Neurochemical aftermath of amateur boxing.
BACKGROUND
Little solid information is available on the possible risks for neuronal injury in amateur boxing.


OBJECTIVE
To determine whether amateur boxing and severity of hits are associated with elevated levels of biochemical markers for neuronal injury in cerebrospinal fluid.


METHODS
Longitudinal study.


METHODS
Referral center specializing in evaluation of neurodegenerative disorders.


METHODS
Fourteen amateur boxers (11 men and 3 women) and 10 healthy male nonathletic control subjects.


METHODS
The boxers underwent lumbar puncture 7 to 10 days and 3 months after a bout. The control subjects underwent LP once.


METHODS
Neurofilament light protein, total tau, glial fibrillary acidic protein, phosphorylated tau, and beta-amyloid protein 1-40 (Abeta([1-40])) and 1-42 (Abeta([1-42])) concentrations in cerebrospinal fluid were measured.


RESULTS
Increased levels after a bout compared with after 3 months of rest from boxing were found for 2 markers for neuronal and axonal injury, neurofilament light protein (mean +/- SD, 845 +/- 1140 ng/L vs 208 +/- 108 ng/L; P = .008) and total tau (mean +/- SD, 449 +/- 176 ng/L vs 306 +/- 78 ng/L; P = .006), and for the astroglial injury marker glial fibrillary acidic protein (mean +/- SD, 541 +/- 199 ng/L vs 405 +/- 138 ng/L; P = .003). The increase was significantly higher among boxers who had received many hits (>15) or high-impact hits to the head compared with boxers who reported few hits. In the boxers, concentrations of neurofilament light protein and glial fibrillary acidic protein, but not total tau, were significantly elevated after a bout compared with the nonathletic control subjects. With the exception of neurofilament light protein, there were no significant differences between boxers after 3 months of rest from boxing and the nonathletic control subjects.


CONCLUSIONS
Amateur boxing is associated with acute neuronal and astroglial injury. If verified in longitudinal studies with extensive follow-up regarding the clinical outcome, analyses of cerebrospinal fluid may provide a scientific basis for medical counseling of athletes after boxing or head injury.
Zetterberg
Henrik
H
Department of Experimental Neuroscience, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. henrik.zetterberg@clinchem.gu.se
Hietala
M Albert
MA
Jonsson
Michael
M
Andreasen
Niels
N
Styrud
Ewa
E
Karlsson
Ingvar
I
Edman
Ake
A
Popa
Cornel
C
Rasulzada
Abdullah
A
Wahlund
Lars-Olof
LO
Mehta
Pankaj D
PD
Rosengren
Lars
L
Blennow
Kaj
K
Wallin
Anders
A
D000293:Adolescent; D000328:Adult; D001914:Boxing / Q000293:injuries*; D001923:Brain Chemistry; D006259:Craniocerebral Trauma / Q000134:cerebrospinal fluid*; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000134:cerebrospinal fluid*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D016900:Neurofilament Proteins / Q000134:cerebrospinal fluid*; D018709:Statistics, Nonparametric; D013997:Time Factors
D005904:Glial Fibrillary Acidic Protein; D016900:Neurofilament Proteins