Objectives Examine whether objective sleep outcomes associate with cognitive performance assessed by tools (i.e., Sport Concussion Assessment Tool [SCAT5]; Immediate Post-Concussion Assessment Testing [ImPACT]) used to support clinical decision-making for sports-related concussion. Methods Participants’ (n = 20) sleep was monitored for 4-5 nights with a dry-electroencephalography device prior to baseline SCAT5 and ImPACT testing. Sleep measures included total sleep time, sleep efficiency, and sleep stage proportions (N1%, N2%, N3%, REM%). Cognitive outcomes included SCAT5 orientation, immediate memory, concentration, and delayed recall, and ImPACT verbal memory, visual memory, visual motor speed and reaction time. Results Spearman's rank correlations revealed REM% was strongly correlated with subsequent SCAT5 Concentration score (ρ = 0.71, p < 0.001). Exploratory regression indicated mean REM% was predictive of SCAT5 Concentration (β = 0.49; 95%CI = 0.14, 0.85; OR = 1.64; p = 0.006). Conclusions SCAT5 Concentration performance was associated with prior REM%. Significant REM sleep loss may confound subsequent SCAT Concentration testing; however, more research is needed to elucidate any potential effects on overall SCAT neurocognitive testing outcomes. When interpreting SCAT neurocognitive outcomes, clinicians should consider whether players have experienced significant/major pre-test sleep disturbances.
