Treatment of violent mentally ill lowers rates of reoffending. New Study

Important new study: Researchers followed violent offenders (sentenced to 2 years or more) for an average of 10 months following their release and ascertained the rate of violent re-offending. The study included 742 individuals without psychosis; 94 with schizophrenia; 29 with delusional disorder; and 102 with drug-induced psychosis. It also assessed whether the individual’s mental illness was treated in prison, after leaving prison, or not at all.



Those with schizophrenia who were treated (either in prison or after leaving prison) did not have a higher incidence of violent re-offending than did individuals without psychosis. However, those who were not treated were more than 3 times more likely to violently reoffend compared to individuals without psychosis. As summarized by the authors:

“Our findings are consistent with those in studies of treatment compliance in psychosis that report that nonadherence to medication is associated with increased risk of violence….Our results confirm the opinion of most clinicians that treatment reduces the risk of violence among persons with schizophrenia and that the risk of future violence is greatly increased among prisoners with schizophrenia if they are not treated.”

The study has two other noteworthy findings. First, treating the substance abuse did not decrease violent reoffending; it was only the treatment of the psychotic symptoms which decreased the reoffending. Second, the emergence of persecutory delusions was the key symptom which was associated with reoffending; auditory hallucinations, thought insertion, and “strange experiences” by themselves were not related to reoffending. 

This study provides further evidence that evaluating mentally ill prisoners who are being released and connecting them to treatment benefits the individual and society. If the person won't comply with treatment then making a treatment a requirement of probation or parole makes sense. It may also make sense to put the person in Assisted Outpatient Treatment: a court order to accept mandated and monitored treatment as a condition of living in the community makes sense. See AOT Research. 

The study, "Association of Violence With Emergence of Persecutory Delusions in Untreated Schizophrenia" was by Robert Keers, Ph.D.. Simone Ullrich, Ph.D.; Bianca L. DeStavola, Ph.D. and Jeremy W. Coid, M.D.. It was published in the March 2014 edition of the American Journal of Psychiatry

Abstract at http://www.ncbi.nlm.nih.gov/pubmed/24220644