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.

Age of onset of obsessive-compulsive disorder differentially affects white matter microstructure.

Previous diffusion MRI studies have reported mixed findings on white matter microstructure alterations in obsessive-compulsive disorder (OCD), likely due to variation in demographic and clinical characteristics, scanning methods, and underpowered samples. The OCD global study was created across five international sites to overcome these challenges by harmonizing data collection to identify consistent brain signatures of OCD that are reproducible and generalizable. Single-shell diffusion measures (e.g., fractional anisotropy), multi-shell Neurite Orientation Dispersion and Density Imaging (NODDI) and fixel-based measures, were extracted from skeletonized white matter tracts in 260 medication-free adults with OCD and 252 healthy controls. We additionally performed structural connectome analysis. We compared cases with controls and cases with early (<18) versus late (18+) OCD onset using mixed-model and Bayesian multilevel analysis. Compared with healthy controls, adult OCD individuals showed higher fiber density in the sagittal stratum (B[SE] = 0.10[0.05], P = 0.04) and credible evidence for higher fiber density in several other tracts. When comparing early (n = 145) and late-onset (n = 114) cases, converging evidence showed lower integrity of the posterior thalamic radiation -particularly radial diffusivity (B[SE] = 0.28[0.12], P = 0.03)-and lower global efficiency of the structural connectome (B[SE] = 15.3[6.6], P = 0.03) in late-onset cases. Post-hoc analyses indicated divergent direction of effects of the two OCD groups compared to healthy controls. Age of OCD onset differentially affects the integrity of thalamo-parietal/occipital tracts and the efficiency of the structural brain network. These results lend further support for the role of the thalamus and its afferent fibers and visual attentional processes in the pathophysiology of OCD.

The functional connectome in obsessive-compulsive disorder: resting-state mega-analysis and machine learning classification for the ENIGMA-OCD consortium.

Current knowledge about functional connectivity in obsessive-compulsive disorder (OCD) is based on small-scale studies, limiting the generalizability of results. Moreover, the majority of studies have focused only on predefined regions or functional networks rather than connectivity throughout the entire brain. Here, we investigated differences in resting-state functional connectivity between OCD patients and healthy controls (HC) using mega-analysis of data from 1024 OCD patients and 1028 HC from 28 independent samples of the ENIGMA-OCD consortium. We assessed group differences in whole-brain functional connectivity at both the regional and network level, and investigated whether functional connectivity could serve as biomarker to identify patient status at the individual level using machine learning analysis. The mega-analyses revealed widespread abnormalities in functional connectivity in OCD, with global hypo-connectivity (Cohen's d: -0.27 to -0.13) and few hyper-connections, mainly with the thalamus (Cohen's d: 0.19 to 0.22). Most hypo-connections were located within the sensorimotor network and no fronto-striatal abnormalities were found. Overall, classification performances were poor, with area-under-the-receiver-operating-characteristic curve (AUC) scores ranging between 0.567 and 0.673, with better classification for medicated (AUC = 0.702) than unmedicated (AUC = 0.608) patients versus healthy controls. These findings provide partial support for existing pathophysiological models of OCD and highlight the important role of the sensorimotor network in OCD. However, resting-state connectivity does not so far provide an accurate biomarker for identifying patients at the individual level.

Structured clinical interview for diagnosing obsessive-compulsive spectrum disorders.

