Characterizing psychosis risk traits in Africa: A longitudinal study of Kenyan adolescents

Epidemiology of DSM-5 psychiatric disorders in Kenyan Youth with Low and High Psychosis Risk

INTRODUCTION

There are few psychiatric epidemiology studies among Kenyan youth and fewer among those at high psychosis risk (HR).

METHODS

This study assessed the epidemiology of DSM-5 psychiatric disorders in HR and low-risk (LR) individuals to inform research and mental health services. 567 participants (aged 15-25) in HR (n = 246) and LR (n = 260) groups based on Washington Early Recognition Center Affectivity and Psychosis (WERCAP) Screen scores. Diagnostic Interview Schedule, version 5 (DIS-5) assessed DSM-5 psychiatric disorder prevalence. Diagnostic comorbidity and demographic relationships were investigated.

RESULTS

A higher prevalence was observed for all DSM-5 disorders in the HR group, significantly for gambling disorder (13% vs. 5.8%), major depressive disorder (9.8% vs. 3.8%), antisocial personality disorder (5.7% vs. 2.3%), general anxiety disorder (4.9% vs. 0.4%), oppositional defiant disorder (3.3% vs. 0.4%), panic disorder (2.8% vs. 0.8%), and anorexia nervosa (2.8% vs. 0%). Gambling disorder was the most prevalent and showed significant gender effects (males>females).

DISCUSSION

Psychiatric disorders occur at increased rates among HR compared to LR. Prevalence rates found are lower than in US studies, except for gambling disorder which was highly prevalent. Large-population-based epidemiology studies in Africa are needed to estimate rates, particularly of disorders such as schizophrenia, accurately.

Psychotic-like experiences and adverse life events in young people. Does gender matter?

BACKGROUND

Psychotic-like experiences (PLEs) and adverse life events (ALEs) are highly prevalent in sub-Saharan Africa where gendered practices are also common. There is, however, a paucity of data on how the relationship between PLEs and life adversities is influenced by gender. The current study addressed this gap.

METHOD

Data were collected from 1886 school-based young people (1174 females) in Ghana, West Africa using a cross-sectional survey methodology and analyzed using Chi-square, independent t-test, Pearson correlation, and multivariate regression.

RESULTS

The results showed that victimization experiences, school stress and having a family member with mental illness were significantly associated with PLEs in both males and females. In contrast, substance misuse and experiences of head trauma correlated significantly with PLEs in females only.

CONCLUSION

Life adversities constitute major risk factors for PLEs among school-based young people in Ghana, who could benefit from gender neutral and gender-sensitive intervention programming to remediate the effects of life adversities on PLEs.

Burden and risk factors of mental and substance use disorders among adolescents and young adults in Kenya: results from the Global Burden of Disease Study 2019

Background

Mental and substance use disorders are a major public health concern globally, with high rates of disability, morbidity, and mortality associated with these. In low- and middle-income countries, such as Kenya, mental health is often given low priority, and resources for the prevention and treatment of mental and substance use disorders are limited. Adolescence and young adulthood are critical periods for the development of mental and substance use disorders, with many disorders emerging during this time. In Kenya, the burden and risk factors of mental and substance use disorders among adolescents and young adults is not well understood.

Methods

The data used in this study were obtained from the Global Burden of Disease (GBD) Study 2019. We selected the data on the number of mental and substance use disorders among adolescents and young adults in Kenya from the GBD results tool. The data were extracted by mental health (MH) condition, by age group and by sex. We used descriptive statistical methods to summarise and present the data. Specifically, we calculated the disability-adjusted life-years (DALYs) rates, risk factors of mental and substance use disorders by age group and sex.

Findings

In 2019, among 10-24-year-olds in Kenya, mental disorders ranked as the second leading cause of disability, following unintentional injuries, and accounted for 248,936 [95% uncertainty interval 175,033; 341,680] DALYs or 9.4% of 2,656,546 total DALYs. Substance use disorders accounted 15,022 [9948; 20,710] DALYs. Depressive, anxiety, and conduct disorders accounted for the most DALYs of mental disorders accounting for 3.1%, 2.3% and 1.7% of the total DALYs, respectively. The main risk factors for incident DALYs in 10-24-year-olds were bullying and victimization (66.5%). Childhood sexual abuse accounted for 13.7% of the DALYs, lead exposure accounted for 8.5% of the DALYs, intimate partner violence accounted for 11.3% of the DALYs (2%) with all victims being females, and illicit drug use accounted for (52.7%) of DALYs.

