Browsing by Author "Crossley, Nicolas"
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Publication Differences of affective and non-affective psychoses in early intervention services from Latin America(2022) Cerqueira, Raphael; Ziebold, Carolina; Cavalcante, Daniel; Oliveira, Giovany; Vásquez, Javiera; Undurraga, Juan; González, Alfonso; Nachar, Ruben; López, Carlos; Noto, Cristiano; Crossley, Nicolas; Gadelha, AryBackground: Psychosis presentation can be affected by genetic and environmental factors. Differentiating between affective and non-affective psychosis (A-FEP and NA-FEP, respectively) may influence treatment decisions and clinical outcomes. The objective of this paper is to examine differences between patients with A-FEP or NA-FEP in a Latin American sample. Methods: Patients from two cohorts of patients with a FEP recruited from Brazil and Chile. Subjects included were aged between 15 and 30 years, with an A-FEP or NA-FEP (schizophrenia-spectrum disorders) according to DSM-IV-TR. Sociodemographic data, duration of untreated psychosis and psychotic/mood symptoms were assessed. Generalized estimating equation models were used to assess clinical changes between baseline-follow-up according to diagnosis status. Results: A total of 265 subjects were included. Most of the subjects were male (70.9 %), mean age was 21.36 years. A-FEP and NA-FEP groups were similar in almost all sociodemographic variables, but A-FEP patients had a higher probability of being female. At baseline, the A-FEP group had more manic symptoms and a steeper reduction in manic symptoms scores during the follow- up. The NA-FEP group had more negative symptoms at baseline and a higher improvement during follow-up. All domains of The Positive and Negative Syndrome Scale improved for both groups. No difference for DUP and depression z-scores at baseline and follow-up. Limitations: The sample was recruited at tertiary hospitals, which may bias the sample towards more severe cases. Conclusions: This is the largest cohort comparing A-FEP and NA-FEP in Latin America. We found that features in FEP patients could be used to improve diagnosis and support treatment decisions.Publication Dysconnectivity in Schizophrenia Revisited: Abnormal Temporal Organization of Dynamic Functional Connectivity in Patients With a First Episode of Psychosis(2022) Ramírez, Juan; Tepper, Ángeles; Alliende, Luz; Mena, Carlos; Castañeda, Carmen; Iruretagoyena, Bárbara; Nachar, Ruben; Reyes, Francisco; León, Pablo; Mora, Ricardo; Ossandon, Tomas; González, Alfonso; Undurraga, Juan; De la Fuente, Camilo; Crossley, NicolasBackground and hypothesis: Abnormal functional connectivity between brain regions is a consistent finding in schizophrenia, including functional magnetic resonance imaging (fMRI) studies. Recent studies have highlighted that connectivity changes in time in healthy subjects. We here examined the temporal changes in functional connectivity in patients with a first episode of psychosis (FEP). Specifically, we analyzed the temporal order in which whole-brain organization states were visited. Study design: Two case-control studies, including in each sample a subgroup scanned a second time after treatment. Chilean sample included 79 patients with a FEP and 83 healthy controls. Mexican sample included 21 antipsychotic-naïve FEP patients and 15 healthy controls. Characteristics of the temporal trajectories between whole-brain functional connectivity meta-states were examined via resting-state functional MRI using elements of network science. We compared the cohorts of cases and controls and explored their differences as well as potential associations with symptoms, cognition, and antipsychotic medication doses. Study results: We found that the temporal sequence in which patients' brain dynamics visited the different states was more redundant and segregated. Patients were less flexible than controls in changing their network in time from different configurations, and explored the whole landscape of possible states in a less efficient way. These changes were related to the dose of antipsychotics the patients were receiving. We replicated the relationship with antipsychotic