Cognition and violent behavior in psychotic disorders: A nationwide case-control study

Violent Offending in Males With or Without Schizophrenia: A Role for Social Cognition?

BACKGROUND AND HYPOTHESIS

Reduced social cognition has been reported in individuals who have committed interpersonal violence. It is unclear if individuals with schizophrenia and a history of violence have larger impairments than violent individuals without psychosis and non-violent individuals with schizophrenia. We examined social cognition in two groups with violent offenses, comparing their performance to non-violent individuals with schizophrenia and healthy controls.

STUDY DESIGN

Two social cognitive domains were assessed in four groups: men with a schizophrenia spectrum disorder with (SSD-V, n = 27) or without (SSD-NV, n = 42) a history of violence, incarcerated men serving preventive detention sentences (V, n = 22), and healthy male controls (HC, n = 76). Theory of mind (ToM) was measured with the Movie for the Assessment of Social Cognition (MASC), body emotion perception with Emotion in Biological Motion (EmoBio) test.

STUDY RESULTS

Kruskal-Wallis H-tests revealed overall group differences for social cognition. SSD-V had a global and clinically significant social cognitive impairment. V had a specific impairment, for ToM. Binary logistic regressions predicting violence category membership from social cognition and psychosis (SSD status) were conducted. The model with best fit, explaining 18%-25% of the variance, had ToM as the only predictor.

CONCLUSIONS

Social cognitive impairment was present in individuals with a history of violence, with larger and more widespread impairment seen in schizophrenia. ToM predicted violence category membership, psychosis did not. The results suggest a role for social cognition in understanding interpersonal violence.

Structural brain abnormalities and aggressive behaviour in schizophrenia: Mega-analysis of data from 2095 patients and 2861 healthy controls via the ENIGMA consortium

Background

Schizophrenia is associated with an increased risk of aggressive behaviour, which may partly be explained by illness-related changes in brain structure. However, previous studies have been limited by group-level analyses, small and selective samples of inpatients and long time lags between exposure and outcome.

Methods

This cross-sectional study pooled data from 20 sites participating in the international ENIGMA-Schizophrenia Working Group. Sites acquired T1-weighted and diffusion-weighted magnetic resonance imaging scans in a total of 2095 patients with schizophrenia and 2861 healthy controls. Measures of grey matter volume and white matter microstructural integrity were extracted from the scans using harmonised protocols. For each measure, normative modelling was used to calculate how much patients deviated (in z-scores) from healthy controls at the individual level. Ordinal regression models were used to estimate the associations of these deviations with concurrent aggressive behaviour (as odds ratios [ORs] with 99% confidence intervals [CIs]). Mediation analyses were performed for positive symptoms (i.e., delusions, hallucinations and disorganised thinking), impulse control and illness insight. Aggression and potential mediators were assessed with the Positive and Negative Syndrome Scale, Scale for the Assessment of Positive Symptoms or Brief Psychiatric Rating Scale.

Results

Aggressive behaviour was significantly associated with reductions in total cortical volume (OR [99% CI] = 0.88 [0.78, 0.98], p = .003) and global white matter integrity (OR [99% CI] = 0.72 [0.59, 0.88], p = 3.50 × 10-5) and additional reductions in dorsolateral prefrontal cortex volume (OR [99% CI] = 0.85 [0.74, 0.97], p =.002), inferior parietal lobule volume (OR [99% CI] = 0.76 [0.66, 0.87], p = 2.20 × 10-7) and internal capsule integrity (OR [99% CI] = 0.76 [0.63, 0.92], p = 2.90 × 10-4). Except for inferior parietal lobule volume, these associations were largely mediated by increased severity of positive symptoms and reduced impulse control.

Conclusions

This study provides evidence that the co-occurrence of positive symptoms, poor impulse control and aggressive behaviour in schizophrenia has a neurobiological basis, which may inform the development of therapeutic interventions.

Research on interpersonal violence in schizophrenia: based on different victim types

BACKGROUND

Schizophrenia is one of the most common severe mental disorders associated with an increased risk of violence. The present study compares the demographical, clinical, and criminological characteristics of the patients with schizophrenia who committed different types of violence to relatives, acquaintances, or strangers.

METHOD

Archives of the violent offenders with schizophrenia referred to forensic psychiatric assessments from January 2015 to December 2019 in the West China Forensic Medicine Assessment Center in China were analyzed. The demographic information, mental illness history, and criminological characteristics of the offenders were collected. The clinical symptoms, previous violent behaviors, and social deficits were also evaluated. One-way ANOVA, Kruskal-Wallis test, Chi-square test, and logistic regression analysis were enrolled to do the statistical analysis.