Interpretation

Improved surveillance of mental health and substance use burden at national and county levels is needed. Focus on timely screening and intervention for idiopathic developmental intellectual disability, conduct disorder, and substance use disorder in young boys and depression, anxiety, and eating disorders in young girls and women is critically needed.

Funding

MK is funded by FIC/NIMH K43 TW 010716 and R33MH124149-03. The publication was made possible by funding from the Gates Foundation.

Perspective on clinical high-risk for psychosis in Africa

Clinical High Risk for Psychosis has evolved in recent years as a conceptual and clinical entity, representing a shift in focus from the syndromal psychosis state to a recognition of the pre-psychotic state as a period of potential preventive intervention. Much existing evidence has been generated from well-resourced countries, with a more limited body of literature available from Africa and other Majority World countries. Against a backdrop of prevailing systemic challenges, it is necessary to appraise the state of knowledge on Clinical High Risk for Psychosis in Africa. In this perspective article, we cover epidemiology, risk factors, predictors of psychosis conversion, as well as an overview of sociocultural factors, notably stigma, and the barriers to mental health services in African settings. We discuss existing and promising assessment approaches and reflect on preventive and early intervention strategies. We conclude with recommendations including the need for more clinical, longitudinal, and collaborative research anchored in an integrative transdisciplinary approach. We highlight the need for more culturally valid assessment tools and strategies to improve access to and utilization of services while also reducing stigma.

The 3-year progression of clinically significant psychotic-like experiences in a general adult population in Lagos, Nigeria

PURPOSE

The study assessed the 3-year progression of clinically significant psychotic-like experience (CS-PLE) symptoms in an adult general population in terms of stability or remission of symptoms and transition to psychosis.

METHODS

Participants (n = 1292) aged 18-65 years with CS-PLE were assessed at baseline for sociodemographic details, family history of mental illness, functioning status, common mental disorders, alcohol, and substance use disorders. Three years later they were reassessed for diagnosis of psychosis, presence or remission of PLE symptoms, and contact with mental health services.

RESULTS

The mean age of the participants at baseline in years was 36.56 (SD = 11.66) and there were 855 (66.2%) females. By the 3rd year follow-up, 95 (7.3%) had transited to psychosis, while 850 (65.5%) had persistent CS-PLE symptoms and the rest 347 (27.2%) were in remission. Only history of mental illness in the immediate family (HR 4.81, 95% CI 1.40-16.47, P = 0.013) and regular use of cannabis at less than 18 years of age (HR 0.65, 95% CI 0.55-0.77, P < 0.001) were the independent predictors of conversion to psychosis at 3 years.

CONCLUSION

The rate of TTP in the non-clinical population with elevated risk may be lower than that earlier reported in the western literature. Interventions aimed at preventing transition to psychosis in high risk groups must pay attention to early onset users of cannabis and those with family history of mental illness.

A systematic review of premorbid cognitive functioning and its timing of onset in schizophrenia spectrum disorders

Cognitive impairments are core features of established schizophrenia spectrum disorders (SSD). However, it remains unclear whether specific cognitive functions are differentially impaired pre-onset and at what age these impairments can be detected. The purpose of this review was to elucidate these issues through a systematic summary of results from longitudinal studies investigating impairment in specific cognitive domains as antecedents of SSD.

Relevant studies were identified by electronic and manual literature searches and included any original study of cognitive domains any time pre-onset of SSDs that included a control group. Effect sizes were calculated by domain for studies comparing high-risk participants who developed SSD with those who did not.

The strongest evidence for impairment pre-onset was for mental processing speed, verbal learning and memory, executive function, and social cognition. Some verbal impairments, like language abilities at age 3 and verbal learning and memory at age 7, may develop as static deficits. Conversely, some non-verbal impairments, like mental processing speed, visuospatial abilities, and visual working memory manifest as developmental lag and become significant later in life. Most effect sizes were small to moderate, except for verbal fluency (d′ = 0,85), implying this impairment as central in high-risk participants who develop SSD.

The present review documents extensive cognitive impairments pre-onset of SSD, and that these impairments start early in life, in line with the neurodevelopmental hypothesis of schizophrenia. Increased knowledge about cognitive impairments preonset can provide a better basis for understanding the complex pathogenesis of SSD as well as informing cognitive remediation programs.

