0497 Obstructive Sleep Apnea Prevalence in a Young Mixed Trauma Population with Post-traumatic Stress Disorder Symptoms

Abstract Introduction Disturbed sleep appears to play a role in post-traumatic stress disorder (PTSD) development and maintenance. The prevalence of obstructive sleep apnea (OSA, as defined as an AHI>5 events/hr) has been reported to be up to 75% in individuals with PTSD (Zhang 2017). Most prior studies investigating OSA prevalence in PTSD have been conducted in military populations, who commonly have other risk factors for OSA such as being male, middle-aged and having high rates of substance use disorders. The aim of this study was to determine whether OSA is more common in individuals with PTSD symptoms exposed to non-military traumas as compared to individuals without PTSD symptoms. Methods 125 participants interested in completing a sleep study completed a screening questionnaire measuring previous Criterion A trauma exposure (Life events checklist) and PTSD symptoms (PTSD symptom checklist for DSM-5, PCL-5), along with alcohol use and demographic information. A sub-set were recruited for a standard overnight polysomnography either in the sleep laboratory (Grael, Compumedics), or at home (Siesta, Compumedics). Sleep studies were scored blinded to questionnaire data by an independent sleep technician. Three symptom severity groups were compared, individuals with Likely PTSD (PCL-5 >33 and Criterion A trauma exposure) Sub-Syndromal PTSD (PCL-5 15-33 and Criterion A trauma exposure) or No-PTSD (PCL-5 < 15 and no intrusive symptoms). Results 45 participants (31 female; aged 18-48 years) completed the polysomnography. 11 had likely PTSD, 10 Sub-Syndromal PTSD and 23 had No-PTSD. The 3 groups were comparable in age (25±7 years), sex (68% women) and BMI (24.2±4.5 kg/m2). In total, 6 participants had AHI >5 events/hr; 3 in the Likely PTSD group, 2 in the Sub-Syndromal group and 1 in the No-OSA group. The mean AHI did not differ between groups (Likely PTSD = 5.1±7.7, Sub-Syndromal PTSD = 4.0±6.7, No-PTSD = 2.2±4.4 events/hr, p=.64). Conclusion Although the a priori sample size (n=26 in each group) has not yet been reached, these preliminary data indicate that the prevalence of OSA in a young mixed-trauma PTSD population is unlikely to be as high as has been observed previously. PTSD may only increase the risk for OSA in older/heavier individuals. Support (if any) University of Melbourne.