Cognitive behavioral therapy for insomnia treatment attrition in patients with weekly nightmares

Study Objectives: This study's objective was to evaluate the effect of nightmares (NMs) on attrition and symptom change following cognitive behavioral therapy for insomnia (CBT-I) treatment using data from a successful CBT-I randomized controlled trial delivered to participants with recent interpersonal violence exposure. Methods: The study randomized 110 participants (107 women; mean age: 35.5 years) to CBT-I or to an attention-control group. Participants were assessed at 3 time periods: baseline, post-CBT-I (or attention control), and at time 3 (T3) post-cognitive processing therapy received by all participants. NM reports were extracted from the Fear of Sleep Inventory. Participants with weekly NMs were compared with those with fewer than weekly NMs on outcomes including attrition, insomnia, posttraumatic stress disorder, and depression. Change in NM frequency was examined. Results: Participants with weekly NMs (55%) were significantly more likely to be lost to follow-up post-CBT-I (37%) compared with participants with infrequent NMs (15.6%) and were less likely to complete T3 (43%) than patients with less frequent NMs (62.5%). NMs were unrelated to differential treatment response in insomnia, depression, or posttraumatic stress disorder. Treatment with CBT-I was not associated with reduced NM frequency; however, change in sleep-onset latency from post-CBT-I to T3 predicted fewer NMs at T3. Conclusions: Weekly NMs were associated with attrition but not a reduced change in insomnia symptoms following CBT-I. NM symptoms did not change as a function of CBT-I, but change in sleep-onset latency predicted lower NM frequency. CBT-I trials should screen for NMs and consider augmenting CBT-I to specifically address NMs.