BACKGROUND: There are several established structured diagnostic interviews that cover common mental disorders seen in general psychiatry clinics. The administration of more focused diagnostic interviews may be useful in specialty clinics, such as OCD clinics. A semi-structured clinician-administered interview for obsessive-compulsive spectrum disorders (SCID-OCSD) was developed and adapted for DSM-5/ICD-11 obsessive-compulsive and related disorders as well as other putative obsessive-compulsive spectrum conditions. OBJECTIVE: To introduce a semi-structured diagnostic interview for in-depth assessment of obsessive-compulsive spectrum disorders (OCSDs), and to report on its implementation in adults with primary OCD attending an OCD-specialized unit. METHODS: Patients with primary OCD were interviewed using the SCID-OCSD. The SCID-OCSD assesses disorders drawn from several diagnostic categories that share some core features of obsessive-compulsive phenomenology and that are often comorbid in OCD (e.g., obsessive-compulsive related disorders, impulse-control disorders, and a spectrum of compulsive-impulsive conditions such as tics, eating disorders, non-suicidal self-injury, and behavioral addictions. Participants had to be at least moderately symptomatic on the Yale-Brown Obsessive-Compulsive Severity scale (YBOCS, i.e., a total score ≥ 14) to be included in the current study. RESULTS: One hundred and one adult patients with current OCD (n = 101, 37 men and 64 women), took part in the study. Forty-two participants (n = 42) had OCD and one or more current or past comorbid OCSDs, with excoriation (skin-picking) disorder (n = 16) and body dysmorphic disorder (n = 14) being the most common. Nine (n = 9) participants reported a history of non-suicidal self-injury, and 6 participants reported a history of comorbid tics. CONCLUSIONS: In OCD clinics, the SCID-OCSD may help diagnose the full range of putative OCSDs, and so facilitate treatment planning and research on these conditions.

Patient Perceptions of Illness Causes and Treatment Preferences for Obsessive-Compulsive Disorder: A Mixed-Methods Study.

Obsessive-compulsive disorder (OCD) is a condition with high patient morbidity and mortality. Research shows that eliciting patient explanations about illness causes and treatment preferences promotes cross-cultural work and engagement in health services. These topics are in the Cultural Formulation Interview (CFI), a semi-structured interview first published in DSM-5 that applies anthropological approaches within mental health services to promote person-centered care. This study focuses on the New York City site of an international multi-site study that used qualitative-quantitative mixed methods to: (1) analyze CFI transcripts with 55 adults with OCD to explore perceived illness causes and treatment preferences, and (2) explore whether past treatment experiences are related to perceptions about causes of current symptoms. The most commonly named causes were circumstantial stressors (n = 16), genetics (n = 12), personal psychological traits (n = 9), an interaction between circumstantial stressors and participants' brains (n = 6), and a non-specific brain problem (n = 6). The most common treatment preferences were psychotherapy (n = 42), anything (n = 4), nothing (n = 4), and medications (n = 2). Those with a prior medication history had twice the odds of reporting a biological cause, though this was not a statistically significant difference. Our findings suggest that providers should ask patients about illness causes and treatment preferences to guide treatment choice.

Cerebellar Volume and Disease Staging in Parkinson's Disease: An ENIGMA-PD Study.

BACKGROUND: Increasing evidence points to a pathophysiological role for the cerebellum in Parkinson's disease (PD). However, regional cerebellar changes associated with motor and non-motor functioning remain to be elucidated. OBJECTIVE: To quantify cross-sectional regional cerebellar lobule volumes using three dimensional T1-weighted anatomical brain magnetic resonance imaging from the global ENIGMA-PD working group. METHODS: Cerebellar parcellation was performed using a deep learning-based approach from 2487 people with PD and 1212 age and sex-matched controls across 22 sites. Linear mixed effects models compared total and regional cerebellar volume in people with PD at each Hoehn and Yahr (HY) disease stage, to an age- and sex- matched control group. Associations with motor symptom severity and Montreal Cognitive Assessment scores were investigated. RESULTS: Overall, people with PD had a regionally smaller posterior lobe (dmax = -0.15). HY stage-specific analyses revealed a larger anterior lobule V bilaterally (dmax = 0.28) in people with PD in HY stage 1 compared to controls. In contrast, smaller bilateral lobule VII volume in the posterior lobe was observed in HY stages 3, 4, and 5 (dmax = -0.76), which was incrementally lower with higher disease stage. Within PD, cognitively impaired individuals had lower total cerebellar volume compared to cognitively normal individuals (d = -0.17). CONCLUSIONS: We provide evidence of a dissociation between anterior "motor" lobe and posterior "non-motor" lobe cerebellar regions in PD. Whereas less severe stages of the disease are associated with larger motor lobe regions, more severe stages of the disease are marked by smaller non-motor regions. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Neurobiology of subtypes of trichotillomania and skin picking disorder.

