Sex and Diffusion Tensor Imaging of White Matter in Schizophrenia: A Systematic Review Plus Meta-analysis of the Corpus Callosum

Sex is considered an understudied variable in health research. Schizophrenia is a brain disorder with known sex differences in epidemiology and clinical presentation. We systematically reviewed the literature for sex-based differences of diffusion properties of white matter tracts in schizophrenia. We then conducted a meta-analysis examining sex-based differences in the genu and splenium of the corpus callosum in schizophrenia. Medline and Embase were searched to identify relevant papers. Studies fulfilling the following criteria were included: (1) included individuals with a diagnosis of schizophrenia, (2) included a control group of healthy individuals, (3) included both sexes in the patient and the control groups, (4) used diffusion tensor imaging, and (5) involved analyzing metrics of white matter microstructural integrity. Fractional anisotropy (FA) was used as the measure of interest in the meta-analysis. Of 730 studies reviewed, 75 met the inclusion criteria. Most showed no effect of sex, however, those that did found either that females have lower FA than males, or that the effect of disease in females is larger than that in males. The findings of the meta-analysis in the corpus callosum supported this result. There is a recognized need for studies on schizophrenia with a sufficient sample of female patients. Lack of power undermines the ability to detect sex-based differences. Understanding the sex-specific impact of illness on neural circuits may help inform development of new treatments, and improvement of existing interventions

Early Psychosis Intervention-Spreading Evidence-based Treatment (EPI-SET) : Protocol for an effectiveness-implementation study of a structured model of care for psychosis in youth and emerging adults

Introduction While early psychosis intervention (EPI) has proliferated in recent years amid evidence of its effectiveness, programmes often struggle to deliver consistent, recovery-based care. NAVIGATE is a manualised model of EPI with demonstrated effectiveness consisting of four components: individualised medication management, individual resiliency training, supported employment and education and family education. We aim to implement NAVIGATE in geographically diverse EPI programmes in Ontario, Canada, evaluating implementation and its effect on fidelity to the EPI model, as well as individual-level outcomes (patient/family member-reported and interviewer-rated), system-level outcomes (captured in provincial administrative databases) and engagement of participants with lived experience. Methods and analysis This is a multisite, non-randomised pragmatic hybrid effectiveness-implementation type III mixed methods study coordinated at the Centre for Addiction and Mental Health (CAMH) in Toronto. Implementation is supported by the Provincial System Support Program, a CAMH-based programme with provincial offices across Ontario, and Extension of Community Healthcare Outcomes Ontario Mental Health at CAMH and the University of Toronto. The primary outcome is fidelity to the EPI model as measured using the First Episode Psychosis Services-Fidelity Scale. Four hundred participants in the EPI programmes will be recruited and followed using both individual-level assessments and health administrative data for 2 years following NAVIGATE initiation. People with lived experience will be engaged in all aspects of the project, including through youth and family advisory committees. Ethics and dissemination Research ethics board approval has been obtained from CAMH and institutions overseeing the local EPI programmes. Study findings will be reported in scientific journal articles and shared with key stakeholders including youth, family members, programme staff and policymakers. Trial registration number NCT03919760; Pre-results

Resting-State Connectivity Biomarkers of Cognitive Performance and Social Function in Individuals With Schizophrenia Spectrum Disorder and Healthy Control Subjects

BACKGROUND: Deficits in neurocognition and social cognition are drivers of reduced functioning in schizophrenia spectrum disorders, with potentially shared neurobiological underpinnings. Many studies have sought to identify brain-based biomarkers of these clinical variables using a priori dichotomies (e.g., good vs. poor cognition, deficit vs. nondeficit syndrome). METHODS: We evaluated a fully data-driven approach to do the same by building and validating a brain connectivity-based biomarker of social cognitive and neurocognitive performance in a sample using resting-state and task-based functional magnetic resonance imaging (n = 74 healthy control participants, n = 114 persons with schizophrenia spectrum disorder, 188 total). We used canonical correlation analysis followed by clustering to identify a functional connectivity signature of normal and poor social cognitive and neurocognitive performance. RESULTS: Persons with poor social cognitive and neurocognitive performance were differentiated from those with normal performance by greater resting-state connectivity in the mirror neuron and mentalizing systems. We validated our findings by showing that poor performers also scored lower on functional outcome measures not included in the original analysis and by demonstrating neuroanatomical differences between the normal and poorly performing groups. We used a support vector machine classifier to demonstrate that functional connectivity alone is enough to distinguish normal and poorly performing participants, and we replicated our findings in an independent sample (n = 75). CONCLUSIONS: A brief functional magnetic resonance imaging scan may ultimately be useful in future studies aimed at characterizing long-term illness trajectories and treatments that target specific brain circuitry in those with impaired cognition and function

Antidepressant Controlled Trial For Negative Symptoms In Schizophrenia (ACTIONS): a double-blind, placebo-controlled, randomised clinical trial

