Pediatric TBI & Cognitive Fatigue

TRAUMATIC BRAIN INJURY (TBI) in childhood is known to cause acute and chronic changes in development and functioning. Up to 60% of children with TBI experience the symptom of fatigue chronically post-injury when attempting to participate in daily life. Fatigue can be challenging to measure, particularly in individuals with TBI, due to its subjective nature.

To best understand fatigue after TBI, the influence of neurobiological and personal-contextual factors on multiple fatigue dimensions must be considered.

The neurological and biological changes occurring chronically and acutely after a TBI are often associated with decreased physical, cognitive, emotional, and sleep functioning. Individuals with TBI than must exert increased effort to complete daily life tasks, ultimately evoking fatigue more quickly and more often than individuals without TBI.

Post-TBI, children commonly experience deficits in cognition and executive functioning. In light of these deficits, children often report feeling mentally or cognitively fatigued when attempting to participate in typical academic and social activities; this is sometimes referred to as feeling “mentally foggy."

Cognitive fatigue, as defined by Wylie and Flashman, is a “transient increase in mental exhaustion resulting from prolonged periods of cognitive activity.” When experiencing cognitive fatigue, other cognitive symptoms (eg, slower processing time) might be exacerbated, increasing the child's frustration and decreasing their motivation to participate. Ultimately, the child disengages academically and socially.

Due to the lack of discussion of cognitive fatigue in experimental studies and review articles, it remains difficult for researchers and clinicians to draw conclusions about the prevalence of and assessment and management strategies for cognitive fatigue after childhood TBI.

Postinjury functioning (eg, sleep, physical, emotional, and daily participation), brain volume, age at onset, parental marriage status, and quality of life appear to be associated with cognitive fatigue, but the directions of these relations remain unclear.

Studies suggested that adolescence is a particularly important time to evaluate and consider fatigue, due to the natural increase of fatigue during that developmental period. In addition, early childhood presents with the highest rates of TBI across childhood with major cognitive and developmental changes shortly after injury.

Suggestions for assessment of cognitive fatigue in childhood TBI included:

--> regular and systematic screenings for symptoms into the chronic stages of recovery to track progress and ongoing needs

--> multidimensional fatigue assessments with multiple reporters

--> structural imaging of biomarkers to identify and predict cognitive fatigue

--> and self-report assessments specific to the child's developmental stage.

Recommendations for interventions included:

--> treat both the cognitive fatigue symptoms and areas of functioning associated with greater fatigue (eg, physical skills);

--> support functional improvements for participation and quality of life through cognitive rehabilitation, behavior management, and academic supports;

--> and consider external demands based on age when designing supports and implementing services (Riccardi & Ciccia, 2021).

Cognitive fatigue results in recent TBI metanalysis:

-->41.4% (2.7 average rating) reported “feeling mentally foggy” at initial visit; 19.1% (1.6 average rating) reported at follow-up visits

-->Children who participated in a closely monitored, active rehabilitation treatment program did not experience more adverse effects than those receiving treatment as usual. No significant changes were observed between physical activity, symptom exacerbation, and clinical outcomes.

-->Cognitive fatigue was significantly worse for children with moderate-severe TBI than mild TBI. Cognitive fatigue worsened significantly from 6 to 12 mo post-injury.

-->At 6 and 12 mo post-TBI, 10% and 17%, of children with mild TBI and 27% and 19% of children with moderate-severe TBI were rated in the clinical range for total fatigue, respectively (cognitive fatigue levels were not individually reported).

-->Cognitive fatigue and all fatigue measures improved significantly post-treatment in an active rehabilitation program.

-->41.4% (2.7 average rating) reported “feeling mentally foggy” at initial visit; 19.1% (1.6 average rating) reported at follow-up visits

-->Children who participated in a closely monitored, active rehabilitation treatment program did not experience more adverse effects than those receiving treatment as usual. No significant changes were observed between physical activity, symptom exacerbation, and clinical outcomes.

**Cognitive fatigue was significantly associated with smaller brain volumes. This finding could indicate disruptions of neural pathways cause an imbalance in effort-reward experiences, which is subjectively reported as cognitive fatigue.

**Greater levels of cognitive fatigue were significantly associated with older age at onset (>11 y); single-parent household; greater limitations in activities and participation; and lower quality of life.

Reference:

Riccardi, J. S., & Ciccia, A. (2021). Cognitive fatigue in pediatric traumatic brain injury: A meta-analysis and scoping review. Journal of Head Trauma Rehabilitation, 36(4), 226–241. https://doi.org/10.1097/htr.0000000000000644