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Duration of untreated psychosis and acute remission of negative symptoms in a South American first-episode psychosis cohort

2017 , Alfonso González-Valderrama , Carmen Paz Castañeda , Cristián Mena , Juan Undurraga , Pilar Mondaca , Matías Yañez , Paula Bedregal , Ruben Nachar

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Implementing Psychosocial Evidence-Based Practices in Mental Health: Are We Moving in the Right Direction?

2015 , Alfonso González-Valderrama , Cristián Mena , Juan Undurraga , Carlos Gallardo , Pilar Mondaca

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Effects of socioeconomic status in cognition of people with schizophrenia: results from a Latin American collaboration network with 1175 subjects

2021 , Letícia Sanguinetti Czepielewski , Luz Maria Alliende , Carmen Paz Castañeda , Mariana Castro , Salvador M. Guinjoan , Raffael Massuda , Arthur A. Berberian , Ana Olivia Fonseca , Ary Gadelha , Rodrigo Bressan , Marisa Crivelaro , Mario Louzã , UNDURRAGA FOURCADE, JUAN PABLO , Alfonso González-Valderrama , Rubén Nachar , Rodrigo R. Nieto , Cristian Montes , Hernan Silva , Álvaro I. Langer , Carlos Schmidt , Rocío Mayol-Troncoso , Ana M. Díaz-Zuluaga , Johanna Valencia-Echeverry , Carlos López-Jaramillo , Rodolfo Solís-Vivanco , Francisco Reyes-Madrigal , Camilo de la Fuente-Sandoval , Nicolás A. Crossley , Clarissa S. Gama

AbstractBackgroundCognition heavily relies on social determinants and genetic background. Latin America comprises approximately 8% of the global population and faces unique challenges, many derived from specific demographic and socioeconomic variables, such as violence and inequality. While such factors have been described to influence mental health outcomes, no large-scale studies with Latin American population have been carried out. Therefore, we aim to describe the cognitive performance of a representative sample of Latin American individuals with schizophrenia and its relationship to clinical factors. Additionally, we aim to investigate how socioeconomic status (SES) relates to cognitive performance in patients and controls.MethodsWe included 1175 participants from five Latin American countries (Argentina, Brazil, Chile, Colombia, and Mexico): 864 individuals with schizophrenia and 311 unaffected subjects. All participants were part of projects that included cognitive evaluation with MATRICS Consensus Cognitive Battery and clinical assessments.ResultsPatients showed worse cognitive performance than controls across all domains. Age and diagnosis were independent predictors, indicating similar trajectories of cognitive aging for both patients and controls. The SES factors of education, parental education, and income were more related to cognition in patients than in controls. Cognition was also influenced by symptomatology.ConclusionsPatients did not show evidence of accelerated cognitive aging; however, they were most impacted by a lower SES suggestive of deprived environment than controls. These findings highlight the vulnerability of cognitive capacity in individuals with psychosis in face of demographic and socioeconomic factors in low- and middle-income countries.

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Imaging Social and Environmental Factors as Modulators of Brain Dysfunction: Time to Focus on Developing Non-Western Societies

2019 , Nicolas A. Crossley , Luz Maria Alliende , Tomas Ossandon , Carmen Paz Castañeda , Alfonso González-Valderrama , UNDURRAGA FOURCADE, JUAN PABLO , Mariana Castro , Salvador Guinjoan , Ana M. Díaz-Zuluaga , Julián A. Pineda-Zapata , Carlos López-Jaramillo , Francisco Reyes-Madrigal , Pablo León-Ortíz , Camilo de la Fuente-Sandoval , Leticia Sanguinetti Czepielewski , Clarissa S. Gama , Andre Zugman , Ary Gadelha , Andrea Jackowski , Rodrigo Bressan

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Functional Dysconnectivity in Ventral Striatocortical Systems in 22q11.2 Deletion Syndrome

2021 , Ángeles Tepper , Analía Cuiza , Luz María Alliende , Carlos Mena , Juan Pablo Ramirez-Mahaluf , Barbara Iruretagoyena , Claudia Ornstein , Rosemarie Fritsch , Ruben Nachar , Alfonso González-Valderrama , UNDURRAGA FOURCADE, JUAN PABLO , Juan Pablo Cruz , Cristian Tejos , Alex Fornito , REPETTO LISBOA, MARIA GABRIELA , Nicolas Crossley