BACKGROUND: Trichotillomania (TTM) and skin picking disorder (SPD) are common and often debilitating mental health conditions, grouped under the umbrella term of body-focused repetitive behaviors (BFRBs). Recent clinical subtyping found that there were three distinct subtypes of TTM and two of SPD. Whether these clinical subtypes map on to any unique neurobiological underpinnings, however, remains unknown. METHODS: Two hundred and fifty one adults [193 with a BFRB (85.5% [n = 165] female) and 58 healthy controls (77.6% [n = 45] female)] were recruited from the community for a multicenter between-group comparison using structural neuroimaging. Differences in whole brain structure were compared across the subtypes of BFRBs, controlling for age, sex, scanning site, and intracranial volume. RESULTS: When the subtypes of TTM were compared, low awareness hair pullers demonstrated increased cortical volume in the lateral occipital lobe relative to controls and sensory sensitive pullers. In addition, impulsive/perfectionist hair pullers showed relative decreased volume near the lingual gyrus of the inferior occipital-parietal lobe compared with controls. CONCLUSIONS: These data indicate that the anatomical substrates of particular forms of BFRBs are dissociable, which may have implications for understanding clinical presentations and treatment response.

Internet severity and activities addiction questionnaire (ISAAQ): Psychometrics of item response theory and clustering of online activities.

BACKGROUND: Problematic usage of the internet (PUI) is an umbrella term, referring to a variety of maladaptive online behaviors linked to functional impairment. There is ongoing need for the development of instruments capturing not only PUI severity, but also the online activity types. The Internet Severity and Activities Questionnaire (ISAAQ), previously developed to address this need, required further refinement and validation. METHODS: Cross-sectional data was gathered in two separate samples (South Africa n = 3275, USA-UK n = 943) using the Internet Severity and Activities Addiction Questionnaire (ISAAQ). Item Response Theory (IRT) was used to examine the properties of the scale (Part A of the ISAAQ) and differential item functioning against demographic parameters. The severity scale of the ISAAQ was optimized by eliminating the poorest performing items using an iterative approach and examining validity metrics. Cluster analyses was used to examine internet activities and commonalities across samples (Part B of the ISAAQ). RESULTS: Optimization of ISAAQ using IRT yielded a refined 10-item version (ISAAQ-10), with less differential item functioning and a robust unidimensional factor structure. The ISAAQ-10 severity score correlated strongly with established measures of internet addiction (Compulsive Internet Use Scale [Person's r = 0.86] and the Internet Addiction Test-10 [r = 0.75]). Combined with gaming activity score it correlated moderately strongly with the established Internet Gaming Disorder Test (r = 0.65). Exploratory cluster analyses in both samples identified two groups, one of "low-PUI" [98.1-98.5%], and one of "high-PUI" [1.5-1.9%]. Multiple facets of internet activity appeared elevated in the high-PUI cluster. DISCUSSION: The ISAAQ-10 supersedes the earlier longer version of the ISAAQ, and provides a useful, psychometrically robust measure of PUI severity (Part A), and captures the extent of engagement in a wide gamut of online specific internet activities (Part B). ISAAQ-10 constitutes a valuable objective measurement tool for future studies.

Conceptualising compulsivity through network analysis: A two-sample study.

Compulsivity is a transdiagnostic construct crucial to understanding multiple psychiatric conditions and problematic repetitive behaviours. Despite being identified as a clinical- and research-relevant construct, there are limited insights into the internal conceptual structure of compulsivity. To provide a more nuanced understanding of compulsivity, the current study estimated the structure of compulsivity (indexed using the previously validated Cambridge-Chicago Compulsivity Trait Scale, CHI-T) among two large-scale and geographically distinct samples using the network estimation method. The samples consisted of a United Kingdom cohort (n = 122,346, 51.4% female, Mean age = 43.7, SD = 16.5, range = 9-86 years) and a South Africa cohort (n = 2674, 65.6% female, Mean age = 24.6, SD = 8.6, range = 18-65 years). Network community analysis demonstrated that compulsivity was constituted of three interrelated dimensions, namely: perfectionism, cognitive rigidity and reward drive. Further, 'Completion leads to soothing' and 'Difficulty moving from task to task' were identified as core (central nodes) to compulsivity. The dimensional structure and central nodes of compulsivity networks were consistent across the two samples. These findings facilitate the conceptualisation and measurement of compulsivity and may contribute to the early detection and treatment of compulsivity-related disorders.

