0423 The Role of Fear of Sleep in Cognitive Behavioral Therapy for Insomnia and Cognitive Processing Therapy

Abstract Introduction Fear of sleep (FoS) is linked to symptoms of PTSD. Additionally, cognitive behavioral therapy for insomnia (CBTi) can reduce FoS. Utilizing data from a randomized controlled trial of CBTi followed by Cognitive Processing Therapy for PTSD (CPT), this secondary data analysis sought to examine the relationship between FoS and PTSD symptoms, and how FoS is impacted by CBTi, in individuals exposed to interpersonal violence with PTSD. Additionally, we sought to extend the literature by examining whether FoS predicts the effect of subsequent CPT on PTSD severity or if CPT further reduces FoS. Methods A sample of 83 participants were randomly assigned to either receive sequential delivery of four weekly sessions of CBTi, which included modules to address FoS, followed by 12 weekly sessions of CPT (Group 1: CBTi+CPT) or receive four weekly phone check-ins (CTRL) followed by CPT (Group 2: CTRL+CPT). Participants were assessed at baseline (T1), after CBTi/CTRL (T2), and after CPT (T3). Relevant measures included the Fear of Sleep Inventory (FoSI) and Clinician Administered PTSD Scale (CAPS). Analyses included correlations, mean differences tests, and regression-based analyses. Results At T1 FoSI and CAPS were positively correlated (r = 0.47, p < 0.001). At T2 a significant reduction in FoSI scores was observed after CBTi/CTRL for Group 1 (t = 4.81, p < 0.001), but not Group 2, and a significant difference in FoSI scores between Group 1 and Group 2, all while controlling for baseline differences (F (1, 80) = 3.99, p < 0.05). Lastly, for the entire sample lower T2 FoSI scores predicted lower T3 CAPS scores (B = 0.42, p < 0.01) and FoS was not further reduced following CPT. Conclusion Results replicate previous work by demonstrating a positive relationship between FoS and PTSD severity. Additionally, FoSI was significantly reduced after CBTi. Lastly, lower levels of FoS predicted reduced PTSD symptoms following CPT, although CPT was not associated with significant reductions in FoS. Results highlight that CBTi that explicitly addresses FoS may reduce FoS, and findings also suggest that effectively reducing FoS prior to PTSD treatment may improve treatment outcomes. Support (if any) NIH/NINR R01 NR013909; VA Center of Excellence for Suicide Prevention