Researchers have revealed through a study of retired National Football League (NFL) players that those who have a history of concussion with loss of consciousness may be at a greater risk of memory loss – a finding that could pave way for greater understanding of the relation between concussion and brain atrophy.
The research notes that though individuals recover completely from concussion within days or weeks, the potential relation between concussion and the subsequent memory loss at a later stage in life is still an area which is poorly understood.
In the new research, published online by JAMA Neurology, Munro Cullum, Ph.D., a neuropsychologist at the University of Texas Southwestern Medical Center, Dallas, and coauthors have examined the relationship of memory performance with hippocampal volume and with the influence of concussion history in retired NFL athletes with and without mild cognitive impairment (MCI).
For the study, researchers recruited 28 former NFL athletes, eight of which had been diagnosed with MCI and had a history of concussion. The researchers also recruited 21 cognitively healthy control group participants with no history of concussion or past football experience and an additional six control participants with MCI but without history of concussion. Of the 28 retired football players, 17 had reported a grade 3 (G3) concussion with loss of consciousness.
Researchers found that former athletes with concussion history, but without MCI had normal but lower scores on a test of verbal memory compared with control participants, while athletes with a concussion history and MCI performed worse compared with both control participants and athletes without memory impairment. There was no difference in scores between control participants with MCI and athletes with MCI on the test.
Former athletes without a concussion and loss of consciousness showed similar hippocampal volumes compared with control participants across age ranges. However, older retired athletes with at least one concussion with loss of consciousness had smaller hippocampal volumes compared with control subjects and a smaller right hippocampal volume compared with athletes without a G3 concussion. The left hippocampal volume in retired athletes with MCI and concussion also was smaller compared with control participants with MCI.
All of the retired athletes older than 63 years of age with a history of G3 concussion (7 of 7) were diagnosed with MCI and only one former athlete was diagnosed as having MCI but did not have a concussion with loss of consciousness (1 of 5), according to the results. Also, there was no relationship found between the number of games played and MCI, the study reports.
