Adult abuse and poor prognosis in Taiwan, 2000–2015: a cohort study

Abuse is the mishandling or use of something, usually for unfair or improper advantage [1]. Abuse can take many methods, such as physical abuse or injury, rape, assault, unfair methods, crime, or other types of assault [2]. Physical and emotional abuse is harmful and can lead to mental illness [3]. It can be associated with verbal and non-verbal abuse and can humiliate, intimidate and isolate a person's mind [4]. Using physical injury, abuse, damage or destruction as a source of violence [4]. Violence can be physical, psychological, social, financial, or sexual assault [3, 4]. Violence can be intermittent, occasional, or chronic [5]. The emotional impact of adult abuse leading to isolation, fear, and mistrust can have lifelong adverse outcomes, including poor psychosomatic and behavioral health and increased risk of adverse outcomes [6]. Dating violence, domestic violence, human trafficking, child abuse and neglect, sexual assault and elder abuse are relationship violence [7]. Abuse can happen at any time and to anyone and has severe, lasting negative emotional, mental, and physical effects on the victim [8]. Violent injury and suicide are closely related major public health issues [9].

World Health Organization (WHO) estimates that it is estimated that hundreds of thousands of people worldwide die by suicide every year [10]. Complex combination of demographic characteristics, social risk factors, mental illness and substance abuse, and multilevel causality lead to suicide [11‐18]. Previous research has found strong associations between adult abuse and suicide, mental health problems, substance abuse, social isolation, trauma, and violence [19]. Murder-suicide cases most likely in context of abuse, intimate partner violence (IPV) survivors twice as likely to make multiple suicide attempts [20].

A better understanding of the physical and mental health effects on adults who experience violence and suicide can help lift public health efforts to the next level. Longitudinal observational studies on the relationship between adult abuse and poor prognosis (schizophrenic disorders, psychotic disorders, suicide, or self-inflicted injuries and mortality) are limited. Therefore, we hypothesized that adults exposed to violence risk poor prognoses (schizophrenic disorders, psychotic disorders, suicide, or self-inflicted injury and mortality). We used NHIRD to track whether adults experiencing violence were at risk of poor prognosis (schizophrenic disorders, psychotic disorders, suicide, or self-inflicted injury and mortality) from 2000 to 2015 through long-term follow-up in Taiwan.

The findings showed that adults who experienced violence had a significantly higher risk of developing schizophrenia, psychosis, suicide or self-harm, and death) than adults who did not experience violence. The risk of poor prognosis (adults overall) was suicide or self-inflicted injury (HR = 6.87), schizophrenic disorders (HR = 5.63), psychotic disorders (HR = 4.10), and risk of mortality (HR = 2.50). The risk of poor prognosis (male adults) was schizophrenia (HR = 5.66), psychotic disorders (HR = 3.85), suicide or self-inflicted injury (HR = 3.59), and risk of mortality (HR = 2.51). The risk of poor prognosis (female adults) was suicide or self-inflicted injury (HR = 21.93), schizophrenic disorders (HR = 5.57), psychotic disorders (HR = 4.60), and risk of mortality (HR = 2.46). Adults following violent injury are at highest risk for suicide or self-inflicted. Male adults suffer from violence were at the highest risk of developing schizophrenia. Further, female adults suffer from violence were at the highest risk of suicide or self-inflicted injuries. Suicidal behavior is strongly associated with experiencing conflict, disaster, violence, abuse or loss, and feelings of isolation [23]. In addition, refugees and immigrants experience high rates of suicide among discriminated populations [24]. Men and women may develop schizophrenia at the same rate, but men tend to develop schizophrenia earlier [25]. On average, males are diagnosed with schizophrenia in their late teens to early 20s, while females are diagnosed with schizophrenia in their late 20s to early 30s [26]. Females are nine times more likely to experience IPV than males [27].  Females are twice to suffer from Post-Traumatic Stress Disorder (PTSD) [28]. IPV can lead to PTSD, which is also a risk factor for suicide [29]. Suicide or self-harm are unhealthy strategies that women may use to cope with abuse [30], which is consistent with our study.

