SLEEP DISORDERS AFTER BRAIN INJURY

2 years ago

Sleep problems following traumatic brain injury including concussions are quite common. The fact that multiple levels of the central nervous system are involved in sleep as well as wakefulness, would leave one to conclude that the more extensive the brain damage, the more likely that an individual may suffer from sleep/wake cycle dysfunction problems. These types of problems can lead to additional cognitive and behavioral problems as well as protract the recovery phase after injury.

Types of Sleep Disorders

Of the sleep disorders associated with TBI, the most common involve disordered initiation and/or maintenance of sleep, so-called DIMS. Identification of circadian rhythm/cycle abnormalities may impede rehabilitation efforts and yet, are quite treatable. Circadian rhythm sleep problems are also highly correlated with various psychiatric disorders, particularly seasonal affective disorder, depression and bipolar disorder.

Parasomnias which are undesirable behavioral events, commonly of a motor nature, occur exclusively or predominately during sleep. These conditions include disorders of arousal, REM sleep behavior disorder (RSBD) and nocturnal seizures, among others. They may result in potential injury or disruption to both the patient and/or caregivers. Weight gain associated with TBI (secondary to relative inactivity) and/or due to medication side effects may cause or exacerbate obstructive sleep apnea (OSA). OSA may also be secondary to non-cerebral injuries such as facial fractures with nasal/upper airway involvement and/or more severe whiplash injury and can also be a by-product of weight gain. It is also important to note that OSA is often a pre-existing condition and is frequently undiagnosed prior to the TBI. It is commonly related to anatomical restrictions of upper airway flow, is more common in men and tends to increase in frequency with age. Central apnea (CA) although not particularly common may also be seen in association with TBI. OSA and CA are best differentiated by polysomnography (PSG) (also called a sleep study) which can be done at home or in a hospital-based sleep lab.

Another group of sleep disorders that can be seen following TBI is that of hypersomnia or excessive daytime sleepiness. This condition can also be seen with narcolepsy, even in the absence of sleep deprivation or other identifiable abnormalities such as OSA. Neurogenic fatigue must be differentiated from true idiopathic central nervous system hypersomnia. Certain types of headaches may be associated with specific stages of sleep and thereby lead to sleep disruption. For example, migraine attacks have been described in association with sleep stages 3, 4 and REM (rapid eye movements). Headaches appearing on awakening may be associated with a variety of disorders including obstructive sleep apnea and frontal sinus problems.

There are a number of mental health conditions that can negatively impact sleep quality. The two most common ones, which are also common etiologies of sleep problems in the normal population, include depression and anxiety. Such conditions as post-traumatic stress disorder are also linked with disruptions in sleep. Additionally, one of the most common and under-addressed problems with regard to perpetuating factors for sleep problems is inadequate management of post-traumatic pain disorders. Sleep disorders also put an individual at increased risk for TBI as well as recurrent TBI…just think about the guy with OSA and excessive daytime sleepiness behind the wheel of a car.

Treatment Options

Treatment options for sleep disorders are multiple. The simplest and most basic intervention post TBI sleep problems is providing education regarding “sleep hygiene.” Specifically, that is taking measures that directly reduce or eliminate risk factors that may perpetuate and/or cause sleep problems. One of the most common problems is that of the propensity of individuals who have sleep problems to nap during the day. Ideally, one should try to avoid naps to consolidate better nighttime sleep. As a rule, individuals should only go to bed to sleep when tired. Most importantly, they should wake up at a uniform time on a daily basis. Attempts should be made to avoid caffeine and exercise late in the day as these can interfere with sleep quality. Just as importantly, every effort should be made to avoid alcohol consumption as ingestion of this substance, contrary to popular belief, interferes with sleep. In patients with nocturia (frequent nighttime voiding), every effort should be made to limit fluids later in the day and empty the bladder right before going to bed for the night. Treating associated conditions such as depression, anxiety/PTSD and pain is paramount in optimizing sleep quality. As indicated, medication interventions can be used, although in certain patients such as those with OSA, there may be certain drugs that are contraindicated, as they may exacerbate the sleep disorder in question. There are many sleep medications now available to treat different sleep conditions and part of the challenge is making sure the physician who is treating you understands the correct ones to use as well as medications to avoid if you have a brain injury of any kind.

Other treatments that are more specific for particular sleep disorders can be considered including CPAP (continuous positive airway pressure), intraoral devices, as well as implantable devices like the Inspire unit for OSA; phototherapy, specifically exposure to bright light in the morning; stimulant treatment for hypersomnia and/or narcolepsy with traditional medications and/or newer generation drugs, among other interventions. One needs to be aware that some of the drugs commonly used for sleep initiation and insomnia such as Ambien (zolpidem) may have addictive properties. Trazodone hydrochloride has also been used with good success for sleep initiation, as well as combined sleep initiation and maintenance problems. For problems that are more specific to sleep maintenance, I have generally had better success with noradrenergic agonists such as nortriptyline. It needs to be understood that the dosing of anti-depressant medications when used for sleep problems, generally does not need to be at typical “anti-depressant doses.”

Other Conditions

There are certainly many other conditions that can result in sleep problems that may or may not be related to a history of brain injury including nocturnal bruxisms, restless leg syndrome, periodic leg movements during sleep, and nocturnal myoclonus, among others. Practitioners must keep these more uncommon problems in mind as they may be seen in this patient population but are beyond the scope of a brief review of the topic.

Ideally, it is important to consult with a physician, regardless of specialty, who is familiar with sleep problems in persons with TBI.

Many sleep laboratories focus on sleep disordered breathing and not on other aspects of sleep/wake cycle dysfunction that may be common in this patient population. Therefore, it is important that the referring physician and/or the sleep laboratory physician have an adequate knowledge of the specific problems germane to persons with TBI in order to optimize both assessment and treatment.

Literature

ABOUT THE AUTHOR

Nathan Zasler MD is Founder, CEO & Medical Director of Concussion Care Centre of Virginia, Ltd., as well as Tree of Life Services, Inc. Dr. Zasler is board certified in PM&R, fellowship trained in brain injury and subspecialty certified in Brain Injury Medicine. You can read more about Dr. Zasler HERE.