Examining Insomnia and PTSD Over Time in Veterans in Residential Treatment for Substance Use Disorders and PTSD.

: Insomnia occurs in 66-90% of individuals with posttraumatic stress disorder (PTSD) and 36-72% of individuals with substance use disorder (SUD). Individuals with both PTSD and SUD are more likely to have insomnia than individuals with only one disorder. Insomnia is associated with poorer treatment outcomes for both PTSD and SUD, increased daytime symptomology for PTSD, and increased relapse for SUDs. As such, it is important to understand how sleep affects PTSD treatment among patients dually diagnosed with SUD and how sleep changes over time in a residential unit for SUDs. : Participants were 40 veterans with comorbid PTSD and SUD in a 28-day Substance Abuse Residential Rehabilitation Treatment Program (SARRTP) PTSD track. : Analyses used mixed models with Time (baseline, posttreatment, 3-month follow-up) to examine PTSD and insomnia severity over time. : Results of the longitudinal mixed model showed that PTSD symptoms improved over time but that insomnia symptoms did not. Although baseline insomnia did not affect follow-up PTSD symptoms, individuals with greater insomnia severity at the start of treatment had more severe baseline PTSD symptomatology. However, there was not an interaction of insomnia and PTSD severity over time such that baseline insomnia did not affect PTSD trajectories. : These findings are consistent with the PTSD outpatient treatment findings and further adds evidence that insomnia is unremitting without direct intervention. Given the relationship insomnia has with PTSD severity, SUD, and relapse, directly targeting insomnia may further help improve both PTSD and SUD treatment outcomes.