Influence of depressive symptoms on distress related to positive psychotic-like experiences in women

Association between tuberculosis and psychotic experiences: Mediating factors and implications for patient care in low- and middle-income countries

Background

Tuberculosis may play a role in the aetiology of psychosis. However, little is known about the association between tuberculosis and psychotic experiences (PEs) or the mediating factors of this association.

Methods

We analysed cross-sectional data from 48 low- and middle-income countries of the World Health Survey (WHS). Tuberculosis assessment was based on past 12-month symptoms of active tuberculosis. We assessed four types of past 12-month PEs with the Composite International Diagnostic Interview. We performed multivariable multinomial logistic regression and mediation analysis.

Results

We analysed data on 224 842 individuals aged ≥18 years (mean age = 38.3 years, standard deviation = 16.0; 50.7% women). Tuberculosis was associated with 1.84 (95% confidence interval (CI) = 1.41-2.40), 2.18 (95%CI = 1.58-3.03), and 3.79 (95%CI = 2.88-4.98) times higher odds for 1, 2, and ≥3 PEs, respectively. The mediation analysis showed that the association between tuberculosis and at least one PE is mainly explained by anxiety (31.5%), sleep/energy (27.8%), and pain/discomfort (23.5%).

Conclusions

Tuberculosis was associated with increased odds of PEs. Factors such as affect, sleep, and pain should be considered in tuberculosis patients to target those who might be particularly vulnerable to PEs, and consequently, to psychotic disorders and other adverse effects of PE.

Resilience buffers the association between psychotic-like experiences and suicide risk: a prospective study from a non-clinical sample

BACKGROUND

Several studies have reported that psychotic-like experiences are associated with low levels of resilience and increased suicide risk. However, it remains unknown as to whether resilience mediates or moderates the association between psychotic-like experiences and suicide risk. Therefore, in this study, we aimed to explore the moderating and mediating effect of resilience in the association between psychotic-like experiences and suicide risk.

METHODS

A total of 1100 non-clinical, young adults (aged 18 - 35 years) with a negative history of psychiatric treatment were enrolled. Participants were recruited by the snowball sampling methodology through advertisements posted in the online platform. They were followed-up for about 7 months. Variables of interest were recorded using self-reports. Psychopathological assessment was conducted using the Prodromal Questionnaire-16, the Patient Health Questionnaire-9, the Generalized Anxiety Disorder-7, the Traumatic Experience Checklist, the Childhood Experience of Care and Abuse Questionnaire, the Cannabis Problems Questionnaire, the Connor-Davidson Resilience Scale-10, and the Mini-International Neuropsychiatric Interview. The STROBE statement guidelines were followed.

RESULTS

The moderation analysis revealed that higher levels of psychotic-like experiences and related distress at baseline were associated with significantly higher suicide risk at the follow-up after adjustment for baseline sociodemographic characteristics, depressive and anxiety symptoms, a history of childhood trauma, and problematic cannabis use. The interaction between follow-up resilience and distress related to baseline psychotic-like experiences was significantly and negatively associated with suicide risk at the follow-up. Specifically, the correlation between the level of distress related to psychotic-like experiences and suicide risk was significant and positive only in participants with lower levels of resilience. This interaction did not reach statistical significance for the baseline level of psychotic-like experiences. No significant mediating effect of the follow-up resilience level in the association between baseline psychotic-like experiences and the follow-up suicide risk was found.

CONCLUSIONS

Findings from the present study indicate that resilience might protect against suicide risk in people with psychotic-like experiences. These findings could be applied in the formulation of early intervention strategies aimed at mitigating the risk of suicide. Future studies need to explore the effects of interventions targeting resilience for individuals with psychotic-like experiences.

White matter, cognition and psychotic-like experiences in UK Biobank

BACKGROUND

Psychotic-like experiences (PLEs) are risk factors for the development of psychiatric conditions like schizophrenia, particularly if associated with distress. As PLEs have been related to alterations in both white matter and cognition, we investigated whether cognition (g-factor and processing speed) mediates the relationship between white matter and PLEs.

METHODS

We investigated two independent samples (6170 and 19 891) from the UK Biobank, through path analysis. For both samples, measures of whole-brain fractional anisotropy (gFA) and mean diffusivity (gMD), as indications of white matter microstructure, were derived from probabilistic tractography. For the smaller sample, variables whole-brain white matter network efficiency and microstructure were also derived from structural connectome data.

RESULTS

The mediation of cognition on the relationships between white matter properties and PLEs was non-significant. However, lower gFA was associated with having PLEs in combination with distress in the full available sample (standardized β = -0.053, p = 0.011). Additionally, lower gFA/higher gMD was associated with lower g-factor (standardized β = 0.049, p < 0.001; standardized β = -0.027, p = 0.003), and partially mediated by processing speed with a proportion mediated of 7% (p = < 0.001) for gFA and 11% (p < 0.001) for gMD.

CONCLUSIONS

We show that lower global white matter microstructure is associated with having PLEs in combination with distress, which suggests a direction of future research that could help clarify how and why individuals progress from subclinical to clinical psychotic symptoms. Furthermore, we replicated that processing speed mediates the relationship between white matter microstructure and g-factor.

Cortical Gyrification, Psychotic-Like Experiences, and Cognitive Performance in Nonclinical Subjects

BACKGROUND

Psychotic-like experiences (PLE) are present in nonclinical populations, yet their association with brain structural variation, especially markers of early neurodevelopment, is poorly understood. We tested the hypothesis that cortical surface gyrification, a putative marker of early brain development, is associated with PLE in healthy subjects.

