Clinical presentation of chronic traumatic encephalopathy
Abstract
Objective:
The goal of this study was to examine the clinical presentation of chronic traumatic encephalopathy (CTE) in neuropathologically confirmed cases.
Methods:
Thirty-six adult male subjects were selected from all cases of neuropathologically confirmed CTE at the Boston University Center for the Study of Traumatic Encephalopathy brain bank. Subjects were all athletes, had no comorbid neurodegenerative or motor neuron disease, and had next-of-kin informants to provide retrospective reports of the subjects' histories and clinical presentations. These interviews were conducted blind to the subjects' neuropathologic findings.
Results:
A triad of cognitive, behavioral, and mood impairments was common overall, with cognitive deficits reported for almost all subjects. Three subjects were asymptomatic at the time of death. Consistent with earlier case reports of boxers, 2 relatively distinct clinical presentations emerged, with one group whose initial features developed at a younger age and involved behavioral and/or mood disturbance (n = 22), and another group whose initial presentation developed at an older age and involved cognitive impairment (n = 11).
Conclusions:
This suggests there are 2 major clinical presentations of CTE, one a behavior/mood variant and the other a cognitive variant.
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Information & Authors
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© 2013 American Academy of Neurology.
Publication History
Received: March 16, 2013
Accepted: June 18, 2013
Published in print: September 24, 2013
Published online: September 4, 2023
Authors
Author Contributions
Dr. Stern was responsible for drafting the manuscript, study concept and design, and analysis and interpretation of data. He also conducted some of the statistical analyses and had a role in obtaining funding. Mr. Daneshvar participated in drafting the manuscript, as well as acquisition of data, statistical analysis, and interpretation of data. Ms. Baugh participated in drafting the manuscript, as well as study design and acquisition of data. Dr. Seichepine participated in drafting the manuscript, as well as analysis and interpretation of data. Mr. Montenigro participated in drafting the manuscript and in study design. Mr. Riley participated in revising the manuscript, study design, and acquisition of data. Mr. Fritts, Ms. Stamm, Mr. Robbins, and Ms. McHale participated in revising the manuscript and acquisition of data. Ms. Simkin participated in revising the manuscript as well as conducting the APOE genotyping. Dr. Stein and Dr. Alvarez participated in revising the manuscript, as well as acquisition and analysis of neuropathologic data. Dr. Goldstein and Dr. Budson participated in revising the manuscript and interpreting the data. Dr. Kowall participated in revising the manuscript, interpreting the data, and obtaining funding. Mr. Nowinski participated in revising the manuscript, study concept, acquisition of data, and obtaining funding. Dr. Cantu participated in drafting the manuscript, study design and concept, interpreting data, and obtaining funding. Dr. McKee participated in drafting the manuscript, study design and concept, acquiring, analyzing, and interpreting clinical data, acquiring, analyzing, and interpreting the neuropathologic data, and obtaining funding.
