A substantial number of patients (30% to 50%) sustains a mild traumatic brain injury (mTBI) while they are under the influence of alcohol. An acute alcohol intoxication (AAI) at the time of injury has been subject of research in severe TBI, but little is known about the relation between AAI and mTBI. This study aimed to describe the characteristics of this intoxicated subgroup and evaluate recovery and outcome in comparison to sober mTBI patients. We included 528 mTBI patients (Glasgow Coma Scale [GCS] score 13-15) admitted to two Level 1 trauma centers as part of a prospective follow-up study. We compared clinical characteristics, demographics, and injury mechanism between groups. Post-concussive complaints, mood disorders, and post-traumatic stress-related complaints were assessed at 2 weeks post-injury, and outcome at 6 months with the Glasgow Outcome Scale Extended (GOSE). Thirty-three percent of the mTBI patients were intoxicated. Results showed that the intoxicated group was younger (36 vs. 40 years; p = 0.001) and were more frequently of male gender (78% vs. 60%; p < .001). The groups also differed in injury related characteristics, with intoxicated patients more frequently sustaining falls or violence-related injuries. The intoxicated group was assessed with a lower GCS score and had a higher hospital admission rate. However, at 2 weeks post-injury, intoxicated patients reported less complaints than the non-alcohol group and showed a better recovery at 6 months (average GOSE scores 7 vs. 7.3; p = 0.030). We conclude that AAI in mTBI represents a characteristically different group, which has implications for prevention measures, as well as the course of recovery.
Keywords: alcohol; complaints; mild traumatic brain injury; outcome; recovery.