Country-level gender inequality is associated with structural differences in the brains of women and men

男女間の不平等と脳の性差 --男女間の不平等は脳構造の性差と関連する--. 京都大学プレスリリース. 2023-05-10.Gender inequality across the world has been associated with a higher risk to mental health problems and lower academic achievement in women compared to men. We also know that the brain is shaped by nurturing and adverse socio-environmental experiences. Therefore, unequal exposure to harsher conditions for women compared to men in gender-unequal countries might be reflected in differences in their brain structure, and this could be the neural mechanism partly explaining women’s worse outcomes in gender-unequal countries. We examined this through a random-effects meta-analysis on cortical thickness and surface area differences between adult healthy men and women, including a meta-regression in which country-level gender inequality acted as an explanatory variable for the observed differences. A total of 139 samples from 29 different countries, totaling 7, 876 MRI scans, were included. Thickness of the right hemisphere, and particularly the right caudal anterior cingulate, right medial orbitofrontal, and left lateral occipital cortex, presented no differences or even thicker regional cortices in women compared to men in gender-equal countries, reversing to thinner cortices in countries with greater gender inequality. These results point to the potentially hazardous effect of gender inequality on women’s brains and provide initial evidence for neuroscience-informed policies for gender equality

Country-level gender inequality is associated with structural differences in the brains of women and men

Gender inequality across the world has been associated with a higher risk to mental health problems and lower academic achievement in women compared to men. We also know that the brain is shaped by nurturing and adverse socio-environmental experiences. Therefore, unequal exposure to harsher conditions for women compared to men in gender-unequal countries might be reflected in differences in their brain structure, and this could be the neural mechanism partly explaining women's worse outcomes in gender-unequal countries. We examined this through a random-effects meta-analysis on cortical thickness and surface area differences between adult healthy men and women, including a meta-regression in which country-level gender inequality acted as an explanatory variable for the observed differences. A total of 139 samples from 29 different countries, totaling 7,876 MRI scans, were included. Thickness of the right hemisphere, and particularly the right caudal anterior cingulate, right medial orbitofrontal, and left lateral occipital cortex, presented no differences or even thicker regional cortices in women compared to men in gender-equal countries, reversing to thinner cortices in countries with greater gender inequality. These results point to the potentially hazardous effect of gender inequality on women's brains and provide initial evidence for neuroscience-informed policies for gender equality

Telomere length and CCL11 levels are associated with gray matter volume and episodic memory performance in Schizophrenia: Evidence of pathological accelerated aging

Schizophrenia (SZ) is associated with increased somatic morbidity and mortality, in addition to cognitive impairments similar to those seen in normal aging, which may suggest that pathological accelerated aging occurs in SZ. Therefore, we aim to evaluate the relationships of age, telomere length (TL), and CCL11 (aging and inflammatory biomarkers, respectively), gray matter (GM) volume and episodic memory performance in individuals with SZ compared to healthy controls (HC). One hundred twelve participants (48 SZ and 64 HC) underwent clinical and memory assessments, structural MRI, and had their peripheral blood drawn for biomarkers analysis. Comparisons of group means and correlations were performed. Participants with SZ had decreased TL and GM volume, increased CCL11, and worse memory performance compared to HC. In SZ, shorter TL was related to increased CCL11, and both biomarkers were related to reduced GM volume, all of which were related to worse memory performance. Older age was only associated with reduced GM, but longer duration of illness was related with all the aforementioned variables. Younger age of disease onset was associated with increased CCL11 levels and worse memory performance. In HC, there were no significant correlations except between memory and GM. Our results are consistent with the hypothesis of accelerated aging in SZ. These results may indicate that it is not age itself, but the impact of the disease associated with a pathological accelerated aging that leads to impaired outcomes in SZ

Imaging social and environmental factors as modulators of brain dysfunction: time to focus on developing, non-Western societies

Social and environmental factors are known risk factors and modulators of mental health disorders. We here conducted a nonsystematic review of the neuroimaging literature studying the effects of poverty, urbanicity, and community violence, highlighting the opportunities of studying non-Western developing societies such as those in Latin America. Social and environmental factors in these communities are widespread and have a large magnitude, as well as an unequal distribution, providing a good opportunity for their characterization. Studying the effect of poverty in these settings could help to explore the brain effect of economic improvements, disentangle the effect of absolute and relative poverty, and characterize the modulating impact of poverty on the underlying biology of mental health disorders. Exploring urbanicity effects in highly unequal cities could help identify the specific factors that modulate this effect as well as examine a possible dose–response effect by studying megacities. Studying brain changes in those living among violence, which is particularly high in places such as Latin America, could help to characterize the interplay between brain predisposition and exposure to violence. Furthermore, exploring the brain in an adverse environment should shed light on the mechanisms underlying resilience. We finally provide examples of two methodological approaches that could contribute to this field, namely a big cohort study in the developing world and a consortium-based meta-analytic approach, and argue about the potential translational value of this research on the development of effective social policies and successful personalized medicine in disadvantaged societies.Fil: Crossley, Nicolas A.. Pontificia Universidad Católica de Chile; ChileFil: Alliende, Luz Maria. Pontificia Universidad Católica de Chile; ChileFil: Ossandon, Tomas. Pontificia Universidad Católica de Chile; ChileFil: Castañeda, Carmen Paz. Instituto Psiquiátrico Dr. José Horwitz Barak; ChileFil: González Valderrama, Alfonso. Instituto Psiquiátrico Dr. José Horwitz Barak; Chile. Universidad Finis Terrae.; ChileFil: Undurraga, Juan. Universidad del Desarrollo; Chile. Instituto Psiquiátrico Dr. José Horwitz Barak; ChileFil: Castro, Mariana Nair. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Guinjoan, Salvador Martín. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Díaz Zuluaga, Ana M.. Universidad de Antioquia; ColombiaFil: Pineda-Zapata, Julián A.. Instituto de Alta Tecnología Médica; ColombiaFil: López-Jaramillo, Carlos. Hospital Universitario San Vicente Fundación; Colombia. Universidad de Antioquia; ColombiaFil: Reyes Madrigal, Francisco. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: León-Ortíz, Pablo. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: de la Fuente-Sandoval, Camilo. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Czepielewski, Leticia Sanguinetti. Hospital de Clinicas de Porto Alegre; BrasilFil: Gama, Clarissa S.. Hospital de Clinicas de Porto Alegre; BrasilFil: Zugman, Andre. Universidade Federal de Sao Paulo; BrasilFil: Gadelha, Ary. Universidade Federal de Sao Paulo; BrasilFil: Jackowski, Andrea. Universidade Federal de Sao Paulo; BrasilFil: Bressan, Rodrigo. Universidade Federal de Sao Paulo; Brasi

