Concussion Subtype Identification With the Rivermead Post-concussion Symptoms Questionnaire

Abstract

Classifying concussion in key subtypes according to presenting symptomatology at an early post-injury stage is an emerging approach that may allow prediction of clinical trajectories and delivery of targeted treatments. The Rivermead Post-concussion Symptoms Questionnaire (RPQ) is a simple, freely available, and widely used tool for assessment of the presence and severity of various post-concussion symptoms. We aimed to probe the prevalence among athletes of symptom classes associated with identified concussion phenotypes using the RPQ at baseline and acutely after a concussion. Participants of organized sports aged 12-30 years were baseline-assessed with the expectation that some would experience a concussion during the study period. Concussed athletes were re-assessed within 2 weeks of their injuries. The RPQ was supplemented with three specific questions and reworded for baseline assessment. A binomial test was used to contrast the prevalence of an attribute in the concussed cohort against the probability established by the baseline observation. Three thousand and eighty-eight athletes were baseline-assessed and eighty-nine were re-assessed post-concussion. All concussed athletes endorsed having some elevated symptoms in the RPQ, and such endorsements were more prevalent than those among normal athletes. Moderate-to-severe post-concussion symptoms of specific classes tended to be endorsed with few additional symptoms of other classes of similar intensities. Elevated symptoms detected with the RPQ within as short as 2 weeks after a concussion may help delineate patients' clinical subtypes and guide their treatment. Further refinement of symptom questionnaires and use of objective measures will be needed to properly populate the concussion subtype classification.

Keywords: cognitive; epidemiology; fatigue; migraine; mild traumatic brain injury (mTBI); sleep; vestibular.

Figure 1

Prevalences of six classes of symptoms expressed as cumulative distributions. Open circles and filled squares indicate baseline and post-concussion findings, respectively. An asterisk indicates a statistically significant (p < 0.05) deviation of a post-concussion prevalence from the baseline-derived probability as determined by a binomial test. Also see Table 1.

Figure 2

Overlaps in post-concussion profile characteristics identified with severe symptoms. Eighteen of 89 concussed subjects reported having a severe post-concussion symptom. The distribution of these 18 subjects among the various combinations of presences and absences of endorsement of the five symptom classes is shown as percentages in the Venn diagram with areas of overlap among the five pear-shaped regions.

Figure 3

Overlaps in post-concussion profile characteristics identified with at-least-moderate symptoms. Fifty-seven of 89 concussed subjects reported having an at-least moderate post-concussion symptom. The distribution of these 57 subjects among the various combinations of presences and absences of endorsement of the five symptom classes is shown as percentages in the Venn diagram.

Figure 4

Overlaps in post-concussion profile characteristics identified with at-least mild symptoms. All 89 concussed subjects reported having an at-least mild post-concussion symptom. The distribution of these 89 subjects among the various combinations of presences and absences of endorsement of the five symptom classes is shown as percentages in the Venn diagram.