Potentially traumatic events

Potentially traumatic events (PTEs) such as the experiences of the Dowler family are unfortunately prevalent in everyday life. They are defined in the DSM-5 as events that include directly experiencing or witnessing threatened death, serious injury or sexual violence or learning that such an event has occurred to a loved one (American Psychiatric Association 2013). Several population studies have shown that a significant proportion of people have experienced at least one PTE in their lifetime. For example, Costello et al (Reference Costello, Erkanli and Fairbank2002), studying 1420 children and adolescents and their parents or guardians in the USA, estimated that one-quarter of this population had experienced at least one high-magnitude (extreme stressor) event by age 16 and one-third had experienced a low-magnitude (other potentially stressful) event in the preceding 3 months. Hepp et al (Reference Hepp, Gamma and Milos2006), in a study involving 4547 adults in Switzerland, found the weighted lifetime prevalence of PTEs to be 28%. The most commonly occurring PTEs include the unexpected death of a loved one, motor vehicle accidents and being assaulted (Breslau Reference Breslau, Kessler and Chilcoat1998).

Given the high prevalence of PTEs, it is important to study how these experiences can affect mental and physical health. Although not all adverse life events result in PTSD, there has been a wealth of evidence connecting the two (Santiago Reference Santiago, Ursano and Gray2013; Kessler Reference Kessler, Aguilar-Gaxiola and Alonso2017). Where PTSD does occur, the disorder is defined in DSM-5 as consisting of exposure to actual or threatened death, serious injury or sexual violence; presence of one or more intrusion symptoms associated with the traumatic event; persistent avoidance of stimuli associated with the traumatic event; presence of negative cognitions and associated mood symptoms; and changes in arousal and reactivity associated with the traumatic event. These changes should have been present for more than 1 month and must be associated with impairment in functioning (American Psychiatric Association 2013).

Prevalence of PTSD

Helzer et al (Reference Helzer, Robins and McEvoy1987) estimated the prevalence of PTSD in the general American population to be 1%, rising to 3.5% in civilians exposed to physical assault and unwounded Vietnam veterans and reaching 20% in wounded Vietnam veterans. A later study (Kessler Reference Kessler, Sonnega and Bromet1995) put the prevalence at 7.8% for the general American population, whereas a more recent systematic review (Santiago Reference Santiago, Ursano and Gray2013) found an estimated prevalence of 28.8% (range 3.1–87.5%) at 1 month, reducing to 17.0% (range 0.6–43.8%) at 12 months following exposure to trauma. It is thought that the effects of trauma could be differential over the life course. Ogle et al (Reference Ogle, Rubin and Berntsen2013) found that events that occurred with greater frequency early in life were associated with more severe PTSD symptoms compared with events that occurred with greater frequency during later decades of life. The experience of PTEs has been connected with the development of sleep disturbances (Milanak Reference Milanak, Zuromski and Cero2019), depression (Tracy Reference Tracy, Morgenstern and Zivin2014), substance use (Khoury Reference Khoury, Tang and Bradley2010), and other trauma- and/or stressor-related disorders, such as acute stress disorder, adjustment disorder and bereavement-related disorders (O'Donnell Reference O'Donnell, Alkemade and Creamer2016).

In addition to their effects on mental health, it has been well established that PTEs have negative effects on physical health. A cross-sectional study of 38 051 participants across 14 countries by Scott et al (Reference Scott, Koenen and Aguilar-Gaxiola2013) found a dose–response association between the number of adverse life events and the odds of developing a physical health condition (OR = 1.5, 95% CI 1.4–1.5 for one adverse life event; OR = 2.1, 95% CI 2.0–2.3 for five or more), independent of PTSD and other mental illnesses. Implicated physical health conditions were arthritis, back and neck pain, heart disease, high blood pressure, diabetes and peptic ulcer disease. Keyes et al (Reference Keyes, McLaughlin and Demmer2013), studying more than 2500 adult African Americans in Detroit, Michigan, found that respondents with the highest levels of PTE exposure (eight or more events) had an average age at diagnosis of an adverse physical health condition that was 15 years earlier than respondents with no exposure. Furthermore, there was a positive correlation between the number of PTEs and the risk of developing arthritis.

A meta-analysis by Pacella et al (Reference Pacella, Hruska and Delahanty2013) examined the association between PTSD and physical health outcomes. The results revealed a significantly greater number of general health symptoms and general medical conditions, as well as a poorer overall health-related quality of life in those with PTSD. PTSD was found to be associated with an increased frequency and severity of pain, cardiorespiratory symptoms and gastrointestinal complaints. There is also substantial evidence that PTSD is associated with an increased risk of cardiovascular disease (Buckley Reference Buckley, Tofler and Prigerson2013). This association has been observed across military and civilian populations and exists independent of other risk factors. It has been postulated that PTSD may lead to adverse physiological changes, which then lead to transient ischaemia, plaque disruption and thrombosis, resulting in the development of acute coronary syndrome. Hence, the recognition and treatment of trauma, PTSD and related sequelae should be considered important public health goals (Magruder Reference Magruder, McLaughlin and Elmore Borbon2017).

