Background: Sleep disturbances are a hallmark sign after a sport-related concussion (SRC). Poor sleep has been shown to adversely affect baseline neurocognitive test scores, but it is not comprehensively understood how neurocognitive function is affected by disrupted sleep during recovery from a concussion.
Purpose: To identify the correlation between adolescent athletes' neurocognitive function and their self-reported sleep quantity and sleep disturbance symptoms during recovery from SRC.
Study design: Cross-sectional study; Level of evidence, 3.
Methods: Immediate Post-Concussion Assessment and Cognition Testing (ImPACT) data were retrospectively collected for 545 adolescent athletes treated for SRC at a sports medicine concussion clinic. Patients were stratified into groups based on 2 criteria: self-reported sleep duration and self-reported sleep disturbance symptoms during postinjury ImPACT testing. Sleep duration was classified as short (<7 hours), intermediate (7-9 hours), and long (>9 hours). Sleep disturbance symptoms were self-reported as part of the Post-Concussion Symptom Scale (PCSS) as either sleeping less than normal, sleeping more than normal, or having trouble falling asleep. One-way analyses of variance were conducted to examine the effects that sleep duration as well as self-reported sleep disturbance symptoms had on composite scores. A total of 1067 ImPACT tests were analyzed: test 1, 545; test 2, 380; and test 3, 142.
Results: Sleeping fewer than 7 hours the night before testing correlated with higher PCSS scores (P < .001), whereas sleeping longer than 9 hours correlated with worse visual memory (P = .01), visual motor speed (P <.001), and reaction time (P = .04) composite scores. With regard to self-reported sleep disturbance symptoms, patients demonstrated worse composite scores during ImPACT testing when they self-reported sleeping more than normal (ImPACT test 1: verbal memory, P < .001; visual motor speed, P = .05; reaction time, P = .01; ImPACT test 2: verbal memory, P < .001; visual memory, P < .001; visual motor speed, P < .001; reaction time, P = .01). Adolescent patients recovering from SRC demonstrated higher (worse) PCSS scores (P < .001) when they sensed that their sleep had been disrupted.
Conclusion: Adolescent patients who perceive that their sleep is somehow disrupted after SRC may report a greater number of concussion symptoms during their recovery. In addition, the study results suggest that sleeping more than normal may identify an individual who continues to be actively recovering from concussion, given the correlation between lower neurocognitive function and this self-reported symptom.
Keywords: ImPACT; athletes; concussion; sleep.
© 2014 The Author(s).