Disclosure
R. Stern is funded by NIH grants R01 NS078337, R01 MH080295, R01 CA129769, P30 AG13846, U01 AG10483, and U01 AG015477; and has received research support from the Alzheimer's Association, the Andlinger Foundation, the National Operating Committee on Standards for Athletic Equipment, Janssen Alzheimer's Immunotherapy, Pfizer, and Medivation. He has been a paid consultant to Janssen Alzheimer's Immunotherapy, Outcome Science, and Elan Pharmaceuticals, and he has been a paid Expert Advisor to Eli Lilly. He receives royalties from Psychological Assessment Resources for the publication of neuropsychological tests. D. Daneshvar and C. Baugh report no disclosures. D. Seichepine receives funding from the Center for Integration of Medicine and Innovative Technology, as well as from NIH training grant T32 AG036697. P. Montenigro received support from Boston University School of Medicine for a summer research internship. D. Riley and N. Fritts report no disclosures. J. Stamm is supported by NIH grant F31NS081957. C. Robbins reports no disclosures. L. McHale is paid by Sports Legacy Institute for her work as Director of Family Relations. I. Simkin reports no disclosures. T. Stein is supported by NIH P30 AG13846 pilot grant. V. Alvarez is supported by the Department of Veterans Affairs. L. Goldstein is funded through grants from the NIH P30 AG13846, NASA SK-11-107, DOE DE-PS02-08ER08, and Cure Alzheimer's Fund. A. Budson is funded through the Department of Veterans Affairs. He receives royalties from Elsevier and Wiley-Blackwell for the publication of books. N. Kowall is funded by NIH grant P30 AG13846 and the Department of Veterans Affairs. C. Nowinski is supported by the Center for Integration of Medicine and Innovative Technology and the Andlinger Foundation. He receives consulting fees from MC10, and he receives royalties from the publication of his book, Head Games, and the documentary, "Head Games." R. Cantu is Vice President of the National Operating Committee on Standards for Athletic Equipment, Cofounder and Medical Director of Sports Legacy Institute, and Senior Advisor to the NFL's Head, Neck and Spine Committee. He has received support from the Andlinger Foundation. He gave expert testimony in the trials of Carey vs Northwestern Memorial Hospital, Arbec vs Dr. Hardin and St. Joseph's, and Grane vs Methodist Medical Center of Illinois. He receives royalties from the publication of the books, Catastrophic Football Injuries, Diabetes and Exercise, Neurologic Head and Spine Injuries, and Concussions and Our Kids. A. McKee is funded through NIH grants P30 AG13846, R01 AG1649, and the Department of Veterans Affairs, and received research support for this work from the Department of Veterans Affairs; Veterans Affairs Biorepository (CSP 501); NIA supplement 0572063345-5, National Operating Committee on Standards for Athletic Equipment, the National Football League (unrestricted gift), and the Andlinger Foundation. Go to Neurology.org for full disclosures.
Study Funding
Supported by NIH (R01 NS078337, P30 AG13846), Department of Veterans Affairs (CSP 501, B6796-C), Sports Legacy Institute, National Operating Committee on Standards for Athletic Equipment, and unrestricted gifts from the National Football League and the Andlinger Foundation.
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Stern et al. cited five references, "4, 7-10" three times to advocate that chronic traumatic encephalopathy (CTE) in younger patients presents as a psychiatric disorder versus cognitive impairment in older patients. [1] Reference 10 made no such claim and four of the references [4, 7, 8 and 9] are misrepresented. In Corsellis et al. [reference 4] the presenting symptoms in six of 15 boxers were speech and gait difficulties (estimated onset 39 y/o). Older boxers (n=3) with no CTE symptoms, including cognitive, died at a mean age of 70. We are left with the question: Can alcohol abuse be construed as a "behavior/mood variant" CTE symptom in younger boxers (n=3; mean onset 29 y/o)? Corsellis has been falsely cited as reporting the initial CTE stage is psychiatric. [2] Reference 7 describes one boxer (out of 10) who drank, brawled and was arrested frequently. Oddly, three references, 8-10, were in German and decades old. The review revealed that one patient (out of five) had a psychiatric presentation but an abnormal EEG (reference 8). Another (out of four) was a POW who developed upon his release at age 20 "irritability" and psychosis at age 26. The authors were hesitant to attribute this to boxing (reference 9). The dichotomy of an initial psychiatric presentation in younger patients and cognitive impairment in older patients is not supported by the references cited by Stern et al. Instead, the initial presentation is neither psychiatric nor cognitive, but dysarthria and or parkinsonian symptoms at a young age. [3]
1. Stern RA, Daneshvar DH, Baugh CM, et al. Clinical presentation of chronic traumatic encephalopathy. Neurology 2013; 81:1122-1129.
2. Chin, LS., Gentian T, Cantu, RC. Traumatic encephalopathy related to sports injury. US Neurology 2011; 7: 33-36.
3. Andrikopoulos J. Correspondence regarding chronic traumatic encephalopathy in athletes: progressive tauopathy following repetitive concussion. J Neuropathol Exp Neurol J Neuropathol Exp Neurol. 2014; 73:375; author reply 375.