Structural brain abnormalities in schizophrenia in adverse environments:Examining the effect of poverty and violence in six Latin American cities

Summary Background 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- A nd middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.Fil: Crossley, Nicolas A.. Pontificia Universidad Católica de Chile; ChileFil: Zugman, Andre. Universidade Federal de Sao Paulo; BrasilFil: Reyes Madrigal, Francisco. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Czepielewski, Leticia S.. Universidade Federal do Rio Grande do Sul; BrasilFil: Castro, Mariana Nair. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Salud Mental; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia. Instituto de Neurociencias - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; ArgentinaFil: Diaz Zuluaga, Ana M.. Universidad de Antioquia; ColombiaFil: Pineda Zapata, Julian A.. No especifíca;Fil: Reckziegel, Ramiro. Universidade Federal do Rio Grande do Sul; BrasilFil: Gadelha, Ary. Universidade Federal de Sao Paulo; BrasilFil: Jackowski, Andrea. Universidade Federal de Sao Paulo; BrasilFil: Noto, Cristiano. Universidade Federal de Sao Paulo; BrasilFil: Alliende, Luz M.. Pontificia Universidad Católica de Chile; ChileFil: Iruretagoyena, Barbara. Pontificia Universidad Católica de Chile; ChileFil: Ossandon, Tomas. Pontificia Universidad Católica de Chile; ChileFil: Ramirez Mahaluf, Juan P.. Pontificia Universidad Católica de Chile; ChileFil: Castañeda, Carmen P.. Instituto Psiquiátrico Dr. José Horwitz Barak; ChileFil: Gonzalez Valderrama, Alfonso. Universidad Finis Terrae; ChileFil: Nachar, Ruben. Instituto Psiquiátrico Dr. José Horwitz Barak; ChileFil: León Ortiz, Pablo. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Undurraga, Juan. Universidad del Desarrollo; ChileFil: López Jaramillo, Carlos. Universidad de Antioquia; ColombiaFil: Guinjoan, Salvador Martín. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Salud Mental; Argentina. Fundación para la Lucha contra las Enfermedades Neurológicas de la Infancia. Instituto de Neurociencias - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Neurociencias; ArgentinaFil: Gama, Clarissa S.. Universidade Federal do Rio Grande do Sul; BrasilFil: De La Fuente Sandoval, Camilo. Instituto Nacional de Neurología y Neurocirugía; MéxicoFil: Bressan, Rodrigo A.. Universidade Federal de Sao Paulo; Brasi

The enduring gap in educational attainment in schizophrenia according to the last 50 years of published research: a meta-analysis

Background. Educational attainment is associated with well-being and health. Unfortunately, patients with schizophrenia achieve lower levels of education. Several effective interventions can ameliorate this. However, the magnitude of the education gap in schizophrenia and changes over time are unclear. Methods. We performed a systematic review and meta-analysis including all studies reporting on patients with schizophrenia and describing their years of education, with or without healthy controls. There were no other design constraints on studies. 22 reviewers participated in retrieving data from a search in PubMed and PsycINFO (January 1st, 1970, to November 24th, 2020). We estimated the birth date of participants from their mean age and publication date, and metaanalyzed these data, focusing on educational attainment, the education gap, and changes over time. The protocol was registered in PROSPERO (CRD42020220546). Outcomes. From 32,593 initial references, we included 3,321 studies reporting on 318,632 patients alongside 138,675 healthy controls (170,941 women and 275,821 men from studies describing gender; ethnicity was not collected). Patients educational attainment increased over time mirroring the controls.  However, patients achieved 19 months less than patients, and this remained unchanged throughout the decades. Studies were biased to include more educated patients and controls than their respective larger population, but results were unchanged in studies with groups with similar parental education. Interpretation. Patients with schizophrenia have faced persistent inequality in educational attainment in the last century, despite advances in psychosocial and pharmacological treatment. Reducing this gap should become a priority to improve their functional outcomes