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Specific cognitive domains evidence differential impairment pre-onset.

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Most effect sizes were small to moderate.

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Some verbal impairments develop as static deficits from early childhood.

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Some non-verbal impairments present as developmental lag and become apparent later.

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Impairments start early in life, in line with the neurodevelopmental hypothesis.

Longitudinal and cross-sectional validation of the WERCAP screen for assessing psychosis risk and conversion

BACKGROUND

The Washington Early Recognition Center Affectivity and Psychosis (WERCAP) Screen was developed to assess risk for developing psychosis. Its validity has not been investigated in a large population-based study or with longitudinal analyses.

METHODS

825 participants, aged 14-25, were recruited from Kenya. Symptoms were assessed using the WERCAP Screen, as experienced over the prior 3-months (3MO), 12-months (12MO) or lifetime (LIF). ROC curve analysis was used to determine the validity of the WERCAP Screen against the Structured Interview of Psychosis-Risk Syndromes. Longitudinal validity was assessed by comparing baseline p-WERCAP scores in psychotic disorder converters and non-converters, and using ROC curve analysis. Relationship of the p-WERCAP was examined against clinical variables.

RESULTS

ROC curve analyses against SIPS showed an AUC of 0.83 for 3MO, 0.79 for 12MO and 0.65 for LIF psychosis scores. The optimal cut-point on 3MO was a score of >12 (sens: 0.78; spec: 0.77; ppv: 0.41), and >32 for 12MO (sens: 0.71; spec: 0.74; ppv: 0.24). Baseline 3MO scores (but not LIF scores) were higher in converters compared to high-risk non-converters (p = 0.02). 3MO scores against conversion status had an AUC of 0.75, with an optimal cutoff point of >16 (sens: 1.0; spec: 0.53). All p-WERCAP scores significantly correlated with substance use and stress severity. 12 MO scores were most related to cognitive impairment.

CONCLUSIONS

The WERCAP Screen is a valid instrument for assessing psychosis severity and conversion risk. It can be used in the community to identify those who may require clinical assessment and care, and for recruitment in psychosis-risk research.

The prevalance of binge eating disorder and associated psychiatric and substance use disorders in a student population in Kenya - towards a public health approach

INTRODUCTION

Kenya in particular and Africa in general lack data on Binge Eating Disorder (BED). The overarching objective of this study is to fill that gap. Kenyans may not be aware that BED exists when a "very good" appetite is considered a sign of good health, especially if food is available either at home, in fast food shops or when communally eating together, a very common cultural practice. On the other hand where there is relatively insufficient food, it is not expected that one could be having a problem of eating too much.

METHOD

We administered the following tools and measurements to 9742 participants (high school, college and university students): 1) Researcher designed socio-demographic and economic indicator questionnaire; 2) An instrument documenting DSM-IV diagnostic criteria for BED and its various symptoms; 3) An instrument to determine DSM-IV psychiatric disorders and substance abuse;4) An instrument measuring high risk for psychosis ,affectivity and stress; 5) A WHO designed instrument measuring the severity of substance abuse for specific substances. We used descriptive and inferential analysis to determine the prevalence and association of the different variables. Independent predictors of BED were generated from a generalized linear model (p<0.05).

RESULTS

We found a prevalence of 3.2% of BED and a wide range of prevalence for BED and BED related symptoms (8.1% to 19%). The least prevalent was "To prevent weight gain from eating binge did you force yourself to vomit, or used laxatives?". The most common was "Did you often go on eating binges (eating a very large amount of food very quickly over a short period of time)." Major depression, obsessive compulsive disorder, panic disorder, agoraphobia, generalized anxiety disorder ,a positive stress screen and drug abuse were independent predictors of BED (p<0.05).

CONCLUSION

Our findings on the prevalence of BED and significant associations with various psychiatric disorders and substance use disorders are similar to those obtained in High Income Countries (HIC) using similar large-scale samples in non-clinical populations. Our findings suggest the need fora public health approach to enhance awareness of BED and to promote health-seeking behaviour towards management of BED.

