Incidence, Severity and Characteristics of Patients’ Aggression in Acute Psychiatric Wards: Data from a Slovenian National Survey

In patients with mental disorders, aggressive behaviour is three to five times more common than in the general population (1, 2). A recent systematic review of studies found that the prevalence of aggressive behaviour in psychiatric wards varied from 8-76% (3). Aggressive behaviour most commonly occurs in a hospital setting, often immediately upon admission to a psychiatric emergency room or an acute psychiatric ward. Data from a meta-analysis of 35 studies showed that the prevalence of aggressive behaviour in acute psychiatric units in developed countries ranged from 3 to 44% (4). Recurrent episodes of aggression are common, and studies show that only a minority of patients are responsible for more than half of all incidents (3).

Most of the aggressive behaviour is directed at medical staff (4, 5). In psychiatric hospitals, 89% of the staff experience verbal aggression and more than half experience physical aggression (6). Verbal aggression is the most reported form of aggression, described in more than 80% of incidents, however, about half of the incidents involve physical aggression (5, 7). In a recent survey in Swiss psychiatric hospitals, almost 30% of nurses reported they had experienced a severe aggressive attack during their professional lives (8).

Risk factors for aggressive behaviour can be categorized into intrinsic factors related to the patient, and extrinsic factors related to the ward environment, staff and patient-staff relationships (2, 9). Intrinsic risk factors include patient diagnosis, history of psychiatric treatment and aggressive behaviour, involuntary admission, length of hospital stay, psychopathological phenomena, biological factors, and sociodemographic factors (2, 3). A recently published systematic literature review found that high bed capacity occupancy, ward crowding, lack of daily structure or privacy, smoking and a restrictive environment were the most important ward factors associated with aggressive behaviour (3). Limitation of the patient’s requests or wishes, most often the desire to leave the hospital, is one of the most common triggers of aggression (10). On the other hand, interactions between patients and staff are often the main factor in the escalation and maintenance of aggression (3).

Aggressive behaviour affects patient and staff safety, has a negative influence on their mental and physical health, and can lead to a bad reputation for the hospital (11). Both patients and staff feel victimized, but for different reasons. Patients report being victims of staff control within the restrictive ward environment, and staff feel victimized by patient aggression and an inappropriate work environment and organization. Such feelings have a significant negative impact on the therapeutic relationship (12, 13). The consequences for patients are longer hospital stays, more frequent use of coercive measures, and higher doses of psychotropic drugs, all of which are associated with more complications (13, 14). Staff exposed to aggressive behaviour often experience feelings of anger, anxiety, guilt, shame, helplessness and disappointment. Decreased motivation and job satisfaction are common consequences (6, 7). Staff exposure to aggression is associated with mental disorders such as depression, anxiety symptoms, sleep problems, post-traumatic stress disorder and burnout syndrome, which occur primarily with chronic exposure and by inexperienced staff (11, 15, 16). A recent study by Italian authors showed that exposure to verbal or physical aggression increased the incidence of burnout among mental health professionals (17). Absenteeism is more common among staff exposed to physical aggression and sexual harassment, and leaving or changing jobs are also common consequences (15, 18). The economic consequences associated with aggression and its management should not be overlooked. A Spanish study estimated the cost of specific interventions related to the management of aggression in an acute psychiatric ward to be 6.87% of the total annual hospitalization costs (19).

The study was the initial part of a large project of the Slovenian Psychiatric Association, which was carried out from 2018 to 2020, and was aimed at reducing aggressive behaviour in acute psychiatric wards. The study was approved by the Slovenian National Medical Ethics Committee (0120-74/2018/4).

The first Slovenian data on aggressive behaviour for all acute psychiatric wards are presented. Although the frequency of aggressive behaviour in acute psychiatric settings in developed countries varies greatly (3, 4), on average the data are comparable to our national data. The proportion of aggressive patients in our sample was 13.4%, which is comparable to the results of the Swiss study by Abderhalden et al. (26) but slightly lower than a meta-analysis of 35 studies conducted in acute psychiatric wards in developed countries (17%) showed (4). The incidence of aggressive events per bed per year was 9.5, which is comparable to the average rate (9.3) observed in European acute psychiatric wards (27). Compared to the study from Abderhalden et al. (26), the incidence rate per 100 treatment days was 40 to 60% higher in the Slovenian population. The lower incidence in the Swiss survey may reflect the fact that, in addition to closed wards, there were also part-time closed wards included and, to a lesser extent, wards without seclusion rooms, where the patients with the most severe pathology, who are most often aggressive, are less likely to be treated. In Slovenia, acute psychiatric wards are closed wards, and patients are treated for a variety of psychopathology, including organic mental disorders and delirium, which are known to be associated with aggressive behaviour (28). Aggression risk assessment and staff de-escalation training are still sporadic, and a systematic prevention strategy is lacking in all hospitals.