RESULTS

The study enrolled 332 cases: 165 cases (49.7%) in the acquaintance victim group (AV), 96 cases (28.9%) in the relative victim group (RV), and 71 cases (21.4%) in the stranger victim group (SV). The multinomial logistic regression analysis revealed that older patients were less likely to attack relatives (OR = 0.966, 95% CI = 0.944-0.990; p = 0.005), and strangers, (OR = 0.971, 95% CI = 0.944-0.998; p = 0.034). Patients who lived with others were more inclined to attack relatives (OR = 15.057, 95% CI = 3.508-64.628; p < 0.001). Additionally, employed patients were more likely to attack strangers (OR = 2.034, 95% CI = 1.036-3.994; p = 0.039). The regression equation did not include psychiatric symptoms. For RV and AV victims, the risk of death was higher compared to that of SV victims (OR = 13.778, p < 0.001; OR = 2.663, p = 0.014).

CONCLUSION

In the interpersonal violence cases committed by schizophrenia patients, the victim type correlates with demographic characteristics of offenders such as living situation, age, and employment status, but not with the psychiatric symptoms. The majority of victims were acquaintances and relatives, and the relative victims having more severe injuries. In order to decrease interpersonal violence, especially violent crimes, more people, especially family members and neighbors, should be educated about symptoms of schizophrenia, the ways to communicate with the patients, and the methods for crisis management.

Processing of Spoken Emotions in Schizophrenia: Forensic and Non-forensic Patients Differ in Emotional Identification and Integration but Not in Selective Attention

Patients with schizophrenia (PwS) typically demonstrate deficits in visual processing of emotions. Less is known about auditory processing of spoken-emotions, as conveyed by the prosodic (tone) and semantics (words) channels. In a previous study, forensic PwS (who committed violent offenses) identified spoken-emotions and integrated the emotional information from both channels similarly to controls. However, their performance indicated larger failures of selective-attention, and lower discrimination between spoken-emotions, than controls. Given that forensic schizophrenia represents a special subgroup, the current study compared forensic and non-forensic PwS. Forty-five PwS listened to sentences conveying four basic emotions presented in semantic or prosodic channels, in different combinations. They were asked to rate how much they agreed that the sentences conveyed a predefined emotion, focusing on one channel or on the sentence as a whole. Their performance was compared to that of 21 forensic PwS (previous study). The two groups did not differ in selective-attention. However, better emotional identification and discrimination, as well as better channel integration were found for the forensic PwS. Results have several clinical implications: difficulties in spoken-emotions processing might not necessarily relate to schizophrenia; attentional deficits might not be a risk factor for aggression in schizophrenia; and forensic schizophrenia might have unique characteristics as related to spoken-emotions processing (motivation, stimulation).

The Effects of Cognitive Behavior Therapy and Social Skill Training among Schizophrenia with Risk of Violent Behavior

BACKGROUND: Schizophrenia is a condition in which people suffer from impaired ability to think, perceive, and show emotional responses and interact socially. Patients with schizophrenia can experience the risk of violent behavior (RVB). Psychotherapy is needed to deal with the problem. AIM: This study aimed to investigate the effects of cognitive behavior therapy (CBT) and social skill training (SST) on signs and symptoms of risks of violent behavior (RVB). METHODOLOGY: This study employed a quasi-experimental without a control group. The research samples used purposive sampling were 30 patients with symptoms of risks of violent behavior. Meanwhile, the measurement used the sign and symptom questioners of risks of violent behavior (Z = 0.791). RESULT: This study revealed that signs and symptoms decreased significantly (p < 0.05) from 10.45 to 5.41 after the respondents had obtained the CBT. Moreover, after the respondents had received CBT and SST, the sign and symptoms decreased significantly (p < 0.05) from 5.41 to 0.52. CONCLUSION: This study recommends that the combination of CBT and SST be administered to patients with schizophrenia with risks of violent behavior.

Candidate symptomatic markers for predicting violence in schizophrenia: A cross-sectional study of 7711 patients in a Chinese population

OBJECTIVE

Violent behaviour is an alarming problem among schizophrenia patients. The effects of historical, clinical, and pathological risk factors for violence have been investigated by multiple studies, but consensus has not been achieved. As psychotic symptoms are more direct and intuitive indicators for violence, identifying robustly associated symptoms is a crucial part of the future prediction and precise management of violent patients in clinics. This study aims to identify the psychotic symptoms correlated with violence among schizophrenia patients in a Chinese population.

METHODS

In this cross-sectional study, the medical records of 7711 schizophrenia patients (4711 in the discovery set and 3000 in the validation set) were collected from 1998 to 2010. Their psychotic symptoms were extracted, and the patients were divided into violent and non-violent groups. Multivariate logistic analysis was applied to identify symptoms associated with violence in the discovery set.

RESULTS

Eight psychotic symptoms were found to be significantly correlated with violence in schizophrenia. "Destruction of property", "verbal aggression" and "insomnia" increased the risk of violence, while "flat affect", "delusion of persecution", "auditory hallucination", "vagueness of thought" and "poverty of thought" decreased the risk of violence. The regression model was evaluated by receiver operating characteristic (ROC) analysis for its discriminatory performance, achieving area under curve (AUC) values of 0.887 in the discovery sample set and 0.824 in the validation sample set.

CONCLUSIONS

The correlated symptoms identified by this study can serve as future candidate predictors for violence in schizophrenia, paving the way for precise management of schizophrenia patients in clinics.