References 4, 7-10 from Stern et al.:4. Corsellis JA, Bruton CJ, Freeman-Browne D. The aftermath of boxing. Psychol Med 1973;3:270-303.
7. Mawdsley C, Ferguson FR. Neurological disease in boxers. Lancet 1963;2:799-801.
8. Soeder M, Arndt T. Affektive storungen und ver-inderungen des hirnstrombildes bei boxern. Dtsch Med Wochenschr 1954;79:1792-1795.
9. Grahmann H, Ule G. Beitrag zur kenntis der chronischen cerebralen krankheitsbieder bei boxen. Psychiatr Neurol 1957;134:261-283.
10.Jokl E, Guttman E. Munch Med Woch 1931;1:560.
Editors' note: The editors accepted this lengthy response owing to the criticism implied in the original letter.
Robert C. Griggs and Robert Gross
We thank Dr. Andrikopoulos for his comments on the literature. Our study considered the clinical presentation of chronic traumatic encephalopathy (CTE) in neuropathologically confirmed cases of CTE without co-morbid neurological disease. [1] Consistent with earlier reports (references [4, 7-10] in our paper), we identified two clinical presentations in CTE: [1] an initial behavioral/ mood disorder with a younger age of onset and [2] an initial cognitive presentation with an older age of onset. [1] Dr. Andrikopoulos' commentedon our references and not our research findings. Our paper was not a review article. However, we agree that the case literature concerning CTE deserves elaboration.
First, contrary to Dr. Andrikopoulos' interpretation of Ernst Jokl et al. [2] [reference 10 in our paper], we believe that Jokl's clinical observations are complementary to our findings. While originally published in German, Jokl (who established the American College of Sports Medicine) describes his findings in an English editorial for the British Medical Journal, [3] where he clearly identifies a dichotomy: "The point I wish to make is that punch-drunkenness is not a single syndrome. In our first communication on the subject in 1933 the late Eric Guttmann and I made a distinction between two kinds of chronic impairment encountered in boxers-viz., behavior anomalies indicative of psychopathic traits, and neurological psychiatric conditions" (p. 1292) [3].
In 1957, Grahamm and Ule [4] (reference 9 in our paper) provided the 2nd instance of a neuropathologically characterized case of CTE and is consistent with the two initial presentation subtypes. Based on a case series (n=4) and literature review, the authors classify three "chronic cerebral" syndromes in boxers, including: [1] a chronic progressive "dementia" with onset in retirement; [2] a "stationary" syndrome of "neurological defects" with onset "directly related in time to head-blows"; and [3] a predominantly paranoid and psychotic syndrome.
Regarding Corsellis et al. [5] (reference 4 in our paper), Dr. Andrikopoulos states that six of 15 boxers with neuropathologically confirmed CTE had "gait and speech difficulties" as the presenting symptoms rather than behavioral, mood, or cognitive symptoms. We agree with his statement. However, the predominant presenting features in the majority of cases include behavioral, mood, and/or cognitive symptoms. Moreover, we state in our discussion that, "it is noteworthy that motor features, including parkinsonism, were not common in our sample; this is in contrast to some earlier descriptions of CTE in boxers, in which these motor features were quite prominent" (p. 1126). [1] In fact, Corsellis et al. [5] proposed a clinicopathological correlation between "rage reactions" observed in "several" boxers and the tau neurofibrillary tangle pathology localized to the fronto-limbic structures, including the septum. Alternatively, Andrikopoulos questions whether we misconstrued alcohol abuse in three younger boxers as a "behavior/mood variant CTE symptom." This is not the case. Rather, those cases were described as demonstrating "violent outbursts," "rage reactions," "disgusting behavior," and "neglect of appearance," all consistent with our behavioral/mood classification.
