2619364, rs2619363, rs2736990, rs7684318, rs17016074, rs356219, rs356220 and rs356203 of SNCA in a sample of Mexican subjects. SUBJECTS AND METHODS: Altogether 171 patients diagnosed with PD and 171 gender- and age-paired controls were assessed by means of real-time polymerase chain reaction, and a statistical analysis was performed to determine the association between the polymorphisms and the disease. RESULTS: The SNCA variants rs356220, rs356203, rs7684318 and rs2736990 were associated with the disease and form two haplotypes with a high risk of developing sporadic PD in the Mexican population. CONCLUSIONS: Variations in SNCA are a risk factor for the development of PD and can act as specific genetic biomarkers as a diagnostic support tool in sporadic PD for Mexican mestizo patients.

TITLE: Frecuencia de polimorfismos de nucleotido unico y haplotipos de alfa-sinucleina asociados con la enfermedad de Parkinson esporadica en poblacion mexicana.Introduccion. La enfermedad de Parkinson (EP) es una entidad neurodegenerativa comun de inicio en la etapa adulta. Su incidencia en Mexico se estima en 40-50 casos por 100.000 habitantes/año y constituye la cuarta causa de atencion medica en el Instituto Nacional de Neurologia y Neurocirugia. La proteina alfa-sinucleina, SNCA, es clave en la patologia de la EP y sus polimorfismos se han asociado a un riesgo aumentado de desarrollarla. Objetivo. Evaluar el riesgo que representan los polimorfismos rs2619364, rs2619363, rs2736990, rs7684318, rs17016074, rs356219, rs356220 y rs356203 de SNCA en una muestra de sujetos mexicanos para la EP. Sujetos y metodos. Se evaluaron 171 pacientes con diagnostico de EP y 171 controles pareados por sexo y edad mediante reaccion en cadena de la polimerasa en tiempo real, y se realizo un analisis estadistico para determinar la asociacion de los polimorfismos con la enfermedad. Resultados. Las variantes rs356220, rs356203, rs7684318 y rs2736990 de SNCA estan asociadas a la enfermedad y forman dos haplotipos de riesgo elevado para desarrollar EP esporadica en la poblacion mexicana. Conclusiones. Las variaciones en SNCA son un factor de riesgo para desarrollar EP y pueden ser biomarcadores geneticos especificos para pacientes mestizos mexicanos como herramienta de apoyo diagnostico en la EP esporadica.

Taking or not taking medications: psychiatric treatment perceptions in patients diagnosed with bipolar disorder.

WHAT IS KNOWN AND OBJECTIVE: Bipolar disorder is a common and disabling condition. Although its negative impact may be limited in some way by the use of different treatment options, lack of adherence to psychiatric treatment is still an obstacle to overcome. Because there are many factors involved in non-adherence to treatment, in this study, we sought to examine the subjective aspect of this phenomenon. We analysed perceptions of both the disease and the treatment in a group of patients with bipolar disorder. METHODS: We incorporated a qualitative design that included 50 outpatients diagnosed with bipolar disorder type 1. Through semi-structured interviews, we explored patients' perceptions of bipolarity and psychiatric medication management. RESULTS AND DISCUSSION: The participants reported the use of medications as one of the most troubling aspects of having bipolar disorder. The fear of becoming addicted to psychiatric drugs was repeatedly mentioned among the patients as an argument for abandoning treatment. The main expectation of treatment was to achieve stable mood, but the patients considered that drugs were not the only way to be euthymic. WHAT IS NEW AND CONCLUSIONS: The patients expressed ambivalence between the need to take medication to remain stable and the fear of negative consequences of using psychiatric drugs. Personal beliefs and environmental influences seem to determine each individual's final choice of whether to maintain or discontinue treatment; so, in everyday clinical practice, it would be necessary to discuss perceptions of the disease with patients and their families.

The beneficial effects of combining pharmacological and psychosocial treatment on remission and functional outcome in outpatients with schizophrenia.

