Posttraumatic stress disorder (PTSD) is a psychological disorder that can develop following exposure to a potentially traumatic event (PTE), that is, one that involves exposure to actual or threatened death, serious injury or sexual violence. Re-experiencing the trauma in the form of intrusive memories, being distressed by reminders, or disturbing dreams at night, is at the core of PTSD. These re-experiencing symptoms sit alongside and interact with the three other symptom groups: avoidance of reminders; negative mood and beliefs about self, others and the world; and ongoing increased physiological arousal.
PTSD can have a significant adverse impact on psychosocial functioning, and as such, is associated with a high level of disability and healthcare costs. When PTSD persists beyond three months it is often comorbid with depression, anxiety and/or substance use disorders.
The prevalence of PTSD needs to be understood in the context of the prevalence of exposure to PTEs. Across their lifetime, most people (50-70%) will be exposed to a PTE and of this group, 15 to 25 per cent will develop PTSD. The 12-month prevalence of PTSD in Australia is 4.4 per cent or approximately 1 million people.
General principles of psychological assessment
Most people experience distress after a PTE and recover without professional help. Only when the person’s distress is persistent or severe enough to cause significant impairment is a comprehensive assessment required.
The assessment should cover trauma history as well as the ‘index’ traumatic event, posttraumatic symptoms, physical health including trauma-related injuries, prior mental health problems, and current social and occupational functioning. Assessment of the person’s strengths and support network is also important since good social support is strongly associated with recovery.
In cases where PTSD is linked to compensation, there may be need for additional objective assessment that will stand up to rigorous scrutiny. This may include a structured clinical interview such as the Clinician Administered PTSD Scale (CAPS; Weathers et al., 2013), or the PTSD Symptom Scale Interview (PSS-I; Foa et al., 1993), a self-report measure such as the PTSD Checklist (PCL; Weathers et al., 2013) and the reports of significant others in the person’s life.
Evidence-based psychological treatment guidance
The cornerstone of psychological treatment involves supporting individuals to confront their memories of the traumatic experience and address associated thoughts and beliefs. To this end, the Australian Treatment Guidelines for the Treatment of Acute Stress Disorder and Posttraumatic Stress Disorder (ACPMH, 2013) recommend trauma-focused cognitive behavioural therapy (TF-CBT) or eye movement desensitisation and reprocessing (EMDR) as the first-line treatment for PTSD. This recommendation is based on a large number of studies, and, although the volume of evidence supporting TF-CBT is larger than that supporting EMDR, six studies that directly compared TF-CBT with EMDR found no difference in the outcomes. For this reason, both are recommended as first-line treatment for PTSD.
- Trauma-focused CBT can include imaginal and in vivo exposure as well as cognitive therapies such as cognitive processing therapy (CPT). Imaginal exposure involves confronting the memory of traumatic experiences through repeated re-telling in a safe environment, while in vivo exposure involves confronting the feared trauma-related situations. The therapeutic mechanisms underpinning exposure therapy are habituation and information processing. Cognitive therapy helps the individual to modify any distorted thoughts and beliefs about the traumatic experience, while CPT, developed specifically for PTSD treatment, includes an exposure element in writing an account of the traumatic experience.
- Eye movement desensitisation and reprocessing is based on the assumption that overwhelming emotions during a trauma interfere with information processing, leading to storage of the experience as ‘unprocessed’ and disconnected from existing memory. In EMDR, individuals focus on trauma-related imagery, thoughts and sensations while simultaneously moving their eyes back and forth following the movement of the therapist’s fingers. It is proposed that this dual attention facilitates the processing of traumatic memory, although the precise mechanism is not known. Over time, traditional CBT interventions such as in vivo exposure have been added to the EMDR protocol.
Emerging treatment directions for the future
Emerging treatment research is examining the potential to enhance the effectiveness of trauma-focused treatments through augmentation with pharmacological agents that promote fear extinction. In addition, treatment research is exploring the potential effectiveness of non-trauma-focused interventions such as mindfulness and acceptance and commitment therapy. These may assist in the treatment of PTSD by reducing physiological arousal and non-judgmental acceptance of distressing emotions and cognitions, but the effectiveness of these interventions is yet to be empirically established.
Key reading and information sources
- Australian Guidelines for the Treatment of Acute Stress Disorder and Posttraumatic Stress Disorder (2013)
- A guide to guidelines for the treatment of PTSD and related conditions (Forbes et al., 2010)