CPAP ADHERENCE AND RESPONSE TO COGNITIVE PROCESSING THERAPY FOR PTSD IN VETERANS WITH OBSTRUCTIVE SLEEP APNEA

Abstract Introduction Cognitive processing therapy (CPT) is a recommended first-line psychotherapy treatment for veterans with PTSD. Veterans with PTSD are at higher risk for sleep disorders including obstructive sleep apnea (OSA), and there is evidence that OSA can exacerbate PTSD and vice versa. Several studies have shown that CPAP use is associated with improvement in PTSD symptoms. CPT is an effective, yet time and resource intensive treatment option, making it critical to identify potential health factors impacting its efficacy. This retrospective chart analysis of veterans diagnosed with OSA and PTSD evaluated the effect of CPAP adherence on response to CPT. Methods Medical records of patients seen in a VA Health Care System were reviewed to identify veterans diagnosed with OSA and PTSD that received between 1-12 sessions of CPT with documented weekly PTSD Checklist for DSM-5 (PCL-5) scores, Patient Health Questionnaire-9 (PHQ-9) scores, and were issued a CPAP machine for OSA. Data collected included demographics, CPAP adherence (mean CPAP use, % days with greater than 4 hrs./night of CPAP use, mean residual apnea hypopnea index, mask leak), and PTSD symptoms (PCL-5 and PHQ-9 scores). For each outcome, we estimated a linear mixed-effects model; models for PCL-5 allowed heterogeneous residual variances for each veteran. Results This study identified 25 veterans receiving CPT for PTSD with access to a CPAP machine for OSA. The median age of patients was 43 years, median BMI was 35.6, and median residual AHI was 2.4. Patients received CPT for a median duration of 11.0 weeks. There was significant improvement in weekly PCL-5 and PHQ-9 scores over the course of CPT (both p < .001). CPAP adherence of at least 4 hrs./night for ≥70% of days did not significantly impact PCL-5 and PHQ-9 scores during CPT. Residual AHI and mask leak were not associated with PTSD symptoms during CPT. Conclusion While CPAP nonadherence appears to be a potential contributing factor to the reduced effectiveness of evidence-based treatments for veterans with PTSD, our study revealed significant improvement in PTSD symptoms during CPT regardless of CPAP adherence. Given the retrospective nature and small sample size of this study, further research is needed to expand on these findings. Support (If Any)