Blood alcohol levels may have a specific dose-dependent effect on treatment outcomes for people with traumatic brain injury. This effect is significant at an intermediate blood alcohol level even when multiple variables are taken into account, according to a new study presented this week at the Association of Academic Physiatrists Annual Meeting in Puerto Rico.
What effect does blood alcohol level have on the outcomes of patients with traumatic brain injury (TBI) admitted for rehab? To find out, researchers at the University of Alabama Birmingham examined TBI Model Systems demographic data and conducted a retrospective chart review for acute admission blood alcohol levels for patients in a rehabilitation hospital.
“There have been multiple studies showing a seemingly neuroprotective effect of alcohol on outcomes related to TBI, specifically at six months,” said Nicole Eno, the study’s co-author. “The reason for this research was to explore the validity of those outcomes. To leave the statement open that alcohol can be neuroprotective can be dangerous if taken at face value, which is why we thought it was important to explore this relationship further. It is important to know the effect of alcohol on TBI, because alcohol has a significant relationship with motor vehicle accidents and motor vehicle accidents are the third leading cause of TBI-related emergency department visits, hospitalizations and deaths as of 2013, per the CDC’s [Centers for Disease Control and Prevention] reports.”
The study included 360 people. There were 96 females whose ages ranged from 18 to 84, with an average age of 38.52, and 264 males whose ages ranged from 18 to 80, with an average age of 39.32. Participants in the study were patients who received rehab care for TBI from 2010 to 2017. They were categorized by blood alcohol levels (BAL) at admission to the facility: either none, low (blood alcohol level 1-99 mg/dL), intermediate (BAL 100-199 mg/dL) or high (BAL ≥200 mg/dL). The study’s main outcome measure was the Glasgow Outcome Scale-Extended (GOSE) score at one year, adjusted for potentially confounding factors like age, sex, level of education, pre-injury alcohol use and TBI severity.
The researchers compared patient outcomes across the blood alcohol levels. They used patients with an alcohol level of none as the reference group. They found that the odds ratio of having a moderate or good outcome versus a poor outcome for TBI patients for intermediate alcohol levels was 2.40, compared to the control group, which had no blood alcohol present. Concerning the low and high alcohol levels, they were found to have slightly worse outcomes but were not statistically significant. All data was true even when they adjusted their model to account for age, sex, education level, pre-injury alcohol use and TBI severity.
The study’s findings suggest that there is a significant positive effect on the outcome for patients with intermediate blood alcohol level during admission compared to those with none. This relationship remained significant when multiple variables related to TBI outcomes were included in the analysis. Follow-up study on a larger patient population is necessary to better understand this observed effect of alcohol on outcome, the study’s co-authors said.
“The relationship between alcohol and TBI outcomes is not just a net-neuroprotective effect,” said Ms. Eno. “There is more to be investigated on the relationship between alcohol and TBI before it can be labeled as such. While this study found positive outcomes within a specific blood alcohol range, the fact that the positive effect is not seen at higher or lower levels indicates that more or less alcohol does not mean a better effect.”