Traumatic brain injury: Epidemiology, classification, and pathophysiology
- J Claude Hemphill, III, MD, MAS
J Claude Hemphill, III, MD, MAS
- Professor of Neurology
- University of California, San Francisco
Traumatic brain injury (TBI) is the leading cause of death in North America for individuals between the ages of 1 and 45. Many survivors live with significant disabilities, resulting in major socioeconomic burden as well. In 2000, the economic impact of TBI in the United States was estimated to be $9.2 billion in lifetime medical costs and $51.2 billion in productivity losses .
The focus of this topic is on the epidemiology, pathophysiology and classification of TBI. Other aspects of traumatic head injury are discussed separately. (See "Management of acute severe traumatic brain injury" and "Concussion and mild traumatic brain injury" and "Intracranial epidural hematoma in adults" and "Post-traumatic seizures and epilepsy" and "Subdural hematoma in adults: Etiology, clinical features, and diagnosis" and "Skull fractures in adults".)
The overall incidence of TBI in the United States was estimated to be 538.2 per 100,000 population, or around 1.5 million new cases in 2003 . Somewhat lower rates are reported in Europe (235 per 100,000) and Australia (322 per 100,000) [2,3].
Rates of TBI are highest in the very young (age group zero to four years) and in adolescents and young adults (15 to 24 years); there is another peak in incidence in the elderly (age >65 years) . Approximately 78 percent of TBI are treated in the emergency department only; 19 percent of patients require hospitalization, and 3 percent are fatal. Most cases treated in emergency departments occur in the very young (ages zero to four years), while hospitalization rates are highest in patients older than 65 years.
As with most traumatic injuries, the incidence of TBI is significantly higher in men compared to women, with ratios that vary between 2.0 to 1 and 2.8 to 1 [4-7]. For severe TBI, the gender ratio is more pronounced, 3.5 to 1. Lower socioeconomic status, alcohol and drug use, and underlying psychiatric and cognitive disorders are also risk factors for head injury [7,8].
Subscribers log in hereLiterature review current through: Aug 2017. | This topic last updated: Nov 08, 2016.References
- Rutland-Brown W, Langlois JA, Thomas KE, Xi YL. Incidence of traumatic brain injury in the United States, 2003. J Head Trauma Rehabil 2006; 21:544.
- Tagliaferri F, Compagnone C, Korsic M, et al. A systematic review of brain injury epidemiology in Europe. Acta Neurochir (Wien) 2006; 148:255.
- Hillier SL, Hiller JE, Metzer J. Epidemiology of traumatic brain injury in South Australia. Brain Inj 1997; 11:649.
- Langlois JA, Keyl PM, Guralnik JM, et al. Characteristics of older pedestrians who have difficulty crossing the street. Am J Public Health 1997; 87:393.
- Kraus JF, McArthur DL. Epidemiologic aspects of brain injury. Neurol Clin 1996; 14:435.
- Feigin VL, Theadom A, Barker-Collo S, et al. Incidence of traumatic brain injury in New Zealand: a population-based study. Lancet Neurol 2013; 12:53.
- Ilie G, Boak A, Adlaf EM, et al. Prevalence and correlates of traumatic brain injuries among adolescents. JAMA 2013; 309:2550.
- Liao CC, Chiu WT, Yeh CC, et al. Risk and outcomes for traumatic brain injury in patients with mental disorders. J Neurol Neurosurg Psychiatry 2012; 83:1186.
- Langlois JA, Rutland-Brown W, Thomas KE. Traumatic brain injury in the United States: emergency department visits, hospitalizations, and deaths. Centers for Disease Control and Prevention, Atlanta, 2006.
- Jennett B, Frankovyski RF. The epidemiology of head injury. In: Handbook of Clinical Neurology, Braakman R (Ed), Elsevier, New York 1990. Vol 13, p.1.
- Butcher I, McHugh GS, Lu J, et al. Prognostic value of cause of injury in traumatic brain injury: results from the IMPACT study. J Neurotrauma 2007; 24:281.
- Summers CR, Ivins B, Schwab KA. Traumatic brain injury in the United States: an epidemiologic overview. Mt Sinai J Med 2009; 76:105.
- Thurman DJ, Alverson C, Dunn KA, et al. Traumatic brain injury in the United States: A public health perspective. J Head Trauma Rehabil 1999; 14:602.
- Zaloshnja E, Miller T, Langlois JA, Selassie AW. Prevalence of long-term disability from traumatic brain injury in the civilian population of the United States, 2005. J Head Trauma Rehabil 2008; 23:394.
- Steyerberg EW, Mushkudiani N, Perel P, et al. Predicting outcome after traumatic brain injury: development and international validation of prognostic scores based on admission characteristics. PLoS Med 2008; 5:e165; discussion e165.
- Menon D, Harrison D. Prognostic modelling in traumatic brain injury. BMJ 2008; 336:397.
- MRC CRASH Trial Collaborators, Perel P, Arango M, et al. Predicting outcome after traumatic brain injury: practical prognostic models based on large cohort of international patients. BMJ 2008; 336:425.