Psychotherapeutic interventions

A variety of psychotherapeutic options are available for the treatment of traumatic experiences and PTSD, including prolonged exposure therapy, cognitive–behavioural therapy (CBT) and cognitive processing therapy. However, EMDR has recently been gaining favour in the treatment of these conditions. It is distinguished by its potential to reduce the symptoms associated with traumatic memories in fewer sessions, as well as its ability to resolve trauma without the patient necessarily needing to discuss the details of the event in great depth. This article therefore aims to cover what EMDR therapy is, what the procedure entails, the evidence supporting its efficacy in treating PTSD, and indications and contraindications for its use.

Theoretical underpinnings

The theory behind how EMDR works is based on the adaptive information processing model. When new experiences are processed by the brain, they are assimilated into already existing memory networks, which are the basis of our perceptions, attitudes and behaviours. According to this model, trauma causes a disruption in this information processing, resulting in unprocessed experiences being stored maladaptively in their own neural network, unable to link up with other networks that hold adaptive information. These unprocessed memories still contain the thoughts, emotions and physical sensations that occurred at the time of the event and so when they are triggered, these distressing elements are re-experienced, causing the symptoms of PTSD (Solomon Reference Solomon and Shapiro2008). Therefore, the goal of EMDR is to reprocess traumatic memories by changing the way they are stored in the brain to relieve the distressing symptoms associated with them. It is not known exactly how EMDR achieves this effect; however, it is thought that bilateral stimulation while recalling a traumatic memory helps to accelerate the innate processing system to facilitate the linkage of this unprocessed memory to adaptive memory networks.

A significant amount of research has been conducted to both further elucidate its mechanism of action and further characterise its efficacy in treating trauma, in addition to a variety of mental illnesses. On the basis of this research, EMDR has been recognised by many organisations, including the American Psychiatric Association, the American Psychological Association, the International Society for Traumatic Stress Studies, and the World Health Organization, as an effective treatment for trauma and PTSD.

Information and training

The following professional associations are among those offering information on EMDR and approved training:

• • EMDR Association UK (https://emdrassociation.org.uk/)

• • EMDR All-Ireland Association (https://emdrireland.org/)

• • EMDR International Association (EMDRIA) (https://www.emdria.org/).

Grief and loss

The death of a loved one can be a very distressing experience. In line with the adaptive information processing model, it is thought that the associated memories may be improperly stored in the brain, preventing access to adaptive information, such as positive memories of the deceased. Therefore, EMDR may facilitate appropriate movement through the mourning processes, reducing dysfunctional symptoms in those who are struggling with grief. This idea has been supported by the results from three RCTs.

An RCT by Meysner et al (Reference Meysner, Cotter and Lee2016) randomly assigned 19 participants struggling with grief to 7 weeks of either EMDR or CBT. Participants in both groups improved on measures of grief, trauma symptoms and distress but not on a measure of quality of life. There were no significant differences in outcomes between the two groups, suggesting that both treatments were efficacious. Two weeks after completing this study, a semi-structured interview was conducted with participants to explore their experiences with the two approaches (Cotter Reference Cotter, Meysner and Lee2017). Participants in both groups reported developments in insight, a positive shift in emotions, increased activity, improved self-confidence and a healthier mental relationship with the deceased. Additionally, participants who received EMDR reported that distressing memories were fewer and felt more distant.

Additionally, two RCTs have assessed a combined treatment approach for grief. van Denderen et al (Reference van Denderen, de Keijser and Stewart2018) compared symptoms of complicated grief and PTSD in 85 individuals bereaved by homicide who were assigned to either an eight-session treatment encompassing CBT and EMDR or a waiting list. Compared with the waiting list, there was a significant reduction in complicated grief and PTSD symptoms following treatment with EMDR plus CBT. Lenferink et al (Reference Lenferink, de Keijser and Smid2020) randomly assigned 39 participants who had experienced loss related to a major plane crash to either cognitive therapy plus EMDR or a waiting list control. Changes in self-rated persistent complex bereavement disorder (PCBD), depression and PTSD levels were explored. The treatment group showed a significantly stronger decline in depression compared with waiting-list controls; however, there were no significant between-group differences found in PCBD and PTSD levels. Symptom reductions were correlated with reductions in maladaptive cognitive–behavioural variables.

The results of these studies suggest that, given the common overlap between trauma and grief in the experience of loss, EMDR may be effective in reducing the associated symptoms of distress; however, further research is needed to assess whether EMDR is effective on its own or if it is best utilised in combination with CBT.

