title: The Relationship Between Sleep-Wake Cycle Disturbance and Trajectory of Cognitive Recovery During Acute Traumatic Brain Injury.
abstract: OBJECTIVE
  Following traumatic brain injury, both sleep dysfunction and cognitive impairment are common. Unfortunately, little is known regarding the potential associations between these 2 symptoms during acute recovery. This study sought to prospectively examine the relationship between ratings of sleep dysfunction and serial cognitive assessments among traumatic brain injury acute neurorehabilitation admissions.
  
  
  METHODS
  Participants were consecutive admissions to a free-standing rehabilitation hospital following moderate to severe traumatic brain injury (Median Emergency Department Glasgow Coma Scale = 7). Participants were assessed for sleep-wake cycle disturbance (SWCD) and cognitive functioning at admission and with subsequent weekly examinations. Participants were grouped on the basis of presence (SWCD+) or absence (SWCD-) of sleep dysfunction for each examination; groups were equivalent on demographic and injury variables. Individual Growth Curve modeling was used to examine course of Cognitive Test for Delirium performance across examinations.
  
  
  RESULTS
  Individual Growth Curve modeling revealed a significant interaction between examination number (ie, time) and SWCD group (β = -4.03, P < .001) on total Cognitive Test for Delirium score. The SWCD+ ratings on later examinations were predicted to result in lower Cognitive Test for Delirium scores and greater cognitive impairment over time.
  
  
  CONCLUSIONS
  This study has implications for improving neurorehabilitation treatment, as targeting sleep dysfunction for early intervention may facilitate cognitive recovery.
authors.affiliation: TIRR Memorial Hermann, Houston, Texas (Drs Holcomb and Sherer); Mental Health and Behavioral Sciences (MHBS) (Drs Kamper and Nakase-Richardson), Center of Innovation in Disability Rehabilitation and Research (CINDRR) (Drs Barnett and Nakase-Richardson), and Defense and Veterans Brain Injury Center (DVBIC) (Dr Nakase-Richardson), James A. Haley Veterans' Hospital, Tampa, Florida; Department of Medicine, University of South Florida, Tampa (Dr Nakase-Richardson); Geisel School of Medicine at Dartmouth, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (Dr Towns) and Methodist Rehabilitation Center, Jackson, Mississippi (Dr Evans).
authors.forename: Erin M
authors.initials: EM
authors.lastname: Holcomb
authors.forename: Stephanie
authors.initials: S
authors.lastname: Towns
authors.forename: Joel E
authors.initials: JE
authors.lastname: Kamper
authors.forename: Scott D
authors.initials: SD
authors.lastname: Barnett
authors.forename: Mark
authors.initials: M
authors.lastname: Sherer
authors.forename: Clea
authors.initials: C
authors.lastname: Evans
authors.forename: Risa
authors.initials: R
authors.lastname: Nakase-Richardson
mesh_terms: D000328:Adult; D000070642:Brain Injuries, Traumatic / Q000150:complications* / Q000523:psychology* / Q000534:rehabilitation; D003072:Cognition Disorders / Q000209:etiology*; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020127:Recovery of Function; D012893:Sleep Wake Disorders / Q000209:etiology*; D013997:Time Factors; D055815:Young Adult