(September 3, 2019) Poor medication adherence in people with schizophrenia is a significant factor in predicting future violent behavior, according to new research published in The American Journal of Psychiatry.
Dr. Alec Buchanan and colleagues examined factors that correlate with violence among individuals being treated for schizophrenia. The study’s objectives were to better understand risk assessment and care because “violent behavior is infrequent among individuals with schizophrenia but is clinically important.”
The researchers conducted a new analysis of the National Institute of Mental Health Clinical Antipsychotic Trials of Intervention Effectiveness, a randomized control trial of antipsychotic medications conducted in 57 different sites in the United States in the early 2000s. The study included 1,435 individuals being treated for schizophrenia and followed those enrolled for 18 months, measuring a variety of clinical indicators and behaviors, including psychosis symptoms, injurious and non-injurious violence, as well as risk factors for violent behavior such as childhood abuse or substance use.
All participants met diagnostic criteria for schizophrenia. The study group had, on average, severe and long-standing illness, with the mean time since first treatment more than 16 years prior and only 13% of the study group participating in any vocational activities. More than 20% of those enrolled reported experiencing violent sexual abuse before the age of 15.
The authors utilized a methodological approach not previously conducted on this data to study the correlates of injurious versus non-injurious violence, i.e., factors that may predict violence that hurts someone else or violent behavior that does not injure anyone such as violence towards objects or verbal assaults.
Only 14% of the enrolled individuals with schizophrenia reported displays of violence in the 18-month follow-up period, and the majority of the violence was non-injurious. Therefore, 1,204 of the 1,435 individuals with schizophrenia exhibited no violent behaviors at all.
Recent violent victimization was also a strong predictor for future injurious violent behavior. This means that recently being a victim of violence increases the likelihood of future violent behavior among individuals with schizophrenia. Both of these factors had larger effects in predicting violent behavior than psychosis symptoms alone.
Further analysis of the results indicates a strong effect of baseline injurious violence on future injurious violent behavior, consistent with previous research that prior violent behavior may, in part, serve as a predictor of future violence.
For clinical factors, poor medication adherence in individuals with schizophrenia was a significant predictor of injurious violence. The authors write that these results speak “to the important contribution of maintaining a therapeutic alliance in the management of violence risk.”
The authors emphasize the value of understanding the correlates of violence in individuals with schizophrenia, especially for mental health providers who have a responsibility to reduce the risk of violence in individuals in their care. Treatment strategies to reduce violence should emphasize medication adherence and engagement of individuals in care, especially for those in at-risk populations.
References:
Elizabeth Sinclair
Director of Research
Treatment Advocacy Center