Risk of Repeat Concussion Among Patients Diagnosed at a Pediatric Care Network.

Objective: To quantify the risk of repeat concussions for children and identify demographic and clinical aspects of the index concussion associated with repeat injury.

Study Design: For this retrospective cohort study, we queried the Children's Hospital of Philadelphia healthcare network's unified electronic health record to identify all 5- to 15-year-old patients who had their first clinical visit for an index concussion at a Children's Hospital of Philadelphia location from July 2012 through June 2013. A 25% random sample (n = 536) were selected. Clinical data were abstracted for their index concussion and all concussion-related visits for 2 years following the index concussion.

Results: Overall, 16.2% (n = 87) of patients experienced at least 1 repeat concussion within 2 years of their index concussion. The risk of repeat concussion increased with patient age (9.5% for ages 5-8 years; 10.7% for ages 9-11 years; and 19.8% for ages 12-15 years). After we adjusted for other factors, risk was particularly heightened among patients whose index concussion had a longer clinical course (>30 vs 0-7 days, adjusted risk ratio 1.65 [1.01-2.69]) and greater symptom burden (>11 vs 0-2 symptoms, adjusted risk ratio 2.12 [1.12-3.72]).

Conclusions: We estimate that 1 in 6 youth diagnosed with a concussion are diagnosed with a subsequent concussion within 2 years and that several clinical characteristics of the index concussion increase this risk. Identifying factors associated with a repeat injury is essential to inform the clinical management of concussion and direct injury prevention efforts.