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The Chronic Effects of Neurotrauma Consortium or CENC is a federally funded research project devised to address the long-term effects of mild traumatic brain injury in military service personnel (SMs) and Veterans. Announced by President Barack Obama on August 20, 2013, the CENC was one of two major initiatives developed in response to the injuries incurred by U.S. service personnel during Operation Enduring Freedom and Operation Iraqi Freedom.〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕 The project is jointly funded in the amount of $62.175 million by the Department of Defense (DoD) and the Department of Veterans Affairs (VA). The CENC is led by Dr. David X. Cifu of the Virginia Commonwealth University.〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕 ==Background== Nearly 20% of the more than 2.5 million U.S. Service Members (SMs) deployed since 2003 to Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) have sustained at least one traumatic brain injury (TBI), predominantly mild TBI (mTBI),〔Warden D. Military TBI during the Iraq and Afghanistan wars. J Head Trauma Rehabil. 2006; 21 (5): 398-402.〕〔(【引用サイトリンク】 publisher=() )〕 and almost 8% of all OEF/OIF Veterans demonstrate persistent post-TBI symptoms more than six months post-injury.〔Scholten JD, Sayer NA, Vanderploeg RD, Bidelspach DE, Cifu DX: Analysis of US Veterans Health Administration comprehensive evaluations for traumatic brain injury in Operation Enduring Freedom and Operation Iraqi Freedom Veterans. Brain Injury 2012;26(10):1177-1184.〕〔Taylor BC, Hagel EM, Carlson KF, Cifu DX, Cutting A, Bidelspach DE, Sayer NA: Prevalence and costs of co-occurring traumatic brain injury with and without psychiatric disturbance and pain among Afghanistan and Iraq war Veteran VA users. Med Care 2012;50(4):342-6.〕 Explosive munitions, predominantly improvised explosive device’ (IEDs), have caused the overwhelming majority of these identified cases. The incidence is likely even significantly higher than reported, as many mTBIs may go unrecognized during and even after deployment because of more visible concomitant injuries capturing greater attention, clinicians’ limited awareness of the often subtle initial findings, and patients’ reduced subjective awareness related to cognitive deficits in the acute period.〔Jordan BD: Chronic Traumatic Brain Injury Associated with Boxing. Semin Neurol 2000; 20(2): 179-186.〕 Acute mTBI effects are typically transient, with headache, cognitive, behavioral, balance, and sleep symptoms most often seen in the first one to three months post-injury. However, in a small percentage of individuals, these difficulties persist and even lead to lifelong disability. In these individuals, additional chronic effects, including neuroendocrinologic abnormalities, seizures and seizure-like disorders, fatigue, vision and hearing abnormalities, and numerous other somatic symptoms are more common over time. The long-term effects from these single or repeated TBIs on the persistence of these symptoms, on combat and trauma-related comorbidities, and on long-term brain functioning are unknown. Increasing evidence supports the linkage between both concussions and combat-related trauma with a degenerative neurologic disorder known as chronic traumatic encephalopathy (CTE), which results in progressive cognitive and behavioral decline in sub-populations that are 5 to 50 years out from repeated or cumulative exposures.〔Gavett B, Stern R, McKee A. Chronic traumatic encephalopathy: A potential late effect of sport-related concussive and subconcussive head trauma. Clin Sports Medicine 2011;30(1): 179-88.〕〔Guskiewicz KM, Marshall SW, Bailes J, et al. Association between recurrent concussion and late-life cognitive impairment in retired professional football players. Neurosurger 2005; 57 (4): 719-26.〕〔Omalu BI, DeKosky ST, Minster RL, Kamboh MI, Hamilton RL, Wecht CH: Chronic traumatic encephalopathy in a National Football League player. Neurosurg 2005 Jul;57(1):128-34; discussion 12834.〕 The possibility of a link between mTBI, persistent symptoms, and early dementia has widespread implications for SMs and Veterans; however, these chronic and late-life effects of mTBI are poorly understood. TBIs of mixed severity have been statistically linked to a higher incidence of Alzheimer's disease (AD) and other dementias and a reduced-age of onset of AD, although negative findings have also been reported.〔Plassman BL, Havlik RJ, Steffens DC, et al. Documented head injury in early adulthood and risk of Alzheimer's disease and other dementias. Neurology. 2000; 55(8): 1158-1166.〕〔Mortimer JA, French LR, Hutton JT, Schuman LM. Head injury as a risk factor for Alzheimer's disease. Neurology. 1985; 35:264–267.〕〔Nemetz PN, Leibson C, Naessens JM, et al. Traumatic brain injury and time to onset of Alzheimer's disease: A population based study. Am J Epidemiol. 1999; 149 (1): 32-40.〕〔Williams DB, Annegers JF, Kokmen E, O'Brien PC, Kurland LT: Brain injury and neurologic sequelae: A cohort study of dementia, parkinsonism, and amyotrophic lateral sclerosis. Neurol 1991; 41(10): 155463.〕〔McKee AC, Cantu RC, Nowinski CJ, Hedley-Whyte ET, Gavett BE, Budson AE, Santini VE, Lee H, Kubilus CA, Stern RA: Chronic Traumatic Encephalopathy in Athletes: Progressive Tauopathy following Repetitive Head Injury. Neuropathol Exp Neurol. 2009 July; 68(7): 709–735.〕 Although it has long been suspected that repeated concussions can contribute to the development of dementia-like symptoms many years after the injuries, CTE has been almost exclusively studied in boxing. CTE has been reported to occur in retired boxers at higher rates and younger ages compared with dementia in the general population.