medication in the antipsychotic-naïve FEP sample scanned before and after treatment. Conclusions: We conclude that psychosis is related to a temporal disorganization of the brain's dynamic functional connectivity, and this is associated with antipsychotic medication use.Item High prevalence of metabolic alterations in Latin American patients at initial stages of psychosis(John Wiley & Sons, Inc., 2020) Iruretagoyena, Bárbara; Castañeda, Carmen; Undurraga, Juan; Nachar, Rubén; Mena, Cristian; Gallardo, Carlos; Crossley, Nicolas; Gonzalez-Valderrama, AlfonsoAim Studies conducted in the United States have highlighted a higher prevalence of metabolic alterations (MA) in Latino population and Latino psychotic patients. Metabolic risk in psychosis is known to be present from initial stages of the disease. To better characterize this population, we explored the prevalence of MA and metabolic syndrome (MS) in early psychosis patients in a Latin American country. Methods Transversal, observational study comparing the prevalence of MA and MS in patients with early psychosis from an outpatient program in Chile (n = 148) with a community representative sample from the 2009‐2010 National Health Survey (n = 568). ANOVA and regression analysis were performed obtaining odds ratio for MA and MS. Results The prevalence of MS was 44.7% in patients compared to 11.4% in the community sample (odds ratio [OR] 5.28, confidence interval [CI] 95% 3.07‐9.08; P‐value <0.001). There was no effect of gender. Subgroup analyses showed no significant association of MS with clozapine/olanzapine use, treatment duration or tobacco use. There was an association between treatment duration and hypertriglyceridemia (P = 0.024; OR 1.02, CI 95% 1.00‐1.04) and obesity (P = 0.007; OR 5.93, CI 95% 1.82‐20.22). Clozapine/olanzapine use was associated with hyperglycaemia (P = 0.007; OR 6.04, CI 95% 1.63‐22.38) and high low density lipoprotein (P = 0.033 ANOVA; OR 5.28, CI 95% 1.14‐24.37). Conclusion Latino psychotic patients have a high risk of MA and MS at initial stages of the disease which is not entirely explained by the higher risk in the whole Latino population, is irrespective of gender, and does not seem to be entirely a response to atypical antipsychotic use.Publication Obesity and brain structure in schizophrenia - ENIGMA study in 3021 individuals(2022) McWhinney, Sean; Brosch, Katharina; Calhoun, Vince; Crespo, Benedicto; Crossley, Nicolas; Dannlowski, Udo; Dickie, Erin; Dietze, Lorielle; Donohoe, Gary; Du Plessis, Stefan; Ehrlich, Stefan; Emsley, Robin; Furstova. Petra; Glahn, David; Gonzalez, Alfonso; Grotegerd, Dominik; Nenadić , Igor; Ope, Nils; Pfarr, Julia; Rodrigue, Amanda; Stein, Frederike; Švance, Patrik; Tordesillas, Diana; Undurraga, Juan; Vázquez, Javier; Voineskos, Aristotle; Walton, Esther; Weickert, Thomas; Shannon, Cynthia; Thompson, Paul; Van Erp, Theo; Turner, Jessica; Hajek, TomasSchizophrenia is frequently associated with obesity, which is linked with neurostructural alterations. Yet, we do not understand how the brain correlates of obesity map onto the brain changes in schizophrenia. We obtained MRI-derived brain cortical and subcortical measures and body mass index (BMI) from 1260 individuals with schizophrenia and 1761 controls from 12 independent research sites within the ENIGMA-Schizophrenia Working Group. We jointly modeled the statistical effects of schizophrenia and BMI using mixed effects. BMI was additively associated with structure of many of the same brain regions as schizophrenia, but the cortical and subcortical alterations in schizophrenia were more widespread and pronounced. Both BMI and schizophrenia were primarily associated with changes in cortical thickness, with fewer correlates in surface area. While, BMI was negatively associated with cortical thickness, the significant associations between BMI and surface area or subcortical volumes were positive. Lastly, the brain correlates of obesity were replicated among large studies and closely resembled neurostructural changes in major depressive disorders. We confirmed widespread associations between BMI and brain structure in individuals with schizophrenia. People with