- Saatman KE, Duhaime AC, Bullock R, et al. Classification of traumatic brain injury for targeted therapies. J Neurotrauma 2008; 25:719.
- Teasdale G, Jennett B. Assessment of coma and impaired consciousness. A practical scale. Lancet 1974; 2:81.
- Balestreri M, Czosnyka M, Chatfield DA, et al. Predictive value of Glasgow Coma Scale after brain trauma: change in trend over the past ten years. J Neurol Neurosurg Psychiatry 2004; 75:161.
- Stocchetti N, Pagan F, Calappi E, et al. Inaccurate early assessment of neurological severity in head injury. J Neurotrauma 2004; 21:1131.
- Stead LG, Wijdicks EF, Bhagra A, et al. Validation of a new coma scale, the FOUR score, in the emergency department. Neurocrit Care 2009; 10:50.
- Wijdicks EF, Bamlet WR, Maramattom BV, et al. Validation of a new coma scale: The FOUR score. Ann Neurol 2005; 58:585.
- Eken C, Kartal M, Bacanli A, Eray O. Comparison of the Full Outline of Unresponsiveness Score Coma Scale and the Glasgow Coma Scale in an emergency setting population. Eur J Emerg Med 2009; 16:29.
- Marshall LF, Marshall SB, Klauber MR, et al. The diagnosis of head injury requires a classification based on computed axial tomography. J Neurotrauma 1992; 9 Suppl 1:S287.
- Maas AI, Hukkelhoven CW, Marshall LF, Steyerberg EW. Prediction of outcome in traumatic brain injury with computed tomographic characteristics: a comparison between the computed tomographic classification and combinations of computed tomographic predictors. Neurosurgery 2005; 57:1173.
- Maas AI, Stocchetti N, Bullock R. Moderate and severe traumatic brain injury in adults. Lancet Neurol 2008; 7:728.
- Moen KG, Skandsen T, Folvik M, et al. A longitudinal MRI study of traumatic axonal injury in patients with moderate and severe traumatic brain injury. J Neurol Neurosurg Psychiatry 2012; 83:1193.
- Harhangi BS, Kompanje EJ, Leebeek FW, Maas AI. Coagulation disorders after traumatic brain injury. Acta Neurochir (Wien) 2008; 150:165.
- Allard CB, Scarpelini S, Rhind SG, et al. Abnormal coagulation tests are associated with progression of traumatic intracranial hemorrhage. J Trauma 2009; 67:959.
- Wafaisade A, Lefering R, Tjardes T, et al. Acute coagulopathy in isolated blunt traumatic brain injury. Neurocrit Care 2010; 12:211.
- Stein SC, Young GS, Talucci RC, et al. Delayed brain injury after head trauma: significance of coagulopathy. Neurosurgery 1992; 30:160.
- Murray GD, Butcher I, McHugh GS, et al. Multivariable prognostic analysis in traumatic brain injury: results from the IMPACT study. J Neurotrauma 2007; 24:329.
- Zehtabchi S, Soghoian S, Liu Y, et al. The association of coagulopathy and traumatic brain injury in patients with isolated head injury. Resuscitation 2008; 76:52.
- Büki A, Koizumi H, Povlishock JT. Moderate posttraumatic hypothermia decreases early calpain-mediated proteolysis and concomitant cytoskeletal compromise in traumatic axonal injury. Exp Neurol 1999; 159:319.
- Coles JP, Minhas PS, Fryer TD, et al. Effect of hyperventilation on cerebral blood flow in traumatic head injury: clinical relevance and monitoring correlates. Crit Care Med 2002; 30:1950.
- Diringer MN, Videen TO, Yundt K, et al. Regional cerebrovascular and metabolic effects of hyperventilation after severe traumatic brain injury. J Neurosurg 2002; 96:103.
- Kroemer G, Galluzzi L, Brenner C. Mitochondrial membrane permeabilization in cell death. Physiol Rev 2007; 87:99.
- Morganti-Kossmann MC, Rancan M, Stahel PF, Kossmann T. Inflammatory response in acute traumatic brain injury: a double-edged sword. Curr Opin Crit Care 2002; 8:101.
- Oertel M, Boscardin WJ, Obrist WD, et al. Posttraumatic vasospasm: the epidemiology, severity, and time course of an underestimated phenomenon: a prospective study performed in 299 patients. J Neurosurg 2005; 103:812.
- Vespa P, Bergsneider M, Hattori N, et al. Metabolic crisis without brain ischemia is common after traumatic brain injury: a combined microdialysis and positron emission tomography study. J Cereb Blood Flow Metab 2005; 25:763.
- Yi JH, Hazell AS. Excitotoxic mechanisms and the role of astrocytic glutamate transporters in traumatic brain injury. Neurochem Int 2006; 48:394.
- Stein SC, Chen XH, Sinson GP, Smith DH. Intravascular coagulation: a major secondary insult in nonfatal traumatic brain injury. J Neurosurg 2002; 97:1373.