〔Corsellis J.A.N., Bruton CJ, Freeman-Browne D: The aftermath of boxing. Psychological Medicine / Volume 3 / Issue 03 / August 1973, pp 270-303.〕〔Roberts AH. Brain damage in boxers: A study of the prevalence of traumatic encephalopathy among exprofessional boxers. London: Pitman Medical & Scientific Publishing Co, Ltd; 1969.〕〔Plassman BL, Havlik RJ, Steffens DC, et al. Documented head injury in early adulthood and risk of Alzheimer's disease and other dementias. Neurology. 2000; 55(8): 1158-1166.〕 More recently, however, brain autopsies of athletes from a variety of sports (boxing, football, hockey) with confirmed CTE have demonstrated elevated tau proteins, tau-immunoreactive neurofibrillary tangles, and neuropil threads, suggesting that pathological processes similar to those occurring in AD may be involved. The brain structures damaged in CTE are critical for memory and executive function.〔Warden D. Military TBI during the Iraq and Afghanistan wars. J Head Trauma Rehabil. 2006; 21 (5): 398-402.〕〔Meyer K, Marion D, Coronel H, Jaffee M. Combat-related traumatic brain injury and its implications to military healthcare. Psychiatric Clinics of N Americ. 2010; 33(4), 783-796.〕 One cross-sectional study of clinically documented civilian TBI of mixed severity in late-life found impairment compared to controls in many tests, including episodic memory, short-term memory, visuospatial processing, object naming, and semantic processing .〔Butler RJ: Neuropsychological investigation of amateur boxers. Br J Sports Med1994;28:187-190.〕 In CTE, neuropsychological deficits have been noted, but appropriate norms do not exist.〔Petersen RC: Mild cognitive impairment as a diagnostic entity. Journal of Internal Medicine 2004;256 (3):183–194.〕 A meta-analysis found no cognitive effects in 289 amateur boxers;〔Bäckman, Lars; Jones, Sari; Berger, Anna-Karin; Laukka, Erika Jonsson; Small, Brent J.: Cognitive impairment in preclinical Alzheimer's disease: A meta-analysis. Neuropsychol 2005;19(4): 520-531〕 however, a more recent large survey study suggested that multiple concussions may increase the risk of late-life cognitive dysfunction.〔Gavett B, Stern R, McKee A. Chronic traumatic encephalopathy: A potential late effect of sport-related concussive and subconcussive head trauma. Clin Sports Medicine 2011;30(1): 179-88.〕 Specifically, a mild cognitive impairment (MCI) diagnosis and self-reported memory problems were more common among football players who reported three or more concussions than among those who reported none.〔Gavett B, Stern R, McKee A. Chronic traumatic encephalopathy: A potential late effect of sport-related concussive and subconcussive head trauma. Clin Sports Medicine 2011;30(1): 179-88.〕 Basic science modeling for blast and repetitive injury, chronic sequelae, and neurodegeneration are limited. Additionally, longitudinal research bridging SMs and Veterans with neurotrauma is fragmented and incompletely linked with the strategic needs and vision of the Departments of Defense (DoD) and Veterans Affairs (VA). In short, critical gaps exist in the literature, with a paucity of prospective, controlled studies on late-life outcomes and neurodegeneration after mTBI and related basic science research. These research gaps are particularly prominent in the injuries and difficulties seen in combat-exposed populations. The existing research, although suggestive, is not rigorous or robust enough to allow for a clear understanding of the relationships, risks, and potential effective interventions for mTBI, chronic symptoms, and neurodegeneration. To date, no controlled prospective longitudinal study has examined the late-life cognitive, behavioral, systemic, and functional effects of TBI of any severity. Given the absence of prospective studies, the association between TBI and early neurodegeneration is merely theoretical, and the actual risk factors and rate/extent of physiologic and clinical decline over time are unknown. It is also unclear whether a single TBI may be enough to begin a degenerative cascade in select individuals or whether a critical number (dose threshold) of TBIs is needed to “prime” the central nervous system for degeneration. As the majority of TBIs in the military are mild, prospective studies of cognitive outcomes from mild injury are necessary to determine the long-term risks posed to SMs and Veterans. The potential link between mTBI and the development of early dementia is a significant concern for not only at-risk SMs, Veterans, and their families, but also for DoD and VA resource planning, given the high service utilization in the DoD and VA health systems associated with dementia.〔Taber KH, Warden DL, Hurley RA: Blast-Related Traumatic Brain Injury: What Is Known? J Neuropsychiatr Clin Neurosci 2006;18:141-145〕 Given these gaps in scientific research and knowledge, the military- and Veteran-specific issues involved, and the importance of a uniform approach to this critical set of problems, the Department of Defense and the Department of Veterans Affairs jointly issued a request for proposals to fund a 5-year, $62.175 million project to address these concerns. After a competitive application process, a consortium led by Virginia Commonwealth University prevailed and was announced as the recipient of the award by President Obama on August 20, 2013.〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕〔(【引用サイトリンク】 publisher=() )〕 At the time of the award, this was the single largest grant ever awarded to Virginia Commonwealth University.〔(【引用サイトリンク】 publisher=() )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Chronic Effects of Neurotrauma Consortium」の詳細全文を読む スポンサード リンク
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