Increased prevalence of psychopathy and childhood trauma in homicide offenders with schizophrenia compared to nonviolent individuals with schizophrenia.

Purpose: Schizophrenia is associated with an increased homicide risk. Personality pathology, particularly antisocial personality disorder and psychopathic traits, has been associated with increased violence risk in schizophrenia. Childhood trauma, more specifically physical abuse, has been associated with violence risk in healthy populations and in individuals with mental illness. It is, however, unclear how childhood trauma relates to homicide in schizophrenia. This is, to our knowledge, the first study to concurrently examine personality pathology and childhood trauma in a group consisting solely of homicide offenders with schizophrenia (HOS). HOS is compared to nonviolent participants with the same diagnosis (non-HOS). Additionally, currently assessed demographical and clinical characteristics of a Norwegian sample of HOS are reported. Materials and methods: Two groups of participants with schizophrenia were recruited in collaboration with in and outpatient clinics across Norway, HOS (n= 26) and non-HOS (n= 28). Assessments of personality pathology and childhood trauma were conducted, and information about clinical and demographical characteristics was registered. Results: HOS participants had significantly higher psychopathy scores, and more frequently reported moderate to severe childhood physical abuse than non-HOS participants. When simultaneously added to a logistic regression model, only psychopathy uniquely contributed to explaining group membership. Conclusions: Psychopathy and physical abuse was more prevalent among HOS participants compared to non-HOS, but only psychopathy independently predicted homicidal status. These results confirm the importance of including an evaluation of psychopathic traits in violence risk assessments of individuals with schizophrenia.

Large social cognitive impairments characterize homicide offenders with schizophrenia.

Schizophrenia is associated with an increased violence risk, particularly homicide. One possible, but scarcely explored, contributor to the increased violence risk is social cognitive impairment. Individuals with schizophrenia show impairments in social cognition that are associated with poor functional outcome. This study examined social cognition among homicide offenders with schizophrenia (HOS), applying validated measures of emotion perception and theory of mind (ToM). Two groups of individuals with schizophrenia were compared, one had committed homicide (HOS, n = 26), and the other had no violence history (non-HOS, n = 28). Healthy controls (HC, n = 71) were included as reference group for one measure. Emotion perception was indexed by the Emotion in Biological Motion (Emotion) and Pictures of Facial Affect (PFA) tests. ToM was assessed with the Hinting Task and Movie for the Assessment of Social Cognition (MASC). The results showed that HOS participants had significantly poorer performance than non-HOS in both emotion perception and ToM. For the MASC test, HOS participants showed large deficits compared to HC (-4 standard deviations). Particularly, HOS participants made a substantial number of undermentalizing errors. The results suggest that emotion perception deficits and a tendency to undermentalize may be important for understanding homicide in schizophrenia.

Impaired neuropsychological profile in homicide offenders with schizophrenia.

BACKGROUND: Our ability to predict and prevent homicides committed by individuals with schizophrenia is limited. Cognitive impairments are associated with poorer functional outcome in schizophrenia, possibly also homicide. The aim of the current study was to investigate global and specific cognition among homicide offenders with schizophrenia (HOS). METHODS: Twenty-six HOS were compared to 28 individuals with schizophrenia and no history of violence (non-HOS), and a group of healthy controls (HC, n = 151). HOS and non-HOS participants were recruited from in- and outpatient units across Norway. An extensive neuropsychological test battery was administered. RESULTS: HOS participants performed significantly weaker than HC in all cognitive domains. Further, statistically significant differences between HOS and non-HOS participants were found for IQ (d = 0.52) and verbal learning (d = 0.82), with larger impairments in the HOS compared to the non-HOS group. CONCLUSIONS: Our results indicate that HOS participants show clinically significant impairments in global and specific cognition.

Body language reading of emotion in schizophrenia: Associations with symptoms and functional outcome.

Our aim was to explore how body language reading of emotion relates to neurocognition, symptoms and functional outcome in schizophrenia. Fifty-four individuals with schizophrenia and eighty-four healthy controls participated in the study. Emotion perception was assessed with a point-light display (PLD) task, the Emotion in Biological Motion (EmoBio) test, neurocognition was measured with the MATRICS Consensus Cognitive Battery (MCCB), and functioning was indexed by one measure of functional capacity and by one self-report questionnaire. Clinical symptoms were assessed with a five factor Positive and Negative Syndrome Scale (PANSS) symptoms model. Participants with schizophrenia had impaired body language reading of emotions compared to healthy controls (Cohen's d = 0.69). In participants with schizophrenia, emotion perception was associated with neurocognition (r = 0.42), functional capacity (r = 0.27) and disorganization symptoms (r = -0.27). Mediation analyses showed that disorganization symptoms mediated the effects of emotion perception and neurocognition, respectively, on social functional capacity. These results suggest that in individuals with schizophrenia, reduced emotion perception from body movements has negative consequences for functional outcome, but that the effect is mediated through disorganization symptoms.