Age of first exposure to football and later-life cognitive impairment in former NFL players

Objective: To determine the relationship between exposure to repeated head impacts through tackle football prior to age 12, during a key period of brain development, and later-life executive function, memory, and estimated verbal IQ. Methods: Forty-two former National Football League (NFL) players ages 40–69 from the Diagnosing and Evaluating Traumatic Encephalopathy using Clinical Tests (DETECT) study were matched by age and divided into 2 groups based on their age of first exposure (AFE) to tackle football: AFE <12 and AFE ≥12. Participants completed the Wisconsin Card Sort Test (WCST), Neuropsychological Assessment Battery List Learning test (NAB-LL), and Wide Range Achievement Test, 4th edition (WRAT-4) Reading subtest as part of a larger neuropsychological testing battery. Results: Former NFL players in the AFE <12 group performed significantly worse than the AFE ≥12 group on all measures of the WCST, NAB-LL, and WRAT-4 Reading tests after controlling for total number of years of football played and age at the time of evaluation, indicating executive dysfunction, memory impairment, and lower estimated verbal IQ. Conclusions: There is an association between participation in tackle football prior to age 12 and greater later-life cognitive impairment measured using objective neuropsychological tests. These findings suggest that incurring repeated head impacts during a critical neurodevelopmental period may increase the risk of later-life cognitive impairment. If replicated with larger samples and longitudinal designs, these findings may have implications for safety recommendations for youth sports.

[1]  Alexander Leemans,et al.  Microstructural maturation of the human brain from childhood to adulthood , 2008, NeuroImage.

[2]  R. Kahn,et al.  Genetic associations between intelligence and cortical thickness emerge at the start of puberty , 2014, Human brain mapping.

[3]  J. Rosenfeld,et al.  Intellectual Outcome from Preschool Traumatic Brain Injury: A 5-Year Prospective, Longitudinal Study , 2009, Pediatrics.

[4]  John Chamberlain,et al.  Disclosure , 2010, Annals of Internal Medicine.

[5]  Cornelius Weiller,et al.  Linking planning performance and gray matter density in mid-dorsolateral prefrontal cortex: Moderating effects of age and sex , 2012, NeuroImage.

[6]  D. Zgaljardic,et al.  Neuropsychological Assessment Battery (NAB): Performance in a Sample of Patients with Moderate-to-Severe Traumatic Brain Injury , 2010, Applied neuropsychology.

[7]  H. Levin.  A Compendium of Neuropsychological Tests: Administration, Norms, and Commentary , 1993 .

[8]  A. McKee,et al.  The spectrum of disease in chronic traumatic encephalopathy. , 2013, Brain : a journal of neurology.

[9]  J. Rodgers,et al.  Severity of Alzheimer's disease and effect on premorbid measures of intelligence. , 2006, The British journal of clinical psychology.

[10]  Gerald E. Schneider,et al.  Is it really better to have your brain lesion early? a revision of the “Kennard Principle” , 1979, Neuropsychologia.

[11]  Stephen W Marshall,et al.  Recurrent concussion and risk of depression in retired professional football players. , 2007, Medicine and science in sports and exercise.

[12]  Joseph T. Gwin,et al.  IN VIVO STUDY OF HEAD IMPACTS IN FOOTBALL: A COMPARISON OF NATIONAL COLLEGIATE ATHLETIC ASSOCIATION DIVISION I VERSUS HIGH SCHOOL IMPACTS , 2007, Neurosurgery.

[13]  Allen K. Sills,et al.  Recovery from sports-related concussion: Days to return to neurocognitive baseline in adolescents versus young adults , 2012, Surgical neurology international.

[14]  Jane S. Paulsen,et al.  Estimating premorbid functioning in huntington's disease: the relationship between disease progression and the wide range achievement test reading subtest. , 2011, Archives of clinical neuropsychology : the official journal of the National Academy of Neuropsychologists.

[15]  T. Talavage,et al.  Functionally-detected cognitive impairment in high school football players without clinically-diagnosed concussion. , 2014, Journal of neurotrauma.

[16]  A. McKee,et al.  Self-reported concussion history: impact of providing a definition of concussion , 2014, Open access journal of sports medicine.

[17]  Stefan M. Duma,et al.  Head Impact Exposure in Youth Football , 2012, Annals of Biomedical Engineering.

[18]  Ann C. McKee,et al.  Clinical presentation of chronic traumatic encephalopathy , 2013, Neurology.

[19]  R. Green,et al.  Diagnostic utility of the NAB List Learning test in Alzheimer’s disease and amnestic mild cognitive impairment , 2009, Journal of the International Neuropsychological Society.

[20]  H. Epstein.  Stages of increased cerebral blood flow accompany stages of rapid brain growth , 1999, Brain and Development.

[21]  O. Selnes.  A Compendium of Neuropsychological Tests , 1991, Neurology.

[22]  J. Mazziotta,et al.  Positron emission tomography study of human brain functional development , 1987, Annals of neurology.

[23]  Sylvain Bouix,et al.  Scholarship@Western Scholarship@Western , 2022 .

[24]  Alan C. Evans,et al.  Differences in genetic and environmental influences on the human cerebral cortex associated with development during childhood and adolescence , 2009, Human brain mapping.

[25]  B. Jordan,et al.  Prolonged Effects of Concussion in High School Athletes , 2005, Neurosurgery.

[26]  R. R. Abidin.  Psychological Assessment Resources , 1995 .

[27]  Hisao Nishijo,et al.  Developmental Trajectories of Amygdala and Hippocampus from Infancy to Early Adulthood in Healthy Individuals , 2012, PloS one.

[28]  Alan C. Evans,et al.  Intellectual ability and cortical development in children and adolescents , 2006, Nature.

[29]  D. Hovda,et al.  Experience-dependent behavioral plasticity is disturbed following traumatic injury to the immature brain , 2005, Behavioural Brain Research.

[30]  Alan C. Evans,et al.  Brain development during childhood and adolescence: a longitudinal MRI study , 1999, Nature Neuroscience.

[31]  Christine M Baugh,et al.  Clinical subtypes of chronic traumatic encephalopathy: literature review and proposed research diagnostic criteria for traumatic encephalopathy syndrome , 2014, Alzheimer's Research & Therapy.

[32]  Y. Stern,et al.  Acculturation, Reading Level, and Neuropsychological Test Performance Among African American Elders , 2004, Applied neuropsychology.

[33]  S. Blakemore,et al.  Development of the adolescent brain: implications for executive function and social cognition. , 2006 .

[34]  Amanda Wood,et al.  Do children really recover better? Neurobehavioural plasticity after early brain insult. , 2011, Brain : a journal of neurology.

[35]  A. McKee,et al.  Profile of self-reported problems with executive functioning in college and professional football players. , 2013, Journal of neurotrauma.

[36]  S. Marshall,et al.  Association between Recurrent Concussion and Late-Life Cognitive Impairment in Retired Professional Football Players , 2005, Neurosurgery.

[37]  D. Pennell,et al.  Functional abnormalities in normally appearing athletes following mild traumatic brain injury: a functional MRI study , 2010, Experimental Brain Research.

[38]  Tong Zhu,et al.  Persistent, Long-term Cerebral White Matter Changes after Sports-Related Repetitive Head Impacts , 2014, PloS one.

[39]  Joseph A. Maldjian,et al.  Head Impact Exposure in Youth Football: Elementary School Ages 9–12 Years and the Effect of Practice Structure , 2013, Annals of Biomedical Engineering.