Benjamin Rose , Charles Broderick , Darci Delgado , Rebecca Kornbluh , and Stephen M. Stahl
Inpatient aggression within psychiatric facilities continues to demand attention. Aggressive acts often cause physical or psychological injury that impact the lives of the patients or staff victims of these incidents. However, it should be noted that the vast majority of psychiatric patients are not aggressive while hospitalized. Studies on inpatient aggression1–3 showed approximately 25%–35% of inpatients committed acts of aggression. For those inpatients who are aggressive, there is a substantial literature that describes a small subset of “chronically aggressive” patients, who are responsible for the majority of inpatient aggression.4–11
Numerous research studies have described clinical characteristics of inpatient psychiatric patients who meet some definition of a chronic aggressor.4,8,12 While there has not been universal agreement in past studies, several clinical characteristics have been shown to be significant in discriminating between the chronically aggressive and nonaggressive populations, including: cognitive deficits,4,13,14 suicidal behavior,12,14 borderline or antisocial personality disorder,4,15,16 history of substance use,4 diagnosis of schizophrenia or psychosis,10,13 hospitalization as a juvenile,12 and diagnosis of a mood disorder.4,12
Given the amount and variety of these clinical characteristics, it is difficult to develop a cohesive theory based on the heterogeneity of the results, and given a finite amount of resources, develop specialty programs that address all of these problems. This informational morass has provided challenges to researchers and clinicians trying to piece together many different clinical features of this population.
Research on the topic of chronic aggression has been clouded by a variety of labels as well as definitions. Studies, that have investigated patients with multiple aggressive acts, have used different terms to describe these patients, such as “chronically aggressive,” “repeatedly aggressive,” and “chronically violent.” While every study reviewed included aggression toward others, there was a lot of variability on the inclusion of aggression toward self, aggression toward property, and verbal aggression. In addition, the primary method of determining if a patient was chronically aggressive has been to set a minimum number of aggressive incidents and a time frame for those incidents to be committed. The number of incidents has ranged from a minimum of 2–20 and the time frame has varied from 5 months to 10 years. This variability creates a problem in clearly defining the group of patients to be studied. A patient committing 20 acts of aggression within 5 months will likely look clinically different from a patient committing 20 aggressive acts within 10 years.
This issue of variability in definitions was highlighted in a study by Krakowsi and Czobor13 who subdivided a sample of aggressive patients into a “transiently violent” group and a “persistently violent” group. Their findings showed that the transiently violent patients became less psychotic and less violent over a four-week period, whereas the persistently violent did not show any substantial changes in illness or violence. Further investigation showed the persistently violent patients showed more neurological impairment than the transiently violent patients. The positive response to treatment in the transiently violent group highlights the impact that psycho-pharmacological treatment can have for psychosis, but also highlights the relative lack of benefit for persistently violent patients with neurological impairment. Despite the differences in the clinical picture and response to treatment, several studies have lumped these two groups of patients together when conducting research on chronic aggression.
Despite the short four-week duration, Krakowski and Czobor’s13 model, dividing patients into transiently violent and persistently violent groups, provides a useful blueprint for further study. In their model, the transiently aggressive patients were individuals who were aggressive for a period of time but as a result of treatment, time, or other factor, greatly reduced or eliminated their aggressive behavior. The persistently violent patients were those that remained aggressive despite psychopharmacology, therapies, extra resources, reviews by expert clinicians, and other varied interventions. One criticism of their model is the short amount of time that passed before a patient was considered persistently violent. Several psychopharmacological and psychiatric treatments can take months to be effective and so it is unclear if the treatments had worked in the study. In addition, the short duration does not allow researchers to determine if the patient was consistently aggressive.
The aim of the study was to further refine the definition “chronic aggressor” and study patients who had been consistently aggressive over multiple years, labeling this group as, “long-term chronic aggressors.” To better understand this group, we then contrasted them with a matched control group to see if we could classify patients into a long-term chronic aggressor group or a nonaggressor group based on the clinical factors that were most related to chronically aggressive patients. More specifically, we aimed to test whether common characteristics of the chronically aggressive patients were present in the long-term chronic aggressive patients.
In an effort to study a long-term chronic aggressor, a more stringent inclusion criterion was used. In this study, we required that a patient have at least 15 incidents of physical aggression, we believed that having a stricter definition would provide a better contrast to the control group. This number is on the high end of what previous studies have required to be considered a chronic aggressor. In addition to the count of aggressive incidents, a consistency factor was implemented, which required a patient to be consistently aggressive five times for three years, for a total of at least 15 aggressive incidents. Only aggressive acts that were physical assaults toward another patient or staff member were counted. Acts such as verbal aggression, aggression toward self, or aggression toward an object or property were not counted in this study.