A large proportion of aggressive incidents were severe, with the mean severity of aggression slightly higher than in other similar studies (5, 26). The high proportion of severe incidents in our study may be due to the underestimation of less severe incidents without clear perceived consequences. Staff working with patients with severe mental disorders often perceive mild, especially verbal forms of aggression, as normal behaviour of patients with an acute mental disorder rather than as a distortion (11). Increased tolerance of aggressive behaviour and the perception of aggression as “part of the job” are particularly pronounced among staff working with patients with mental disorders, the elderly population and in emergency rooms (13, 29). Psychiatric nurses reported lower levels of stress after being verbally attacked than other nurses (30). Therefore, it is possible that the high proportion of severe incidents in our study is due to the underestimation of less severe incidents. On the other hand, the high rate of severe incidents may also be related to the subjective perception of a greater proportion of aggressive behaviour as threatening. According to some researchers, the item “being threatened” in the SOAS-R scale is unclear, as it is not further defined to whom the threat refers (5). The assessment of being threatening is subjective, but at the same time, this item contributes a high proportion (6 points) to the total score on the SOAS-R. Thus, most incidents that cause a feeling of danger are assessed as severe. Feeling threatened is one of the most frequently described consequences of aggressive behaviour (10), which is confirmed by our findings.

Abderhalden et al. found that up to 46% of incidents of verbal aggression were classified as severe, and 43% were followed by the use of coercive measures (26). Our study found an even higher rate of severe verbal incidents (59.8%). Approximately half of the incidents assessed as severe were followed by the introduction of physical restraints, which indicates the seriousness of these incidents, as the decision to introduce restraints is usually made within the staff team with the psychiatrist’s approval and is not based on a risk assessment by an individual staff member. Seclusion is almost never used in acute psychiatric wards in Slovenia, mainly due to inadequate room capacities and the inability to adequately monitor such patients.

In almost half of the incidents in our study, staff did not identify a trigger for aggressive behaviour, which is consistent with findings from other researchers (5, 26). Some authors report that the reason for the high proportion of unrecognized causes may be due to the limited number of possible trigger items listed in SOAS-R (5). However, the staff who complete the scale could list other causes that they recognize. In fact, the staff in our survey entered specific causes of aggression under the item “other provocations” on the SOAS-R in 14% of incidents. The attitudes of staff and patients related to the causes of aggressive behaviour differ. From patients’ perspectives, aggressive behaviour is associated with staff attitude and interpersonal skills, inadequate communication, the use of coercive intervention or a controlling approach, ward structure and treatment procedures (31). On the other hand, staff often do not recognize their involvement in the process of escalating aggression and attribute aggressive behaviour to internal patient factors (9). However, the systematic review of seventy-one studies revealed that staff-patient interaction was the most frequent antecedent of aggression, precipitating 39% of all incidents (32). Among the identified triggers, in our research, rejection of the patient’s requests was the most frequently described, as some other authors also noted (10). This fact could be important in the planning of interventions aimed at reducing aggressive behaviour, as most de-escalation programmes involve interventions focused on this issue.

In our study, the highest proportion of aggressive incidents were recorded during the day, but these were rated as less severe compared to incidents in the afternoon and night shifts. More frequent aggressive behaviour during the day may be related to more staff on the ward, more activities, court hearings and visits. During the day, patients are more often faced with various rejections of their requests, such as being discharged, reducing therapy, or transferring to an open ward, which are the most common triggering factors of aggressive behaviour identified in our and other studies (24). Among incidents on the night shift, a sense of threat was more commonly reported, which may also be due to subjective experience associated with fewer staff on the ward at night. The staff-to-bed ratio during the study ranged from 0.1 to 0.3, which is low compared with some other European countries (33). Weekend and night shifts have the lowest ratio.

Consistent with previous studies, approximately 20% of aggressive patients accounted for nearly half of all incidents (3). Among patients with recurrent incidents, the proportion of those with a main diagnosis of F1 was lower compared to patients with a single incident. This can be explained by the temporary and transitory effect of intoxication on aggressive behaviour. Patients with recurrent incidents had on average longer hospitalizations, as shown by the results of other studies (34). However, the cause-and-effect relationship is not entirely clear. Patients with longer hospitalizations often have severe mental disorders associated with an increased risk of aggression. On the other hand, patients with longer hospitalizations have a longer period in which incidents may occur.

In Slovenia, preventive strategies and mechanisms for managing aggression should be introduced in all psychiatric hospitals. Assessing the frequency, characteristics and long-term monitoring of aggressive behaviour may be a good start to this challenging task.