Getting better outcomes from posttraumatic stress disorder treatments

By Dr Olivia Metcalf, Dr Mark Hinton and Dr Tracey Varker

 

Several effective treatments for posttraumatic stress disorder (PTSD) exist, yet nearly half of patients continue to have significant symptomatology after receiving them (e.g., Foa et al., 2018). Augmentation is a way of improving outcomes from standard treatments by adding something before, during, or after standard treatment.

 

Augmentation can work in lots of different ways, and might mean faster or greater symptom improvement relative to standard treatment alone, better engagement or retention with standard treatment, or improved skills or aspects of wellbeing that the standard treatment does not target, such as sleep or social rehabilitation. Augmentation can include pharmacological treatments, psychological treatments, or novel or emerging treatments such as exercise, acupuncture, or art therapy.

 

Augmentation of PTSD treatments is particularly appealing to both clinicians and trauma survivors for several reasons. Current evidence-based treatments for PTSD are primarily trauma-focussed with the primary ingredient of therapy being exposure to past traumas. These treatments can be challenging for individuals who are reluctant to confront their traumatic memories. Augmentation approaches can be used to help people engage with their trauma memories more easily. More examples of the challenges PTSD patients can face with PTSD are presented below, with possible solutions that augmentation approaches may provide.

 

Challenge Augmentation solution
Unwillingness or difficulty engaging with the traumatic memory
  • Decrease certain symptoms of PTSD such as avoidance
  • Increase distress tolerance
  • Improve overall cognitive resources
Cognitively taxing to process the trauma memory
  • Accelerate the fear extinction process
  • Improve trauma-related cognitive capacity
High levels of co-morbid problems can interfere with recovery
  • Improve sleep
  • Increase social support
  • Improve emotional regulation
A patient does not adequately respond to treatment
  • Combine two standard PTSD treatments
  • Add elements from other established treatments to standard PTSD treatment
  • Increase the frequency and/or intensity of treatment

 

While augmentation approaches are undoubtedly popular, there has been no research to synthesise the broad range of approaches that are available, and to establish their effectiveness. Our systematic review assessed high quality evidence for current interventions designed to augment first-line PTSD treatments (Metcalf et al., In press).

 

We searched for all randomised controlled trials that paired a guideline supported PTSD treatment (i.e., a first-line PTSD treatment such as prolonged exposure or cognitive processing therapy) with any psychological, pharmacological, or other treatment. A total of 34 randomised controlled trials (RCTs) were included, and these studies tested the efficacy of 28 different augmentation approaches. We clustered these 28 augmentation interventions into eight broad categories, based around the mechanism of augmentation, detailed in the table below.

 

Mechanism Possible therapeutic outcome
Global cognitive enhancers Improving overall cognitive/neurological functioning
Specific cognitive enhancers Improving particular aspects of cognition specifically related to trauma, such as attentional bias or accessing the trauma memory
Emotional distress reduction Improving coping with difficult emotions
Fear extinction Improving/speeding up the fear extinction process
First-line combinations Combining any first-line pharmacological or psychological treatments
Pharmaco polytherapy Combining a novel pharmacological treatment with a first-line pharmacological treatment
Sleep improvement Improving sleep deficits common in PTSD
Social rehabilitation Improving social functioning, commonly impaired in PTSD

Too much of a good thing?

The results were surprising in a number of ways. Firstly, the vast majority of studies (86 per cent) reported no additional positive effect on PTSD symptoms is achieved by the addition of an augmentation intervention compared to the first-line treatment alone. In other words, augmented PTSD treatments had no additional benefit. What was surprising was that the methods that intuitively should have been more powerful, such as augmenting a first-line treatment with another first-line treatment (typically pharmacotherapy), or adding highly supported elements from other psychological therapies, such as cognitive restructuring or imagery rescripting, had no effect. Importantly, in some instances, these approaches worsened PTSD outcomes relative to the standard treatment alone. We propose that these counter-intuitive findings are probably due to four important reasons:

  1. First-line treatments for PTSD are already effective, meaning anything additional has reduced variance to detect improvement.
  2. First-line treatments for PTSD are hard work, both cognitively and emotionally, as patients must learn a new method of engaging with their trauma memory. Any augmentation approach that requires further cognitive or emotional effort, or requires learning a new set of psychotherapeutic principles is taxing on the patient and may deplete or overload their ability to engage in the first-line treatment (Bryant et al., 2003).
  3. In order to keep total treatment time matched in an RCT protocol, the patient receiving augmentation may get less of the active first-line psychological treatment components to account for the time taken to deliver the other psychological therapy elements, diluting overall effectiveness (Marks et al., 1998).
  4. First-line psychological PTSD treatments arguably work by targeting the same dysfunctional cognitions, which means that the elements from other cognitive behavioural based therapies may be too similar to result in any additional meaningful change (Foa et al., 2005).

Feeding the fear memory

The core of effective first-line treatments follow fear extinction principles, in that gradual exposure to fear (e.g. the trauma memory) will uncouple the subsequent fear response from the memory and current day reminders or ‘triggers’ of the trauma memory. Understandably, it is appealing to trauma researchers and clinicians to use any augmentation approach that can accelerate this process to quicken the recovery of patients. Yet, a surprising finding in our review was that all pharmacological approaches designed to enhance fear extinction either worsened PTSD outcomes or showed no benefit. These approaches have been shown to be effective in anxiety disorders (e.g., Hoffmann et al., 2006), so what makes PTSD different?

 

Researchers have proposed if given too early, a pharmacological fear extinction intervention may simply consolidate or enhance the fear memory itself, perhaps via a stress interaction (Giustino & Maren, 2018), meaning the timing of the fear extinction agent is critical (Litz et al., 2012). Interestingly, the only fear extinction approach that showed positive findings was the non-pharmacological approach of exercise, which works via increasing brain-derived neurotrophic factor (BDNF) which in turn works to accelerate the fear extinction process (Powers et al., 2015).

What does work?

Positive results were shown primarily in the augmentation mechanism of general cognitive enhancers (i.e., the goal is to improve general cognitive function, such as executive functioning or neuroplasticity). Many of these approaches, such as acupoint stimulation and rTMS, require little cognitive effort on behalf of the participant, which may partially account for their efficacy when paired with a cognitively intense, trauma-focused intervention.

 

Further large-scale RCTs are needed to establish the efficacy of these promising augmentation approaches. Overall, more research in the area of personalised medicine is needed to better predict which individuals will respond best to what form of augmentation if at all. Future PTSD treatments will greatly benefit from expanding the sophistication of treatment algorithms to guide clinicians on how to select augmentation approaches to match the unique needs of individual patients in order to maximise recovery from trauma.

 

This article was first published on Division 12 website. Read the original article.