Identifying Children and Adolescents at Risk for Persistent Postconcussion Symptoms

It isestimated thatmorethan630000childrenandadolescents present toemergencydepartments (EDs)eachyear intheUnited Statesaftersustainingatraumaticbraininjury(TBI),withthevast majority of these categorized asmildTBI,alsocommonlyreferredtoasconcussion.1,2This is likely a significantunderestimationof the true burdenofmildTBI becausemanypatients may seek care innonemergency settings (such asphysicianoffices) and are not routinely captured in systematic databases, whereas other patientswithmild TBImay be evaluated on the sidelinesofathleticeventsbynonphysiciansorneverseekcare. In a consensus statement of the International Conference on Concussion in Sport,3 mild TBI or concussion was defined as “a complex pathophysiological process affecting the brain, induced by biomechanical forces caused either by a direct blow to the head, face, neck or elsewhere on the bodywith an ‘impulsive’ force transmitted to thehead” resulting in a “rapid onset of short-lived impairment of neurological function” that largely reflects a “functional disturbance rather than a structural injury and, as such, no abnormality is seen on standard structural neuroimaging studies.” Most individuals usually recover rapidly after mild TBI.4 However, according to Eisenberg et al4 and as reported by Zemek and colleagues5 in this issue of JAMA, approximately one-third of children and adolescents with mild TBI will experience diverse patterns of physical, cognitive, or emotional symptoms beyond 1 month after injury that can affect every day functioning and quality of life. In the immediate management of patients with TBI, the clinician’s initial responsibilities include assessing the extent and severity of symptoms and signs, evaluating the patient for structural intracranial injury, treatingsymptoms,andarranging follow-upcare.Priorresearchprovidesinformationregardingthe identificationofpatientswhoarenot likely tohaveclinically importantTBIsanddonotrequireneuroimaging.6Despite increasing researchandattentiongiven toTBI, evidenceaboutpostinjurymanagement is limited and consequently patients, family members,andhealthcareprofessionalsareuncertainabout trajectories of symptoms and effective interventions. Risk factors have been identified for persistent postconcussive symptoms (PPCS), such as adolescent age, headache, nausea or vomiting, dizziness, and prior TBI in selected populations,7,8 but a comprehensive, yetpractical, clinical risk score using information readily available at the time of injury, regardlessof themechanism, is lacking. Ideally,a riskscore for PPCS would be useful for assessing clinical prognosis and theneed forpostinjury accommodations and follow-up. In addition, such a risk scoremay help to identify patients at highest risk of prolonged symptoms that will most likely benefit from interventions to facilitate recovery and it could be used to stratify patients in concussion management research. Zemekandcolleagues5 reportaderivedandvalidatedscore tostratify therisk forPPCSamongchildrenandadolescentspresenting to the ED with acute concussion. The risk prediction estimates generatedby this toolwere superior to clinicianprediction of risk for PPCS, which was no better than a coin toss. In theirmultisite (9 pediatric EDs across Canada), prospective observational cohort study of 3063 children and adolescents, aged 5 to 18 years, with 1 or more symptoms associated with concussion andaGlasgowComaScale score of 14or 15, Zemek et al identified9 factors that are easily obtainable fromthehistoryandphysical examination fromapotential pool of46variables thatwerehighlyassociatedwithPPCS.The strongest risk factors were female sex, age of 13 years or older,migraine history, previous concussion with symptoms lasting longer than 1week,headache, sensitivity tonoise, fatigue, answeringquestions slowly, and 4 or more errors on the Balance Error ScoringSystemtandemstance.Theprimarystudyoutcomewasdefined as the patient-reported presence of 3 or more new or worsening symptoms compared with recalled state of being prior to the injury documented on questionnaires administered 28 days postinjury via email or telephone. Among the 3063patients included in the study, 801 (31%) had PPCS, which is comparable with the estimate of 33% for mostpediatric EDs.4The9-factormodelhad fair ability topredict PPCS (area under the curve of 0.71). The authors generated a 12-point scoring regimen and proposed 3 levels of risk for PPCS. In the low-risk category, the probabilities of PPCS ranged from 4.1% to 11.8%. Because these patients would be unlikely to develop PPCS, an emergency clinician could provide some reassurance to thepatient and family about thepatient’s likelihoodof full recovery.High levels of subsequent resourceuse, suchas referral toaspecialtyclinic, generallywould not be necessary for these individuals. In the high-risk category, theprobabilityofPPCSrangedfrom57.1%to80.8%,suggesting that these patients might benefit from close followup, anticipatory guidance about expected symptom recovery trajectory, activity modifications and school accommodations, and referral to specialty care. In the medium risk category, the probabilities of PPCS ranged from 16.4% to 47.6%. This is not much of a change from the pretest probability of 33%, and froma clinical point of view, this range of risk scores maynot be lowenough to be reassuring or high enough to deRelated article page 1014 Opinion