William Brim, PsyD, and Diana C. Dolan, PhD, CBSM
Sergeant John Evertired is a 32 year-old married Caucasian male in the Army National Guard. He is a Construction Engineer on duty and works for a highway and bridge construction company as a civilian. Sgt. Evertired previously served four years on Active Duty in the Army during which he had one deployment to Iraq in 2004. He left active duty following the deployment, attended some college and worked full-time driving heavy equipment and building roads. In 2007 he joined the Army National Guard and was deployed, again to Iraq, at the tail end of the Surge in 2008. He was indirectly exposed to combat and its aftermath during his two deployments to Iraq but did not see direct combat action. In 2011-12 his company was deployed for 12 months to Afghanistan. On this deployment while on a route improvement mission, he was caught in an Improvised Explosive Device (IED) ambush in which the vehicle in front of his truck and a following vehicle were hit. Several members of his unit were killed or seriously injured.
Sgt. Evertired experienced problems related to the quantity and quality of sleep as far back as his first deployment but he never felt that it was significant enough to warrant seeking any type of treatment. After his second deployment to Iraq, he again reported having problems with sleep that gradually worsened over the two years leading up to his deployment to Afghanistan. He tried several over the counter medications and supplements, including Sominex, Tylenol PM, and melatonin, with limited improvement. By the time of his last deployment in late 2011, he stated that sleep issues were causing problems for him socially and occupationally, and that just prior to being activated he had gotten in trouble at his civilian job for falling sleep behind the wheel of a bulldozer while on break. Since his return from Afghanistan, he has been treated for PTSD with some success but continues to suffer with sleep problems and moderate to severe daytime fatigue. He sought treatment with another civilian provider that “didn’t work out” and has decided to give therapy “one last chance before giving up.”
Service members generally get less sleep than their civilian counterparts, with one study suggesting that seventy-two percent of previously deployed Army soldiers report typically getting less than six hours of sleep a night (Luxton, 2011) compared to seventy-two percent of civilian adults reporting getting seven or more hours per night (Krueger & Friedman, 2009). Adding to the concern related to short sleep duration of military members is the impact of deployment, often repeated deployment, and exposure to trauma and injury that has been well documented over the years of the wars in Iraq and Afghanistan. In fact, the most common complaint on post deployment surveys of Service members returning from deployment is related to the quality or quantity of sleep. Today, if you work with service members or veterans you have probably come to expect hearing about sleep concerns. However, many psychologists have little or no training specific to the assessment and treatment of sleep disorders that would prepare them to work effectively with Sgt. Evertired. This article will briefly discuss sleep-wake disorders in general with a focus on addressing the sleep disturbances that are most common in military members and veterans, describe the importance of a thorough assessment of sleep disturbances, and provide a brief overview of the effective treatments currently available for these most common sleep problems in the military population.
The Diagnostic and Statistical Manual of Mental Disorders (DSM) made several significant changes from the DSM-IV (APA, 1994) to the DSM-5 (APA, 2013) in both the classification and diagnostic criteria for many of the sleep-wake disorders. The DSM-5 sleep-wake disorders category now encompasses 10 disorders or disorder groups, including insomnia disorder, narcolepsy, breathing related sleep disorders, restless leg syndrome and nightmare disorder (see figure 1). The classifications in the DSM-5 are organized for easier differential diagnosis and to clarify when a referral to a sleep specialist may be warranted. It is geared towards general mental health and medical clinicians rather than sleep medicine specialists and includes new evidence related to biological validators for narcolepsy and breathing related sleep disorders that likely warrant a formal sleep study. A few of these changes are highlighted below.
One of the most significant changes is based on the DSM-5 mandate for concurrent specification of coexisting medical and mental conditions. Because of this mandate, sleep disorders related to another mental disorder or a general medical condition have been removed. This change reflects a general recognition in the field that sleep disturbances and comorbid mental and/or medical conditions often have bidirectional and interactive effects. It also highlights the fact that effective treatment of an “underlying” medical or mental condition often does not effectively address the sleep disturbance, which will often require independent clinical attention. A notable example is the diagnosis of Primary Insomnia has been changed to Insomnia Disorder to avoid the need to differentiate primary from secondary insomnia based on a potentially murky etiology.