A cross-national validation of the Internet Severity and Activities Addiction Questionnaire (ISAAQ).

Problematic usage of the internet (PUI) is of increasing concern in a digitalized world. While several screening tools have been developed to assess PUI, few have had their psychometric properties evaluated, and existing scales are also not typically designed to quantify both the severity of PUI and the nature of diverse problematic online activities. The Internet Severity and Activities Addiction Questionnaire (ISAAQ), consisting of a severity scale (ISAAQ Part A) and an online activities scale (ISAAQ part B) was previously developed to address these limitations. This study undertook psychometric validation of ISAAQ Part A using data from three countries. The optimal one-factor structure of ISAAQ Part A was determined in a large dataset from South Africa, then validated against datasets from the United Kingdom and United States. The scale had high Cronbach's alpha (≥0.9 in each country). A working operational cut-off point was determined to distinguish between those with some degree of problematic use and those without (ISAAQ Part A), and insight was given into the types of potentially problematic activities that may encompass PUI (ISAAQ Part B).

Psychometric properties of the Alcohol Use Disorders Identification Test (AUDIT) across cross-cultural subgroups, genders, and sexual orientations: Findings from the International Sex Survey (ISS).

INTRODUCTION: Despite being a widely used screening questionnaire, there is no consensus on the most appropriate measurement model for the Alcohol Use Disorders Identification Test (AUDIT). Furthermore, there have been limited studies on its measurement invariance across cross-cultural subgroups, genders, and sexual orientations. AIMS: The present study aimed to examine the fit of different measurement models for the AUDIT and its measurement invariance across a wide range of subgroups by country, language, gender, and sexual orientation. METHODS: Responses concerning past-year alcohol use from the participants of the cross-sectional International Sex Survey were considered (N = 62,943; Mage: 32.73; SD = 12.59). Confirmatory factor analysis, as well as measurement invariance tests were performed for 21 countries, 14 languages, three genders, and four sexual-orientation subgroups that met the minimum sample size requirement for inclusion in these analyses. RESULTS: A two-factor model with factors describing 'alcohol use' (items 1-3) and 'alcohol problems' (items 4-10) showed the best model fit across countries, languages, genders, and sexual orientations. For the former two, scalar and latent mean levels of invariance were reached considering different criteria. For gender and sexual orientation, a latent mean level of invariance was reached. CONCLUSIONS: In line with the two-factor model, the calculation of separate alcohol-use and alcohol-problem scores is recommended when using the AUDIT. The high levels of measurement invariance achieved for the AUDIT support its use in cross-cultural research, capable also of meaningful comparisons among genders and sexual orientations.

An overview of the first 5 years of the ENIGMA obsessive-compulsive disorder working group: The power of worldwide collaboration.

Neuroimaging has played an important part in advancing our understanding of the neurobiology of obsessive-compulsive disorder (OCD). At the same time, neuroimaging studies of OCD have had notable limitations, including reliance on relatively small samples. International collaborative efforts to increase statistical power by combining samples from across sites have been bolstered by the ENIGMA consortium; this provides specific technical expertise for conducting multi-site analyses, as well as access to a collaborative community of neuroimaging scientists. In this article, we outline the background to, development of, and initial findings from ENIGMA's OCD working group, which currently consists of 47 samples from 34 institutes in 15 countries on 5 continents, with a total sample of 2,323 OCD patients and 2,325 healthy controls. Initial work has focused on studies of cortical thickness and subcortical volumes, structural connectivity, and brain lateralization in children, adolescents and adults with OCD, also including the study on the commonalities and distinctions across different neurodevelopment disorders. Additional work is ongoing, employing machine learning techniques. Findings to date have contributed to the development of neurobiological models of OCD, have provided an important model of global scientific collaboration, and have had a number of clinical implications. Importantly, our work has shed new light on questions about whether structural and functional alterations found in OCD reflect neurodevelopmental changes, effects of the disease process, or medication impacts. We conclude with a summary of ongoing work by ENIGMA-OCD, and a consideration of future directions for neuroimaging research on OCD within and beyond ENIGMA.

