Statement of purpose: This archival study sought to clarify the relationship between admission blood alcohol level (BAL) after traumatic brain injury (TBI) and subsequent neuropsychological functioning. It was hypothesized that BAL would be positively correlated with impairment on basic neuropsychological tests and that this relation would weaken as time since TBI increased.
Methods: Fifty-eight patients were tested within 60 days of their TBI. Correlational analyses were used to test the relation between neuropsychological performance and admission BAL.
Results: As expected, BAL was unrelated to demographic variables or lag time between TBI and time of testing, Bivariate correlations showed that higher BAL predicted poorer performance on a broad range of neuropsychological tests. Patients tested less than 30 days after their TBI showed the strongest effects.
Conclusions: Neuropsychological impairments detected 1-2 months after TBI may be affected by BAL at the time of hospital admission. The influence of BAL seems greatest during the first month post-injury, but may persist beyond 30 days in some areas of cognitive function. Blood alcohol at the time of injury may have a direct effect on cognitive functioning or may be a proxy for the effects of chronic alcohol use or abuse. Clinical implications are discussed.