Traumatic brain injury (TBI) is best defined as an alteration in brain functioning or brain pathology caused by an external force. The rapid acceleration or deceleration external forces can be caused by blunt trauma, penetrating objects, or blast waves. The resulting primary damage includes shearing/tearing injuries of white matter, focal contusions, hematomas, or cerebral edema. Soon after the primary damage, a cascade of metabolic events sets in, which can cause secondary brain damage that may result from the generation of free radicals, release of neurotransmitters, inflammatory responses, calcium-mediated damage, mitochondrial dysfunction, and gene activation. TBI is associated with both focal and diffuse neuronal damage at the site of impact and in more distant brain regions.
TBI is classified as mild, moderate, or severe using the Glasgow Coma Scale (mild, 13 to 15; moderate, 9 to 12; severe, 8 or less); by the duration of loss of consciousness (mild, 30 minutes or less; moderate, 30 minutes to 24 hours; severe, more than 24 hours); or by the duration of posttraumatic amnesia (mild, 1 hour or less; moderate, 1 to 24 hours; severe, 1 to 7 days; and very severe, more than 1 week).
Sleep-related problems are among the most disabling consequences of TBI, with multiple influences: impairment of neuronal plasticity, metabolomic alterations, loss of vascular homeostasis, and disruption of the blood-brain barrier. Moreover, patients with TBI sleep disturbances are more sensitive to pain; are at greater risk for neuropsychiatric problems, such as depression and anxiety; perform poorly on neuropsychological tests of memory, attention, and executive function; and have worse social functioning.1 They have longer hospitalization stays and once discharged from the hospital are at increased risk for suicide.2,3
Sleep disturbances can occur during both the acute and chronic phases of injury. Acute posttrauma phase sleep problems have the potential to interfere with neuronal recovery that may be complicated further by treatment with medications, such as benzodiazepines and haloperidol, which can be detrimental to the recovering nervous system. In the subacute and chronic phases, daytime drowsiness can impair participation in rehabilitation while nighttime wakefulness is often associated with psychiatric problems, behavioral dyscontrol syndromes, and overall poorer quality of life.
Patients with all severities of TBI are at risk for sleep problems, although some studies have noted increased rates with mild compared with severe TBI.4-6 However, these findings may be due to a lack of awareness or underreporting in persons with severe TBI, or perhaps because of the increased sensitivity to changes after mild TBI. Some findings suggest that there are changes in polysomnographic measures following TBI, such as longer sleep onset latencies, shorter REM onset latencies, frequent nighttime awakenings, and higher proportion of stage 1 sleep.7-10
The sleep-wake cycle depends on the coordinated function of multiple brain regions, including the brain stem, basal forebrain, hypothalamus, and the frontal-subcortical system, as well as a balance between the arousal activating and inhibitory systems (Figure). CT and other structural imaging devices can miss sleep-associated microstructural abnormalities in the brain. For example, in one study, CT scans did not pick up any brain damage, but when polysomnography was done, significant differences in electroencephalogram power spectra data were seen.11
The causes of sleep disturbances after TBI are not well understood. However, the mechanisms underlying sleep-wake cycle problems may include the disruption of neural circuits as well as a myriad of other medical and psychiatric disturbances and environmental factors.
Dr Rao is Medical Director of the Brain Injury Clinic, Community Psychiatry Program at the Johns Hopkins Bayview Medical Center and Director of the Behavioral Neurology and Neuropsychiatry Fellowship Program in the department of psychiatry at The Johns Hopkins University School of Medicine in Baltimore. Dr Neubauer is Associate Director of The Johns Hopkins Sleep Disorders Center and Associate Professor of Psychiatry and Behavioral Sciences at The Johns Hopkins University School of Medicine. Dr Vaishnavi is Director of the Neuropsychiatric Clinic at Carolina Partners, he is staff neuropsychiatrist at the Preston Robert Tisch Brain Tumor Center of the Duke University Medical Center, Clinical Associate in the department of psychiatry and behavioral sciences, and Consulting Associate in the department of community and family medicine at Duke University Medical Center, Durham, NC. The authors report no conflicts of interest concerning the subject matter of this article.
1. Lucke-Wold BP, Smith KE, Nguyen L, et al. Sleep disruption and the sequelae associated with traumatic brain injury. Neurosci Biobehav Rev. 2015; 55:68-77.
