Actigraphy-based characterization of nighttime repositioning in individuals with spinal cord injury living in the community setting to facilitate pressure injury risk assessment

Study design: Observational cohort study. Objectives: To introduce an actigraphy-based method for objectively measuring in-bed mobility during sleep in individuals with spinal cord injury (SCI) living in the community, and to assess the feasibility and safety of this approach, as well as its association with pressure injury (PI) incidence. Setting: Community-dwelling individuals with traumatic SCI. Methods: Nighttime repositioning habits were assessed in 28 individuals with traumatic SCI, of whom 20 were included in the final analysis. An actigraph placed on the sternum recorded in-bed repositioning frequency and time spent in different positions for up to 14 consecutive nights. Results: Participants spent most of their sleep time in the supine (73%) or lateral (25%) position. In-bed repositioning occurred at an average of 2.2 ± 2.4 times per night, with large interindividual variability reflecting heterogeneous neurological levels and functional status. Only 10% of subjects repositioned at least once every 3 hours during the night. Within 1 year, 40% of individuals developed a PI, and these participants had repositioned significantly less frequently at night compared with those without PI (1 ± 1 vs. 3 ± 2 instances of repositioning per night, P = 0.01). Conclusion: Actigraphy provides a safe and objective method for assessing nocturnal repositioning behaviors in community-dwelling individuals with SCI. Reduced nighttime repositioning frequency was associated with a higher incidence of PI, supporting the clinical utility of objective mobility assessment for PI risk evaluation.