SEATTLE – Certain symptoms that are present up to month in advance herald psychosis-motivated assaults by psychiatric inpatients, according to a study reported at the annual meeting of the American Academy of Psychiatry and the Law.
Research on assaults by inpatients has focused on static factors and has not differentiated among assaults based on their motivation, lead author Dr. Cameron D. Quanbeck, a psychiatrist at the University of California, Davis, said in an interview.
In the retrospective study, he and his colleagues sought to identify dynamic factors–transient symptoms, behaviors, and situations–that predicted assaults specifically motivated by psychosis.
The investigators assessed the presence of symptom clusters among 26 long-term psychiatric inpatients at the Napa (Calif.) State Hospital (the state's largest forensic hospital) who had schizophrenia or major psychotic disorder, and had assaulted another patient or a staff member.
Nurses' notes were reviewed for the 6-month preassault period and a 6-month historical control period during which the patient had been clinically stable.
The symptom clusters assessed were psychomotor agitation; hostility/angry affect; staff intervention (e.g., seclusion, restraint); paranoid delusions; verbal aggression/attacks on objects; disinhibited, impulsive behaviors; internal preoccupation; anxiety; and depressed, isolative behavior.
Results showed that all nine symptom clusters were significantly more common in the preassault period than in the control period (odds ratios, 2.9–6.9), Dr. Quanbeck reported.
Within the preassault period, six of the clusters were more common in the month before the assault, compared with the preceding 5 months.
Specifically, patients were two to three times more likely to have psychomotor agitation (odds ratio, 1.8); hostility/angry affect (1.7); paranoid delusions (2.3); verbal aggression/attacks on objects (2.7); disinhibited, impulsive behavior (2.6); and the need for staff intervention (3.2) during this month.
Some of these symptoms became even more common and a new symptom (internal preoccupation) appeared as the assault grew yet closer, Dr. Quanbeck noted.
Patients were two to five times more likely to have psychomotor agitation (odds ratio, 3.2), hostility/angry affect (3.2), and internal preoccupation (3.2), and to need staff intervention (5.6) during the last week before the assault, compared with the preceding 3 weeks.
An additional study finding was that none of the patients were taking clozapine (Clozaril) in the preassault period, compared with 40% in the control period. “This suggests that Clozaril is a very effective medication for controlling aggression and the symptoms of psychosis,” Dr. Quanbeck said. The drug has some serious adverse effects, he acknowledged, but they may be an acceptable tradeoff for preventing violence.
The study's findings add to previous research on predicting violence among inpatients, most of which has focused on the day before an assault occurs, Dr. Quanbeck said. “This gives you a longer time frame in which to clinically intervene,” he explained.
In light of the complexity of human behavior, patterns of symptoms are likely more useful than individual ones in predicting assaults, he commented.
“Monitor these patients. Look for this pattern of symptoms that shows up (early),” he recommended. And if patients do become more symptomatic, reevaluate their medications and consider possible interventions (a medication revision, psychotherapy, and stepped-up observation).
“If you can intervene in the preassault period, maybe the assault will not happen,” he concluded.
Dr. Quanbeck reported that he had no conflicts of interest in association with the study.