2. Makley MJ, English JB, Drubach DA, et al. Prevalence of sleep disturbance in closed head injury patients in a rehabilitation unit. Neurorehabil Neural Repair. 2008;22:341-347.
3. Pigeon WR, Pinquart M, Conner K. Meta-analysis of sleep disturbance and suicidal thoughts and behaviors. J Clin Psychiatry. 2012;73:e1160-e1167.
4. Beetar JT, Guilmette TJ, Sparadeo FR. Sleep and pain complaints in symptomatic traumatic brain injury and neurologic populations. Arch Phys Med Rehabil. 1996;77:1298-1302.
5. Clinchot DM, Bogner J, Mysiw WJ, et al. Defining sleep disturbance after brain injury. Am J Phys Med Rehabil. 1998;77:291-295.
6. Ouellet MC, Beaulieu-Bonneau S, Morin CM. Insomnia in patients with traumatic brain injury: frequency, characteristics, and risk factors. J Head Trauma Rehabil. 2006;21:199-212.
7. Baumann CR, Werth E, Stocker R, et al. Sleep-wake disturbances 6 months after traumatic brain injury: a prospective study. Brain. 2007;130(pt 7):1873-1883.
8. Parcell DL, Ponsford JL, Redman JR, Rajaratnam SM. Poor sleep quality and changes in objectively recorded sleep after traumatic brain injury: a preliminary study. Arch Phys Med Rehabil. 2008;89: 843-850.
9. Schreiber S, Barkai G, Gur-Hartman T, et al. Long-lasting sleep patterns of adult patients with minor traumatic brain injury (mTBI) and non-mTBI subjects. Sleep Med. 2008;9:481-487.
10. Ouellet MC, Morin CM. Subjective and objective measures of insomnia in the context of traumatic brain injury: a preliminary study. Sleep Med. 2006; 7:486-497.
11. Rao V, Bertrand M, Rosenberg P, et al. Predictors of new-onset depression after mild traumatic brain injury. J Neuropsychiatry Clin Neurosci. 2010;22: 100-104.
12. Mazwi NL, Fusco H, Zafonte R. Sleep in traumatic brain injury. Handb Clin Neurol. 2015;128: 553-566.
13. Castriotta RJ, Murthy JN. Sleep disorders in patients with traumatic brain injury: a review. CNS Drugs. 2011;25:175-185.
14. Webster JB, Bell KR, Hussey JD, et al. Sleep apnea in adults with traumatic brain injury: a preliminary investigation. Arch Phys Med Rehabil. 2001;82:316-321.
15. Masel BE, Scheibel RS, Kimbark T, Kuna ST. Excessive daytime sleepiness in adults with brain injuries. Arch Phys Med Rehabil. 2001;82:1526-1532.
16. Verma A, Anand V, Verma NP. Sleep disorders in chronic traumatic brain injury. J Clin Sleep Med. 2007;3:357-362.
17. Bjorvatn B, Grønli J, Pallesen S. Prevalence of different parasomnias in the general population. Sleep Med. 2010;11:1031-1034.
18. McHugh PR, Slavney PR. The Perspectives of Psychiatry. 2nd ed. Baltimore: Johns Hopkins University Press; 1998.
19. Viola-Saltzman M, Watson NF. Traumatic brain injury and sleep disorders. Neurol Clin. 2012;30: 1299-1312.
20. Defense Centers of Excellence for Psychological Health and Traumatic Brain Injury. Defense and Veterans Brain Injury Center. Management of Sleep Disturbances Following Concussion/mTBI: Guidance for the Primary Care Manager in Deployed and Non-Deployed Settings. June 2014. https://dvbic.dcoe.mil/sites/default/files/2014_Sleep_CST_07.30.14.pdf. Accessed July 22, 2015.
21. Fichtenberg NL, Millis SR, Mann NR, et al. Factors associated with insomnia among post-acute traumatic brain injury survivors. Brain Inj. 2000;14:659-667.
22. Shekleton JA, Parcell DL, Redman JR, et al. Sleep disturbance and melatonin levels following traumatic brain injury. Neurology. 2010;74:1732-1738.
23. Drake ME Jr. Jactatio nocturna after head injury. Neurology. 1986;36:867-868.