Dr. Williams is the chief of sleep medicine at the Womack Army Medical Center in Fort Bragg, North Carolina, and an assistant professor in the Department of Medicine at the Uniformed Services University in Bethesda, Maryland. Dr. Collen is a staff pulmonologist, intensivist, and sleep disorders physician at the San Antonio Military Medical Center in Fort Sam Houston, Texas, and an assistant professor in the Department of Medicine at the Uniformed Services University. Dr. Mysliwiec is chief of pulmonary, critical care, and sleep disorders in the Medical Specialties Clinic at the 121 Combat Support Hospital in Korea. Dr. Wickwire is an assistant professor for the departments of psychiatry and medicine at the University of Maryland School of Medicine in Baltimore. Ms. Ryan is a health strategist and lead communicator and Dr. Lim is a psychologist, both in the Office of the United States Army Surgeon General in Falls Church, Virginia.
For patients who present with symptoms of TSD, a sleep study is recommended to evaluate for SDB as well as to characterize whether the patient has abnormal movements in REM sleep (lack of paralysis). There are currently no evidenced-based guidelines for treatment of this newly proposed sleep disorder. Behavioral and environmental modifications are the mainstay of treatment for individuals with any parasomnia. Obtaining an adequate quantity of sleep, avoiding triggers, and promoting a safe sleep environment are critical.
Substances that can lead to sleep fragmentation or impaired cognition, such as drugs and alcohol, should be avoided. Medical conditions that fragment sleep or cause nocturnal awakenings, such as sleep apnea, gastroesophageal reflux disease, and rhinitis should be treated to promote better sleep continuity.
When possible, medications with the potential to cause sleep fragmentation or disruption of normal sleep architecture should be reduced or discontinued. Weapons or objects that could be used as weapons should be removed from the bedroom, and padding should be placed on the sharp corners of furniture. Door and bed alarms, locks, and heavy curtains can minimize the risk of patients leaving the bedroom.
When these interventions are insufficient, medical therapy to suppress these events may be necessary. Some patients respond well to combined treatment with prazosin for nightmares and DNB, CBT for insomnia, and continuous positive airway pressure (CPAP) for OSA.39 Benzodiazepines, particularly clonazepam, may be effective for both slow-wave sleep parasomnias and RBD, but they should be used with caution in those with comorbid PTSD. Melatonin may also be effective, but there is a paucity of high-quality evidence supporting its use.
Obstructive Sleep Apnea
Another common sleep disorder that overlaps with PTSD is SDB. Obstructive sleep apnea is characterized by repetitive oxygen desaturations and arousals from sleep resulting from periodic upper airway collapse. Among middle-aged U.S. adults, about 9% of females and 24% of males have been estimated to have OSA, and rates increase with age and obesity.40 During the past decade, OSA in the military has risen dramatically, from 3,563 to 20,435 cases, with a 4-fold increase among those aged 20 to 24 years.17 Similar to the insomnia data, the increased rate of diagnosis during the recent wars in Southwest Asia coincides with an increase in the prevalence of traumatic brain injury (TBI) and PTSD. Additional reasons for the diagnostic increase may be heightened awareness of the diagnosis, increased availability of sleep disorders centers in the military, and even financial incentives for those undergoing a disability evaluation.
Obstructive sleep apnea is significantly more common in patients with PTSD compared with that in the general population, with rates of OSA ranging from 11.9% to 90%, depending on the study.41-43 Prevalence rates for OSA have been reported in several PTSD populations (violent crime, sexual assault, disasters, and combat). Military studies evaluating recent veterans have found OSA rates between 35% and 67%.44-46 In a recent study looking at SDB in those with PTSD, 53.8% had OSA (67.3% among those with polysomnograms).47 Although the other studies evaluated mixed populations of recent combat veterans, they were enriched for patients with PTSD.
Sleep disorders and PTSD have a “bidirectional” relationship.48 Sleep complaints preceding or temporally related to traumatic events increase the likelihood of subsequent mental health disorders, including PTSD.49-51 Sleep disorders are common in PTSD and are associated with symptoms of depression, relapse of depression, greater reductions in QOL, and suicide.52 Higher rates of OSA among patients who are not physically injured compared with the OSA rates of those with PTSD who also had physical injury (72.9% vs 38%) have also been seen, raising the possibility of different phenotypes of combat-related PTSD and a hypothetical role for premorbid OSA as a risk factor for PTSD.47
The pathophysiology linking SDB and PTSD is based on theories that poor sleep quality limits the ability to manage stress, promotes hyperarousal, confounds environmental stressors (trauma), and hinders the restorative qualities of sleep.49 Rapid eye movement sleep is believed to consolidate emotional memory, which may assist in recovery from traumatic events.53,54 Disrupted sleep architecture from OSA can diminish REM and hinder this process. Sleep fragmentation has been shown to cause upper airway instability and promote SDB.55 In addition, nighttime anxiety may induce hyperventilation with resultant hypocapnia, triggering apneic events.56 Taken together, disrupted sleep architecture, hyperarousal, respiratory instability, and nightmares may exacerbate one another and create a vicious cycle.57
Untreated OSA is associated with worse outcomes in PTSD. Continuous positive airway pressure has been shown to improve symptoms in this group.58-60 A study by Tamanna and colleagues evaluated clinical outcomes related to CPAP use, demonstrating improvements in nightmares, daytime sleepiness, and PTSD symptom severity with increasing adherence.61 Unfortunately, patients with PTSD generally have suboptimal medical adherence, and CPAP adherence decreases in psychiatric disease.62,63 Two recent studies have shown significantly lessened adherence in patients with both PTSD and OSA (compared with OSA alone), in both younger and older veteran populations.64,65 Limited insight and atypical clinical presentations of OSA also limit patient acceptance of treatment. Continuous positive airway pressure usage is decreased by comorbid insomnia, common in PTSD.66 Similarly, nightmares, mask discomfort, air hunger (the feeling of not being able to get a satisfying breath), and claustrophobia have all been associated with poor CPAP adherence in patients with PTSD.