DSM-IV "criterion A" schizophrenia symptoms across ethnically different populations: evidence for differing psychotic symptom content or structural organization?

Psychosis screening questionnaire: Exploring its factor structure among South African adults

Background

Early detection of psychosis improves treatment outcomes, but there is limited research evaluating the validity of psychosis screening instruments, particularly in low-resourced countries.

Aim

This study aims to assess the construct validity and psychometric properties of the psychosis screening questionnaire (PSQ) in South Africa.

Setting

This study was conducted at several health centres in the Western and Eastern Cape provinces in South Africa.

Methods

The sample consisted of 2591 South African adults participating as controls in a multi-country case-control study of psychiatric genetics. Using confirmatory factor analysis and item response theory, we evaluated the psychometric properties of the PSQ.

Results

Approximately 11% of the participants endorsed at least one psychotic experience on the PSQ, and almost half of them (49%) occurred within the last 12 months. A unidimensional model demonstrated good fit (root mean square error of approximation [RMSEA] = 0.023, comparative fit index [CFI] = 0.977 and Tucker-Lewis Index [TLI] = 0.954). The mania item had the weakest association with a single latent factor (standardised factor loading = 0.14). Model fit improved after removing the mania item (RMSEA = 0.025, CFI = 0.991 and TLI = 0.972). With item response theory analysis, the PSQ provided more information at higher latent trait levels.

Conclusion

Consistent with prior literature, the PSQ demonstrated a unidimensional factor structure among South Africans. In our study, the PSQ in screening for psychosis performed better without the mania item, but future criterion validity studies are warranted.

Contribution

This study highlights that PSQ can be used to screen for early psychosis.

The role of culture on the phenomenology of hallucinations and delusions, explanatory models, and help-seeking attitudes: A narrative review

AIM

Culture has been posited to be involved in the formation and maintenance of delusions and hallucinations. The extent of these differences and how they affect explanatory models of psychosis and help-seeking attitudes remains to be understood. This review aims to present a cultural formulation to account for psychosis onset, symptom maintenance, and help-seeking attitudes.

METHODS

A narrative review was conducted to summarize the existing evidence base regarding cross-cultural differences in hallucinatory and delusional prevalence, explanatory models, and help-seeking attitudes in First Episode Psychosis (FEP) and Non-FEP Schizophrenia samples.

RESULTS

Sixteen studies were eligible for inclusion. In terms of positive symptom specificity, cross-cultural differences were found. Specifically, auditory and visual hallucinations occurred most frequently in African patients, persecutory and grandiose delusions occurred at higher rates in African, Pakistani, and Latino patients, while delusions of reference were most prevalent in White-British groups. Three explanatory models were identified. Westerners tended to endorse a bio-psychosocial explanation, which was associated with increased help-seeking, engagement, and positive medication attitudes. Asian, Latino, Polish, and Māori patients endorsed religious-spiritual explanatory models, while African patients opted for a bewitchment model. The religious-spiritual and bewitchment models were associated with a longer duration of untreated psychosis (DUP) and poorer engagement with mental health services.

CONCLUSIONS

These findings highlight the important influence of culture in the formation and maintenance of positive symptoms of psychosis, engagement, and help-seeking attitudes across different ethnic groups. The incorporation of cultural beliefs in formulation development could facilitate enriched CBTp practices and improved engagement amongst different cultural groups with Early Intervention Services.

The heterogeneity of attenuated and brief limited psychotic symptoms: association of contents with age, sex, country, religion, comorbidities, and functioning

Introduction

The Attenuated Psychosis Symptoms (APS) syndrome mostly represents the ultra-high-risk state of psychosis but, as does the Brief Intermittent Psychotic Symptoms (BIPS) syndrome, shows a large variance in conversion rates. This may be due to the heterogeneity of APS/BIPS that may be related to the effects of culture, sex, age, and other psychiatric morbidities. Thus, we investigated the different thematic contents of APS and their association with sex, age, country, religion, comorbidity, and functioning to gain a better understanding of the psychosis-risk syndrome.

Method

A sample of 232 clinical high-risk subjects according to the ultra-high risk and basic symptom criteria was recruited as part of a European study conducted in Germany, Italy, Switzerland, and Finland. Case vignettes, originally used for supervision of inclusion criteria, were investigated for APS/BIPS contents, which were compared for sex, age, country, religion, functioning, and comorbidities using chi-squared tests and regression analyses.