Toward a neurocircuit-based taxonomy to guide treatment of obsessive-compulsive disorder.

An important challenge in mental health research is to translate findings from cognitive neuroscience and neuroimaging research into effective treatments that target the neurobiological alterations involved in psychiatric symptoms. To address this challenge, in this review we propose a heuristic neurocircuit-based taxonomy to guide the treatment of obsessive-compulsive disorder (OCD). We do this by integrating information from several sources. First, we provide case vignettes in which patients with OCD describe their symptoms and discuss different clinical profiles in the phenotypic expression of the condition. Second, we link variations in these clinical profiles to underlying neurocircuit dysfunctions, drawing on findings from neuropsychological and neuroimaging studies in OCD. Third, we consider behavioral, pharmacological, and neuromodulatory treatments that could target those specific neurocircuit dysfunctions. Finally, we suggest methods of testing this neurocircuit-based taxonomy as well as important limitations to this approach that should be considered in future research.

The neurobiology of obsessive-compulsive personality disorder: a systematic review.

BACKGROUND: A number of recent investigations have focused on the neurobiology of obsessive-compulsive personality disorder (OCPD). However, there have been few reviews of this literature with no detailed model proposed. We therefore undertook a systematic review of these investigations, aiming to map the available evidence and investigate whether it is possible to formulate a detailed model of the neurobiology of OCPD. METHODS: OCPD can be considered from both categorical and dimensional perspectives. An electronic search was therefore conducted using terms that would address not only OCPD as a category, but also related constructs, such as perfectionism, that would capture research on neuropsychology, neuroimaging, neurochemistry, and neurogenetics. RESULTS: A total of 1059 articles were retrieved, with 87 ultimately selected for abstract screening, resulting in a final selection of 49 articles focusing on neurobiological investigations relevant to OCPD. Impaired executive function and cognitive inflexibility are common neuropsychological traits in this condition, and suggest that obsessive-compulsive disorder (OCD) and OCPD may lie on a continuum. However, neuroimaging studies in OCPD indicate the involvement of specific neurocircuitry, including the precuneus and amygdala, and so suggest that OCD and OCPD may have important differences. Although OCPD has a heritable component, we found no well-powered genetic studies of OCPD. CONCLUSION: Although knowledge in this area has advanced, there are insufficient data on which to base a comprehensive model of the neurobiology of OCPD. Given the clinical importance of OCPD, further work to understand the mechanisms that underpin this condition is warranted.

Pain perception and physiological correlates in body-focused repetitive behavior disorders.

BACKGROUND: Behaviors typical of body-focused repetitive behavior disorders such as trichotillomania (TTM) and skin-picking disorder (SPD) are often associated with pleasure or relief, and with little or no physical pain, suggesting aberrant pain perception. Conclusive evidence about pain perception and correlates in these conditions is, however, lacking. METHODS: A multisite international study examined pain perception and its physiological correlates in adults with TTM (n = 31), SPD (n = 24), and healthy controls (HCs; n = 26). The cold pressor test was administered, and measurements of pain perception and cardiovascular parameters were taken every 15 seconds. Pain perception, latency to pain tolerance, cardiovascular parameters and associations with illness severity, and comorbid depression, as well as interaction effects (group × time interval), were investigated across groups. RESULTS: There were no group differences in pain ratings over time (P = .8) or latency to pain tolerance (P = .8). Illness severity was not associated with pain ratings (all P > .05). In terms of diastolic blood pressure (DBP), the main effect of group was statistically significant (P = .01), with post hoc analyses indicating higher mean DBP in TTM (95% confidence intervals [CI], 84.0-93.5) compared to SPD (95% CI, 73.5-84.2; P = .01), and HCs (95% CI, 75.6-86.0; P = .03). Pain perception did not differ between those with and those without depression (TTM: P = .2, SPD: P = .4). CONCLUSION: The study findings were mostly negative suggesting that general pain perception aberration is not involved in TTM and SPD. Other underlying drivers of hair-pulling and skin-picking behavior (eg, abnormal reward processing) should be investigated.

