PET scanning of brain tau in retired national football league players: preliminary findings.
OBJECTIVE
Mild traumatic brain injury due to contact sports may cause chronic behavioral, mood, and cognitive disturbances associated with pathological deposition of tau protein found at brain autopsy. To explore whether brain tau deposits can be detected in living retired players, we used positron emission tomography (PET) scans after intravenous injections of 2-(1-{6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile (FDDNP).


METHODS
Five retired National Football League players (age range: 45 to 73 years) with histories of mood and cognitive symptoms received neuropsychiatric evaluations and FDDNP-PET. PET signals in subcortical (caudate, putamen, thalamus, subthalamus, midbrain, cerebellar white matter) and cortical (amygdala, frontal, parietal, posterior cingulate, medial and lateral temporal) regions were compared with those of five male controls of comparable age, education, and body mass index.


RESULTS
FDDNP signals were higher in players compared with controls in all subcortical regions and the amygdala, areas that produce tau deposits following trauma.


CONCLUSIONS
The small sample size and lack of autopsy confirmation warrant larger, more definitive studies, but if future research confirms these initial findings, FDDNP-PET may offer a means for premorbid identification of neurodegeneration in contact-sports athletes.
Department of Psychiatry and Biobehavioral Sciences and Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, CA 90024, USA. gsmall@ucla.edu
Gary W
GW
Small
Vladimir
V
Kepe
Prabha
P
Siddarth
Linda M
LM
Ercoli
David A
DA
Merrill
Natacha
N
Donoghue
Susan Y
SY
Bookheimer
Jacqueline
J
Martinez
Bennet
B
Omalu
Julian
J
Bailes
Jorge R
JR
Barrio
D001265:Athletic Injuries / Q000150:complications / Q000175:diagnosis; D001923:Brain Chemistry; D001930:Brain Injuries / Q000150:complications / Q000175:diagnosis*; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000209:etiology*; D003704:Dementia / Q000175:diagnosis / Q000209:etiology*; D042241:Early Diagnosis; D005538:Football / Q000293:injuries*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019964:Mood Disorders / Q000175:diagnosis / Q000209:etiology*; D009483:Neuropsychological Tests; D009570:Nitriles; D049268:Positron-Emission Tomography / Q000379:methods; D057216:Propensity Score; D016875:tau Proteins / Q000032:analysis*
C444520:2-(1-(6-((2-fluoroethyl)(methyl)amino)-2-naphthyl)ethylidene)malononitrile; D009570:Nitriles; D016875:tau Proteins