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Examining the Use of a Rest-Activity Ratio in a Pediatric Rehabilitation Setting
Anthony H Lequerica1, Hannah Aura Shoval2, Krishan Yalamanchi3
1Center for Traumatic Brain Injury Research, Kessler Foundation, East Hanover, NJ; Department of Physical Medicine and Rehabilitation, Rutgers-New Jersey Medical School, Newark, NJ.
Insights
Children with acquired brain injuries (ABI) show poorer sleep-wake regulation, indicated by lower rest-activity ratios. This measure is sensitive to neurocognitive deficits in pediatric rehabilitation.
Area of Science:
- Pediatric Rehabilitation
- Neuroscience
- Sleep Medicine
Background:
- Acquired brain injury (ABI) can significantly impact neurocognitive function and sleep-wake regulation in children.
- Actigraphy is a non-invasive method to objectively measure sleep-wake patterns.
Purpose of the Study:
- To investigate the relationship between actigraphy-derived sleep-wake regulation and neurocognitive dysfunction in pediatric rehabilitation patients.
- To determine if sleep-wake regulation is sensitive to acquired brain injury in this population.
Main Methods:
- A cross-sectional study involving 43 pediatric inpatients (ages 8-17) at a rehabilitation facility.
- Participants wore an actigraph for one week to derive a rest-activity ratio.
- Brain injury status (traumatic, non-traumatic ABI, or control) and functional status (WeeFIM Cognitive and Motor scores) were assessed.
Main Results:
- Unadjusted analyses revealed significantly lower rest-activity ratios in both traumatic and non-traumatic ABI groups compared to controls.
- After adjusting for cognitive and motor scores, the main group effect was no longer significant.
- A significant relationship was found between the rest-activity ratio and cognitive scores at admission.
Conclusions:
- Lower rest-activity ratios correlate with poorer functional status, particularly in the cognitive domain, suggesting impaired sleep-wake regulation in pediatric ABI patients.
- The rest-activity ratio may be a useful tool for monitoring sleep-wake regulation in pediatric rehabilitation.
- Further research is needed to assess its sensitivity to change and responsiveness to interventions.
Objective:
To examine the relationship between an estimate of sleep-wake regulation derived from actigraphy and determine whether it would be sensitive to neurocognitive dysfunction associated with acquired brain injury (ABI) in a pediatric rehabilitation sample.
Design:
Cross-sectional design.
Setting:
Inpatient pediatric rehabilitation facility.
Participants:
A sample (N=43) of 31 males (72.1%) and 12 females (27.9%) admitted to a pediatric rehabilitation hospital wore an actigraph (wrist accelerometer) for 1 week. Participant ages ranged from 8 to 17 years (mean, 13.1y; SD, 2.7y).
Interventions:
Not applicable.
Main Outcome Measures:
Raw actigraphy activity counts in 1-minute epochs were used to derive a rest-activity ratio over each 24-hour period; a 5-day average value was calculated for Monday through Friday. Brain injury status was derived through medical record review, resulting in the formation of 3 groups: traumatic brain injury (n=14), nontraumatic brain injury (n=16), and a non-ABI control group (n=13). Functional status was measured using FIM for children (WeeFIM) Cognitive and Motor scores extracted from the medical records.
Results:
Unadjusted models showed a significant main group effect for brain injury status (P=.012). Compared with controls, the rest-activity ratio was significantly lower in both the traumatic brain injury (P=.005), and nontraumatic brain injury (P=.023) groups. However, the main group effect was no longer significant in an adjusted model controlling for WeeFIM Cognitive and WeeFIM Motor scores at admission. In the context of the adjusted model, there was a significant relationship between the rest-activity ratio and WeeFIM Cognitive scores at admission.
Conclusions:
Individuals with lower functional status at admission, especially in the cognitive domain, had lower rest-activity ratios, suggesting poorer sleep-wake regulation. Similar to findings in adults with ABI, this ratio may have utility in tracking sleep-wake regulation in the pediatric rehabilitation setting. Future studies should investigate sensitivity to change over the course of recovery and responsiveness to clinical interventions to improve sleep.