OBJECTIVE: The effects of pharmacological and psychosocial treatment on remission and the functional outcome in outpatients with schizophrenia were evaluated. Remission was assessed according to the criteria proposed by the Remission in Schizophrenia Working group and psychosocial functioning according to the Global Assessment of Functioning with a score > 60. Functional outcome was the result of these two variables. METHOD: One hundred fifty two patients were randomized to receive either, antipsychotic treatment as usual (TAU) or social skills training and family psychoeducation in addition to TAU. A final sample of 119 patients: n = 68 in the social skills training group, and n = 51 in the TAU group completed the study protocol. Patients were assessed at baseline and at 6-month follow-up. RESULTS: At the end of the study, 80% of the patients fulfilled the criteria for symptomatic remission: 62 patients (91.2%) in the social skills training group in contrast to 34 patients (66.7%) in the TAU group. Functional improvement criteria were accomplished by 41 patients (34.5%) at the endpoint of the study. Forty of these patients (58.8%) belonged to social skills training and one patient to customary treatment (χ(2) = 41.7, df 1, p < 0.001) and when criteria for symptomatic remission and functional improvement were combined, 39 patients (97.5%) of the social skills training group and one patient (1.9%) of the customary treatment group achieved functional outcome. CONCLUSION: The results emphasize the need for psychosocial interventions as conjoint to pharmacological treatment to improve functional outcome in schizophrenia patients.

Effects of mirtazapine on the sleep wake rhythm of geriatric patients with major depression: an exploratory study with actigraphy.

INTRODUCTION: Major depression and insomnia are among the most frequent neuropsychiatric syndromes in the geriatric population. Although most SSRI antidepressants affect sleep continuity, mirtazapine has been found to improve sleep continuity in patients with depression. The aim of the present study was to assess by actigraphic recordings changes in sleep patterns of geriatric patients with major depression before and during treatment with mirtazapine (30 mg). METHODS: Patients aged 60 years or more with major depressive disorder were recruited at the outpatient service of a specialized mental health centre. Severity of depression was rated with the Montgomery-Asberg depression rating scale and subjective perception of sleep was assessed with the Pittsburgh sleep quality index (PSQI). Actigraphic parameters were registered 4 days before the onset of mirtazapine treatment (patients were drug free in this period of time) and recorded at day 60 of treatment with mirtazapine. RESULTS: A significant decrease was observed in the sleep fragmentation index. While a significant improvement was observed in the subjective assessment of quality after treatment with mirtazapine, actigraphic measures of sleep parameters did not show changes in line with mirtazapine treatment. DISCUSSION: Mirtazapine produces minimal changes on actigraphic measures in the sleep of elderly outpatients. Sleep produced by mirtazapine indicates a more pronounced effect in ≥ 80-year-old patients. This differential response should be considered during treatment of this clinical population.

The Benzodiazepine Dependence Questionnaire (BDEPQ): validity and reliability in Mexican psychiatric patients.

BACKGROUND: Benzodiazepine (BZD) dependence is a condition generally circumscribed to a therapeutic framework. Up to 44% of chronic users become dependent. The widespread use of BZD in psychiatry requires the evaluation of psychometric properties of self-reported instruments to characterize this phenomenon. OBJECTIVE: To examine the reliability, construct and criterion validity of the Benzodiazepine Dependence Questionnaire (BDEPQ) in Mexican psychiatric patients. METHOD: Patients were included if they met DSM-IV criteria for any Axis I disorder and were BZD users. A total of 150 patients were recruited. Diagnoses were made with the SCID-I and BZD dependence was determined with an adaptation of the substance dependence section of the SCID-I. All patients answered the BDEPQ. RESULTS: Almost half of the patients met criteria for BZD dependence. The BDEPQ showed adequate factor loadings with strong alpha values for the subscales and total score. A cut-off value of 23 reached the most stable sensitivity and specificity values. CONCLUSIONS: Psychometric properties of the BDEPQ in Mexican psychiatric patients support its utility as a tool for the clinical work and research as it shows to be a useful instrument for the early recognition of BZD dependence in clinical populations.

[Development and psychometric properties of a brief instrument to measure the stigma of aggressiveness in schizophrenia]. / Desarrollo y propiedades psicométricas de un instrumento breve para evaluar el estigma de agresividad en la esquizofrenia.

INTRODUCTION: Schizophrenia has been object of stigmatization throughout history. A critical component of stigma in schizophrenia is the perception that patients are extremely dangerous. The assessment of this concept in general population by the use of reliable and valid instruments will allow the development of programs aimed to reduce it. OBJECTIVE: To develop an assessment instrument of the public conception of aggressiveness in schizophrenia and to determine its reliability and validity in a community sample of Mexico City. METHOD: A total of 258 subjects completed the Public Conception of Aggressiveness Questionnaire (CAQ) which is made up of a brief clinical vignette and specific questions that assess subjective conceptions about aggressiveness and mental disorders in patients with schizophrenia. RESULTS: More than 40.0% of the sample considered that the patient with schizophrenia is aggressive and dangerous. The CAQ had an adequate internal consistency (alpha=0.74). The results of the factorial analysis showed that the two factors that explained 61.0% of the variance. DISCUSSION: The items of CAQ showed two major areas that evaluate: a) perception of presentation of aggressive behaviors and, b) mental illness recognition and social aspects of the stigma of dangerousness. The CAQ is an instrument with adequate psychometric properties that could be useful to evaluate the perception of aggressiveness in schizophrenia among general population.

Desarrollo y propiedades psicométricas de un instrumento breve para evaluar el estigma de agresividad en la esquizofrenia / Development and psychometric properties of a brief instrument to measure the stigma of aggressiveness in schizophrenia

Introducción. La esquizofrenia ha sido objeto de estigmatización a lo largo de la historia. Un componente crítico del estigma en esquizofrenia es la percepción acerca de la extrema peligrosidad de los individuos que la padecen. La evaluación de este concepto en población general mediante instrumentos válidos y confiables permitirá el desarrollo de programas dirigidos a su reducción. Objetivo. Desarrollar un instrumento de medición del concepto público de agresividad de la esquizofrenia y determinar su confiabilidad y validez en una muestra comunitaria de la Ciudad de México. Método. Un total de 258 sujetos completaron el Cuestionario de Concepto Público de Agresividad (CPA), el cual está conformado por una viñeta clínica breve y preguntas específicas que valoran la concepción subjetiva de agresividad y enfermedad mental del paciente con esquizofrenia. Resultados. Poco más del 40,0% de los sujetos entrevistados consideró agresivo y peligroso al paciente con esquizofrenia. El CPA mostró una adecuada consistencia (alpha=0,74). El análisis factorial del instrumento arrojó dos factores que explicaron el 61.0% de la varianza. Discusión. Los reactivos del CPA mostraron dos áreas principales de evaluación: a) percepción sobre la presentación de comportamientos agresivos y, b) reconocimiento de la enfermedad mental y aspectos sociales del estigma de peligrosidad. El CPA es un instrumento con adecuadas propiedades psicométricas que puede ser de utilidad para evaluar la percepción de agresividad del paciente con esquizofrenia en población abierta (AU)

Introduction. Schizophrenia has been object of stigmatization throughout history. A critical component of stigma in schizophrenia is the perception that patients are extremely dangerous. The assessment of this concept in general population by the use of reliable and valid instruments will allow the development of programs aimed to reduce it. Objective. to develop an assessment instrument of the public conception of aggressiveness in schizophrenia and to determine its reliability and validity in a community sample of Mexico City. Method. A total of 258 subjects completed the Public Conception of Aggressiveness Questionnaire (CAQ) which is made up of a brief clinical vignette and specific questions that assess subjective conceptions about aggressiveness and mental disorders in patients with schizophrenia. Results. More than 40.0% of the sample considered that the patient with schizophrenia is aggressive and dangerous. The CAQ had an adequate internal consistency (alpha=0.74). The results of the factorial analysis showed that the two factors that explained 61.0% of the variance. Discussion. The items of CAQ showed two major areas that evaluate: a) perception of presentation of aggressive behaviors and, b) mental illness recognition and social aspects of the stigma of dangerousness. The CAQ is an instrument with adequate psychometric properties that could be useful to evaluate the perception of aggressiveness in schizophrenia among general population (AU)

Traducción al español y confiabilidad del Cuestionario de Tamizaje para Síntomas Prodrómicos (PRIME Screen) / Reliability study of the translation into Spanish of the PRIME Screen Questionnaire for Prodromic Symptoms

Introducción. Una de las condiciones fundamentales para la intervención temprana en la esquizofrenia es la detección certera de los estados prodrómicos, entendido como la constelación de signos y síntomas que predicen el inicio de una psicosis en personas sin antecedentes de cuadros psicóticos. Se han desarrollado diversas entrevistas diagnósticas para la detección de sujetos con síntomas prodrómicos. Objetivo. Traducir el Cuestionario de Tamizaje de Síntomas Prodrómicos (PRIME Screen) y obtener su confiabilidad en una muestra comunitaria de adolescentes de la Ciudad de México. Método. Se incluyeron un total de 532 adolescentes de un centro de educación tecnológica industrial de la Ciudad de México. A todos los sujetos se les aplicó el Cuestionario de Tamizaje de Síntomas Prodrómicos. Resultados. El 18,4% (n=98) fueron clasificados como sujetos con presencia de uno o más síntomas prodrómicos. El análisis factorial del instrumento arrojó tres factores que explican el 59,3 % de la varianza. La consistencia interna global del instrumento fue de 0,88. Discusión. Nuestros resultados sobre el análisis factorial exploratorio muestran la agrupación de los reactivos del instrumento en tres áreas principales denominadas como: a) alteración del entorno; b) alteraciones sensoperceptiva, y c) alteración de habilidades propias. El Cuestionario de Tamizaje de Síntomas Prodrómicos es un instrumento con un adecuado comportamiento clinimétrico que puede ser efectivo para la realización de tamizajes de síntomas prodrómicos en población adolescente

Introduction. A fundamental precondition for early intervention in schizophrenia is accurate detection of prodromal states, that is, sign and symptom constellations that predict the onset of psychosis in persons with no prior background. Several structured interviews have been designed for the detection of prodromal subjects. Objective. To translate and determine the reliability of the PRIME Screen in an adolescent community sample in México City. Method. A total of 532 adolescents of a technicalindustrial educational center of México City were included for the study. All the subjects were administered the PRIME Screen Questionnaire of Prodromal Symptoms. Results. A total of 98 subjects (18.4%) reported one or more prodromal symptoms. The results of the factorial analysis showed that the PRIME Screen questionnaire is conformed by three factors that explained 59.3% of the variance. Internal consistency of the instrument was of 0.88. Discussion. Our results on the exploratory factor analysis show that the items of the questionnaire are grouped into three main areas called: a) alteration of setting; b) sensorial-perceptual abnormalities, and c) alterations of self-skills. The Prodromal Symptoms Screen Questionnaire is an instrument with adequate clinimetric behavior that may be effective to conduct community- wide screening of adolescents for prodromal symptoms

Reliability study of the translation into Spanish of the PRIME Screen Questionnaire for Prodromic Symtoms.

INTRODUCTION: A fundamental precondition for early intervention in schizophrenia is accurate detection of prodromal states, that is, sign and symptom constellations that predict the onset of psychosis in persons with no prior background. Several structured interviews have been designed for the detection of prodromal subjects. OBJECTIVE: To translate and determine the reliability of the PRIME Screen in an adolescent community sample in México City. METHOD: A total of 532 adolescents of a technical-industrial educational center of México City were included for the study. All the subjects were administered the PRIME Screen Questionnaire of Prodromal Symptoms. RESULTS: A total of 98 subjects (18.4%) reported one or more prodromal symptoms. The results of the factorial analysis showed that the PRIME Screen questionnaire is conformed by three factors that explained 59.3% of the variance. Internal consistency of the instrument was of 0.88. DISCUSSION: Our results on the exploratory factor analysis show that the items of the questionnaire are grouped into three main areas called: a) alteration of setting; b) sensorial-perceptual abnormalities, and c) alterations of self-skills. The Prodromal Symptoms Screen Questionnaire is an instrument with adequate clinimetric behavior that may be effective to conduct community-wide screening of adolescents for prodromal symptoms.

Temperament and character in violent schizophrenic patients.

