Relationship between concussion and neuropsychological performance in college football players

Context Despite the high prevalence and potentially serious outcomes associ ated with concussion in athletes, there is little systematic research exami ning risk factors and short- and long-term outcomes. Objectives To assess the relationship between concussion history and learni ng disability (LD) and the association of these variables with neuropsychol ogical performance and to evaluate postconcussion recovery in a sample of c ollege football players. Design, Setting, and Participants A total of 393 athletes from 4 university football programs across the United States received preseason baseline eva luations between May 1997 and February 1999. Subjects who had subsequent fo otball-related acute concussions (n = 16) underwent neuropsychological comp arison with matched control athletes from within the sample (n = 10). Main Outcome Measures Clinical interview, 8 neuropsychological measures, an d concussion symptom scale ratings at baseline and after concussion. Results Of the 393 players, 129 (34%) had experienced 1 previous concussion and 79 (20%) had experienced 2 or more concussions. Multivariate analysis of variance yielded significant main effects for both LD (P<.001) and concu ssion history (P = .009), resulting in lowered baseline neuropsychological performance. A significant interaction was found between LD and history of multiple concussions and LD on 2 neurol psychological measures (Trail-Makin g Test, Form B [P = .007] and Symbol Digit Modalities Test [P = .009]), ind icating poorer performance for the group with LD and multiple concussions c ompared with other groups. A discriminant function analysis using neuropsyc hological testing of athletes 24 hours after acute in-season concussion com pared with controls resulted in an overall 89.5% correct classification rat e. Conclusions Our study suggests that neuropsychological assessment is a usef ul indicator of cognitive functioning in athletes and that bath history of multiple concussions and LD are associated with reduced cognitive performan ce. These variables may be detrimentally synergistic and should receive fur ther study.