LAUSR

Fatigue may be among the most profound and debilitating consequences of pediatric traumatic brain injury (TBI); however, neurostructural risk factors associated with post-injury fatigue remain elusive. This prospective study aimed to evaluate the independent value of susceptibility-weighted imaging (SWI) biomarkers, over-and-above known risk factors, to predict fatigue symptom severity in children with TBI. 42 children were examined with structural magnetic-resonance imaging (sMRI), including a SWI sequence, within 8-weeks post-injury. The PedsQL Multi-Dimensional Fatigue Scale (MFS) was administered 24-months post-injury. Compared to population expectations, the TBI group displayed significantly higher levels of general fatigue (Cohen's d = 0.44), cognitive fatigue (Cohen's d = 0.59), sleep/rest fatigue (Cohen's d = 0.37), and total fatigue (Cohen's d = 0.63). In multi-variate models adjusted for TBI severity, child demographic factors and depression, sub-acute volume of SWI lesions was independently associated with all fatigue symptom domains. The magnitude of the brain-behavior relationship varied by fatigue symptom domain, such that the strongest relationships were observed for the cognitive fatigue and total fatigue symptom scales. Overall, we found that total volume of SWI lesions explained up to 24% additional variance in multi-dimensional fatigue, over-and-above known risk factors. SWI has potential to improve prediction of post-injury fatigue in children with TBI. Our preliminary findings suggest that volume of SWI lesions may represent a novel, independent biomarker of post-injury fatigue scores, which could help to identify high-risk children who are likely to benefit from targeted psychoeducation and/or preventive strategies to minimize risk of persisting fatigue.