Longitudinal Developmental Outcomes of Infants and Toddlers With Traumatic Brain Injury.

Importance: Among children, infants and toddlers have some of the highest rates of traumatic brain injury (TBI), but longitudinal information on their developmental outcomes to guide postinjury surveillance is sparse. Objective: To evaluate infants' and toddlers' development over 3 years following TBI compared with those with orthopedic injury (OI). Design, Setting, and Participants: A longitudinal observational cohort study was conducted at 2 level 1 pediatric trauma centers from January 20, 2013, to September 30, 2015; data analysis was performed from May 12 to October 20, 2021. Participants included children injured when younger than 31 months with TBI or OI who received emergency department care. Exposures: Mild, moderate, or severe TBI or OI. Main Outcomes and Measures: Parents completed baseline measures representing preinjury status and 3-, 12-, 24-, and 36-month postinjury status, using the Ages & Stages Questionnaire-3 (ASQ-3), with a mean reference value of 50 and higher scores indicating more advanced development. Linear mixed models characterized children's outcomes for each ASQ-3 domain after adjustment for baseline ASQ-3, injury severity and group, age, injury mechanism (abuse or not), sex, prematurity, family function, social capital, and time. Interactions with time were evaluated. Results: Consent for participation was provided for 195 children; 184 parents (94%) completed a baseline survey. The cohort included 168 children who completed at least 1 follow-up survey: 48 (29%) mild; 54 (32%) complicated mild/moderate; 21 (13%) severe TBI; and 45 (27%) orthopedic injury. The cohort included 95 boys (57%), 49% injured before age 1 year; and 13% injured by abuse. Mean (SD) age at the time of injury was 13.9 (9.4) months. At 36 months, children with mild or complicated mild/moderate TBI performed similarly to children with OI across ASQ-3 domains. Children with severe TBI performed poorly as shown by negative mean differences in communication (-8.8; 95% CI, -13.8 to -3.8); gross motor (-10.1; 95% CI, -15.1 to -5.1); problem solving (-6.6; 95% CI, -11.2 to -1.9), and personal social (-6.3; 95% CI, -10.4 to -2.1) domains with little recovery over time. Children with abusive injury experienced decrements in ability over time in fine motor and personal social skills. Social capital was protective in communication (mean, 1.5; 95% CI, 0.3-2.7) and problem solving (mean, 1.2; 95% CI, 0.1-2.3) domains. Conclusions and Relevance: In this cohort study of children with TBI, children with severe injury showed little recovery. These findings suggest that early childhood intervention is needed, while children with milder injury remained on their developmental track and should continue routine developmental surveillance.