Background Negative symptoms of schizophrenia represent deficiencies in emotional responsiveness, motivation, socialisation, speech and movement. When persistent, they are held to account for much of the poor functional outcomes associated with schizophrenia. There are currently no approved pharmacological treatments. While the available evidence suggests that a combination of antipsychotic and antidepressant medication may be effective in treating negative symptoms, it is too limited to allow any firm conclusions. Objective To establish the clinical effectiveness and cost-effectiveness of augmentation of antipsychotic medication with the antidepressant citalopram for the management of negative symptoms in schizophrenia. Design A multicentre, double-blind, individually randomised, placebo-controlled trial with 12-month follow-up Setting Adult psychiatric services, treating people with schizophrenia. Participants Inpatients or outpatients with schizophrenia, on continuing, stable antipsychotic medication, with persistent negative symptoms at a criterion level of severity. Interventions Eligible participants were randomised 1 : 1 to treatment with either placebo (one capsule) or 20 mg of citalopram per day for 48 weeks, with the clinical option at 4 weeks to increase the daily dosage to 40 mg of citalopram or two placebo capsules for the remainder of the study. Main Outcome Measures The primary outcomes were quality of life measured at 12 and 48 weeks assessed using the Heinrich’s Quality of Life Scale, and negative symptoms at 12 weeks measured on the negative symptom subscale of the Positive and Negative Syndrome Scale. Results No therapeutic benefit in terms of improvement in quality of life or negative symptoms was detected for citalopram over 12 weeks or at 48 weeks, but secondary analysis suggested modest improvement in the negative symptom domain, avolition/amotivation, at 12 weeks (mean difference –1.3, 95% confidence interval–2.5 to–0.09). There were no statistically significant differences between the two treatment arms over 48-week follow-up in either the health economics outcomes or costs, and no differences in the frequency or severity of adverse effects, including corrected QT interval prolongation. Limitations The trial under-recruited, partly because cardiac safety concerns about citalopram were raised, with the 62 participants recruited falling well short of the target recruitment of 358. Although this was the largest sample randomised to citalopram in a randomised controlled trial of antidepressant augmentation for negative symptoms of schizophrenia and had the longest follow-up, the power of statistical analysis to detect significant differences between the active and placebo groups was limited. Conclusion Although adjunctive citalopram did not improve negative symptoms overall, there was evidence of some positive effect on avolition/amotivation, recognised as a critical barrier to psychosocial rehabilitation and achieving better social and community functional outcomes. Comprehensive assessment of side-effect burden did not identify any serious safety or tolerability issues. The addition of citalopram as a long-term prescribing strategy for the treatment of negative symptoms may merit further investigation in larger studies. Future Work Further studies of the viability of adjunctive antidepressant treatment for negative symptoms in schizophrenia should include appropriate safety monitoring and use rating scales that allow for evaluation of avolition/amotivation as a discrete negative symptom domain. Overcoming the barriers to recruiting an adequate sample size will remain a challenge.</p

ED to EPI : Protocol for a pragmatic randomised controlled trial of an SMS (text) messaging intervention to improve the transition from the emergency department to early psychosis intervention for young people with psychosis

Introduction While nearly half of all new psychotic disorders are diagnosed in the emergency department (ED), most young people who present to the ED with psychosis do not receive timely follow-up with a psychiatrist, and even fewer with evidence-based early psychosis intervention (EPI) services. We aim to test an intervention delivered using short message service (SMS), a low-cost, low-complexity, youth-friendly approach, to improve transitions from the ED to EPI services. Methods and analysis This is a protocol for a pragmatic randomised, single blind, controlled trial with accompanying economic and qualitative evaluations conducted at the Centre for Addiction and Mental Health (CAMH) in Toronto, Canada. A consecutive series of 186 participants aged 16-29 referred by the ED to CAMH's EPI programme will be recruited for a trial of a two-way intervention involving reminders, psychoeducation and check-ins delivered via SMS. The primary outcome will be attendance at the first consultation appointment within 30 days of study enrolment assessed through chart reviews in the electronic health record. We will also extract routine clinical measures, including the Brief Psychiatric Rating Scale, Clinical Global Impression and Service Engagement Scale, and link with provincial health administrative data to examine system-level outcomes, including ED visits and psychiatric hospitalisations, 6 months and up to 2 years after baseline. We will perform a cost-effectiveness analysis of the primary study outcome and costs incurred, calculating an incremental cost effectiveness ratio. Web-based surveys and qualitative interviews will explore intervention user experience. Patients and families with lived experience will be engaged in all aspects of the project. Ethics and dissemination Research Ethics Board approval has been obtained. Findings will be reported in scientific journal articles and shared with key stakeholders including youth, family members, knowledge users and decision makers. Trial registration number NCT04298450