UNLABELLED: Preliminary evidence shows that personality traits are important in determining violent behavior in schizophrenia. As only some patients with schizophrenia show a greater risk for violence, this risk may therefore be considered as dynamic, varying as a function of the extent to which certain personality dimensions are present and the degree to which environmental events moderate or exacerbate their expression. OBJECTIVE: To compare temperament and character dimensions between violent and non-violent schizophrenic patients and to determine which temperament and character dimensions are predictors of violent behavior in schizophrenia. METHOD: We recruited 102 schizophrenic patients without concomitant substance abuse 4 months prior to the assessment. Diagnoses were based on the SCID-I. Personality dimensions were assessed with the Temperament and Character Inventory and violent behaviors with the Overt Aggression Scale. RESULTS: Higher levels of the temperament dimension novelty seeking and a lower cooperativeness, as a character dimension, were risk factors for violent behavior in schizophrenic patients. DISCUSSION: Our data indicate that schizophrenic patients will show a greater risk for violence according to certain personality configurations and the degree to which environmental events moderate or exacerbate their expression.

[Effect to the serotonin transporter gene (5-HTT) on personality dimensions in individuals without psychopathology]. / Efecto del gen transportador de la serotonina (5-HTT) sobre las dimensiones de la personalidad en individuos sin psicopatología.

INTRODUCTION: The aim of the present study was to assess the association between the serotonin transporter gene and the Temperament and Character Inventory (TCI) personality dimensions in subjects without psychopathology. METHOD: Fifty seven individuals without psychiatric symptoms were assessed with the SCL-90, and the TCI. In all subjects a peripheral blood sample was taken to determine their genotypes, after informed consent. Three groups were formed according to the 5-HTT genotype: SS, SL and LL, and the TCI results were compared. RESULTS: There was no association among the 5-HTT genotypes and any of the TCI subscales. There were also no statistical differences among any of the three groups divided by genotype only according to the TCI scores, as well as when compared with historical controls. CONCLUSIONS: These results are consistent with other studies that have not found associations among the different measurements of personality and 5-HTT genotypes. Likewise, our data suggest that our sample can be useful as a source of controls for later studies. This is the first study assessing TCI dimensions and the 5-HTT gene in the Mexican population.

Efecto del gen del transportador de la serotonina (5-HTT) sobre las dimensiones de la personalidad en individuos sin psicopatología / Effect to the serotonin transporter gene (5-HTT) on personality dimensions in individuals without psychopathology

Introducción. El presente estudio se realizó con el fin de estudiar el efecto de los genotipos moleculares del transportador de la serotonina (5-HTT) sobre las dimensiones de la personalidad basadas en el Inventario de Temperamento y Carácter (ITC) en personas sin presencia de psicopatología. Métodos. Participaron 57 individuos sin sintomatología psiquiátrica evaluados mediante el SCL-90 y que respondieron además el ITC. A todos se les tomó una muestra de sangre periférica para la determinación de sus genotipos previo consentimiento informado. Se formaron tres grupos según el genotipo del 5-HTT: SS, SL y LL, y se compararon los resultados del ITC entre cada grupo. Resultados. No se encontró relación entre los genotipos del 5-HTT y ninguna de las subescalas del ITC. Tampoco se pudieron demostrar diferencias entre ninguno de los tres grupos de acuerdo únicamente a las puntuaciones del ITC en comparación con ellos mismos, ni con un grupo de controles históricos publicados anteriormente. Conclusiones. Los resultados son consistentes con otros estudios en los que no se han encontrado asociaciones entre las diferentes medidas de la personalidad y los genotipos del 5-HTT. Asimismo, los datos sugieren que la muestra que participó en el presente estudio puede utilizarse como una fuente de controles para estudios posteriores. Éste es el primer estudio de asociación entre la personalidad y el gen del 5-HTT que se hace en la población mexicana

Introduction. The aim of the present study was to assess the association between the serotonin transporter gene and the Temperament and Character Inventory (TCI) personality dimensions in subjects without psychopathology. Method. Fifty seven individuals without psychiatric symptoms were assessed with the SCL-90, and the TCI. In all subjects a peripheral blood sample was taken to determine their genotypes, after informed consent. Three groups were formed according to the 5-HTT genotype: SS, SL and LL, and the TCI results were compared. Results. There was no association among the 5-HTT genotypes and any of the TCI subscales. There were also no statistical differences among any of the three groups divided by genotype only according to the TCI scores, as well as when compared with historical controls. Conclusions. These results are consistent with other studies that have not found associations among the different measurements of personality and 5-HTT genotypes. Likewise, our data suggest that our sample can be useful as a source of controls for later studies. This is the first study assessing TCI dimensions and the 5-HTT gene in the Mexican population

[Interrater reliability of the Spanish version of Schedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime version (K-SADS-PL)]. / Estudio de fiabilidad interevaluador de la versión en español de la entrevista Schedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime version (K-SADS-PL).