The specific criteria for insomnia disorder have changed and now include a predominant complaint of dissatisfaction with the sleep quality or quantity associated with at least one of the following; difficulty falling asleep or maintaining sleep and/or with the addition of the symptom of early morning awakening. In the DSM-5 the sleep difficulty occurs at least 3 nights a week for at least 3 months. Perhaps most relevant to a military population is the new criteria that the sleep difficulty occurs despite adequate opportunity for sleep, which may not exist in a deployed setting for many Service members. The Breathing-Related Sleep Disorders category is now divided into three distinct disorders: Obstructive Sleep Apnea Hypopnea, commonly abbreviated as OSA; central sleep apnea; and sleep-related hypoventilation. These changes reflect improved understanding of the underlying pathophysiological mechanisms associated with the different disorders and the relevance to treatment planning for each. For the diagnosis of OSA, there must be evidence from an overnight sleep study, or polysomnograph (PSG), of:
- at least 5 obstructive episodes per hour of sleep associated with either breathing disturbance, snoring, or gasping during the night, or
- daytime sleepiness, fatigue, or unrefreshing sleep not due to another medical or mental condition, or
- evidence of 15 or more obstructive episodes per hour of sleep regardless of accompanying symptoms.
A persistent or recurrent pattern of sleep disruption that is primarily due to an alteration of the circadian system or to a misalignment between endogenous circadian rhythm and the sleep-wake schedule that causes excessive sleepiness or insomnia and significant distress are the criteria for the Circadian Rhythm Sleep-Wake Disorders category. There were significant changes to the subtypes of Circadian Rhythm Sleep-Wake disorders in the DSM-5. This category now includes advanced sleep phase syndrome, irregular sleep-wake type and non-24-hour sleep-wake type, while the subtype of jet lag type has been removed. The most common circadian rhythm sleep-wake disorder, especially in young adults of military age, remains the Delayed Sleep Phase Type in which there is a pattern of delayed sleep onset and awakening times with an inability to fall asleep and awaken at desired or acceptable earlier times.
A thorough review of all of the changes to the Sleep-Wake Disorders is beyond the scope of this article but is highly recommended for psychologists who regularly asses sleep disorders in your practice.
Sgt. Evertired reported that about six months ago he had been convinced by his wife to “do something about his irritability and sleep problems.” He had seen a provider who gave him “some sort of BS list of things to do to help his sleep…something about sleep hygiene” but that he found most of the items unhelpful. He felt the therapist was more interested in his combat experience and occasional nightmares and “couldn’t listen to the fact that I was over that.” He has since resorted to having an occasional “beer or two” to fall asleep and more often than not sleeps on the couch so he does not disturb his wife. Problems continue to escalate at work, and he has been in several fights on his civilian job and was reprimanded on a recent drill weekend when he did not show up on time.
Not surprisingly, the same types of sleep disorders common among civilian populations are also common in military populations, although different contributing factors may be involved. For example, a review of sleep studies performed at a military treatment facility found that OSA and insomnia were the two most common sleep diagnoses (Mysliwiec et al, 2013); additionally, military members may also have other sleep problems including circadian rhythm disorders, nightmares, and sleep changes due to Traumatic Brain Injury (TBI). A psychologist treating a military patient should consider these disorders when conducting an assessment and developing a case conceptualization.
Obstructive sleep apnea can frequently cause complaints of sleep difficulties, particularly reports of poor sleep quality and fragmented sleep. Risk factors for OSA include male gender, middle-aged or older, and a heavy build. Similarly, service members are primarily male with an average of 29 years (35 for officers) among Active Duty and 32 years (40 for officers) among Reservists/Guard members (2012 Demographics Report: Profile of the Military Community). When working with a military member who has sleep problems along with symptoms such as snoring or excessive daytime sleepiness, psychologists should consider the possibility of recommending a sleep study to rule out OSA. Among those Service members referred for a sleep study by their primary care provider or mental health provider, slightly more than half were diagnosed with OSA from mild to severe severity (Mysliwiec et al, 2013), and among veterans referred for a sleep study in one VA Hospital, slightly more than three-quarters were diagnosed with OSA (Samson et al, 2012). OSA constitutes a potentially serious condition for military members, since excessive daytime sleepiness can impair performance in dangerous environments, such as during a deployment or while working with firearms.
Insomnia is cited by military members as a frequent sleep problem. During a deployment, a military member may have to make substantial changes to ideal sleeping patterns that can increase the risk for insomnia upon returning home. Some of these changes to patterns include sleeping at random times or in small time periods, sleeping in a crowded, brightly lit areas, sleeping on the ground, or trying to sleep despite loud noises, including rocket and mortar fire. One anonymous, online survey of 375 Service members and veterans several years after deployment found that more than 45% reported they took longer than 30 minutes to fall asleep and 56% reported that they spent 15% or more of the night lying in bed awake (Plumb, Peachey & Zelman, 2014). However, given the high workload and levels of stress among military members in garrison to cover for the reduced manning due to deployments, insomnia in our experience is a frequent complaint regardless of whether or not a service member has deployed. Compared to the 8% of the US population who obtains less than 5 hours of sleep each night, 42% of military members in one study reported the same, although some military members’ short sleep durations may result from work schedules or other behavioral factors instead of primary insomnia (Mysliwiec et al, 2013).
