Who Gets Chronic Traumatic Encephalopathy?

between contact sports participation and chronic traumatic encephalopathy: a
retrospective study.
KF, Blessing MM, Heckman MG, Diehl NN, Serie AM, Paolini MA, Boeve BF, Savica
R, Reichard RR, and Dickson DW. Brain Pathol. 2019. [Epub Ahead of Print].
Full Text Freely Available                                                                        
Home Message
: Among 750 samples of brain tissue
from individuals with and without a history of sport participation, less than 6%
of people showed c
traumatic encephalopathy
(CTE)-related pathology. While most
people don’t develop CTE, roughly 1 in 7 former football players had evidence
of CTE-related pathology compared with ~1 in 18 peers.

Chronic traumatic encephalopathy (CTE) is a
debilitating neurological disorder that has gained a lot of attention because
it is related to repeated brain trauma. Despite the media attention we know
very little about whether the risk of developing CTE is related to
participation in sports at nonelite levels of competition. The researchers of
this study used the Mayo Clinic Tissue Registry to review samples of brain
tissue from 300 former athletes and 450 non-athletes for the presence CTE
pathology or features of CTE. The researchers used obituaries and high school
yearbooks to determine if someone participated in sports (e.g., football,
hockey, soccer). They also used The
Rochester Epidemiology Project, which is a
comprehensive medical records linking system, to identify relevant disorders
(e.g., head trauma, dementia, alcoholism). The researchers identified CTE based
on consensus criteria and features of CTE when a person had multiple lesions
that were possibly CTE, but they failed to fit all of the consensus criteria
(excluding Alzheimer-type pathology and 
aging-related tau pathology). Overall, 66 out of 273 females (24%) and
232 out of 477 males (49%) participated in a contact sport. Forty-two (5.6%)
people had evidence of CTE-related pathology (CTE or features of CTE). Only one
female had any CTE-related pathology. A male with a history of participation in
American football was ~2.6 times more likely to have CTE-related pathology than
a peer (CTE-related pathology: 15% vs 6%; confirmed CTE: 8% vs 3%).  

This study is yet another piece in the
puzzle of understanding how participation in sports may impact the development
of CTE. While more research in this area is needed, the results support prior
findings (see below) that participation in football increases the chances of
CTE development. In fact, more than 1 in 7 former football players in the
cohort had evidence of CTE-related pathology compared with ~1 in 18 peers. A
more detailed analysis with a larger cohort may help us understand who will get
this pathology among people with and without a history of football. This
information will be vital to developing prevention strategies. Some caution
should be taken from this study as the researchers were unable to assess the years
of participation and/or number of head traumas that a person experienced. Despite
this limitation, clinicians can use this study to help educate athletes and
parents regarding CTE and sports participation. Clinicians should highlight
that while football players are more likely to develop CTE, the vast majority
of participants (85%) may not develop CTE and we are trying to figure out why
some people develop CTE. Parents and athletes can then make an informed
decision about the risks and benefits of participating in football.
Questions for Discussion: What questions have you had
from your athletes or parents regarding CTE? How might this study impact your
education of these populations moving forward?
Reviewed by:  Jeffrey Driban