Circadian Influence on Prolonged Exposure Therapy for PTSD

Who can take part

• a diagnosis of PTSD as defined by DSM-5, with a minimum CAPS severity score of 26, a minimum PCL-5 score of 31, or a score of 2 or above on CAPS-5 Item B2 (concerning distressing dreams)
• interest in starting a course of PE
• availability for appointments at that will either begin from 07:00 to a time no longer than 2 hours past their customary rise time, or to the last treatment session of the day beginning at 16:00 or later
• Age range of 18-70
• A Morningness-Eveningness Questionnaire (MEQ) score above 25
• Non-exclusionary psychotropic medications must have been stable for 3 weeks prior to Screening/Assessment with intention to remain stable throughout participation

Who cannot take part

• current participation in trauma-focused cognitive-behavioral therapy (e.g., Cognitive Processing Therapy, Written Exposure Therapy, Eye Movement Desensitization and Reprocessing Therapy)
• prior treatment with an adequate dose of PE (i.e., 8 or more sessions) to the traumatic event that would be the index trauma for treatment in the study
• methadone or suboxone maintenance therapy for past opioid addiction
• current or past history of bipolar I disorder, schizophrenic or other psychotic disorders,
• current organic brain disorder including moderate to severe traumatic brain injury
• factitious disorder or malingering
• current moderate or severe substance use disorder with symptoms present within the past three months
• diagnosed moderate to severe sleep apnea, narcolepsy, periodic limb movement, or restless legs syndrome that result in daytime sleepiness indicated by Epworth Sleepiness Scale (ESS) above 10
• evidence of clinically significant hepatic or renal disease or any other acute or unstable medical condition that might interfere with safe conduct of the study
• diagnosis of Cushing's disease, Addison's disease or use of medications that target cortisol directly such as those used to treat Cushing's disease [ketoconazole, mitotane (Lysodren), metyrapone (Metopirone), and Mifepristone (Korlym, Mifeprex)], those used to treat Addison's disease [Hydrocortisone (Cortef), prednisone or methylprednisolone], as well as cortisone or dexamethasone
• pregnant or planning to become pregnant in the next four months at time of screening [if a participant does become pregnant during study procedures, the situation will be reviewed on a case-by-case basis and the participant's wishes will be considered in deciding whether the participant will continue with the study or withdraw.]
• active risk of harm to self or others
• having no memory of their traumatic event
• daily use of benzodiazepines
• persons who would habitually awaken so early that more than 2 h would elapse before a morning PE session could occur; or those who engage in habitual shiftwork or transmeridian travel