Research Articles (Psychiatry)
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- ItemBrain ageing in schizophrenia : evidence from 26 international cohorts via the ENIGMA Schizophrenia consortium(Nature, 2022-12-09) Constantinides, Constantinos; Han, Laura K. M.; Alloza, Clara; Antonucci, Linda Antonella; Arango, Celso; Ayesa-Arriola, Rosa; Banaj, Nerisaq; Bertolino, Alessandro; Borgwardt, Stefan; Bruggemann, Jason; Bustillo, Juan; Bykhovski, Oleg; Calhoun, Vince; Catts, Stanley; Chung, Young-Chul; Crespo-Facorro, Benedicto; Diaz-Caneja, Covadonga M.; Donohoe, Gary; Du Plessis, Stefan; Edmond, Jesse; Ehrlich, Stefan; Emsley, Robin; Eyler, Lisa T.; Fuentes-Claramonte, Paola; Georgiadis, Foivos; Green, Melissa; Guerrero-Pedraza, Amalia; Ha, Minji; Hahn, Tim; Henskens, Frans A.; Holleran, Laurena; Homan, Stephanie; Jahanshad, Neda; Janssen, Joost; Ji, Ellen; Kaiser, Stefan; Kaleda, Vasily; Kim, Minah; Kim, Woo-Sung; Kirschner, Matthias; Kochunov, Peter; Kwak, Yoo Bin; Kwon, Jun Soo; Lebedeva, Irina; Liu, Jingyu; Mitchie, Patricia; Michielse, Stijn; Mothersill, David; Mowry, Bryan; Ortiz-Garcia de la Foz, Victor; Pantelis, Christos; Pergola, Giulio; Piras, Fabrizio; Pomarol-Clotet, Edith; Preda, Adrian; Quide, Yann; Rasser, Paul E.; Rootes-Murdy, Kelly; Salvador, Raymond; Sangiuliano, Marina; Sarro, Salvador; Schall, Ulrich; Schmidt, Andre; Scott, Rodney J.; Selvaggi, Pierluigi; Sim, Kang; Skoch, Antonin; Spalletta, Gianfranco; Spaniel, Filip; Thomopoulos, Sophia I.; Tomecek, David; Tomyshev, Alexander S.; Tordesillas-Gutierrez, Diana; Van Amelsvoort, Therese; Vazquez-Bourgon, Javier; Vecchio, Daniela; Voineskos, Aristotle; Weickert, Cynthia S.; Weickert, Thomas; Thompson, Paul M.; Schmaal, Lianne; Van Erp, Theo G. M.; Turner, Jessica; Cole, James H.; ENIGMA Schizophrenia Consortium; Dima, Danai; Walton, EstherSchizophrenia (SZ) is associated with an increased risk of life-long cognitive impairments, age-related chronic disease, and premature mortality. We investigated evidence for advanced brain ageing in adult SZ patients, and whether this was associated with clinical characteristics in a prospective meta-analytic study conducted by the ENIGMA Schizophrenia Working Group. The study included data from 26 cohorts worldwide, with a total of 2803 SZ patients (mean age 34.2 years; range 18–72 years; 67% male) and 2598 healthy controls (mean age 33.8 years, range 18–73 years, 55% male). Brain-predicted age was individually estimated using a model trained on independent data based on 68 measures of cortical thickness and surface area, 7 subcortical volumes, lateral ventricular volumes and total intracranial volume, all derived from T1-weighted brain magnetic resonance imaging (MRI) scans. Deviations from a healthy brain ageing trajectory were assessed by the difference between brain-predicted age and chronological age (brain-predicted age difference [brain-PAD]). On average, SZ patients showed a higher brain-PAD of +3.55 years (95% CI: 2.91, 4.19; I2 = 57.53%) compared to controls, after adjusting for age, sex and site (Cohen’s d = 0.48). Among SZ patients, brain-PAD was not associated with specific clinical characteristics (age of onset, duration of illness, symptom severity, or antipsychotic use and dose). This large-scale collaborative study suggests advanced structural brain ageing in SZ. Longitudinal studies of SZ and a range of mental and somatic health outcomes will help to further evaluate the clinical implications of increased brain-PAD and its ability to be influenced by interventions.
- ItemGlobal multi-center and multi-modal magnetic resonance imaging study of obsessive-compulsive disorder : harmonization and monitoring of protocols in healthy volunteers and phantoms(Wiley, 2022-08-15) Pouwels, Petra J. W.; Vriend, Chris; Liu, Feng; De Joode, Niels T.; Otaduy, Maria C. G.; Pastorello, Bruno; Robertson, Frances C.; Venkatasubramanian, Ganesan; Ipser, Jonathan; Lee, Seonjoo; Batistuzzo, Marcelo C.; Hoexter, Marcelo Q.; Lochner, Christine; Miguel, Euripedes C.; Narayanaswamy, Janardhanan C.; Rao, Rashmi; Reddy, Y. C. Janardhan; Shavitt, Roseli G.; Sheshachala, Karthik; Stein, Dan J.; Van Balkom, Anton J. L. M.; Wall, Melanie; Simpson, Helen Blair; Van den Heuvel, Odile A.Objectives: We describe the harmonized MRI acquisition and quality assessment of an ongoing global OCD study, with the aim to translate representative, well-powered neuroimaging findings in neuropsychiatric research to worldwide populations. Methods: We report on T1-weighted structural MRI, resting-state functional MRI, and multi-shell diffusion-weighted imaging of 140 healthy participants (28 per site), two traveling controls, and regular phantom scans. Results: Human image quality measures (IQMs) and outcome measures showed smaller within-site variation than between-site variation. Outcome measures were less variable than IQMs, especially for the traveling controls. Phantom IQMs were stable regarding geometry, SNR, and mean diffusivity, while fMRI fluctuation was more variable between sites. Conclusions: Variation in IQMs persists, even for an a priori harmonized data acquisition protocol, but after pre-processing they have less of an impact on the outcome measures. Continuous monitoring IQMs per site is valuable to detect potential artifacts and outliers. The inclusion of both cases and healthy participants at each site remains mandatory.