Investigations Of The Determinants of Functional Outcomes In Schizophrenia: Cross-sectional And Longitudinal Examinations Of The Role Of Negative Symptoms

Despite significant advances in the field, functional impairment continues to be a characteristic feature of schizophrenia. Negative symptoms, and in particular motivational deficits, along with cognitive dysfunction have consistently been linked with functional impairments in schizophrenia. However, most investigations of functional outcomes have focused on discrete symptoms, or alternatively on broad symptom domains. Further, recent findings have suggested that a lack of motivation may contribute to the cognitive impairment seen in schizophrenia. This series of investigations sought to: 1) advance our understanding of the determinants of cross- sectional and longitudinal community functioning in schizophrenia by examining the concurrent contribution of negative symptoms, cognition, and other important symptoms to longitudinal functioning in schizophrenia over one year; and 2) clarify the relationships between motivation, effort exerted during cognitive testing, and cognitive performance in schizophrenia. We hypothesized that: 1) motivational deficits would serve as the most important and stable determinant of community functioning, with cognition offering additional predictive value; and 2) motivational deficits would exhibit a differential relationship across various cognitive domains, with those exhibiting reduced effort during testing evincing more severe motivational deficits. Seventy stable adult outpatients with schizophrenia or schizoaffective disorder underwent clinical, cognitive, and functional evaluations at baseline, 6 months, and 12 months. Using stepwise and hierarchical regression analyses, motivational deficits emerged as the most predictive and reliable determinant of cross-sectional and longitudinal community functioning, accounting for up to 58% of the variance in functioning. Other symptom domains exhibited substantially less predictive value for functioning. Motivational deficits also exhibited a differential relationship across cognitive domains, with a particular relationship with verbal fluency. Further, effort during cognitive testing appeared to be related to both cognitive dysfunction and motivation, suggesting that the use of performance validity tests in schizophrenia may not be an appropriate index of mental effort. Overall, these findings highlight the central role motivational deficits play in determining outcomes in schizophrenia, as well as their impact on cognitive dysfunction in this illness. Importantly, in spite of advances in treatment, this work points to the essential need for interventions to address these motivational deficits if we hope to improve outcomes in schizophrenia.Ph

Identification, characterization, and mapping of novel members of the Siglec family

grantor: University of TorontoThe sialic acid binding immunoglobulin-like lectin (Siglec) family is a recently described member of the immunoglobulin superfamily. Within this Siglec family there exists a subgroup of molecules which bear a very high degree of homology with the molecule Siglec-3 (CD33), thus designated the Siglec-3-like subgroup of Siglecs. Members of this subgroup have been localized to chromosome 19q13.4, primarily through in situ hybridization. Through our investigation of chromosome 19q13.3-13.4, we identified, and precisely characterized three genes belonging to this Siglec-3-like subgroup. We identified the novel Siglec-9, located adjacent to the human Kallikrein gene family on chromosome 19q13.4, and the previously reported Siglec-8 gene downstream of Siglec-9, for which we characterized a novel transcript. Finally, we identified and mapped another novel Siglec-like gene, and characterized two splice variants. From preliminary studies, all Siglec-3-like subgroup members may play an inhibitory role of haemopoietic cell proliferation, and have some utility in antineoplastic therapy.M.Sc

An Examination of the Multi-Faceted Motivation System in Healthy Young Adults

Background: Amotivation is a prevalent symptom in schizophrenia (SZ) and depression (MDD), and is linked to poor functional outcomes in affected individuals. Conceptualizations of motivation have outlined a multi-faceted construct comprised of reward responsiveness, reward expectancy, reward valuation, effort valuation, and action selection/preference-based decision making. To date, findings from studies utilizing variable-centered approaches to examining isolated facets of motivation in SZ and MDD have been inconsistent. Thus, the present study adopted a person-centered approach, and comprehensively examined the reward system in a non-clinical sample in an attempt to explore potential subtypes of motivation impairments, while minimizing the effects of illness-related confounds.Methods: Ninety-six healthy undergraduate students were evaluated for amotivation, schizotypal traits, depressive symptoms, and cognition, and administered objective computerized tasks to measure the different facets of motivation. Cluster analysis was performed to explore subgroups of individuals based on similar motivation task performance. Additionally, correlational analyses were conducted in order to examine inter-relationships between motivation facets, and relations between clinical measures and facets of motivation.Results: Cluster analysis identified two subgroups of individuals with differential motivation performance profiles. Correlational analyses revealed that reward responsiveness was associated with amotivation, depressive symptoms, and negative schizotypy. Further, significant inter-correlations were found between reward responsiveness and reward expectancy, as well as between reward valuation and effort valuation.Conclusions: Our results mark important steps forward in understanding motivation in a non-clinical sample, and guide future dimensional and comprehensive analyses of the multi-faceted reward system. It remains to be seen whether these patterns of results will be similar in clinical populations such as SZ and MDD