Imagery rescripting and imaginal exposure for nightmares efficacy and mechanisms of change

Objectives/Instruction: Nightmares can be effectively treated with cognitive‐behavioral therapies. It remains elusive which therapeutic elements are responsible for the beneficial effects on nightmare symptoms. Imagery rescripting (IR) and imaginal exposure (IE) are commonly identified as active treatment components of nightmare therapies. With this randomized controlled trial, we compared IR and IE as individual treatments to a wait‐list (WL) condition to determine whether these particular therapeutic elements ameliorate nightmare symptoms and whether mastery and tolerability mediated the effects.
Methods: In this trial we randomized 104 patients with a primary DSM‐5 diagnosis of nightmare disorder into an IR, IE, or wait‐list control group. In the intervention conditions all participants received three weekly 60 min individual treatment sessions. The treatment conditions only consisted of IR or IE and did not both comprise of treatment elements such as extensive psycho‐education, relaxation and safe‐place exercises, or nightmare journals. Nightmare distress
was assessed with the Nightmare Distress and Impact Questionnaire (NDIQ; range 0–36). Mediators were assessed weekly with VAS scales. Tolerability (0–100): “I think that I can tolerate the emotions elicited by my nightmares.” Mastery (0–100): “I think that I am in control of the content of my nightmares.”
Results: Results showed that compared to WL, both interventions effectively reduced nightmare frequency, dir-wl = 74; die-wl = 0.70 and distress dir-wl = 0.98; die-wl = 1.35 in a sample that predominantly consisted of idiopathic nightmare sufferers. The effects of IR and IE were comparable to those observed for other psychological nightmare treatments. Initial effects at post‐treatment were sustained at 3‐ and 6‐months follow‐up. Distress was mediated by mastery in the rescripting condition (but not by tolerability). Distress was mediated by tolerability in the exposure condition (but not by mastery).
Conclusions: IR and IE both seem to be efficacious treatment components of nightmare therapies. Additional research is needed to directly compare IR and IE among both idiographic and posttraumatic nightmare sufferers with respect to treatment expectancy, acceptability, and effectiveness. Even though IR and IE for nightmares seem to produce similar therapeutic effects, the results of this study suggest that IR and IE tap into different underlying processes.
Disclosure: Nothing to disclose.