Background: Personality disorders (PDs) are estimated to occur in 6.8% of South Africans and in 45% to 80% of clinical populations. Mental health practitioners often harbour negative attitudes and lack confidence in working with such patients.
View Article and Find Full Text PDFMultivariate techniques better fit the anatomy of complex neuropsychiatric disorders which are characterized not by alterations in a single region, but rather by variations across distributed brain networks. Here, we used principal component analysis (PCA) to identify patterns of covariance across brain regions and relate them to clinical and demographic variables in a large generalizable dataset of individuals with bipolar disorders and controls. We then compared performance of PCA and clustering on identical sample to identify which methodology was better in capturing links between brain and clinical measures.
View Article and Find Full Text PDFBackground: Patients with multi-episode bipolar and psychotic disorders have a high prevalence of substance use disorders, with negative consequences. A brief, easily administered screening test such as the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) is needed to identify those at risk in order to intervene appropriately. However, the ASSIST has not yet been validated in this population.
View Article and Find Full Text PDFConverging evidence suggests that schizophrenia (SZ) with primary, enduring negative symptoms (i.e., Deficit SZ (DSZ)) represents a distinct entity within the SZ spectrum while the neurobiological underpinnings remain undetermined.
View Article and Find Full Text PDFBackground: Obesity is highly prevalent and disabling, especially in individuals with severe mental illness including bipolar disorders (BD). The brain is a target organ for both obesity and BD. Yet, we do not understand how cortical brain alterations in BD and obesity interact.
View Article and Find Full Text PDFAims: Rates of obesity have reached epidemic proportions, especially among people with psychiatric disorders. While the effects of obesity on the brain are of major interest in medicine, they remain markedly under-researched in psychiatry.
Methods: We obtained body mass index (BMI) and magnetic resonance imaging-derived regional cortical thickness, surface area from 836 bipolar disorders (BD) and 1600 control individuals from 14 sites within the ENIGMA-BD Working Group.
Schizophrenia is associated with widespread alterations in subcortical brain structure. While analytic methods have enabled more detailed morphometric characterization, findings are often equivocal. In this meta-analysis, we employed the harmonized ENIGMA shape analysis protocols to collaboratively investigate subcortical brain structure shape differences between individuals with schizophrenia and healthy control participants.
View Article and Find Full Text PDFBackground: The aim of the current study was to explore the effect of gender, age at onset, and duration on the long-term course of schizophrenia.
Methods: Twenty-nine centers from 25 countries representing all continents participated in the study that included 2358 patients aged 37.21 ± 11.
Individuals with bipolar disorders (BD) frequently suffer from obesity, which is often associated with neurostructural alterations. Yet, the effects of obesity on brain structure in BD are under-researched. We obtained MRI-derived brain subcortical volumes and body mass index (BMI) from 1134 BD and 1601 control individuals from 17 independent research sites within the ENIGMA-BD Working Group.
View Article and Find Full Text PDFDelineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown that robust estimates of the association between age and brain morphometry require large-scale studies. In response, we used cross-sectional data from 17,075 individuals aged 3-90 years from the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) Consortium to infer age-related changes in cortical thickness.
View Article and Find Full Text PDFAge has a major effect on brain volume. However, the normative studies available are constrained by small sample sizes, restricted age coverage and significant methodological variability. These limitations introduce inconsistencies and may obscure or distort the lifespan trajectories of brain morphometry.
View Article and Find Full Text PDFThe hippocampus consists of anatomically and functionally distinct subfields that may be differentially involved in the pathophysiology of bipolar disorder (BD). Here we, the Enhancing NeuroImaging Genetics through Meta-Analysis Bipolar Disorder workinggroup, study hippocampal subfield volumetry in BD. T1-weighted magnetic resonance imaging scans from 4,698 individuals (BD = 1,472, healthy controls [HC] = 3,226) from 23 sites worldwide were processed with FreeSurfer.
View Article and Find Full Text PDFFor many traits, males show greater variability than females, with possible implications for understanding sex differences in health and disease. Here, the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) Consortium presents the largest-ever mega-analysis of sex differences in variability of brain structure, based on international data spanning nine decades of life. Subcortical volumes, cortical surface area and cortical thickness were assessed in MRI data of 16,683 healthy individuals 1-90 years old (47% females).
View Article and Find Full Text PDFJAMA Psychiatry
January 2021
Background: Substance use disorders (SUDs) occur frequently in patients with psychotic disorders and have been associated with various demographic and clinical correlates. There is an absence of research on the prevalence and clinical correlates of SUDs in psychotic disorders in low-and-middle-income countries (LMICs).
Aim: We aimed to determine the prevalence and correlates of SUDs in psychotic disorders.
Soc Psychiatry Psychiatr Epidemiol
April 2021
Purpose: To determine the prevalence of substance use disorders (SUDs) in patients with schizophrenia in a sample from South Africa and compare the clinical and demographic correlates in those with and without co-occurring SUDs.
Methods: Patients with schizophrenia were interviewed using the Xhosa version SCID-I for DSM-IV. We used logistic regression to determine the predictors of SUDs.
Major depressive disorder (MDD) is associated with an increased risk of brain atrophy, aging-related diseases, and mortality. We examined potential advanced brain aging in adult MDD patients, and whether this process is associated with clinical characteristics in a large multicenter international dataset. We performed a mega-analysis by pooling brain measures derived from T1-weighted MRI scans from 19 samples worldwide.
View Article and Find Full Text PDFBackground: The aim of the current study was to explore the changing interrelationships among clinical variables through the stages of schizophrenia in order to assemble a comprehensive and meaningful disease model.
Methods: Twenty-nine centers from 25 countries participated and included 2358 patients aged 37.21 ± 11.
Extrapyramidal side-effects (EPSE) are frequent in patients treated with antipsychotics and comorbid substance use disorders (SUDs). Methamphetamine has been shown to act as a dopaminergic neurotoxin. We aimed to determine whether EPSE occur more often in patients with psychotic disorders and co-occurring methamphetamine (MA) use disorders, and we examined the relationship between MA use, antipsychotic type, dose and EPSE.
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