ABSTRACT 365

Abstract

Background and aims: When parents are asked to describe their long-term concerns for their child with TBI, they often target executive dysfunction. Executive functions (EFs) are those cognitive abilities that regulate, control, and manage other cognitive processes. The mechanism of TBI-related EF changes is not well understood. Aims: We assessed the pattern of EF changes over the first year post-injury, including what EFs are affected, whether and how they recover, and potential predictors of these changes. Methods: 53 youth, age 5 to 18 years, who had sustained complicated mild to severe TBIs were recruited from five children’s hospitals in Canada (Institutional Review Boards provided approval of the study). Parents completed rating of EF symptoms (Behaviour Rating Inventory of Executive Function) at time of injury (baseline) and at 3, 6, and 12 months post-injury. Serum protein and brain neuroimaging analysis provided potential biomarkers of TBI-related EF changes. Results: Parent reports of EF changes are heterogeneous following pediatric TBI with some abilities reportedly minimally affected (inhibition, planning, organization), while others exhibit decline in the first 3 months (working memory and initiation) or 6 months (emotional control, flexibility, and monitoring behaviour). Many EFs fail to fully recover one year following injury. Serum and brain biomarkers may predict persisting changes in EF. Conclusions: An acute brain MRI and serum biomarkers of brain injury may be important prognostic tools for predicting the course of EF changes following TBI, which is important for patients and their families because EFs are known to affect cognitive processes (memory and attention), academic achievement, and behaviour regulation.