METHODS

We analyzed gyrification from 3 Tesla MRI scans (using CAT12 software) and PLE (positive, negative, and depressive symptom dimensions derived from the Community Assessment of Psychic Experiences, CAPE) in 103 healthy participants (49 females, mean age 29.13 ± 9.37 years). A subsample of 63 individuals completed tasks from the Wechsler Adult Intelligence Scale and Controlled Oral Word Association Test. Estimated IQ and a composite neuropsychological score were used to explore mediation pathways via cognition.

RESULTS

Positive PLE distress was negatively associated with gyrification of the left precuneus. PLE depression dimension showed a negative association with gyrification in the right supramarginal and temporal region. There was no significant mediating effect of cognition on these associations.

CONCLUSION

Our results support a neurobiological psychosis spectrum, for the first time linking an early developmental imaging marker (rather than volume) to dimensional subclinical psychotic symptoms. While schizophrenia risk, neurodevelopment, and cognitive function might share genetic risk factors, additional mediation analyses did not confirm a mediating effect of cognition on the gyrification-psychopathology correlation.

Don't worry, be happy: Protective factors to buffer against distress associated with psychotic experiences

BACKGROUND

Around 6-7% of the general population report psychotic experiences (PEs). Positive PEs (e.g. hearing voices) may increase the risk of development of psychotic disorder. An important predictor of the transition to a psychotic disorder is secondary distress associated with PEs. We examined the moderating effect of potential protective factors on this secondary distress.

METHODS

Data come from 2870 individuals of the HowNutsAreTheDutch study. PEs were assessed with the Community Assessment of Psychic Experience (CAPE) questionnaire and were divided into three subdomains ("Bizarre experiences", "Delusional ideations", and "Perceptual anomalies"). Protective factors explored were having a partner, having a pet, benevolent types of humor, optimism and the high levels of personality traits emotional stability (reversed neuroticism), extraversion, openness to experience, conscientiousness, and agreeableness. We examined whether these protective factors moderated (lowered) the association between frequency of PEs and PE-associated distress.

RESULTS

Due to low prevalence of perceptual anomalies in the sample, this domain was excluded from analysis. No moderating effects were observed of protective factors on the association between bizarre experiences and distress. Having a partner and high levels of optimism, self-enhancing humor, openness, extraversion and emotional stability moderated the association between delusional ideations and secondary distress, leading to lower levels of distress.

CONCLUSIONS

Several protective factors were found to moderate the association between frequency and secondary distress of delusional ideations, with high levels of the protective factors being associated with lower levels of distress. A focus on protective factors could be relevant for interventions and prevention strategies regarding psychotic phenomena.

The link between self-compassion and psychotic-like experiences: A matter of distress?

OBJECTIVES

Self-shaming and self-criticism have been shown to contribute to the emergence of distressing psychotic symptoms and psychotic-like experiences (PLEs). In contrast, a self-compassionate mindset may protect against negative evaluations in response to PLEs leading to less distress. This study explores the association between self-compassion, the frequency of PLEs, and their associated distress.

DESIGN

The study used a correlational, cross-sectional design on a German community sample.

METHODS

A total of 234 participants completed the self-compassion scale (SCS), the Peters' Delusions Inventory, and a modified version of the Launay-Slade Hallucination Scale that measures frequency and distress of hallucinatory experiences. Pearson correlations between SCS and frequency of PLEs as well as between SCS and PLE-distress were compared. Additionally, network analyses of SCS and PLE-measures were calculated.

RESULTS

Self-compassion was associated with less-frequent PLEs and with less PLE-distress, with stronger correlations between self-compassion and PLE-distress. The network analysis showed the self-compassion facets isolation and overidentification to be the closest links to PLE-distress.

CONCLUSIONS

Self-compassion is associated with less PLE related distress. Prevention programmes and interventions that target the negative facets associated with lack of self-compassion may be promising. However, future studies need to explore the causal role of self-compassion facets in the formation of PLE-distress.

PRACTITIONER POINTS

Low levels of self-compassion are associated with being more distressed by psychotic experiences. As the self-compassion facets isolation and overidentification are most strongly related to distress, prevention and intervention programmes may benefit from focusing on these negative facets.

Cannabis use as a risk factor for psychotic-like experiences: A systematic review of non-clinical populations evaluated with the Community Assessment of Psychic Experiences

AIM

Epidemiological data have provided evidence that psychotic-like experiences (PLEs) can occur in the general population, not necessarily accompanied by the impairment and suffering observed in formal psychiatric diagnoses. According to the psychosis continuum hypothesis, PLEs would be subject to the same risk factors as frank psychosis. The aim of this review was to summarize observational studies that evaluated cannabis use as a risk factor for PLEs as determined by the Community Assessment of Psychic Experiences in non-clinical samples. The instrument composed of 3 dimensions-positive, negative and depressive-is a scale specifically designed to assess the occurrence, frequency and impact of PLEs in non-clinical population.

METHODS

We searched PubMed/Medline, Web of Science and PsycInfo electronic databases for indexed peer-reviewed studies published until September 2017.

RESULTS

We initially identified 100 articles. The PRISMA model for systematic reviews was used and 19 full-text articles were analysed. In general, the findings suggested that the higher the cannabis use and the younger the participants, the higher the reports of PLEs, although associations were more consistent for the positive dimension.

CONCLUSIONS

More attention should be paid to the understanding of the risk factors of PLEs in the general population, since these experiences are themselves a risk for psychotic disorders.