Trajectories of sleep changes during the acute phase of traumatic brain injury: a 7-day actigraphy study

Abstract

Background/purpose: To examine trajectories of change in sleep during the acute phase of traumatic brain injury (TBI), and whether specific demographic and disease characteristics predicted the initial levels of sleep and the trajectories of change in sleep parameters.

Methods: This was a prospective observational study. Fifty-two patients with first-ever TBI were enrolled. Sleep parameters were measured using actigraphy for 7 consecutive days after admission. Hierarchical linear modeling was used for data analyses in 52 TBI patients and in a subgroup of mild TBI patients (n = 31).

Results: Participants had significant lower sleep efficiency, longer wake time after sleep onset, and longer 24-hour total sleep time (TST) than the normative data (all p < 0.05). Seventy-two percent of participants experienced prolonged 24-hour TST. Both daytime and 24-hour TST showed a significant downward trend across the study period. An initial Glasgow Coma Scale score < 11 significantly predicted the slope of change of daytime TST over time. Without initial loss of consciousness and age < 40 years were independent predictors of the change pattern of 24-hour TST over time. In the mild TBI subgroup, 24-hour TST significantly and gradually declined over time. Gender significantly predicted the trajectory of 24-hour sleep duration.

Conclusion: Poor sleep efficiency and longer sleep duration are common symptoms in acute TBI patients. Both head injury severity and age predicted the trajectories of daytime and 24-hour sleep duration during the acute phase of TBI, whereas gender predicted the trajectories of 24-hour sleep duration in the mild TBI subgroup.

Keywords: hierarchical linear model; sleep; symptom trajectory; traumatic brain injury.