INTRODUCTION: The K-SADS-PL diagnostic interview is useful for the cross-sectional and longitudinal evaluation of psychopathology in children and adolescents. The objective of this article was to describe the interrater reliability of the Spanish version of the Schedule for Affective Disorders and Schizophrenia for School-Age Children--Present and Lifetime version (K-SADS-PL). METHOD: The interview was translated, back-translated and adapted to Spanish. Forty psychiatric outpatients (aged 6 to 17 years) were evaluated. The interviews were videotaped and scored by three independent raters. All of them included both the child's and parent's interview. Interrater reliability was obtained for affective, anxiety and conduct disorders using the Cohen's kappa coefficient. RESULTS: Kappa coefficients were between the good and excellent range for present and lifetime disorders (major depressive disorder kappa = 0.76, any anxiety disorder kappa = 0.84, attention deficit hyperactivity disorder kappa = 0.91 and conduct disorder, kappa = 1). CONCLUSION: The Spanish version of the K-SADS-PL is a reliable instrument for the assessment of psychopathology in children and adolescents.

Estudio de fiabilidad interevaluador de la versión en español de la entrevista Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL) / Interrater reliability of the Spanish version of Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL)

Introducción. La entrevista diagnóstica K-SADS-PL constituye un instrumento adecuado para evaluar la psicopatología de niños y de adolescentes transversal y longitudinalmente. El objetivo de este trabajo fue determinar la fiabilidad interevaluador de la versión en español de la entrevista K-SADS-PL. Método. Se realizó la traducción al español, retraducción al inglés y adaptación de la entrevista. Se evaluaron 40 pacientes de 6 a 17 años que acudieron a tres instituciones públicas de atención psiquiátrica. Las entrevistas a los pacientes y sus padres se videograbaron y calificaron por tres evaluadores independientes. Se obtuvieron los coeficientes kappa para la fiabilidad interevaluador. Resultados. Se obtuvieron coeficientes kappa de buenos a excelentes para trastorno depresivo mayor k = 0.76, cualquier trastorno ansioso k =0.84, trastorno por déficit de atención con hiperactividad k =0.9 y trastorno disocial k =1. Conclusiones. La versión en español de la entrevista K-SADS-PL es un instrumento fiable para diagnosticar la psicopatología de niños y adolescentes

Introduction. The K-SADS-PL diagnostic interview is useful for the cross-sectional and longitudinal evaluation of psychopathology in children and adolescents. The objective of this article was to describe the interrater reliability of the Spanish version of the Schedule for Affective Disorders and Schizophrenia for School-Age Children- Present and Lifetime version (K-SADS-PL). Method. The interview was translated, back-translated and adapted to Spanish. Forty psychiatric outpatients (aged 6 to 17 years) were evaluated. The interviews were videotaped and scored by three independent raters. All of them included both the child’s and parent’s interview. Interrater reliability was obtained for affective, anxiety and conduct disorders using the Cohen’s kappa coefficient. Results. Kappa coefficients were between the good and excellent range for present and lifetime disorders (major depressive disorder k = 0.76, any anxiety disorder k = 0.84, attention deficit hyperactivity disorder k = 0.91 and conduct disorder, k = 1). Conclusion. The Spanish version of the K-SADS-PL is a reliable instrument for the assessment of psychopathology in children and adolescents

Reproducción de un modelo informático de las alucinaciones auditivas en la esquizofrenia / Replication of a computer model of auditory hallucinations in schizophrenia