The role of gender in a large international OCD sample: A Report from the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) Network.

INTRODUCTION: Obsessive-compulsive disorder (OCD) is characterized by a range of phenotypic expressions. Gender may be a relevant factor in mediating the disorder's heterogeneity. The aim of the present report was to explore a large multisite clinical sample of OCD patients, hypothesizing existing demographic, geographical and clinical differences between male and female patients with OCD. METHODS: Socio-demographic and clinical variables of 491 adult OCD outpatients recruited in the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) network were investigated with a retrospective analysis on a previously gathered set of data from eleven countries worldwide. Patients were assessed through structured clinical interviews, the Yale- Brown Obsessive-Compulsive Scale (Y-BOCS), the Montgomery-Asberg Depression Rating Scale (MADRS) and the Self-rating Depression Scale (SDS). RESULTS: Among females, adult onset (>18 years old) was significantly over-represented (67% vs. 33%, p < 0.005), and females showed a significantly older age at illness onset compared with males (20.85 ± 10.76 vs. 17.71 ± 8.96 years, p < 0.005). Females also had a significantly lower education level than males (13.09 ± 4.02 vs. 13.98 ± 3.85 years; p < 0.05), a significantly higher rate of being married (50.8% vs. 33.5%; p < 0.001) and a higher rate of living with a partner (47.5% vs. 37.6%; p < 0.001) than males. Nonetheless, no significant gender differences emerged in terms of the severity of OCD symptoms nor in the severity of comorbid depressive symptoms. No predictive effect of gender was found for Y-BOCS, MADRS and SDS severity. DISCUSSION/CONCLUSIONS: Our findings showed significant differences between genders in OCD. A sexually dimorphic pattern of genetic susceptibility may have a crucial role to OCD clinical heterogeneity, potentially requiring different specific therapeutic strategies. Further research is warranted to validate gender as an important determinant of the heterogeneity in OCD.

Advances in problematic usage of the internet research - A narrative review by experts from the European network for problematic usage of the internet.

Global concern about problematic usage of the internet (PUI), and its public health and societal costs, continues to grow, sharpened in focus under the privations of the COVID-19 pandemic. This narrative review reports the expert opinions of members of the largest international network of researchers on PUI in the framework of the European Cooperation in Science and Technology (COST) Action (CA 16207), on the scientific progress made and the critical knowledge gaps remaining to be filled as the term of the Action reaches its conclusion. A key advance has been achieving consensus on the clinical definition of various forms of PUI. Based on the overarching public health principles of protecting individuals and the public from harm and promoting the highest attainable standard of health, the World Health Organisation has introduced several new structured diagnoses into the ICD-11, including gambling disorder, gaming disorder, compulsive sexual behaviour disorder, and other unspecified or specified disorders due to addictive behaviours, alongside naming online activity as a diagnostic specifier. These definitions provide for the first time a sound platform for developing systematic networked research into various forms of PUI at global scale. Progress has also been made in areas such as refining and simplifying some of the available assessment instruments, clarifying the underpinning brain-based and social determinants, and building more empirically based etiological models, as a basis for therapeutic intervention, alongside public engagement initiatives. However, important gaps in our knowledge remain to be tackled. Principal among these include a better understanding of the course and evolution of the PUI-related problems, across different age groups, genders and other specific vulnerable groups, reliable methods for early identification of individuals at risk (before PUI becomes disordered), efficacious preventative and therapeutic interventions and ethical health and social policy changes that adequately safeguard human digital rights. The paper concludes with recommendations for achievable research goals, based on longitudinal analysis of a large multinational cohort co-designed with public stakeholders.

Epidemiology of non-fatal suicidal behavior among first-year university students in South Africa.

