Persistent impairment based symptoms post mild traumatic brain injury: Does a standard symptom scale detect them?

Aim: To further explore symptoms in patients beyond the expected recovery period post mild Traumatic Brain Injury (mTBI) that are potentially indicative of impairment.

Methods: Ninety-four individuals (62 diagnosed with mTBI within the previous 4-24 weeks and 32 healthy controls) participated in the study. Participants in the mTBI group were further grouped as symptomatic (n = 33) or asymptomatic (n = 29) based on their spontaneous report of symptoms at the time of screening. Measures included a demographic questionnaire, 8 impairment specific self-report clinical tools, and a standard post-mTBI self-report symptom scale (Head Injury Scale (HIS)).

Results: Compared to the control group, scores for all instruments (including the HIS) were higher in the symptomatic mTBI group (P < 0.05), and higher for the neck disability and hyperarousal measures in the asymptomatic mTBI group (p < 0.035), but not the HIS (p > 0.093). Overall 94% of the symptomatic and 62% of the asymptomatic participants post-mTBI, recorded scores considered to be clinically relevant on at least one impairment screening tool. In contrast, only 28% of the asymptomatic mTBI group recorded a clinically relevant score for the HIS.

Conclusion: Symptoms indicative of persisting impairments beyond the expected recovery period were apparent in a substantial proportion of individuals post mTBI. Furthermore, a high percentage of individuals initially reporting as symptom free demonstrated clinically relevant scores on at least one impairment screening tool. Findings also suggest that a standard post-mTBI self-report symptom scale may often not detect the presence of persisting symptoms.