Table 4.

Twentieth century case studies of presumed CTE with a history of violence or aggressiveness (n = 17) from McKee et al. (20).

Case #	Year*	Age sport began	Years in sport	Initial symptoms and problems	Age of onset of symptoms	Years between retirement and symptoms	Interval between symptom onset and death	Age at death	Cognitive changes	Memory loss	Dementia	Parkinsonism or obvious neurological abnormality***	CTE pathology (88)
8	1967	16	7	Cognitive decline, hemiparesis	25	1	33	58	Yes	Yes	Yes	Yes	N/A
10	1968	15	20	Headaches	36	0	10	46	No	No	No	Yes	N/A
11	1968	19	12	Headaches	31	0	15	46	Yes	Yes	No	Yes	N/A
12	1968	16	16	Slurred speech, gait change	40	8	5	45	Yes	Yes	No	Yes	N/A
15	1973	11	14	Violent outbursts	25	0	38	63	Yes	Yes	No	Yes	Yes CTE
17	1973	16	14	Confusion, falls	30	0	33	63§	Yes	Yes	No	Yes	Yes CTE
19	1973	18	18	Irritability, memory loss, aggression	36	0	25	61	Yes	Yes	No	Yes	No ARTAG
20	1973	13	25	Gait, speech	37	0	46	83	Yes	Yes	No	Yes	Yes CTE
21	1973	16	20	Dysphoria, violence	54	18	8	62	Yes	Yes	Yes	Yes	Yes CTE
22	1973	17	23	Ataxia, falls, weakness	60	20	11	71	Yes	No	No	Yes	Yes CTE
24	1973	NR	NR	Memory loss	40	NR	27	67	Yes	Yes	Yes	NR	Yes CTE/AD
25	1973	NR	NR	Confusion	48	NR	19	67	Yes	Yes	Yes	Yes	No ARTAG
26	1973	14	16	Speech, delirium	43	4	14	57§	Yes	Yes	Yes	Yes	No AD
28**	1973	NR	NR	Aggression	NR	NR	NR	91	No	No	No	No	No Diagnosis
32	1992	NR	>25	NR	NR	NR	NR	63	Yes	Yes		Yes	N/A
34	1996	NR	15	NR	NR	NR	NR	33	Yes	Yes	Yes	NR	N/A
41	1999	NR	10	Cognitive decline, ALS-like syndrome	64	NR	NR	67	Yes	Yes	Yes	Yes	N/A

This information was derived from Table 2 in McKee et al. (20). All cases were reported to have been boxers with the exception of a circus clown who was an achondroplastic dwarf, aged 33 at the time of death, who had 15 years of exposure as a circus clown and participation in dwarf throwing competitions reported by Williams and Tannenberg (89).

^*1967 = Constantinidis and Tissot (90), 1968 = Payne (64), 1973 = Corsellis et al. (4), 1992 = Hof et al. (91), 1996 = Williams and Tannenberg (89), 1999 = No listed authors (92), 2018 = Goldfinger et al. (88);

^**Case 28 said to have boxed professionally in his youth. He was described as being “considered active and mentally alert up to the time of his death” (4); AD, Alzheimer's disease; ARTAG, Aging-related tau astrogliopathy; CTE, chronic traumatic encephalopathy; N/A, not applicable; NR, not reported;

^§Case 17 “Age at Death” reported as 63 years in Corsellis et al. (4) and 62 years in Goldfinger et al. (88); Case 26 “Age at Death” reported as 57 years in Corsellis et al. (4) and 56 years in Goldfinger et al. (88);

^***Obvious neurological abnormality includes two or more of the following: movement abnormalities, decreased facial movement, slowed movements, tremor, rigidity, falls, ocular abnormalities, ptosis, reduced upgaze, gait problems: staggered gait, slowed gait, shuffled gait, ataxia, reduced coordination, speech changes: slowed speech, slurred speech, dysarthria, dysphagia, spasticity.