Circadian rhythm disorders can stem from or be exacerbated by the hectic work schedules involved in military life. Military members often work long hours, have to report very early in the morning for duty, and get assigned to rotating work schedules. One example is the “Panama schedule” used by some units where every 2-3 days the worker switches from on to off duty and rotates the timing of the work shift from day to night every four weeks. Shift work is also more likely during deployments, and deployed service members on night shifts tend to have more difficulty falling and staying asleep (Peterson et al, 2008), which may persist after returning home. Regarding sleep phase disorders, in the military environment where early rising is expected, patients with advanced sleep phase tendencies may perform well, but those with a preference for a much later bed and wake time tend to have problems adapting and often seek treatment believing they have insomnia when a delayed sleep phase disorder is present instead.
Nightmares, whether related to a full-blown mental health disorder such as PTSD or to exposure to trauma in general, comprise a number of sleep-related complaints among military members. Despite efforts among the military branches to reduce stigma for seeking mental health-related help, service members and veterans may still be more willing to disclose and seek treatment for sleep difficulties, such as insomnia caused by nightmares, as opposed to first addressing any underlying trauma.
Interestingly, while there appears to be no difference in the prevalence of OSA among military members with PTSD as compared to those without PTSD, some research has suggested a link between OSA severity and PTSD severity (van Liempt et al, 2011). This link may relate to nightmares, where the fragmented sleep in OSA may increase awareness of PTSD symptoms such as nightmares, so that treating the OSA may improve PTSD severity. Unfortunately, nightmares relate to lower adherence to OSA treatment (El-Solh et al, 2011), which means that nightmares and other sleep problems can develop into a negative cycle.
Sleep difficulties in military members may also stem from a traumatic brain injury. Because sleep is regulated by the brain, a brain injury, even a relatively mild one, may temporarily disrupt sleep. Many patients with sleep disruption from a TBI will complain not only of insomnia but also of excessive daytime fatigue. On top of difficulty regulating sleep and wakefulness, one group of veterans who reported a TBI with loss of consciousness (a moderate TBI) were found to be at a four-time greater risk for nightmares even when controlling for potential PTSD symptoms (Gellis et al, 2010). Multiple TBIs may further worsen the likelihood of developing sleep problems; whereas nearly a quarter of military members with TBI have insomnia, nearly half of those with more than one TBI have insomnia (Bryan, 2013). Since military members who have deployed may have been exposed to blast or combat injuries that did not result in visible injury, it is possible that patients presenting with sleep-related complaints may actually have a TBI that warrants follow-up.
Sgt. Evertired reported that he had previously been diagnosed with PTSD related to the trauma exposure in Afghanistan. He was treated by a military psychologist who had him “revisit my memory of the trauma over and over and listen to tapes of the trauma memory. He also made me go out a do things I had been avoiding like driving through town until it didn’t bother me as much”. Sgt. Evertired denied currently experiencing any avoidance symptoms, negative cognitions associated with the trauma or hyper-vigilance. He did acknowledge some irritable mood and occasional anger outbursts and he stated that he does still have nightmares related to the trauma about 2-3 times a month that interfere with his sleep. According to Sgt. Evertired, his wife says that his sleep seems very light and restless and that he seems to be snoring and almost waking up a lot during the night. Sgt. Evertired stated that he did not know that he snores but acknowledged that he does wake up during the night and sometimes cannot get back to sleep.