Supplemental data for this article can be accessed on the publisher's website.We used a cross-sectional web-based survey and discrete-time survival analysis with person-year as unit of analysis and retrospective age-of-onset reports to estimate prevalence and predictors of suicidal ideation, plan, and attempt, and transitions from ideation to plan and attempt among South African university students (n = 1402). The lifetime prevalence of ideation, plan, and attempt were 46.4% (n = 650), 26.5% (n = 372), and 8.6% (n = 120), respectively. Multiple temporally primary mental disorders predicted subsequent onset of suicidality and transitions from ideation to plan and attempt. Results highlight the need for campus-based suicide prevention in South Africa, vulnerability of historically disadvantaged students, and the importance of promoting mental health in suicide prevention.

Clinical Characteristics of Youth with Trichotillomania (Hair-Pulling Disorder) and Excoriation (Skin-Picking) Disorder.

Body-focused repetitive disorders (BFRBDs) are understudied in youth and understanding of their underlying mechanisms is limited. This study evaluated BFRBD clinical characteristics, and two factors commonly implicated in their maintenance - emotion regulation and impulsivity - in 53 youth aged 11 to 17 years: 33 with BFRBDs and 20 controls. Evaluators administered psychiatric diagnostic interviews. Participants rated BFRBD severity, negative affect, quality of life, family functioning, emotion regulation, distress tolerance, and impulsivity. Youth with BFRBDs showed poorer distress tolerance and quality of life, and higher impulsivity and negative affect than controls, with no differences in family impairment. BFRBD distress/impairment, but not BFRBD severity, correlated with anxiety and depression, and poorer distress tolerance. Findings suggest youth with BFRBDs show clinical patterns aligning with prior research; highlight the role of distress tolerance in child BFRBDs; and suggest the utility of acceptance and mindfulness-based therapies for unpleasant emotions in BFRBDs. Continued research should evaluate factors underlying BFRBDs in youth.

Brain structural covariance networks in obsessive-compulsive disorder: a graph analysis from the ENIGMA Consortium.

Brain structural covariance networks reflect covariation in morphology of different brain areas and are thought to reflect common trajectories in brain development and maturation. Large-scale investigation of structural covariance networks in obsessive-compulsive disorder (OCD) may provide clues to the pathophysiology of this neurodevelopmental disorder. Using T1-weighted MRI scans acquired from 1616 individuals with OCD and 1463 healthy controls across 37 datasets participating in the ENIGMA-OCD Working Group, we calculated intra-individual brain structural covariance networks (using the bilaterally-averaged values of 33 cortical surface areas, 33 cortical thickness values, and six subcortical volumes), in which edge weights were proportional to the similarity between two brain morphological features in terms of deviation from healthy controls (i.e. z-score transformed). Global networks were characterized using measures of network segregation (clustering and modularity), network integration (global efficiency), and their balance (small-worldness), and their community membership was assessed. Hub profiling of regional networks was undertaken using measures of betweenness, closeness, and eigenvector centrality. Individually calculated network measures were integrated across the 37 datasets using a meta-analytical approach. These network measures were summated across the network density range of K = 0.10-0.25 per participant, and were integrated across the 37 datasets using a meta-analytical approach. Compared with healthy controls, at a global level, the structural covariance networks of OCD showed lower clustering (P < 0.0001), lower modularity (P < 0.0001), and lower small-worldness (P = 0.017). Detection of community membership emphasized lower network segregation in OCD compared to healthy controls. At the regional level, there were lower (rank-transformed) centrality values in OCD for volume of caudate nucleus and thalamus, and surface area of paracentral cortex, indicative of altered distribution of brain hubs. Centrality of cingulate and orbito-frontal as well as other brain areas was associated with OCD illness duration, suggesting greater involvement of these brain areas with illness chronicity. In summary, the findings of this study, the largest brain structural covariance study of OCD to date, point to a less segregated organization of structural covariance networks in OCD, and reorganization of brain hubs. The segregation findings suggest a possible signature of altered brain morphometry in OCD, while the hub findings point to OCD-related alterations in trajectories of brain development and maturation, particularly in cingulate and orbitofrontal regions.