Association between formal thought disorders, neurocognition and functioning in the early stages of psychosis: a systematic review of the last half-century studies

Recent review articles provided an extensive collection of studies covering many aspects of format thought disorders (FTD) among their epidemiology and phenomenology, their neurobiological underpinnings, genetics as well as their transdiagnostic prevalence. However, less attention has been paid to the association of FTD with neurocognitive and functioning deficits in the early stages of evolving psychosis. Therefore, this systematic review aims to investigate the state of the art regarding the association between FTD, neurocognition and functioning in the early stages of evolving psychotic disorders in adolescents and young adults, by following the PRISMA flowchart. A total of 106 studies were screened. We included 8 studies due to their reports of associations between FTD measures and functioning outcomes measured with different scales and 7 studies due to their reports of associations between FTD measures and neurocognition. In summary, the main findings of the included studies for functioning outcomes showed that FTD severity predicted poor social functioning, unemployment, relapses, re-hospitalisations, whereas the main findings of the included studies for neurocognition showed correlations between attentional deficits, executive functions and FTD, and highlighted the predictive potential of executive dysfunctions for sustained FTD. Further studies in upcoming years taking advantage of the acceleration in computational psychiatry would allow researchers to re-investigate the clinical importance of FTD and their role in the transition from at-risk to full-blown psychosis conditions. Employing automated computer-assisted diagnostic tools in the early stages of psychosis might open new avenues to develop targeted neuropsychotherapeutics specific to FTD.

Diagnosis, prognosis, and treatment of brief psychotic episodes: a review and research agenda

Brief psychotic episodes represent an intriguing paradox in clinical psychiatry because they elude the standard knowledge that applies to the persisting psychotic disorders such as schizophrenia. This Review describes key diagnostic considerations such as conceptual foundations, current psychiatric classification versus research-based operationalisations, epidemiology, and sociocultural variations; prognostic aspects including the risk of psychosis recurrence, types of psychotic recurrences, other clinical outcomes, prognostic factors; and therapeutic issues such as treatment guidelines and unmet need of care. The advances and challenges associated with the scientific evidence are used to set a research agenda in this area. We conclude that brief psychotic episodes can be reconceptualised within a clinical staging model to promote innovative translational research and improve our understanding and treatment of psychotic disorders.

Psychotic-like experiences among 9,564 Kenyan adolescents and young adults

OBJECTIVE

To investigate the prevalence and characteristics of psychotic-like experiences (PLE) in a large cohort of Kenyan adolescents and young adults.

METHOD

The Washington Early Recognition Center Affectivity and Psychosis (WERCAP) Screen was used to the study the 12-month prevalence of PLE's among 9,564 Kenyan youths (aged 15-25 yrs), and the rates of psychosis high-risk (HR) and medium-risk (MR) cases, based on cut-off scores. Relationships with clinical, demographic and economic profiles were investigated.

RESULTS

Across all participants, 72% reported having had at least one PLE over the last year. 4.6% and 30.6% were HR and MR based on symptom scores. There were similar PLE rates in females and males. PLE severity correlated with mood (r=0.67), stress (r=0.46), and autistic traits (r=0.18). PLE severity was also related to poverty, lower education attainment, and underemployment. Compared to controls, HR and MR youths were more likely to report lifetime substance use and to have more significant use.

CONCLUSION

Psychosis screening can provide valuable information about individuals and may help identify those who may require clinical assessment and intervention to improve outcomes. This is particularly relevant in many parts of Africa where the resources are limited for treating more advanced illness.

Neurocognition in Kenyan youth at clinical high risk for psychosis

Introduction

Cognitive deficits are typically seen in schizophrenia and in the prodrome, and are a major predictor of functional outcomes in patients. In Africa, few studies have investigated neurocognition in psychosis, which presents a gap in our understanding of the heterogeneity of the illness. In this study, we assessed neurocognition among the largest sample of psychosis-risk participants recruited in the continent to date.

Methods

The study was conducted in Kenya, and involved 295 psychiatric medication-naïve participants at clinical high-risk (CHR) for psychosis and healthy controls, aged 15–25 yrs. Psychosis-risk status was determined separately using the Structured Interview of Psychosis-Risk Syndromes (i.e. CHR) and by self-report with the Washington Early Recognition Center Affectivity and Psychosis Screen. Eleven tests were administered using the University of Pennsylvania Computerized Neurocognitive Battery. Test performance across groups were investigated, as well as demographic and clinical effects.

Results

Fewer participants were designated as being at psychosis-risk with structured interview (n = 47; CHR) than with self-report (n = 155). A MANOVA of cognitive test performance was significant only when groups were ascertained based on self-report (p = 0.03), with decreased performance in the risk group on verbal intelligence (p = 0.003; d = 0.39), emotion recognition (p = 0.003; d = 0.36), sensorimotor processing (p = 0.01; d = 0.31) and verbal memory (p = 0.035; d = 0.21). Only verbal intelligence was significantly worse in the CHR group compared to controls (p = 0.036; d = 0.45). There were no significant age and gender relationships.