Any one of the sleep disorders previously described, and some not covered in this article, can contribute to difficulty falling and staying asleep. If the patient’s sleep difficulties do not stem from primary insomnia, treating the underlying cause is the best course of action before addressing the sleep difficulties directly. For this reason, we recommend a thorough assessment of the patient’s symptoms and medical history prior to treatment. The primary goal of a thorough assessment of sleep is differential diagnosis. Specifically, are there conditions that might require a referral to a sleep specialist or primary care provider, such as OSA or Restless Leg Syndrome, and to determine if Cognitive Behavioral Therapy for insomnia would be appropriate. Assessment measures should be retrospective and may include the Insomnia Severity Index (Morin, 1993, a Dysfunctional Beliefs and Attitudes about Sleep Scale (Morin, 1993 and an assessment of daytime impact such as the Epworth Sleepiness Scale (Johns, 1991) and daily recording in a sleep diary. The clinical interview then covers a history of sleep patterns and preferences, sleep-relevant behaviors, a functional analysis to identify factors that improve or worsen sleep, an assessment of the sleeping environment, information related to military history, such as deployments and duty hours, and a medical and psychiatric history (see box 1). Importantly, clinicians should screen for potential sleep disorders other than insomnia and may use additional screeners such as the STOP screen for OSA and the Restless Leg Syndrome Rating Scale for RLS as indicated.
If the evaluation suggests that the patient has OSA or an underlying medical condition, a referral to a sleep specialist is warranted before initiating a trial of behavioral treatment. Not only is behavioral care likely to be significantly less effective in these cases, it can also impact the patient’s health. In the case of OSA, a delay in appropriate medical care can sometimes perpetuate severe breathing, cardiovascular, and cognitive problems. Once treated, if patients still report sleep difficulties, behavioral treatment can resume as an adjunct to medical care.
A thorough assessment of Sgt. Evertired’s sleep, including a functional analysis and use of the STOP screener clearly suggest that a referral for a sleep study is indicated. Sgt. Evertired reported that in addition to his spouse’s report of relatively recent onset of loud snoring and his experience of excessive daytime fatigue, he has also gained weight and been told by his primary care doctor that he has borderline high blood pressure.
Depending on the sleep disorder, behavioral treatment, medical treatment, or a combination approach may be indicated. For insomnia, cognitive-behavioral therapy known as CBT-I has increasingly been recognized as the treatment of choice, especially for persistent insomnia. CBT-I includes multiple components, such as sleep restriction, stimulus control, relaxation, and cognitive interventions, and has been shown to significantly reduce not only time to fall asleep and the number/length of awakenings, but also to improve sleep quality (Kryger et al, 2011 ). Anecdotally, one of us (DD) had a patient return to normal sleep parameters in less than two months after having insomnia for 42 years! Among veterans, CBT-I has been found to have similar outcomes for measures of sleep quality and quantity as civilian studies in as few as eight to 10 sessions (Perlman et al, 2008).
Medication options for insomnia are also largely effective and safe. Non-benzodiazepine hypnotics, including Ambien, Lunesta, and Sonata, have been approved specifically for sleep difficulties, as well as a small number of benzodiazepines. While medications generally result in similar reductions in sleep onset latency and time awake in bed at night and longer total sleep times than behavioral treatments, they do not have as long-term an effect (Kryger et al, 2011). Medications are frequently used to manage the transient sleep difficulties found on deployment and in other military settings, so military members may have greater awareness of medication options than behavioral treatment.
For OSA, the gold standard of treatment is known as PAP, or positive airway pressure. While there are multiple variations available, essentially the idea of PAP therapy is to prevent the airway from collapsing at night using air pressure during inhalation. A machine is used to create this pressure via a hose connecting to a mask worn over a patient’s nose and sometimes mouth. While PAP devices are highly effective when used, they are often noisy and cumbersome, so behavioral interventions may encourage greater use. Service members with PAP devices can still deploy if battery back-up and other resources are available. Other treatment options for OSA, such as a mouthpiece used at night to hold open the airway, nasal devices, and surgery to remove extra tissue in the throat known as uvulopalatopharnygoplasty, are available and work better in mild to moderate cases.
Traditionally, nightmares were indirectly treated by focusing on any underlying condition such as anxiety or PTSD and hoping that the nightmares would resolve as a symptom of that condition. More recent treatments directly address the nightmares, which means mental health providers have greater options if nightmares are the primary complaint or occur residually. Behavioral treatments generally focus on re-scripting, or changing, aspects of the nightmare to allow for either a new alternative dream, a sense of control, and/or exposure. Imagery rehearsal therapy (IRT) limits exposure to the nightmare and requires patients to repeatedly rehearse a new, rescripted version of the nightmare during the day after, with elements of psychoeducation and development of imagery skills in general. A related approach, Exposure, Relaxation, and Rescripting Therapy (ERRT) similarly includes psychoeducation and rehearsal of a rescripted dream, and also incorporates exposure elements (e.g. writing out the original nightmare) and relaxation training. Both approaches have been shown to reduce nightmare frequency to a modest extent and have some preliminary evidence for effectiveness with military members (Escamilla et al., 2012). Pharmacological treatment options largely consist of prazosin, an alpha-blocker originally used for high blood pressure, which has been effective in treating service members and veterans, although some case reports of potential benefits from risperidone and trazodone exist (Escamilla et al.). At this point, no direct comparisons of behavioral treatment and pharmacotherapy specifically for nightmare treatment exist either among civilian or military populations, so we suggest mental health providers consider patient preference and likelihood of follow-up when discussing treatment options.