Dr. Andrikopoulos also brings attention to a recurring misconception in the literature involving reference 4 in our paper [5], namely the notion of "clinical staging" in CTE. Clinical staging attempts to characterize the progression and pattern of signs and symptoms in a disease. We do not discuss clinical staging, but rather describe two distinct clinical presentations and progressions in neuropathologically confirmed CTE cases. That clinical staging is often misattributed to Corsellis is, however, correct. It was actually GW Roberts who described three CTE stages in his archival re-analysis of the 15 cases originally described by Corsellis et al. (1973) [6,7]. Roberts cites Guterman and Smith [8] as evidence that the clinical symptoms are "well documented" as having "insidious onset, behavioral disturbances, [and] progressive dementia." (p. 377) Dr. Andrikopoulos suggests that "one patient (out of five) had a psychiatric presentation" in the study by Soeder et al. [9], reference 8 in our paper; this suggestion is incorrect from our point of view. In that study, the authors perform neurological and "psychopathological" examinations and collect EEG and neuroimaging studies (pneumoencephalography) in five young cases (mean age at exam 32.8) who report extensive exposure to boxing. All five cases had prominent behavioral and/or mood symptoms (e.g., euphoria, depression, explosive rage), and two of the behavioral/mood predominant cases had little to no cognitive or motor symptoms, despite markedly pathological EEG findings [9].
In the study by Mawdsley et al. [10], reference 7 in our paper, there were two cases with cognitive symptoms at disease onset (cases 3 and 10, mean age at onset 42.5). Case 3 represents a clear example of a cognitive predominant presentation with "deterioration in his memory" beginning at "the age of 50," with "speech and gait normal" on examination. In contrast, three cases (cases 1, 4, 8) had predominantly behavioral/mood symptoms at onset in their mid to late thirties.
We maintain that the two clinical presentations of CTE reported in our paper [1] are consistent with earlier case reports in boxers [references 4,7-10 in our paper]. Jokl and Guttman [2] and Grahmann and Ule [4] not only observed differences between cases, but classified them into a "paranoid-psychopathic" group or a "progressive dementia" group. Although we can, indeed, learn from and argue over the earlier case reports of boxers over the past 80 years, we now must move beyond case reports to study more in depth the clinical presentation of CTE and other long-term consequences of repetitive brain trauma. This field remains in its infancy, in contrast to what might be believed through much of the media hype over the past several years. There is a need for biomarker development for in vivo diagnosis of CTE and for longitudinal studies, with large samples, to characterize the clinical presentation and course of this disease.
1. Stern RE, Daneshvar DH, Baugh CM, et al. Clinical presentation of chronic traumatic encephalopathy. Neurology 2013; 81:1122-1129.
2. Jokl E, Guttman E. Neurologisch-Psychiatrische Untersuchung an Boxern. Munch Med Woch 1933;1:560-562.
3.Jokl E. Punch-drunkenness, Notes and Comments. Br Med J 1950;2:1292.
4. Grahmann H, Ule G. Beitrag zur Kenntis der chronischen cerebralen Krankheitsbilder bei Boxern (Dementia pugilistica und traumatische Boxer-Encephalopathie). Psychiatr Neurol (Basel) 1957;134:261-283.
5. Corsellis JA, Bruton CJ, Freeman-Browne D. The aftermath of boxing. Psychol Med 1973;3:270-303.
6. Roberts, GW, Allsop D, Bruton C. The occult aftermath of boxing. J Neurol Neurosurg Psychiat 1990,53:373-378.
7. Roberts GW. Immunocytochemistry of neurofibrillary tangles in dementia pugilistica and Alzheimer's disease: evidence for common genesis. Lancet 1988;332:1456-1458.
8. Guterman A, Smith RW. Neurological sequelae of boxing. Sports Med 1987;4:194-210.
9. Soeder M, Arndt T. Affektive Storungen und Veranderungen des Hirnstrombildes bei Boxern. Dtsch Med Wochenschr 1954;79:1792-1795.
10. Mawdsley C, Ferguson FR. Neurological disease in boxers. Lancet 1963;2:799-801.
For disclosures, please contact the editorial office at [email protected].