Sexual assault

Three studies have investigated the use of EMDR in treating anxiety, depression and trauma symptoms in women who have experienced sexual assault. Rothbaum (Reference Rothbaum1997) randomised 21 participants who had been sexually assaulted to either three sessions of EMDR or a waiting list. Those treated with EMDR improved more on depression and PTSD scores compared with the control group. However, the author notes that the study suffered from a small sample size and a lack of comparable treatment as a control.

Scheck et al (Reference Scheck, Schaeffer and Gillette1998) conducted an RCT in which 60 women aged 16–25 who had experienced traumas such as rape or childhood molestation were randomly assigned to receive two sessions of either EMDR or active listening. Although both groups improved on measures of anxiety, depression and PTSD symptoms, greater improvements were found in the EMDR group, which were enough to place these participants in the normal range post-treatment. These results are limited by the few sessions of treatment offered, the self-report nature of the outcome measures and the lack of objective validation that the fidelity of the study protocol was adhered to.

Mankuta et al (Reference Mankuta, Aziz-Suleyman and Yochai2012) describe their experience of providing mental health services to women who had suffered severe sexual assault, which in some cases involved genital mutilation. In their short-term project in the Democratic Republic of Congo, 23 out of 26 women diagnosed with severe PTSD were successfully treated with EMDR. There was no presentation of exactly how data changed during or after EMDR. In a similar field study in the same country, EMDR was successfully used in individual and group therapy settings (Allon Reference Allon2015).

Although these studies demonstrate the potential value of EMDR in sexual assault services, at least one study has shown that EMDR is possibly being underutilised. In a cross-sectional study of the extent to which rape crisis centres in Texas, USA, utilise EMDR therapy, Edmond et al (Reference Edmond, Lawrence and Schrag2016) found a low rate of use (at 8%). Practitioner perceptions were hindered by uncertainty regarding EMDR's effectiveness, which the authors felt reflected a lack of familiarity with EMDR, although there was strong interest in receiving training. Although this result is not generalisable, its implications are that sexual assault services may not be delivering the full array of evidence-based treatments to this vulnerable population.

Violence and abuse

Several studies have investigated EMDR's ability to reduce symptoms associated with trauma secondary to violence and abuse. Wright & Russell (Reference Wright and Russell2013) described the use of EMDR in the management of violent impulses secondary to combat exposure in the case of an active-duty marine. Following four sessions of EMDR, the marine showed improvements in obsessive violent impulses, traumatic grief and depression. The authors were careful to caution that their case demonstrates that ‘the ability to potentially intervene and prevent suicide and IPV [interpersonal violence], in whatever the numbers, can make a profound difference in the life course of those who would be victims, perpetrators, and their respective families’ members for generations to come’.

Brennstuhl et al (Reference Brennstuhl, Tarquinio and Strub2013) compared the efficacy of an EMDR emergency protocol (URG-EMDR) in treating 19 recent (defined as within 48 h) victims of physical violence in the workplace with that of eclectic therapy received by 15 similar victims. The workplaces were large-scale retail and civil service offices. Participants had to exhibit symptoms of acute stress disorder, as listed in DSM-IV, have clinical symptoms that could be attributed to the workplace incident and for which a consultation occurred within 48 h, and be first-time victims of violence or a PTE. Those taking any kind of medication were excluded. URG-EMDR resulted in a greater decrease in perceived stress and PTSD scores than eclectic therapy, to the extent that 3 months later, none of the EMDR-treated individuals exhibited symptoms of post-traumatic stress. The value of this study is that it showed that the early use of EMDR may prevent the onset of PTSD. However, the study was limited by a small sample size and a lack of longer-term follow-up. There was also no randomisation, although participants appeared broadly similar in characteristics.

Similarly, Tarquinio et al (Reference Tarquinio, Rotonda and Houllé2016) conducted an RCT investigating the efficacy of EMDR as an early intervention for workplace-based violence. In their study, 60 victims of workplace-based violence received one of three interventions: the EMDR Recent [Traumatic] Events Protocol (EMDR-RE, n = 19), Critical Incident Stress Debriefing (CISD, n = 23) or delayed EMDR-RE (n = 18). The first two interventions occurred 48 h after the event, while delayed EMDR-RE occurred 96 h thereafter. Three months on, post-traumatic stress scores were significantly lower in the EMDR-RE and delayed EMDR-RE groups compared with the CISD group. After both 48 h and 3 months, none of the EMDR-RE-treated victims showed PTSD symptoms. This study was limited by a lack of longer-term follow-up, small numbers and possible participation bias.

Evidence in the area of violence and abuse has focused more on victims of violence than on perpetrators. Interventions involving EMDR in this area are often complex and multifaceted, making it difficult to attribute improvements solely to EMDR treatment. Studies are often limited in sample size and often produce lower level evidence. Nevertheless, current evidence suggests that EMDR may be useful in resolving acute stress disorder associated with experiences of violence.