Result

We extracted 109 different contents, mainly of APS (96.8%): 63 delusional, 29 hallucinatory, and 17 speech-disorganized contents. Only 20 contents (18.3%) were present in at least 5% of the sample, with paranoid and referential ideas being the most frequent. Thirty-one (28.5%) contents, in particular, bizarre ideas and perceptual abnormalities, demonstrated an association with age, country, comorbidity, or functioning, with regression models of country and obsessive-compulsive disorders explaining most of the variance: 55.8 and 38.3%, respectively. Contents did not differ between religious groups.

Conclusion

Psychosis-risk patients report a wide range of different contents of APS/BIPS, underlining the psychopathological heterogeneity of this group but also revealing a potential core set of contents. Compared to earlier reports on North-American samples, our maximum prevalence rates of contents were considerably lower; this likely being related to a stricter rating of APS/BIPS and cultural influences, in particular, higher schizotypy reported in North-America. The various associations of some APS/BIPS contents with country, age, comorbidities, and functioning might moderate their clinical severity and, consequently, the related risk for psychosis and/or persistent functional disability.

Prevalence and risk factors of self-reported psychotic experiences among high school and college students: A systematic review, meta-analysis, and meta-regression

BACKGROUND

Adolescents are at high risk of incident psychopathology. Fleeting psychotic experiences (PEs) that emerge in young people in response to stress may be warning signs that are missed by research that fails to study stressed populations, such as late high school and college/university students. Our aim in this systematic review was to conduct a meta-analysis that estimates prevalence rates of PEs in students, and to assess whether these rates differ by gender, age, culture, and COVID-19 exposure.

METHOD

We searched nine electronic databases, from their inception until January 31, 2022 for relevant studies. We pooled the estimates using the DerSimonian-Laird technique and random-effects meta-analysis. Our main outcome was the prevalence of self-reported PEs in high school and college/university students. We subsequently analyzed our data by age, gender, population, country, culture, evaluation tool, and COVID-19 exposure.

RESULTS

Out of 486 studies retrieved, a total of 59 independent studies met inclusion criteria reporting 210' 024 students from 21 different countries. Nearly one in four students (23.31%; 95% CI 18.41%-29.05%), reported having experienced PEs (heterogeneity [Q = 22,698.23 (62), p = 0.001] τ²  = 1.4418 [1.0415-2.1391], τ = 1.2007 [1.0205-1.4626], I²  = 99.7%, H = 19.13 [18.59-19.69]). The 95% prediction intervals were 04.01%-68.85%. Subgroup analyses showed that the pooled prevalence differed significantly by population, culture, and COVID-19 exposure.

CONCLUSION

This meta-analysis revealed high prevalence rates of self-reported PEs among teen and young adult students, which may have significance for mental health screening in school settings. An important realization is that PEs may have very different mental health meaning in different cultures.

Factor structure and item response of psychosis symptoms among Kenyan adults

BACKGROUND

The aim of this study was to evaluate the construct validity of the psychosis module of the Mini International Neuropsychiatric Interview version 7.0.2 (MINI-7).

METHOD

We utilized data collected from 2738 participants with a primary psychotic or bipolar disorder. Participants were drawn from two Kenyan sites of a large multi-center neuropsychiatric genetic study. The factor structure of the MINI-7 psychosis items were explored using confirmatory factor analyses (CFA) and Item Response Theory approach, for the full sample and by gender.

RESULTS

The CFA revealed that a 1-factor model provided adequate fit for the MINI-7 psychosis items for the full sample (x2 = 397.92, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.92; TLI = 0.90) as well as for the female (x2 = 185.16.92, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.93; TLI = 0.91) and male groups (x2 = 242.09, df = 35, p < .0001; RMSEA = 0.06; CFI = 0.92; TLI = 0.89). Item thresholds for the full sample, and female and male groups were highest for 'odd beliefs' (-1.42, -1.33, and -1.51 respectively) and lowest for 'visual hallucinations' (-0.03, -0.04, and -0.01 respectively).

LIMITATIONS

Our study used a hospital-based population, which may have excluded patients with milder psychotic symptoms. Findings may therefore not be generalizable to the community setting.

CONCLUSIONS

Our findings indicate good construct validity of the MINI-7 psychosis module, and provides support for use of the tool in diagnosing psychotic disorders in clinical settings in Kenya.

