Repetitive and non-repetitive violent offending behaviour in male patients in a maximum security mental hospital - Clinical and neuroimaging findings

Objective: To examine if different violent offending behaviours are associated with different clinical and neuroimaging profiles. Method: Thirty-nine schizophrenic and schizoaffective offenders from a maximum security mental hospital - 20 repetitive violent offenders (RVOs) and 19 non-repetitive violent offenders (NRVOs) - were selected for clinical and neuroimaging assessments. Results: Both groups had positive family history of mental illness and violence. Age, diagnosis, duration of illness, victim profiles and use of weapons at the time of the index offence were similar. RVOs had a higher prevalence of early parental separation, juvenile conduct problem, previous convictions of crimes not involving violence, impulsive suicide attempts, delusion of their lives being threatened at the time of the index offence and electroencephalographic (EEG) abnormalities localized to temporal lobes. NRVOs had a higher prevalence of sexual inexperience and command hallucinations to kill at the time of the index offence. Asymmetric gyral patterns at the temporo-parietal region were particularly common in RVOs and absent in NRVOs. Non-specific white matter changes in magnetic resonance imaging (MRI) and generalized cortical hypometabolism in positron emission tomography (PET) were present in both groups. Conclusions: Different structural and metabolic changes in the brain were associated with different violent offending behaviours. The complex interaction between violent behaviour, clinical features and neuroimaging findings in schizophrenia requires further studies.