Abstract 22q11.2 deletion syndrome (22q11.2DS) is a genetic neurodevelopmental disorder that represents one of the greatest known risk factors for psychosis. Previous studies in psychotic subjects without the deletion have identified a dopaminergic dysfunction in striatal regions, and dysconnectivity of striatocortical systems, as an important mechanism in the emergence of psychosis. Here, we used resting-state functional MRI to examine striatocortical functional connectivity in 22q11.2DS patients. We used a 2 × 2 factorial design including 125 subjects (55 healthy controls, 28 22q11.2DS patients without a history of psychosis, 10 22q11.2DS patients with a history of psychosis, and 32 subjects with a history of psychosis without the deletion), allowing us to identify network effects related to the deletion and to the presence of psychosis. In line with previous results from psychotic patients without 22q11.2DS, we found that there was a dorsal to ventral gradient of hypo- to hyperstriatocortical connectivity related to psychosis across both patient groups. The 22q11.2DS was additionally associated with abnormal functional connectivity in ventral striatocortical networks, with no significant differences identified in the dorsal system. Abnormalities in the ventral striatocortical system observed in these individuals with high genetic risk to psychosis may thus reflect a marker of illness risk.

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Intra and inter-individual variability in functional connectomes of patients with First Episode of Psychosis

2023 , Ángeles Tepper , Javiera Vásquez Núñez , Juan Pablo Ramirez-Mahaluf , Juan Manuel Aguirre , Daniella Barbagelata , Elisa Maldonado , Camila Díaz Dellarossa , Ruben Nachar , Alfonso González-Valderrama , UNDURRAGA FOURCADE, JUAN PABLO , Joaquín Goñi , Nicolás Crossley

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Uso de cannabis en jóvenes hospitalizados por un primer episodio de psicosis: un estudio caso-control

2020 , Carmen Paz Castañeda , Luz María Alliende , Bárbara Iruretagoyena , Rubén Nachar , Felipe Mancilla , Camila Díaz , Carlos Gallardo , Cristián Mena , Juan Pablo Ramírez-Mahaluf , UNDURRAGA FOURCADE, JUAN PABLO , Alfonso González-Valderrama , Nicolás A. Crossley

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Differences of affective and non-affective psychoses in early intervention services from Latin America

2022 , Raphael O. Cerqueira , Carolina Ziebold , Daniel Cavalcante , Giovany Oliveira , Javiera Vásquez , UNDURRAGA FOURCADE, JUAN PABLO , Alfonso González-Valderrama , Ruben Nachar , Carlos Lopez-Jaramillo , Cristiano Noto , Nicolas Crossley , Ary Gadelha

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Predictors of clozapine discontinuation at 2 years in treatment-resistant schizophrenia

2021 , Barbara Iruretagoyena , Carmen Paz Castañeda , Cristian Mena , Camila Diaz , Ruben Nachar , Juan Pablo Ramirez-Mahaluf , Alfonso González-Valderrama , Juan Undurraga , James H. Maccabe , Nicolas A. Crossley

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The incidence of non-affective psychotic disorders in Chile between 2005 and 2018: results from a national register of over 30 000 cases

2020 , Alfonso González-Valderrama , Hannah E. Jongsma , Cristián Mena , Carmen Paz Castañeda , Rubén Nachar , UNDURRAGA FOURCADE, JUAN PABLO , Nicolás Crossley , David Aceituno , Barbara Iruretagoyena , Carlos Gallardo , Pilar Mondaca , Matías Monje , Matías Irarrazaval , Cynthia Zavala , Lucia Valmaggia , James B. Kirkbride

AbstractBackgroundEvidence suggests the incidence of non-affective psychotic disorders (NAPDs) varies across persons and places, but data from the Global South is scarce. We aimed to estimate the treated incidence of NAPD in Chile, and variance by person, place and time.MethodsWe used national register data from Chile including all people, 10–65 years, with the first episode of NAPD (International Classification of Diseases, Tenth Revision: F20–F29) between 1 January 2005 and 29 August 2018. Denominators were estimated from Chilean National Census data. Our main outcome was treated incidence of NAPD and age group, sex, calendar year and regional-level population density, multidimensional poverty and latitude were exposures of interest.ResultsWe identified 32 358 NAPD cases [12 136 (39.5%) women; median age-at-first-contact: 24 years (interquartile range 18–39 years)] during 171.1 million person-years [crude incidence: 18.9 per 100 000 person-years; 95% confidence interval (CI) 18.7–19.1]. Multilevel Poisson regression identified a strong age–sex interaction in incidence, with rates peaking in men (57.6 per 100 000 person-years; 95% CI 56.0–59.2) and women (29.5 per 100 000 person-years; 95% CI 28.4–30.7) between 15 and 19 years old. Rates also decreased (non-linearly) over time for women, but not men. We observed a non-linear association with multidimensional poverty and latitude, with the highest rates in the poorest regions and those immediately south of Santiago; no association with regional population density was observed.ConclusionOur findings inform the aetiology of NAPDs, replicating typical associations with age, sex and multidimensional poverty in a Global South context. The absence of association with population density suggests this risk may be context-dependent.