Conclusion

Deficits across multiple cognitive domains are present in Kenyan psychosis-risk youth, most significantly in verbal intelligence. The pattern of cognitive deficits and an absence of gender effects may represent ethnicity-specific phenotypes of the psychosis-risk state. Longitudinal studies of neurocognition in Kenyan patients who convert to psychosis may enhance risk prediction in this population, and facilitate targeted interventions.

Predicting the individual risk of psychosis conversion in at-risk mental state (ARMS): a multivariate model reveals the influence of nonpsychotic prodromal symptoms

To improve the prediction of the individual risk of conversion to psychosis in UHR subjects, by considering all CAARMS' symptoms at first presentation and using a multivariate machine learning method known as logistic regression with Elastic-net shrinkage. 46 young individuals who sought help from the specialized outpatient unit at Sainte-Anne hospital and who met CAARMS criteria for UHR were assessed, among whom 27 were reassessed at follow-up (22.4 ± 6.54 months) and included in the analysis. Elastic net logistic regression was trained, using CAARMS items at baseline to predict individual evolution between converters (UHR-P) and non-converters (UHR-NP). Elastic-net was used to select the few CAARMS items that best predict the clinical evolution. All validations and significances of predictive models were computed with non-parametric re-sampling strategies that provide robust estimators even when the distributional assumption cannot be guaranteed. Among the 25 CAARMS items, the Elastic net selected 'obsessive-compulsive symptoms' and 'aggression/dangerous behavior' as risk factors for conversion while 'anhedonia' and 'mood swings/lability' were associated with non-conversion at follow-up. In the ten-fold stratified cross-validation, the classification achieved 81.8% of sensitivity (P = 0.035) and 93.7% of specificity (P = 0.0016). Non-psychotic prodromal symptoms bring valuable information to improve the prediction of conversion to psychosis. Elastic net logistic regression applied to clinical data is a promising way to switch from group prediction to an individualized prediction.

Personality Traits as Markers of Psychosis Risk in Kenya: Assessment of Temperament and Character

Specific personality traits have been proposed as a schizophrenia-related endophenotype and confirmed in siblings at risk for psychosis. The relationship of temperament and character with psychosis has not been previously investigated in Africa. The study was conducted in Kenya, and involved participants at clinical high-risk (CHR) for psychosis (n = 268) and controls (n = 251), aged 15–25 years. CHR status was estimated using the Structured Interview of Psychosis-Risk Syndromes (SIPS) and the Washington Early Psychosis Center Affectivity and Psychosis (WERCAP) Screen. Student’s t-tests were used to assess group differences on the Temperament and Character Inventory (TCI). Neurocognitive functioning, stress severity, and substance use were correlated with the TCI, correcting for psychosis severity. CHR participants were more impulsive (ie, higher novelty seeking [NS]) and asocial (ie, lower reward dependence) than controls. They were also more schizotypal (ie, high self-transcendence [ST] and lower self-directedness [SD] and cooperativeness [CO] than controls). CO was related to logical reasoning, abstraction, and verbal memory. Stress severity correlated with high HA and schizotypal character traits. Lifetime tobacco use was related to NS, and lifetime marijuana use to high NS, low SD and high ST. Temperament and character of Kenyan CHR youth is similar to that observed in schizophrenia. Psychosis risk in Kenya is associated with impulsive, asocial, and schizotypal traits. CHR adolescents and young adults with schizophrenia-specific personality traits may be most at risk for developing a psychotic disorder and to require early intervention to improve outcomes.

The psychometric properties of the Washington Early Recognition Center Affectivity and Psychosis (WERCAP) screen in adults in the Kenyan context: Towards combined large scale community screening for affectivity and psychosis

There is a need for screening for early symptoms of psychosis and affectivity at community level to promote early diagnosis and management. Any screening instrument should have good psychometric properties. One such instrument is the Washington Early Recognition Center Affectivity and Psychosis (WERCAP) Screen that has been used in the USA, Kenya and Rwanda. However, its properties have not been studied outside the USA, and not in adults. The study aims to document the psychometric properties of the WERCAP Screen in Kenyan adults with positive screens on the WHO mental health treatment GAP- Intervention Guidelines (mhGAP-IG). We administered the WERCAP Screen and a gold standard - the Mini-International Neuropsychiatric Interview (MINI-Plus) section on psychosis to 674 Kenyan adults who had screened positive on the WHO mhGAP-IG. Out of these, 464 (68.84%) scored positive for both affectivity and psychosis sections on the MINI-Plus. The WERCAP affectivity and psychosis scales had good psychometric properties as screening measures, with a cut-off point of 22 for affectivity and 20 for psychosis. The WERCAP Screen has the potential for combined scale up screening for affectivity and psychosis in Kenyan population.