both obesity and schizophrenia showed more pronounced brain alterations than people with only one of these conditions. Obesity appears to be a relevant factor which could account for heterogeneity of brain imaging findings and for differences in brain imaging outcomes among people with schizophrenia.Publication Source-based morphometry reveals structural brain pattern abnormalities in 22q11.2 deletion syndrome(2024) Repetto, Gabriela; Ge, Ruiyang; Ching, Christopher; Bassett, Anne; Kushan, Leila; Antshe, Kevin; Van Amelsvoort, Therese; Bakker, Geor; Butcher, Nancy; Campbell, Linda; Chow, Eva; Craig, Michael; Crossley, Nicolas; Cunningham, Adam; Daly, Eileen; Doherty, Joanne; Durdle, Courtney; Emanuel, Beverly; Fiksinski, Ania; Forsyth, Jennifer; Fremont, Wanda; Goodrich-Hunsaker, Naomi; Gudbrandsen, Maria; Gur, Raquel; Jalbrzikowski, Maria; Kates, Wendy; Lin, Amy; Linden, David; McCabe, Kathryn; McDonald, Donna; Moss, Hayley; Murphy, Declan; Murphy, Kieran; Owen, Michael; Villalon, Julio; Roalf, David; Ruparel, Kosha; Schmitt, J. Eric; Schuite, Sanne; Angkustsiri, Kathleen22q11.2 deletion syndrome (22q11DS) is the most frequently occurring microdeletion in humans. It is associated with a significant impact on brain structure, including prominent reductions in gray matter volume (GMV), and neuropsychiatric manifestations, including cognitive impairment and psychosis. It is unclear whether GMV alterations in 22q11DS occur according to distinct structural patterns. Then, 783 participants (470 with 22q11DS: 51% females, mean age [SD] 18.2 [9.2]; and 313 typically developing [TD] controls: 46% females, mean age 18.0 [8.6]) from 13 datasets were included in the present study. We segmented structural T1-weighted brain MRI scans and extracted GMV images, which were then utilized in a novel source-based morphometry (SBM) pipeline (SS-Detect) to generate structural brain patterns (SBPs) that capture co-varying GMV. We investigated the impact of the 22q11.2 deletion, deletion size, intelligence quotient, and psychosis on the SBPs. Seventeen GMV-SBPs were derived, which provided spatial patterns of GMV covariance associated with a quantitative metric (i.e., loading score) for analysis. Patterns of topographically widespread differences in GMV covariance, including the cerebellum, discriminated individuals with 22q11DS from healthy controls. The spatial extents of the SBPs that revealed disparities between individuals with 22q11DS and controls were consistent with the findings of the univariate voxel-based morphometry analysis. Larger deletion size was associated with significantly lower GMV in frontal and occipital SBPs; however, history of psychosis did not show a strong relationship with these covariance patterns. 22q11DS is associated with distinct structural abnormalities captured by topographical GMV covariance patterns that include the cerebellum. Findings indicate that structural anomalies in 22q11DS manifest in a nonrandom manner and in distinct covarying anatomical patterns, rather than a diffuse global process. These SBP abnormalities converge with previously reported cortical surface area abnormalities, suggesting disturbances of early neurodevelopment as the most likely underlying mechanism.Item Structural brain abnormalities in schizophrenia in adverse environments: examining the effect of poverty and violence in six Latin American cities(2021) Crossley, Nicolas; Zugman, Andre; Reyes, Francisco; Czepielewski, Leticia; Castro, Mariana; Diaz, Ana; Pineda, Julian; Reckziegel, Ramiro; Gadelha, Ary; Jackowski, Andrea; Noto, Cristiano; Alliende, Luz; Iruretagoyena, Bárbara; Ossandon, Tomas; Ramírez, Juan; Castañeda, Carmen; González, Alfonso; Nachar, Ruben; León, Pablo; Undurraga, Juan; De la Fuente, Camilo; Bressan, Rodrigo; ANDES NetworkBackground: Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear. Aims: We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed. Method: This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model. Results: A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = -0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure. Conclusions: Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.