Validity, reliability and clinical utility of mental disorders: The case of ICD-11 schizophrenia

Diagnostic classification systems categorise mental psychopathology in mental disorders. Although these entities are clinical constructs developed by consensus, it has been pointed out that in practice they are usually managed as natural entities and without evaluating aspects related to their nosological construction. The objectives of the study are to review a) the conceptualisation of mental disorders, b) the indicators of validity, reliability and clinical utility, and c) the values ​​of these indicators in ICD-11 schizophrenia. The results show that mental disorders are conceptualised as discrete entities, like the diseases of other areas of medicine; however, differences are observed between these diagnostic categories in clinical practice. The reliability and clinical utility of mental disorders are adequate; however, the validity is not yet clarified. Similarly, ICD-11 schizophrenia demonstrates adequate reliability and clinical utility, but its validity remains uncertain. The conceptualisation of psychopathology in discrete entities may be inadequate for its study, therefore dimensional and mixed models have been proposed. The indicators of validity, reliability and clinical utility enable us to obtain an accurate view of the nosological state of mental disorders when evaluating different aspects of their nosological construction.

Psychotic like experiences among Nigerian school adolescents: Findings from the Lagos Schools Emotional and Behavioral Health Survey

AIM

This study aimed to explore the presence of psychotic like experience (PLE) symptoms and evaluate for the possible socio-demographic, family, school and mental health variables associated with clinically significant PLE symptoms in Nigeria school adolescent.

METHODS

A total of 9441 adolescents from 47 secondary schools in Lagos Nigeria completed questionnaire detailing sociodemographic, family and school related variables. Mental health was assessed with the Mini International Diagnostic Interview for children and adolescents (MINI-KID). PLE was assessed using the 16-item version of Prodromal Questionnaire (PQ-16).

RESULTS

The mean age in years was 15.6 (SD 1.5) and 50.4% were females. The mean PQ-16 score was 2.18 (SD 2.38) with 95% CI 2-15-2.21. A total of 2878 (30.5%) adolescents had no PLE symptoms while 990 (10.5%) had clinically significant PLE symptoms. The most experienced symptoms were "déjà vu" (35.5%) and loss of interest (29.6%). The variables independently associated with clinically significant PLE symptoms were "having no close friend in school" (OR 2.66, 95% CI 2.08-3.41), "often beaten by parents" (OR 1.98, 95% CI 1.67-2.34) "from a polygamous family" (OR 1.80, 95% CI 1.49-2.18), and "diagnosis of depression" (OR 1.33, 95% CI 1.09-1.63).

CONCLUSION

We have shown that PLE symptoms are relatively common in non-help seeking Nigerian school adolescents and that personal and family factors are significantly associated. Longitudinal studies will be needed to chart the path of symptoms and determinants of distress, help seeking and development of psychosis.

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.

Validity, Reliability and Clinical Utility of Mental Disorders: The Case of ICD-11 Schizophrenia

Diagnostic classification systems categorise mental psychopathology in mental disorders. Although these entities are clinical constructs developed by consensus, it has been pointed out that in practice they are usually managed as natural entities and without evaluating aspects related to their nosological construction. The objectives of the study are to review a) the conceptualisation of mental disorders, b) the indicators of validity, reliability and clinical utility, and c) the values of these indicators in ICD-11 schizophrenia. The results show that mental disorders are conceptualised as discrete entities, like the diseases of other areas of medicine; however, differences are observed between these diagnostic categories in clinical practice. The reliability and clinical utility of mental disorders are adequate; however, the validity is not yet clarified. Similarly, ICD-11 schizophrenia demonstrates adequate reliability and clinical utility, but its validity remains uncertain. The conceptualisation of psychopathology in discrete entities may be inadequate for its study, therefore dimensional and mixed models have been proposed. The indicators of validity, reliability and clinical utility enable us to obtain an accurate view of the nosological state of mental disorders when evaluating different aspects of their nosological construction.

Association between paternal age and risk of schizophrenia: a nationwide population-based study

PURPOSE

To study the association between paternal age and schizophrenia in offspring.

METHODS

This report describes a nationwide population-based cohort study from 1997 to 2013. Data from Taiwan's National Health Insurance Research Database were utilized to answer the research question. A total of 17,649 offspring with schizophrenia were selected from 11 million offspring in the general population. Additionally, we established the offspring without schizophrenia as the comparison group by matching the study cohort by age, gender in a 1:4 ratio (n = 70,596).

