ABSTRACT: Cerebral concussion is common in collision sports such as football, yet the chronic neurological effects of recurrent concussion are not well understood. The purpose of our study was to investigate the association between previous head injury and the likelihood of developing mild cognitive impairment (MCI) and Alzheimer's disease in a unique group of retired professional football players with previous head injury exposure.
A general health questionnaire was completed by 2552 retired professional football players with an average age of 53.8 (+/-13.4) years and an average professional football playing career of 6.6 (+/- 3.6) years. A second questionnaire focusing on memory and issues related to MCI was then completed by a subset of 758 retired professional football players (> or = 50 yr of age). Results on MCI were then cross-tabulated with results from the original health questionnaire for this subset of older retirees.
Of the former players, 61% sustained at least one concussion during their professional football career, and 24% sustained three or more concussions. Statistical analysis of the data identified an association between recurrent concussion and clinically diagnosed MCI (chi = 7.82, df = 2, P = 0.02) and self-reported significant memory impairments (chi = 19.75, df = 2, P = 0.001). Retired players with three or more reported concussions had a fivefold prevalence of MCI diagnosis and a threefold prevalence of reported significant memory problems compared with retirees without a history of concussion. Although there was not an association between recurrent concussion and Alzheimer's disease, we observed an earlier onset of Alzheimer's disease in the retirees than in the general American male population.
Our findings suggest that the onset of dementia-related syndromes may be initiated by repetitive cerebral concussions in professional football players.
Neurosurgery 10/2005; 57(4):719-26; discussion 719-26. · 2.79 Impact Factor
ABSTRACT: To identify enduring prolonged neuropsychological effects of cerebral concussion in high school youth athletes.
High school athletes (n = 223) underwent baseline neuropsychological evaluation between 1999 and 2000, assigned to independent groups on the basis of concussion history: athletes with no concussion history or present medical and/or neuropsychological complaints (n = 82), symptom-free athletes who experienced one (n = 56) or two or more (n = 45) concussions (not in the prior 6 mo), and those who experienced a concussion 1 week before testing (n = 40). Main outcome measures included a structured clinical interview, demographic form, symptom checklist, the Repeatable Battery for the Assessment of Neuropsychological Status, and the Trail Making Tests A and B. Analyses of variance were used to determine between-group differences.
Athletes with recent concussions performed significantly worse on measures of attention and concentration than youth athletes with no concussion history. Symptom-free athletes with a history of two or more concussions performed similar on testing to youth athletes who had just experienced a recent concussion. Similarly, cumulative academic grade point averages were significantly lower not only for youth athletes with two or more previous concussion groups, but for youth athletes who experienced recent concussions, suggesting that athletes with lower grade point averages may be more prone to concussion.
There seem to be subtle yet significant prolonged neuropsychological effects in youth athletes with a history of two or more previous concussions.
Neurosurgery 09/2005; 57(2):300-6; discussion 300-6. · 2.79 Impact Factor
Advances in neurology 02/2002; 90:75-85.