- ItemEffects of cannabidiol on vacuous chewing movements, plasma glucose and oxidative stress indices in rats administered high dose risperidone(Springer Nature, 2022-11-16) Kajero, Jaiyeola Abiola; Seedat, Soraya, 1966-; Ohaeri, Jude; Akindele, Abidemi; Aina, OluwagbemigaAtypical antipsychotics, despite their rapid dissociation from dopamine receptors and reduced tendency to induce oxidative stress, have been associated with difficult-to-manage movement disorders, including tardive dyskinesia (TD). The study set out to investigate the effects of cannabidiol (CBD), a potent antioxidant, on risperidone-induced behavioural and motor disturbances; namely vacuous chewing movements (VCM), and oxidative stress markers (e.g. superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), malondialdehyde (MDA), Nitric oxide (NO), and DPPH (2,2-diphenyl-1-picrylhydrazyl)). Oral risperidone (10 mg/kg) or oral CBD (5 mg/kg) were administered to six experimental groups. While risperidone alone was administered for 28 days, CBD concomitantly or in sequential order with risperidone, was administered for 28 days; and CBD alone was administered for 21 days. Behavioural, motor, and specific biochemical parameters, which included VCM, muscle tone, fasting blood sugar (FBS), and oxidative stress markers were assessed at different time points after the last dose of medication. Oral CBD (5 mg/kg) significantly reduced risperidone-induced elevated FBS when given after the administration of risperidone. Oral CBD also had effects on VCM when administered before risperidone and similarly, attenuated risperidone-induced increased muscle tone. It was also established that concomitant or sequential administration of CBD and risperidone did not have any adverse effects on cognition or locomotion. Both CBD and risperidone increased the activity of antioxidant enzymes and decreased the activity of pro-oxidant enzymes. This study suggests CBD could mitigate metabolic dysregulation and extrapyramidal side effects associated with risperidone without producing cognitive impairments.
- ItemPatterning of individual variability in neurocognitive health among South African women exposed to childhood maltreatment(Nature, 2021-03) Denckla, Christy A.; Lee, Sun Yeop; Kim, Rockli; Spies, Georgina; Vasterling, Jennifer J.; Subramanian, S. V.; Seedat, SorayaThere are individual differences in health outcomes following exposure to childhood maltreatment, yet constant individual variance is often assumed in analyses. Among 286 Black, South African women, the association between childhood maltreatment and neurocognitive health, defined here as neurocognitive performance (NP), was first estimated assuming constant variance. Then, without assuming constant variance, we applied Goldstein’s method (Encyclopedia of statistics in behavioral science, Wiley, 2005) to model “complex level-1 variation” in NP as a function of childhood maltreatment. Mean performance in some tests of information processing speed (Digit-symbol, Stroop Word, and Stroop Color) lowered with increasing severity of childhood maltreatment, without evidence of significant individual variation. Conversely, we found significant individual variation by severity of childhood maltreatment in tests of information processing speed (Trail Making Test) and executive function (Color Trails 2 and Stroop Color-Word), in the absence of mean differences. Exploratory results suggest that the presence of individual-level heterogeneity in neurocognitive performance among women exposed to childhood maltreatment warrants further exploration. The methods presented here may be used in a person-centered framework to better understand vulnerability to the toxic neurocognitive effects of childhood maltreatment at the individual level, ultimately informing personalized prevention and treatment.
- ItemEvaluation of an undergraduate psychiatric clinical rotation : exploring student perceptions(AOSIS, 2021-05) Smit, Inge M.; Volschenk, Mariette; Koen, LiezlBackground: Globally, the appropriate transformation of medical training is critical to ensure the graduation of competent physicians who can address the growing health needs. Aim: To explore medical students’ perceptions of their learning experience during the undergraduate psychiatry late clinical rotation (PLCR) at Stellenbosch University (SU) and to use the findings to make possible recommendations regarding curriculum renewal. Setting: In recognition of this, the Department of Psychiatry at the Faculty of Medicine and Health Sciences of SU is reviewing its current teaching and learning practices. Methods: Data were collected from two focus groups. Results: Three main themes emerged: ‘learning in the clinical context’, ‘gaining knowledge’ and ‘generational needs’. Whilst several suggestions were made for potential improvement, the participants still endorsed that the PLCR does provide them with a good learning experience in psychiatry. Conclusions: Considering that these perceptions are from a group of millennials, the insights arising from the ‘generational needs’ theme were especially valuable. To bridge the generational gap and develop a curriculum that will not only meet the standards expected by educators but also achieve acceptance from learners, future research with a specific focus on clinical teachers’ perceptions is needed.