Introducción. El podado sináptico anormal ha sido propuesto por algunos autores como una teoría para explicar a la esquizofrenia y ha sido estudiado de diversas maneras. Entre las aproximaciones al estudio de este fenómeno se ha utilizado la simulación informática. Métodos. Se utilizó un ordenador PC y los programas informáticos MATLAB versión 5.3 y Neural Networks Toolbox. Para la reproducción del modelo se utilizó la red de Elman para la unidad neuronal y la red publicada por McGlashan y Hoffman. Resultados. A medida que se eliminaron las sinapsis el porcentaje correcto de detección aumentó del 68 al 91 %, llegando a la cima cuando hubo una eliminación aproximada del 60 %. Cuando se continuó con la eliminación disminuyó la capacidad de detección y se presentaron palabras en la ausencia de una entrada, lo cual se consideró como una alucinación. Éstas se presentaron con mayor frecuencia cuando el podado alcanzó entre el 80 y 95 %. Conclusiones. El modelo de simulación por ordenador no sólo provee un modelo para la formación de síntomas, sino también un entendimiento de la utilidad adaptativa del podado. Cuando las unidades neuronales, en vez de las conexiones, fueron eliminadas sólo se obtuvo un empeoramiento progresivo de la percepción. Esto confirma la hipótesis propuesta de que la fisiopatología de la esquizofrenia subyace en la conexión entre las neuronas y no en las neuronas mismas

Introduction. Abnormal synaptic pruning has been proposed by some authors as a theory to explain schizophrenia. It has been studied in different ways, some of which are computerized models. Methods. A PC computer with MATLAB version 5.3 and Neural Networks Toolbox programs were used. To reproduce the model we used Elman’s network for neuronal unit and McGlashan and Hoffman’s network. Results. The corrected percentage of detection improved as synapses were prunned. It increased from 68% to 91 %, reaching the highest detection level when 60% of the synapses were eliminated. Detection capacity was reduced when synaptic elimination continued and the program started detecting words in the absence of input. This was considered as a hallucination. When pruning reached from 80% to 95%, hallucinations occurred more frequently. Conclusions. The computer simulation model provides a symptom formation model, and also a way of understanding pruning’s adaptative utility. When the neuronal units were eliminated (instead of connections), there was only progressive worsening in word perception. This confirms the hypothesis proposed that schizophrenia pathophysiology underlies neuronal connections, not the neurons

Características sociodemográficas asociadas a la conducta violenta en la esquizofrenia / Sociodemographic features related to violent behavior in schizophrenia

Introducción. Se ha propuesto que algunas variables sociodemográficas pueden predecir el comportamiento violento en pacientes con esquizofrenia. El objetivo del presente estudio es investigar la relación de las variables sociodemográficas y clínicas del padecimiento con la conducta violenta en pacientes con esquizofrenia. Método. Se incluyeron 106 pacientes con el diagnóstico de esquizofrenia. Se registraron las principales características demográficas y clínicas de cada uno de los pacientes en un formato diseñado previamente. Se utilizó la Escala de Agresión Explícita (EAE) para la evaluación de la conducta violenta. Resultados. El 49,1 % de los pacientes fueron clasificados como violentos. El estado civil, el abuso de alcohol, el número de hospitalizaciones psiquiátricas previas y la edad de la primera hospitalización fueron variables predictoras para la conducta violenta en esquizofrenia. Discusión. Las variables sociodemográficas predictoras de violencia en esquizofrenia son fáciles de evaluar en la primera entrevista con el paciente y pueden ser de utilidad para prevenir conductas violentas posteriores

Introduction. It has been proposed that some sociodemographic variables may predict violent behavior in schizophrenic patients. The aim of this study was to investigate the relationship of violent behavior with sociodemographic and clinical features in schizophrenic patients. Method. We included 106 schizophrenic patients. Sociodemographic and clinical characteristics of each patient were recorded in a previously designed record. Violent behaviors were assessed with the Overt Aggression Scale (OAS). Results. From the total sample, 49.1 % of the patients were classified as violent. Marital status, alcohol abuse, number of previous psychiatric hospitalizations and age of first hospitalization were predictive variables for violent behavior in schizophrenia. Discussion. Predictive sociodemographic variables for violence in schizophrenia are easy to measure during the first interview with the patient and can be useful for the prevention of future violence

[Sociodemographic features related to violent behavior in schizophrenia]. / Características sociodemográficas asociadas a la conducta violenta en la esquizofrenia.

INTRODUCTION: It has been proposed that some sociodemographic variables may predict violent behavior in schizophrenic patients. The aim of this study was to investigate the relationship of violent behavior with sociodemographic and clinical features in schizophrenic patients. METHOD: We included 106 schizophrenic patients. Sociodemographic and clinical characteristics of each patient were recorded in a previously designed record. Violent behaviors were assessed with the Overt Aggression Scale (OAS). RESULTS: From the total sample, 49.1 % of the patients were classified as violent. Marital status, alcohol abuse, number of previous psychiatric hospitalizations and age of first hospitalization were predictive variables for violent behavior in schizophrenia. DISCUSSION: Predictive sociodemographic variables for violence in schizophrenia are easy to measure during the first interview with the patient and can be useful for the prevention of future violence.