RESULTS

The median age at first presentation with schizophrenia was 20 years (interquartile range (IQR), 17 to 24). Comparison of the schizophrenia and non-schizophrenia groups indicated that father's age at birth (30.0 (IQR), 27 to 33 vs. 29.0 (IQR), 26 to 32 years), mother's age at birth (26.0 (IQR), 24 to 29 vs. 26.0 (IQR), 23 to 29 years), paternal schizophrenia (2.6% vs. 0.6%), and maternal schizophrenia (4.4% vs. 0.7%) were all significantly greater in the schizophrenia group. In addition, each 5-year increase in father's age increased the odds of being diagnosed with schizophrenia (model 1: aOR = 1.22; 95% CI 1.20, 1.24; model 2: aOR = 1.20; 95% CI 1.18, 1.23). Subgroup analysis showed that each 5-year increase in father's age increased the odds of being diagnosed with schizophrenia in male and female offspring, as well as in offspring of mothers and fathers with or without schizophrenia (aOR = 1.20 to 2.20, all p values < 0.01).

CONCLUSION

This study indicated that advanced paternal age increased the risk of schizophrenia in offspring. Offspring born to fathers older by 5-year increments were at heightened risk of schizophrenia.

Prevalence and Correlates of Psychotic Like Experiences in a Large Community Sample of Young Adults in Tunisia

Despite the increased focus on non-clinical psychosis populations, no community surveys have properly investigated the phenotypal expression of Psychotic like experiences (PLEs) in the Arab-Muslim world. We aimed to examine the prevalence and correlates of PLEs in a large sample of Tunisian college students. A total of 1489 students (64.3% female, aged 18-40) participated in a cross-sectional survey. The Positive Subscale of Community Assessment of Psychotic Experiences was used to measure PLEs. The rates of PLEs found in our work were relatively high compared with those found in previous international studies, with 51.4% of the participants reporting at least one positive PLE 'nearly-always'. After controling for confounding variables, other drug use in the past year represented the only substance use variable among the significant predictors in the final model. Our findings should raise awareness of the need for implementing an early intervention programs in our region.

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.

Mental Health Service Provision in Low- and Middle-Income Countries

This article discusses the provision of mental health services in low- and middle-income countries (LMICs) with a view to understanding the cultural dynamics-how the challenges they pose can be addressed and the opportunities harnessed in specific cultural contexts. The article highlights the need for prioritisation of mental health services by incorporating local population and cultural needs. This can be achieved only through political will and strengthened legislation, improved resource allocation and strategic organisation, integrated packages of care underpinned by professional communication and training, and involvement of patients, informal carers, and the wider community in a therapeutic capacity.

Asian Indians in America: The influence of values and culture on mental health

Asian Indians represent a significant portion of the largest growing race of Asians in the past decade in the United States. This selective review examines major cultural themes related to first- and second-generation Asian Indians living in the United States as they impact psychological and psychiatric dysfunction in this population. Specifically, we review the impact of Asian Indian culture on mental health, discuss the impact of acculturation and ethnic identity development on the mental health of Indian-Americans, and focus on typical mental health problems of Asian Indian adolescents, women and elderly in America. Finally, we provide a brief overview of empirically-supported treatment approaches and cultural considerations for additional treatments relevant to this population. This review is intended to provide an important foundation for more systematic empirically-driven investigation into better understanding how Asian Indian cultural themes impact mental health for Indian-Americans, and how to develop effective treatments for these issues in this cultural group.

How culture shapes social cognition deficits in mental disorders: A review

Social cognitive skills are indispensable for successful communication with others. Substantial research has determined deficits in these abilities in patients with mental disorders. In neurobiological development and continuing into adulthood, cross-cultural differences in social cognition have been demonstrated. Moreover, symptomatic patterns in mental disorders may vary according to the cultural background of an individual. Cross-cultural studies can thus help in understanding underlying (biological) mechanisms and factors that influence behavior in health and disease. In addition, studies that apply novel paradigms assessing the impact of culture on cognition may benefit and advance neuroscience research. In this review, the authors give an overview of cross-cultural research in the field of social cognition in health and in mental disorders and provide an outlook on future research directions, taking a neuroscience perspective.