Apr 6, 2018
Show Notes for Podcast Seven of seX & whY, Part
1
Thank you for Alyson McGregor for correctly pointing out
that although the NIH, as of January 2016, does require its basic
scientists to include both males and female animals in their grant
proposals it is not called the “Research for All Act”. The Research
for All Act of 2014 is actually a bill sponsored by Congressman Jim
Cooper of Tennessee that would require, among other things, that
the FDA have access to subgroup analysis of data by sex prior to
granting expedited approval of a new product. As of now, this bill
has not passed.
Host: Jeannette Wolfe
Guests:
Dr. Neha Raukar, Emergency and Sports Medicine Physician
Katherine Snedaker, Executive Director of Pink Concussions
Topic: Sex and Gender Differences in
Concussions
Take home points
- The research behind traumatic brain injury is rapidly evolving
as technology advances are allowing us to better understand how the
human brain works and the nuances between male and female
brains
- We still have a long way to go because most of the basic
science surrounding traumatic brain injury has been conducted on
male animals
- In 2015 the NIH passed The Research for All Act that requires
NIH funded basic science to include both male and female animals or
be able to justify their exclusion
- Men, compared to women, have an overall greater incidence of
traumatic brain injury and this is likely associated with
differences in risk tolerance and exposure to activities associated
with potential injury
- In situations in which risk exposure is the same- like playing
basketball or soccer- after sustaining the same impact, women
appear to have a lower neurobiological threshold to obtain a
traumatic brain injury than men
- Definitive/proportionate reasons for these differences are not
fully understood, however possible factors include:
- Weaker neck muscles
- Decreased neurobiological threshold for injury
- Hormonal differences
- Reporting bias- this theory is quite controversial and it was
emphasized throughout the podcast that many athletes, especially at
elite levels- will underreport symptoms regardless of their
biological sex
- Hormonal influences- it appears that a woman’s vulnerability to
traumatic brain injury may vary depending upon where she is within
her menstrual cycle (with injury during the luteal phase leading to
increased concussive symptoms) or whether or not she is on oral
contraceptives (with some evidence that women on OCPs having
decreased symptoms).
- Symptoms of concussion can be broken down into different
categories:
- Cognitive- issues with memory/concentration/fogginess
- Emotional- anxiety, irritability/sadness
- Somatic- headaches/ light noise sensitivity/nausea and
vomiting
- Vesitibular/Ocular- balance, eye tracking
- Sleep
References:
http://www.pinkconcussions.com/science/concussion-info/
Collins, C.L., Fletcher, E.N., Fields, S.K. et al. Neck
Strength: A Protective Factor Reducing Risk for Concussion in High
School Sports J Primary Prevent (2014) 35: 309.
https://doi-org.ezproxy.library.tufts.edu/10.1007/s10935-014-0355-2
Covassin T, Moran R, Elbin RJ. Sex
differences in reported concussion injury rates and time loss from
participation: an update of the National Collegiate Athletic
Association Injury Surveillance Program from 2004-2005 through
2008-2009. J Athl
Train. 2016;51:189-194.
Wilcox, B. J., Beckwith, J. G., Greenwald, R. M., Raukar, N. P.,
Chu, J. J., McAllister, T. W., … Crisco, J. J. (2015). Biomechanics
of head impacts associated with diagnosed concussion in female
collegiate ice hockey players. Journal of Biomechanics,
48(10), 2201–2204.
Wunderle K, Hoeger KM, Wasserman E, Bazarian
JJ. Menstrual
phase as predictor of outcome after mild traumatic brain injury in
women. J Head Trauma Rehabil. 2014;29: