Delusions, anger, and serious violence: new findings from the MacArthur Violence Risk Assessment Study.

Résumé

INTRODUCTION: Recent research on the association between delusions and violence has suggested complex and differing pathways. Furthermore, it has been emphasized that temporal proximity is fundamental when investigating these relationships. We reanalyzed data from the MacArthur Violence Risk Assessment Study utilizing a different methodological approach to investigate associations between specific delusions and violence.METHODS: Longitudinal study of 1136 male and female civil psychiatric inpatients after discharge. Delusions, affect due to delusions, and violence were measured at baseline and in 5 follow-up assessments. Serious violence was established using the MacArthur Community Violence Interview. Logistic mixed-effect models for repeated measures were performed.RESULTS: A "prospective" model confirmed previous findings that delusions do not predict later violence. However, reanalysis, considering temporal proximity, indicated a relationship between specific delusions and outcome including: being spied upon (adjusted OR [AOR] = 1.62, 95% CI = 1.06-2.47, P = .027), being followed (AOR = 1.90, 95% CI = 1.29-2.80, P = .001), being plotted against (AOR = 1.70, 95% CI = 1.14-2.52, P = .009), being under control of person/force (AOR = 1.92, 95% CI = 1.24-2.97, P = .003), thought insertion (AOR = 1.63, 95% CI = 1.00-2.66, P = .048), and having special gifts/powers (AOR = 1.95, 95% CI = 1.31-2.92, P = .001). All these delusions were associated with angry affect (P < .05). Inclusion of anger in the model significantly attenuated the main effects (except grandiose delusions), indicating an indirect pathway.CONCLUSIONS: Temporal proximity is crucial when investigating relationships between delusions and violence. Anger due to delusions is the key factor in this pathway. Our findings have important implications for identification of psychotic patients at risk for violent behavior and, most importantly, management of their risk.