Nightmares and disruptive nocturnal behaviours that develop after traumatic experiences have long been recognized as having different clinical characteristics that overlap with other established parasomnia diagnoses. The inciting experience is typically in the setting of extreme traumatic stress coupled with periods of sleep disruption and/or deprivation. The limited number of laboratory-documented cases and symptomatic overlap with rapid eye movement sleep behaviour disorder (RBD) and posttraumatic stress disorder (PTSD) have contributed to difficulties in identifying what is a unique parasomnia. Hyperarousal, as opposed to neurodegenerative changes in RBD, is a component of TSD that likely contributes to overriding atonia during REM sleep (rapid eye movement sleep) and the comorbid diagnosis of insomnia. Disruptive nocturnal behaviours (DNB) consisting of excessive movements, autonomic hyperarousal, abnormal vocalizations and complex motor behaviours, and nightmares which are replays of traumatic experiences are frequently reported sleep disturbances in combat veterans and trauma survivors with and without posttraumatic stress disorder (PTSD). Despite their frequent occurrence, there is no established diagnosis that accurately encompasses these sleep disturbances. Nightmare disorder is reported in up to 80% of patients with PTSD. This diagnosis does not acknowledge the presence of the DNB that trauma survivors frequently report. Secondary REM behaviour disorder is reported to occur in patients with PTSD when REM without atonia (RWA) is present on a polysomnogram (PSG) and dream enactment behaviours are reported or are present on PSG; however, the onset of DNB and nightmares after an inciting traumatic event and the autonomic hyperactivity reported with trauma associated sleep disturbances are clinical and physiologic abnormalities that are not associated with REM behaviour disorder (RBD). In a review reported by Maher et al. (2006), 70 – 91% of patients diagnosed with PTSD reported difficulty falling or staying asleep. Nightmares were reported by 19 – 71% of patients, depending on the severity of their trauma. Interestingly, this study also found that sleep problems such as obstructive sleep apnea and sleep movement disorders are more common among trauma patients than in the general population. Why this may be the case is unclear but may be related to the physiological effects of prolonged hyperarousal. Movement disorders may be exacerbated by the chronic tension and frequent nightmares described above. When a person is under significant stress it is very difficult to fall into a deep sleep and this may lead to poor quality sleep in which the slightest sound can awaken the person.
The inimitable characteristics of trauma engendered sleep disturbances have led other authors to suggest that they should be regarded as a distinct nosological entity.
Credits: Trauma associated sleep disorder: A parasomnia induced by trauma by Vincent Mysliwiec; Matthew S.Brock; Jennifer L.Creamer; Brian M.O’Reilly; Anne Germain; Bernard J.Roth. 1055 Trauma Associated Sleep Disorder Revisited by Nathaniel Gordon, MD; Meagan Rizzo, MD; Brian Robertson, MD; Jacob Collen, MD. Trauma Associated Sleep Disorder: A Proposed Parasomnia Encompassing Disruptive Nocturnal Behaviors, Nightmares, and REM without Atonia in Trauma Survivors by Vincent Mysliwiec, M.D., F.A.A.S.M.; Brian O’Reilly, D.O.; Jason Polchinski, M.D.; Herbert P. Kwon, M.D.; Anne Germain, PhD; Bernard J. Roth, M.D.