title: Altered Neurochemistry in Former Professional Soccer Players without a History of Concussion.
abstract: Soccer is played by more than 250 million people worldwide. Repeatedly heading the ball may place soccer players at high risk for repetitive subconcussive head impacts (RSHI). This study evaluates the long-term effects of RSHI on neurochemistry in athletes without a history of clinically diagnosed concussion, but with a high exposure to RSHI. Eleven former professional soccer players (mean age 52.0±6.8 years) and a comparison cohort of 14 age- and gender-matched, former non-contact sport athletes (mean age 46.9±7.9 years) underwent 3T magnetic resonance spectroscopy (MRS) and neurocognitive evaluation. In the soccer players a significant increase was observed in both choline (Cho), a membrane marker, and myo-inositol (ml), a marker of glial activation, compared with control athletes. Additionally, ml and glutathione (GSH) were significantly correlated with lifetime estimate of RSHI within the soccer group. There was no significant difference in neurocognitive tests between groups. Results of this study suggest an association between RSHI in soccer players and MRS markers of neuroinflammation, suggesting that even subconcussive head impacts affect the neurochemistry of the brain and may precede neurocognitive changes. Future studies will need to determine the role of neuroinflammation in RSHI and the effect on neurocognitive function.
authors.affiliation: 1 Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .|3 Department of Child and Adolescent Psychiatry, Psychosomatic, and Psychotherapy, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Inga K
authors.initials: IK
authors.lastname: Koerte
authors.affiliation: 1 Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|4 Department of Radiology, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.
authors.forename: Alexander P
authors.initials: AP
authors.lastname: Lin
authors.affiliation: 1 Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .|3 Department of Child and Adolescent Psychiatry, Psychosomatic, and Psychotherapy, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Marc
authors.initials: M
authors.lastname: Muehlmann
authors.affiliation: 4 Department of Radiology, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.
authors.forename: Sai
authors.initials: S
authors.lastname: Merugumala
authors.affiliation: 4 Department of Radiology, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.
authors.forename: Huijun
authors.initials: H
authors.lastname: Liao
authors.affiliation: 4 Department of Radiology, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.
authors.forename: Tyler
authors.initials: T
authors.lastname: Starr
authors.affiliation: 2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .|5 Department of Radiology, Charité Berlin , Berlin, Germany .
authors.forename: David
authors.initials: D
authors.lastname: Kaufmann
authors.affiliation: 1 Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Michael
authors.initials: M
authors.lastname: Mayinger
authors.affiliation: 2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Denise
authors.initials: D
authors.lastname: Steffinger
authors.affiliation: 2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Barbara
authors.initials: B
authors.lastname: Fisch
authors.affiliation: 6 Department of Psychiatry, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Susanne
authors.initials: S
authors.lastname: Karch
authors.affiliation: 7 Department of Pediatric Neurology, Dr. von Hauner Children's Hospital, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Florian
authors.initials: F
authors.lastname: Heinen
authors.affiliation: 2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Birgit
authors.initials: B
authors.lastname: Ertl-Wagner
authors.affiliation: 2 Institute for Clinical Radiology, Ludwig-Maximilian-University , Munich, Germany .
authors.forename: Maximilian
authors.initials: M
authors.lastname: Reiser
authors.affiliation: 8 Departments of Neurology, Neurosurgery, and Anatomy and Neurobiology, Boston University Alzheimer's Disease Center, Boston University School of Medicine , Boston, Massachusetts.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Stern
authors.affiliation: 9 Spaulding Rehabilitation Hospital, Massachusetts General Hospital, Brigham and Women's Hospital, Department of Physical Medicine and Rehabilitation, Harvard Medical School , Boston, Massachusetts.
authors.forename: Ross
authors.initials: R
authors.lastname: Zafonte
authors.affiliation: 1 Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|4 Department of Radiology, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|10 Department of Psychiatry, Brigham and Women's Hospital, and Harvard Medical School , Boston, Massachusetts.|11 VA Boston Healthcare System , Boston, Massachusetts.
authors.forename: Martha E
authors.initials: ME
authors.lastname: Shenton
mesh_terms: D000328:Adult; D056352:Athletes; D001265:Athletic Injuries / Q000175:diagnosis*; D001923:Brain Chemistry; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000175:diagnosis*; D012916:Soccer
keywords: MR spectroscopy; brain metabolism; repetitive subconcussive brain trauma; soccer
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