The effect of persistent post-concussive symptoms on cognitive performance after sport concussion

Abstract

ObjectiveWe aim to study the effect of persistent post-concussive symptoms on cognitive performance of elite athletes, based on the hypothesis that persistent symptoms could impair athletes’ cognitive performances and functional outcomes.DesignProspective observational and longitudinal case control study.SettingUniversity research centre, single centre.Participants7 athletes with persistent symptoms (>2 weeks, assessed at median 31 days post-concussion), 10 athletes with brief symptoms (<3 days, assessed within a week, median 3.5 days), and 9 age-matched healthy volunteers. Inclusion criteria: male/female athletes (aged 18–40) in contact sports who sustained concussion(s) recently, being symptomatic with normal neuro-radiological findings at enrolment.InterventionIndependent variables: post-concussive symptom scores and duration of symptoms.Outcome measuresMulti-dimensional scores from Sport Concussion Assessment Tool III, Immediate Post-concussion Assessment and Cognitive Testing, WAIS symbol search and digit span backward tests.Main resultsPatients with persistent symptoms scored less in the symbol search test than those with brief symptoms and the healthy volunteers (grouping effect p=0.006; post hoc tests p=0.039 and 0.004, respectively). In all 17 patients, symptom scores correlated with reaction time (ρ=−0.61, p=0.009), and visual motor speed correlated with symbol search scores (ρ=0.59, p=0.013). 6 patients who completed follow-up assessments when symptom-free showed improvement in their symbol search scores (p=0.042) and visual memory (p=0.028).ConclusionsConcussed athletes with persistent symptoms performed poorly in visual perception/analysis and information processing. Persistent post-concussive symptoms could affect athletes’ visual memory, perception/analysis, reaction time and information processing speed, thus precipitating them to further injuries should they return to play prematurely.Competing interestsNone.