Cultural differences in positive psychotic experiences assessed with the Community Assessment of Psychic Experiences-42 (CAPE-42): a comparison of student populations in the Netherlands, Nigeria and Norway

BACKGROUND

Previous studies have suggested that culture impacts the experience of psychosis. The current study set out to extend these findings by examining cultural variation in subclinical positive psychotic experiences in students from The Netherlands, Nigeria, and Norway. Positive psychotic experiences were hypothesized to (i) be more frequently endorsed by, and (ii) cause less distress in Nigerian vs. Dutch and Norwegian students.

METHODS

Psychology students, aged 18 to 30 years, from universities in the Netherlands (n = 245), Nigeria (n = 478), and Norway (n = 162) were assessed cross-sectionally with regard to the frequency of subclinical positive psychotic experiences and related distress, using the Community Assessment of Psychic Experiences (CAPE-42). Multi-group confirmatory factor analysis and multivariate analysis of covariance were performed to assess measurement invariance of the positive symptom dimension (CAPE-Pos) and compare mean frequency and associated distress of positive psychotic experiences across study samples.

RESULTS

Only CAPE-Pos items pertaining to the dimensions 'strange experiences' and 'paranoia' met assumptions for (partial) measurement invariance. Frequencies of these experiences were higher in the Nigerian sample, compared to both the Dutch and Norwegian samples, which were similar. In addition, levels of experience-related distress were similar or higher in the Nigerian sample compared to respectively the Dutch and Norwegian samples.

CONCLUSION

Although positive psychotic experiences may be more commonly endorsed in non-Western societies, our findings do not support the notion that they represent a more benign, and hence less distressing aspect of human experience. Rather, the experience of psychotic phenomena may be just as, if not more, distressing in African than in European culture. However, observed differences in CAPE-Pos frequency and distress between samples from different cultural settings may partly reflect differences in the measure rather than in the latent trait. Future studies may therefore consider further cross-cultural adaptation of CAPE-42, in addition to explicitly examining cultural acceptance of psychotic phenomena, and environmental and other known risk factors for psychosis, when comparing and interpreting subclinical psychotic phenomena across cultural groups.

Short clinically-based prediction model to forecast transition to psychosis in individuals at clinical high risk state

Objective:

The predictive accuracy of the Clinical High Risk criteria for Psychosis (CHR-P) regarding the future development of the disorder remains suboptimal. It is therefore necessary to incorporate refined risk estimation tools which can be applied at the individual subject level. The aim of the study was to develop an easy-to use, short refined risk estimation tool to predict the development of psychosis in a new CHR-P cohort recruited in European country with less established early detection services.

Methods:

A cohort of 105 CHR-P individuals was assessed with the Comprehensive Assessment of At Risk Mental States12/2006, and then followed for a median period of 36 months (25th-75th percentile:10–59 months) for transition to psychosis. A multivariate Cox regression model predicting transition was generated with preselected clinical predictors and was internally validated with 1000 bootstrap resamples.

Results:

Speech disorganization and unusual thought content were selected as potential predictors of conversion on the basis of published literature. The prediction model was significant (p < 0.0001) and confirmed that both speech disorganization (HR = 1.69; 95%CI: 1.39–2.05) and unusual thought content (HR = 1.51; 95%CI: 1.27–1.80) were significantly associated with transition. The prognostic accuracy of the model was adequate (Harrell’s c- index = 0.79), even after optimism correction through internal validation procedures (Harrell’s c-index = 0.78).

Conclusions:

The clinical prediction model developed, and internally validated, herein to predict transition from a CHR-P to psychosis may be a promising tool for use in clinical settings. It has been incorporated into an online tool available at:https://link.konsta.com.pl/psychosis. Future external replication studies are needed.