Mental illnesses, particularly PTSD, depression, anxiety, and alcohol use disorders (AUD), are well-known risk factors for suicide and self-harm [31]. PTSD is a known risk factor for self-harm and suicide [31, 32]. 10% of women suffer from PTSD at some point in their lives, compared to 4% of men. PTSD study shows women are twice as likely as men to suffer from PTSD [33]. Young women are more likely than men to experience high-impact trauma [34]. When type II trauma is involved, it disrupts neurobiological development and personality [33, 34].

Estimates published by WHO indicate that approximately one-third (30%) of women worldwide have experienced physical or sexual intimate partner violence or non-partner sexual violence during their lifetime [35]. Violence leads to unhealthy coping strategies that can ultimately destroy self-worth, lead to PTSD and depression, and put women at greater risk of suicide [36]. Our study found that adults exposed to violence were at the most significant risk of suicide or self-inflicted injuries. Women were at the highest risk of suicide and self-inflicted injury due to violence.

Schizophrenia that affects a person’s thinking, behavior, emotional expression, perception of reality, and relationships with others [37]. Although schizophrenia is not as common as other major mental illnesses, it can be the most chronic and disabling [38]. Individuals who experienced emotional abuse in early life were 3.5 times more likely to experience schizophrenia in adulthood [39]. The more severe the abuse, the more severe the schizophrenia-like experiences in adults [40]. Exposure to violence, traumatic brain injury, or substance intoxication can act as a single trigger to increase risk of short-term violence in schizophrenia and controls [41, 42]. Our study found that male adults exposed to violence were at the highest risk of developing schizophrenic disorders.

In today’s society, psychotic disorders and violent abuse are often inextricably linked, creating a harsh stigma for patients and sometimes an uncomfortable environment for psychiatrists [43]. Dealing with violent injuries in victims have become a growing concern in the psychiatric practice. Numerous patients of assault present to emergency departments, and psychiatrists are often called upon to assess and treat such violently injured patients [44]. Victims of violence have a much higher risk of having mental health disorders than the general population [45‐50]. Our study found that adults exposed to violence risk psychotic disorders.

Every year, more than 1.6 million people die from violence worldwide [51]. Victims of violence are associated with excess mortality and risk of suicide [52]. It is essential to systematically screen for violence victimization in clinical settings to identify at-risk individuals [53]. Similarly, in clinical work, patients with victimization experiences should be screened for substance abuse and should be treated comprehensively [54]. Our study found that adults exposed to violence were at risk of mortality.

Several limitations in the study. First, similar to previous studies that used the NHI Mental Illness Research Database [55], we were unable to assess genetic psychosocial or environmental factors, severity, or psychological assessment in individuals with mental disorders because data were not recorded in NHIRD. Second, the study was conducted on adults who had experienced violence and sought medical care. so investigators only examine those who have experienced more severe violence, whose incidence may be underestimated. Third, this study examined medical violence cases, which may minimize the harm caused by violence. In particular, domestic violence cases and violence without obvious trauma or other unexplained psychological abuse events: Victims that did not seek medical treatment.

The risk of poor prognosis (schizophrenic disorders, psychotic disorders, suicide, or self-inflicted injury and mortality) among adults subjected to violence is significantly higher than those who were not been subjected to violence. Adults who have experienced violence are at the highest risk for suicide or self-harm. Males who experience violence are at highest risk for schizophrenia. Females who experience violence are at the highest risk of suicide or self-harm. Therefore, in addition to avoiding violent incidents, medical and social welfare personnel should also be concerned with the mental health and risks of schizophrenia, mental disorders, suicide, self-harm, and death in violent adults.

Future studies should investigate changes in poor prognosis (schizophrenic disorders, psychotic disorders, suicide, or self-inflicted injury and mortality) over the observation period from 2016 to 2022.