Predictors of Cognitive Function and Recovery 10 Years after Traumatic Brain Injury in Young Children

Traumatic brain injury (TBI) is one of the leading causes of disrupted development in childhood. Previous studies have demonstrated that severe injury at a young age is associated with poorer outcomes at least 5 years post-injury. This was a prospective longitudinal study that compared recovery of cognitive and functional skills in 40 children with early childhood TBI to 10 years post-injury to healthy controls. The researchers recruited 40 children with TBI from their previously reported study and divided them into three groups based on injury severity: mild, moderate, or severe (as determined by Glasgow Coma Scale cutoffs or presence of neurologic deficit) and compared them to 16 healthy controls with respect to the following measures: cognition (using Wechsler Intelligence Scale for Children [WIS-IQ]), adaptive ability (using Adaptive Behavior Assessment System [ABAS-II]), executive function (using Behavior Rating Inventory of Executive Function [BRIEF]) and social skills (using Social Skills Rating System [SSRS]) at four times post-injury: 1 (0–3 months), 2 (12 months), 3 (30 months), and 4 (10 years). The study also attempted to identify predictors of recovery, including environmental factors: socioeconomic status (SES) and family functioning (using Family Functioning questionnaire [FFQ]) and pre-injury characteristics (using Vineland Adaptive Behavior scales [VABS]). The study showed significant difference in children with severe TBI vs. the control group in cognition as measured by WIS-Full Scale IQ (FSIQ), at time 1, F(3, 55) = 3.36, p = 0.03 and time 4, F(3, 55) = 4.63, p = 0.01. With respect to predictors of 10-year outcomes (time 4), pre-injury characteristics (VABS) was highly correlated with cognition (all IQ variables) as well as adaptive abilily (ABAS), β = 0.57, t = 2.52, p = 0.03. Family functioning (FFQ) was also significantly predictive of recovery of social skills (SSRS) at 10 years, β = 0.51, t = 2.15, p = 0.05. When plotting recovery trajectories, although children with severe TBI demonstrated the lowest mean scores at all time points on all IQ measures, there was no evidence of severity-related differences in recovery rate. Although the study confirmed findings from prior studies that severe TBI in early childhood is associated with persistent deficits, it suggests two new concepts: 1) there may be an “injury threshold” beneath which children may escape serious sequelae, and 2) the recovery trajectories plateau from 5 to 10 years for all groups, regardless of the injury severity, implying that although children with early severe TBI may never “catch up” to their peers, the gap does not widen during this period.