Prospective cohort study of the relationship between neuro-cognition, social cognition and violence in forensic patients with schizophrenia and schizoaffective disorder

Abstract

BackgroundThere is a broad literature suggesting that cognitive difficulties are associated with violence across a variety of groups. Although neurocognitive and social cognitive deficits are core features of schizophrenia, evidence of a relationship between cognitive impairments and violence within this patient population has been mixed.MethodsWe prospectively examined whether neurocognition and social cognition predicted inpatient violence amongst patients with schizophrenia and schizoaffective disorder (n = 89; 10 violent) over a 12 month period. Neurocognition and social cognition were assessed using the MATRICS Consensus Cognitive Battery (MCCB).ResultsUsing multivariate analysis neurocognition and social cognition variables could account for 34 % of the variance in violent incidents after controlling for age and gender. Scores on a social cognitive reasoning task (MSCEIT) were significantly lower for the violent compared to nonviolent group and produced the largest effect size. Mediation analysis showed that the relationship between neurocognition and violence was completely mediated by each of the following variables independently: social cognition (MSCEIT), symptoms (PANSS Total Score), social functioning (SOFAS) and violence proneness (HCR-20 Total Score). There was no evidence of a serial pathway between neurocognition and multiple mediators and violence, and only social cognition and violence proneness operated in parallel as significant mediators accounting for 46 % of the variance in violent incidents. There was also no evidence that neurocogniton mediated the relationship between any of these variables and violence.ConclusionsOf all the predictors examined, neurocognition was the only variable whose effects on violence consistently showed evidence of mediation. Neurocognition operates as a distal risk factor mediated through more proximal factors. Social cognition in contrast has a direct effect on violence independent of neurocognition, violence proneness and symptom severity. The neurocognitive impairment experienced by patients with schizophrenia spectrum disorders may create the foundation for the emergence of a range of risk factors for violence including deficits in social reasoning, symptoms, social functioning, and HCR-20 risk items, which in turn are causally related to violence.Electronic supplementary materialThe online version of this article (doi:10.1186/s12888-015-0548-0) contains supplementary material, which is available to authorized users.

Risk factors for inpatient violence and self-harm in forensic psychiatry: the role of head injury, schizophrenia and substance misuse

“…Similarly, the prevalence of individuals who had an episode of inpatient violence was alarmingly high at 42.2%. Assessed violence proneness was just slightly higher than that seen within previous literature [21,62], however, direct comparison of assessed violence proneness using the HCR-20 is difficult due to cross-culture and service variabilities. Nonetheless, these results highlight the startling prevalence of harm to self and others documented within the present sample.…”

“…Schizophrenia is commonly the most prevalent diagnosis in forensic psychiatry inpatients and, while a majority of those diagnosed are not violent, a diagnosis of schizophrenia is now recognised as conferring an increased risk for violence and aggression in comparison to the general population [18][19]. This increased risk has been attributed to symptomology, comorbidities, cognitive abilities and neurobiology [18][19][20][21], highlighting the wide array of underpinning mechanisms. A diagnosis of schizophrenia is also associated with significantly increased risk of self-harm in both men and women, with comorbid substance abuse significantly increasing this risk [22][23].…”

Clinical and neuropsychological features of violence in schizophrenia: A prospective cohort study

“…Contrary to our hypothesis, vSZ patients outperformed controls on executive tasks in a manner that has been found in the past (Lapierre et al, 1995;Rasmussen et al, 1995).…”

“…Current psychopathology, social reasoning and functioning have also been reported to be linked to violence (Serper et al, 2008;O'Reilly et al, 2015), though a recent meta-analysis found that only global cognitive impairment and lack of insight predicted violence in schizophrenia (Reinharth et al, 2014).…”

Moral cognition and homicide amongst forensic patients with schizophrenia and schizoaffective disorder: A cross-sectional cohort study

“…Empirical evidence supports an association between violence and delusions and hallucinations (Coid et al, 2013;Keers et al, 2014;Ullrich et al, 2014) but the form and content of the associated moral reasoning has not been investigated. Understanding whether impaired neurocognitive ability and moral cognition in schizophrenia are associated with serious violence could have implications for risk assessment and treatment (O'Reilly et al, 2015).…”