Reducing intrusive memories after trauma via a brief cognitive task intervention in the hospital emergency department: an exploratory pilot randomised controlled trial

Abstract

Intrusive memories are common after trauma, and can cause significant distress. Interventions to prevent/reduce the occurrence of this core clinical feature of posttraumatic stress disorder are needed; they should be easy to deliver, readily disseminated and scalable. A novel one-session intervention by Iyadurai et al. 2018, Molecular Psychiatry, resulted in intrusion reduction over the subsequent week. Its feasibility in a different setting and longer-term effects (>1 month) need investigation. We conducted an exploratory open-label pilot randomised controlled trial (RCT) to investigate the feasibility and effects of a brief behavioural intervention to reduce intrusive memories in trauma-exposed patients in a Swedish hospital emergency department (ED). Participants (final N = 41) were randomly allocated to either intervention (including memory reminder cue then visuospatial cognitive task “Tetris” with mental rotation instructions) or active control (podcast) condition within 72 h of presenting to the ED (both conditions using their smartphone). Findings were examined descriptively. We estimated between-group effect sizes for the number of intrusive memories post-intervention at week 1 (primary outcome) and week 5 (secondary outcome). Compared to the control condition, participants in the intervention condition reported fewer intrusive memories of trauma, both at week 1 and week 5. Findings extend the previous evaluation in the UK. The intervention was readily implemented in a different international context, with a mixed trauma sample, with treatment gains maintained at 1 month and associated with some functional improvements. Findings inform future trials to evaluate the capacity of the cognitive task intervention to reduce the occurrence of intrusive memories after traumatic events.

Selectively Interfering With Intrusive but Not Voluntary Memories of a Trauma Film: Accounting for the Role of Associative Memory

“…One advantage is that this simple cognitive-task approach may be developed in a manner to maximize safety and minimize distress while doing the intervention, which is important given that particular clinical approaches have been shown to worsen trauma symptoms (Rose et al, 2002) and that approaches that require talking about the trauma in detail are not tolerated by all patients (Hoge & Chard, 2018;National Institute for Health and Clinical Excellence, 2018). Initial proof-ofconcept studies using the reminder-plus-Tetris procedure are promising in preventing intrusive symptoms within the first week after trauma (Horsch et al, 2017;Iyadurai et al, 2018;Kanstrup, Singh, et al, 2021) and in reducing more persistent intrusive symptoms (Iyadurai et al, 2020;Kanstrup, Knotio, et al, 2021), including in established PTSD (Kessler et al, 2018). In these translation studies, the necessary reminder cue ( James et al, 2015, Experiment 2;Lau-Zhu et al, 2019, Experiment 3) was adapted to each clinical context, with variations such as a brief hotspot verbal reminder (Iyadurai et al, 2018;Kanstrup, Kontio, et al, 2021;Kanstrup, Sing, et al, 2021), a context reminder (Horsch et al, 2017), or a written reminder (Kessler et al, 2018).…”

“…As in Lau-Zhu et al (2019, Experiments 1-3), participants were randomly assigned to a cognitive-task-interference group (reminder plus Tetris) or a control no-interference group (reminder only) 30 min after they viewed a trauma film. A pre-Tetris reminder was included in a successful real-world clinical translation of this interference procedure (Iyadurai et al, 2018;Kanstrup, Singh, et al, 2021), critically shown to be necessary in the laboratory to observe interference on intrusions (Lau-Zhu et al, 2019). Indeed, absence of this reminder component was associated with a lack of interference effect (Brühl et al, 2019).…”

Digitalizing a Brief Intervention to Reduce Intrusive Memories of Psychological Trauma for Health Care Staff Working During COVID-19: Exploratory Pilot Study With Nurses

“…The number of intrusive memories of the traumatic events was assessed with a digital adaptation of the pen-and-paper diary used in our previous work [28]. Instead of ticking a box for each intrusive memory during four time periods (morning, afternoon, evening, and night) on a paper diary, participants received four digital links per day (after each period of the day had passed) via SMS text message and email from the electronic platform SmartTrial [40] version 2020.1.…”

“…Early studies have shown that the intervention may prevent intrusive memory occurrence in patients soon after trauma [29,30] (eg, by 62% compared to attention placebo control in motor vehicle accident survivors [29]). In a study with patients with more diverse trauma types in a Swedish emergency department, participants in the intervention condition reported 48% fewer intrusive memories compared to attention placebo control at week 1 following the intervention and 90% fewer at week 5 [28]. Promising results in terms of established intrusion reductions have also been shown in small-scale case series research with refugees [32], patients with complex PTSD [31], and in a person with bipolar disorder and PTSD [33].…”

“…The intervention can be used on the same day the traumatic event occurred (day 1 protocol) [28][29][30]. For intrusive memories from older traumatic events [31,32], there are seemingly minor but important procedural differences including the type of memory reminder instructions and the time between the memory reminder and the task (see Visser et al [26]).…”