Specific treatments for circadian rhythm disorders will vary by what subtype is present. Clearly the best first step is to address any environmental or behavioral factors that may be playing a predisposing or precipitating role in the problem (i.e. frequent changes in shift work schedule or inconsistent bed and wake times). One of the authors (WB) has had opportunities to advise commanders on best practices regarding shift work and has been able to develop a schedule that was likely related to a reduction in disciplinary actions associated with falling asleep at the gate (Security Forces) and with medication errors on the night shift (Nursing Staff).
Given that light has the biggest impact on circadian rhythms entrainment for sleep phase disruptions, it should be one of the tools used by providers to advance or delay a sleep phase that is out of sync with environmental (work or social) schedules. In general, light exposure in the evening hours prior to bedtime will delay the sleep schedule with later bed and wake times, and light exposure in the morning several hours prior to preferred wake time or shortly after the wake time required by schedule will advance the sleep schedule.
Other options for circadian rhythms entrainment include melatonin therapy, where melatonin supplementation in the evening hours will advance the sleep schedule and supplementation in the morning hours will delay the sleep schedule. Importantly, because melatonin is considered a dietary supplement and therefore is not federally regulated, actual dosages and components in over-the-counter options may vary. Melatonin and light therapies may be combined; although, whether administered jointly or individually, both should be incorporated with a consistent sleep schedule to maximize benefit.
Lastly, chronotherapy may be used for circadian rhythms entrainment and consists of gradually shifting the sleep schedule from the preferred schedule to the new schedule. Shifting by delaying bedtime often works more smoothly given the relative ease of “staying up” and subsequently building up sleepiness as opposed to forcing sleep onset. However, it may be unrealistic given work schedules for those who already have a delayed sleep phase tendency to allow even several days for alignment with the new schedule.
Sgt. Evertired’s overnight sleep study indicated that he was having 10- 12 hypopnea episodes per hour and in combination with his snoring and daytime sleepiness it suggested he had moderate sleep apnea. During the sleep study he was given a trial of PAP and responded well. He was started on CPAP and has been largely compliant with its use and has experienced a significant reduction in daytime sleepiness, improved sleep quality and mood and a general increase in energy. Upon return to the behavioral provider he continued to complain of some problems with sleep onset and maintenance and occasional nightmares. A course of CBT-I and three sessions devoted to Imagery Rehearsal resulted in significant improvement in sleep quantity and an elimination of nightmares.
Sleep-wake disorders and in particular insomnia, nightmares, OSA and circadian rhythm disorders will continue to be a significant presenting concern of Service members and Veterans. The clinician who is well versed in effective assessment and behavioral treatment techniques will be a valuable asset to these clients. The ability to accurately assess a sleep problem and recognition of conditions that warrant referral to sleep specialists is key to competent care of these patients. Given the effectiveness of treatments for sleep-wake disorders, specifically the key role of behavioral interventions in the treatment of many of these conditions, and because we have the tools to contribute significantly to the care of this clients, behavioral health providers should seek opportunities to gain further competence in assessment and treatment of sleep-wake disorders.
William Brim, PsyD, is the deputy director of the Center for Deployment Psychology (CDP). He joined the Center in 2007. Prior to joining the CDP, Dr. Brim served on active duty as a psychologist in the United States Air Force from 1997 to 2007. The focus of Dr. Brim's clinical work is on the assessment and treatment of posttraumatic stress disorder and insomnia, health psychology clinical practice and supervision and the integration of mental health services in primary care. He has published numerous articles and chapters on military cultural competence and sleep disorders.
Diana C. Dolan, PhD, CBSM is a clinical psychologist serving as an evidence-based psychotherapy trainer with the Center for Deployment Psychology. In this capacity, she develops and presents trainings on a variety of EBPs and deployment-related topics, and provides consultation services. Dr. Dolan is a veteran of the U.S. Air Force. As an active duty psychologist, she served as chief, Primary Care Psychology at Lackland AFB, Texas, overseeing integrated behavioral health services in primary care. She was also responsible for overseeing the base post-deployment health reassessment program. Dr. Dolan has been credentialed by the National Register since 2011.
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