A Comprehensive Review of Computational Methods for Automatic Prediction of Schizophrenia With Insight Into Indigenous Populations

Psychiatrists rely on language and speech behavior as one of the main clues in psychiatric diagnosis. Descriptive psychopathology and phenomenology form the basis of a common language used by psychiatrists to describe abnormal mental states. This conventional technique of clinical observation informed early studies on disturbances of thought form, speech, and language observed in psychosis and schizophrenia. These findings resulted in language models that were used as tools in psychosis research that concerned itself with the links between formal thought disorder and language disturbances observed in schizophrenia. The end result was the development of clinical rating scales measuring severity of disturbances in speech, language, and thought form. However, these linguistic measures do not fully capture the richness of human discourse and are time-consuming and subjective when measured against psychometric rating scales. These linguistic measures have not considered the influence of culture on psychopathology. With recent advances in computational sciences, we have seen a re-emergence of novel research using computing methods to analyze free speech for improving prediction and diagnosis of psychosis. Current studies on automated speech analysis examining for semantic incoherence are carried out based on natural language processing and acoustic analysis, which, in some studies, have been combined with machine learning approaches for classification and prediction purposes.

White matter integrity in schizophrenia and bipolar disorder: Tract- and voxel-based analyses of diffusion data from the Connectom scanner

Background

Diffusion imaging abnormalities have been associated with schizophrenia (SZ) and bipolar disorder (BD), indicating impaired structural connectivity. Newer methods permit the automated reconstruction of major white matter tracts from diffusion-weighted MR images in each individual's native space. Using high-definition diffusion data from SZ and BP subjects, we investigated brain white matter integrity using both an automated tract-based and voxel-based methods.

Methods

Using a protocol matched to the NIH (Young-Adult) Human Connectome Project (and collected on the same customized ‘Connectom’ scanner), diffusion scans were acquired from 87 total participants (aged 18–30), grouped as SZ (n = 24), BD (n = 33) and healthy controls (n = 30). Fractional anisotropy (FA) of eighteen white matter tracks were analyzed using the TRACULA software. Voxel-wise statistical analyses of diffusion data was carried out using the tract-based spatial statistics (TBSS) software. TRACULA group effects and clinical correlations were investigated using analyses of variance and multiple regression.

Results

TRACULA analysis identified a trend towards lower tract FA in SZ patients, most significantly in the left anterior thalamic radiation (ATR; p = .04). TBSS results showed significantly lower FA voxels bilaterally within the cerebellum and unilaterally within the left ATR, posterior thalamic radiation, corticospinal tract, and superior longitudinal fasciculus in SZ patients compared to controls (FDR corrected p < .05). FA in BD patients did not significantly differ from controls using either TRACULA or TBSS. Multiple regression showed FA of the ATR as predicting chronic mania (p = .0005) and the cingulum-angular bundle as predicting recent mania (p = .02) in patients. TBSS showed chronic mania correlating with FA voxels within the left ATR and corpus callosum.

Conclusions

White matter abnormality in SZ varies in severity across different white matter tract regions. Our results indicate that voxel-based analysis of diffusion data is more sensitive than tract-based analysis in identifying such abnormalities. Absence of white matter abnormality in BD may be related to medication effects and age.

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Our study investigated white matter integrity in 87 young schizophrenia, bipolar disorder and control subjects with a tract-based (TRACULA) and a voxel-based (TBSS) approach, using high-definition diffusion imaging data obtained from the Human Connectome Project ‘Connectom’ scanner.

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TRACULA evaluated fractional anisotropy (FA) from 18 white matter tracts. TBSS evaluated regional white matter FA.

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TRACULA identified a trend towards lower tract FA in schizophrenia subjects across multiple tracts. TBSS results showed mainly unilaterally decreased FA voxels in schizophrenia subjects. FA in bipolar patients did not significantly differ from controls with either method.

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With TRACULA, multiple regression showed that anterior thalamic radiation FA predicted chronic affectivity and cingulum-angular bundle FA predicted recent mania in patients. With TBSS, chronic mania correlated with FA voxels within the left anterior thalamic radiation and corpus callosum.

A comparative study of psychotic and affective symptoms in Rwandan and Kenyan students

AIMS

War and conflict are known to adversely affect mental health, although their effects on risk symptoms for psychosis development in youth in various parts of the world are unclear. The Rwandan genocide of 1994 and Civil War had widespread effects on the population. Despite this, there has been no significant research on psychosis risk in Rwanda. Our goal in the present study was to investigate the potential effects of genocide and war in two ways: by comparing Rwandan youth born before and after the genocide; and by comparing Rwandan and Kenyan adolescents of similar age.