[Replication of a computer model of auditory hallucinations in schizophrenia]. / Reproducción de un modelo informático de las alucinaciones auditivas en la esquizofrenia.

INTRODUCTION: Abnormal synaptic pruning has been proposed by some authors as a theory to explain schizophrenia. It has been studied in different ways, some of which are computerized models. METHODS: A PC computer with MATLAB version 5.3 and Neural Networks Toolbox programs were used. To reproduce the model we used Elman's network for neuronal unit and McGlashan and Hoffman's network. RESULTS: The corrected percentage of detection improved as synapses were prunned. It increased from 68% to 91 %, reaching the highest detection level when 60% of the synapses were eliminated. Detection capacity was reduced when synaptic elimination continued and the program started detecting words in the absence of input. This was considered as a hallucination. When pruning reached from 80% to 95%, hallucinations occurred more frequently. CONCLUSIONS: The computer simulation model provides a symptom formation model, and also a way of understanding pruning's adaptative utility. When the neuronal units were eliminated (instead of connections), there was only progressive worsening in word perception. This confirms the hypothesis proposed that schizophrenia pathophysiology underlies neuronal connections, not the neurons.

Frontal and limbic metabolic differences in subjects selected according to genetic variation of the SLC6A4 gene polymorphism.

Allelic variants in the promoter region of the serotonin transporter (5-HTT) gene have been implicated in several psychiatric disorders and personality traits. In particular, two common alleles in a variable repeat sequence of the promoter region (SLC6A4) have been differentially associated with a display of abnormal levels of anxiety and affective illness in individuals carrying the "s" allele. The aim of this study was to compare the basal cerebral metabolic activity of non-psychiatric subjects in fronto-limbic structures to determine whether differences exist in basal metabolic activity within this functional polymorphism. PET scans with fluorine-18 fluorodeoxyglucose as radiotracer were performed in 71 non-psychiatric subjects previously screened for psychopathology and subsequently genotyped for SLC6A4; PET images were compared with SPM2 according to s/s (n = 27), s/l (n = 25), and l/l (n = 19) groups considering a significance threshold in a priori selected areas of P < 0.001 and an extent threshold > or =5 voxels. The analysis showed an effect of interest among the three genotype groups in right anterior cingulate gyrus (ACC), left middle frontal gyrus, and left posterior cingulate gyrus (PCC). Comparison between l/l vs. s/s showed increased metabolism for l/l in left middle frontal gyrus and an increase for s/s in right ACC and left PCC. Comparison between s/s vs. s/l showed an increase for s/s in left PCC and right ACC. Increased basal metabolism in fronto-limbic structures for the s/s group may be conceived as an "overactive metabolic state" of these structures, possibly related to an increased susceptibility for developing an anxiety-depression spectrum disorder.

A forced five-dimensional factor analysis and concurrent validity of the Positive and Negative Syndrome Scale in Mexican schizophrenic patients.

UNLABELLED: The heterogeneity of schizophrenic symptomatology is well documented. The positive-negative distinction is limited to cover the entire spectrum of schizophrenic psychopathology in order to describe the various clinical aspects of the disorder. METHOD: We recruited 150 schizophrenic patients between May 2002 and September 2003. Diagnoses were based on a structured clinical interview. The Positive and Negative Syndrome Scale (PANSS) was used to evaluate general psychopathology and symptom severity. For the concurrent validity of the pentagonal model of the PANSS, the BPRS, the CDSS, the OAS and the MMSE were used. RESULTS: The forced five-factor principal-component analysis explained 53.4% of the total variance. There were significant correlations between the clinical rating scales and the five components of the PANSS. DISCUSSION: Our data support a pentagonal model underlying the multidimensional schizophrenic symptomatology as assessed by the PANSS. The five-factor structure of the PANSS in Mexican schizophrenic patients enables further elucidation of the various clinical aspects of schizophrenia.