Postconcussive Symptoms After Early Childhood Concussion
Authors: Dupont Dominique , Tang Ken , Beaudoin Cindy , Dégeilh Fanny , Gagnon Isabelle , Yeates Keith Owen , Rose Sean C. , Gravel Jocelyn , Burstein Brett , Stang Antonia S. , Stanley Rachel M. , Zemek Roger L. , Beauchamp Miriam H. ,   PERC KOALA Study, Bernier Annie , Lebel Catherine , El-Jalbout Ramy , Lupien Sonia , de Beaumont Louis , Dehaes Mathieu , Cohen Daniel , McLellan-Lamarche Stephanie , Langevin Lisa Marie , Mazza Joanna , Aungst Taylour 
Published: March 2024

ImportanceResearch on postconcussive symptoms (PCS) following early childhood concussion has been hindered by a lack of measures suitable for this age group, resulting in a limited understanding of their evolution in young children.ObjectiveTo document PCS in the first 3 months after early childhood concussion using a developmentally appropriate measure.Design, Setting, and ParticipantsThis cohort study used data collected at 3 Canadian and 1 US urban pediatric emergency departments (EDs) and 8 Canadian daycares from December 2018 to December 2022 as part of the Kids’ Outcomes and Long-Term Abilities (KOALA) project, a prospective, multicenter, longitudinal cohort study. Participants included children aged 6 to 72 months with early childhood concussion or orthopedic injury (OI) or uninjured children from the community to serve as controls. Data were analyzed from March 2023 to January 2024.ExposureConcussion sustained between ages 6 and 72 months.Main Outcomes and MeasuresPrimary outcomes were cognitive, physical, behavioral and total PCS assessed prior to injury (retrospectively), acutely (within 48 hours), and at 10 days, 1 month, and 3 months after injury or recruitment through caregiver observations using the Report of Early Childhood Traumatic Injury Observations &amp;amp; Symptoms inventory. Group comparisons were analyzed using ordinal regression models.ResultsThe study included 303 children (mean [SD] age, 35.8 [20.2] months; 152 [50.2%] male). Of these, 174 children had a concussion (mean [SD] age,  33.3 [19.9] months), 60 children had an OI (mean [SD] age, 38.4 [19.8] months) and 69 children were uninjured controls (mean [SD] age, 39.7 [20.8] months). No meaningful differences were found between the concussion and comparison groups in retrospective preinjury PCS. Significant group differences were found for total PCS at the initial ED visit (concussion vs OI: odds ratio [OR], 4.33 [95% CI, 2.44-7.69]; concussion vs control: OR, 7.28 [95% CI, 3.80-13.93]), 10 days (concussion vs OI: OR, 4.44 [95% CI, 2.17-9.06]; concussion vs control: OR, 5.94 [95% CI, 3.22-10.94]), 1 month (concussion vs OI: OR, 2.70 [95% CI, 1.56-4.68]; concussion vs control: OR, 4.32 [95% CI, 2.36-7.92]), and 3 months (concussion vs OI: OR, 2.61 [95% CI, 1.30-5.25]; concussion vs control: OR, 2.40 [95% CI, 1.36-4.24]). Significant group differences were also found for domain-level scores (cognitive, physical, behavioral) at various time points.Conclusions and RelevanceIn this early childhood cohort study, concussion was associated with more PCS than OIs or typical development up to 3 months after injury. Given the limited verbal and cognitive abilities typical of early childhood, using developmentally appropriate manifestations and behaviors is a valuable way of tracking PCS and could aid in concussion diagnosis in young children.