METHODS

A total of 2255 Rwandan students and 2800 Kenyan students were administered the Washington Early Recognition Center Affectivity and Psychosis (WERCAP) Screen. Prevalence, frequency and functional impairment related to affective and psychosis-risk symptoms were compared across groups using univariate and multivariate statistics.

RESULTS

Rwandan students born before the end of the genocide and war in 1994 experienced higher psychotic and affective symptom load (p's < 0.001) with more functional impairment compared with younger Rwandans. 5.35% of older Rwandan students met threshold for clinical high-risk of psychosis by the WERCAP Screen compared with 3.19% of younger Rwandans (χ 2 = 5.36; p = 0.02). Symptom severity comparisons showed significant (p < 0.001) group effects between Rwandan and Kenyan secondary school students on affective and psychotic symptom domains with Rwandans having higher symptom burden compared with Kenyans. Rwandan female students also had higher rates of psychotic symptoms compared with their male counterparts - a unique finding not observed in the Kenyan sample.

CONCLUSIONS

These results suggest extreme conflict and disruption to country from genocide and war can influence the presence and severity of psychopathology in youth decades after initial traumatic events.

Prediction of conversion to psychosis in individuals with an at-risk mental state: a brief update on recent developments

PURPOSE OF REVIEW

So far, only little more than one-third of individuals classified as being at-risk for psychosis have been shown to actually convert to frank psychosis during follow-up. There have therefore been enormous efforts to improve the accuracy of predicting this transition. We reviewed the most recent studies in the field with the aim to clarify whether accuracy of prediction has been improved by the different research endeavors and what could be done to further improve it, and/or what alternative goals research should pursue.

RECENT FINDINGS

A total of 56 studies published between May 2015 and December 2016 were included, of which eight were meta-analyses. New meta-analytical evidence confirms that established instruments for checking clinical risk criteria have an excellent clinical utility in individuals referred to high-risk services. Within a such identified group of ultra-high-risk (UHR) individuals, especially Brief Limited Intermittent Psychotic Symptoms and Attenuated Psychotic Symptoms seem to predict transition. Further assessments should be performed within the UHR individuals, as risk of transition seems particularly high in those with an even higher severity of certain symptoms such as suspiciousness or anhedonia, in those with lower global or social functioning, poor neurocognitive performance or cannabis abuse. Also, electroencephalography, neuroimaging and blood biomarkers might contribute to improving individual prediction. The most promising approach certainly is a staged multidomain assessment. Risk calculators to integrate all data for an individualized prediction are being developed.

SUMMARY

Prediction of psychosis is already possible with an excellent prognostic performance based on clinical assessments. Recent studies show that this accuracy can be further improved by using multidomain approaches and modern statistics for individualized prediction. The challenge now is the translation into the clinic with a broad clinical implementation.

Functional Connectivity of Cognitive Brain Networks in Schizophrenia during a Working Memory Task

Task-based connectivity studies facilitate the understanding of how the brain functions during cognition, which is commonly impaired in schizophrenia (SZ). Our aim was to investigate functional connectivity during a working memory task in SZ. We hypothesized that the task-negative (default mode) network and the cognitive control (frontoparietal) network would show dysconnectivity. Twenty-five SZ patient and 31 healthy control scans were collected using the customized 3T Siemens Skyra MRI scanner, previously used to collect data for the Human Connectome Project. Blood oxygen level dependent signal during the 0-back and 2-back conditions were extracted within a network-based parcelation scheme. Average functional connectivity was assessed within five brain networks: frontoparietal (FPN), default mode (DMN), cingulo-opercular (CON), dorsal attention (DAN), and ventral attention network; as well as between the DMN or FPN and other networks. For within-FPN connectivity, there was a significant interaction between n-back condition and group (p = 0.015), with decreased connectivity at 0-back in SZ subjects compared to controls. FPN-to-DMN connectivity also showed a significant condition × group effect (p = 0.003), with decreased connectivity at 0-back in SZ. Across groups, connectivity within the CON and DAN were increased during the 2-back condition, while DMN connectivity with either CON or DAN were decreased during the 2-back condition. Our findings support the role of the FPN, CON, and DAN in working memory and indicate that the pattern of FPN functional connectivity differs between SZ patients and control subjects during the course of a working memory task.