Department of Epidemiology and Public Health, School of Medicine, University of Maryland, Baltimore, Maryland.
Department of Public Health Sciences, Loyola University, Chicago, Illinois.
Am J Epidemiol. 2018 Feb 1;187(2):233-241. doi: 10.1093/aje/kwx254.
Although alcohol exposure results in reduced mortality after traumatic brain injury (TBI) in animal models, clinical trials based on proposed mechanisms have been disappointing and have reported conflicting results. Methodological issues common to many of these clinical studies may have contributed to the spurious results. Our objective was to evaluate the association between blood alcohol concentration (BAC) and in-hospital mortality after TBI, and overcome methodological problems of prior studies. We conducted a retrospective cohort study on individuals treated for isolated TBI (n = 1,084) at the R Adams Cowley Shock Trauma Center (Baltimore, Maryland) from 1997 to 2012. We excluded individuals with injury to other body regions and examined multiple cutpoints of BAC. Our primary outcome was in-hospital mortality. In adjusted logistic regression models, the upper level of each blood alcohol categorization from 0.10 g/dL (odds ratio = 0.63, 95% confidence interval: 0.40, 0.97) through 0.30 g/dL (odds ratio = 0.25, 95% confidence interval: 0.08, 0.84) was associated with reduced risk of mortality after TBI compared with individuals with undetectable BAC. In sensitivity analyses among individuals without penetrating brain injuries (95% firearm-related) (n = 899), the protective association was eliminated. This study provides evidence that the observed protective association between BAC and in-hospital mortality after TBI resulted from bias introduced by inclusion of penetrating injuries.
尽管动物模型研究表明，酒精暴露可降低创伤性脑损伤（TBI）后的死亡率，但基于所提出的机制的临床试验结果令人失望，且报告的结果相互矛盾。这些临床试验中许多常见的方法学问题可能导致了虚假结果。我们的目的是评估 TBI 后血液酒精浓度（BAC）与住院死亡率之间的关系，并克服先前研究中的方法学问题。我们对 1997 年至 2012 年在马里兰州巴尔的摩的 R.亚当斯·考利休克创伤中心（R. Adams Cowley Shock Trauma Center）接受单独 TBI 治疗的个体（n=1084）进行了回顾性队列研究。我们排除了其他身体部位受伤的个体，并检查了多个 BAC 切点。我们的主要结局是住院死亡率。在调整后的逻辑回归模型中，与 BAC 未检出的个体相比，从 0.10 g/dL（比值比=0.63，95%置信区间：0.40，0.97）到 0.30 g/dL（比值比=0.25，95%置信区间：0.08，0.84）的每个血液酒精分类的上限水平均与 TBI 后死亡率降低相关。在没有穿透性脑损伤（95%与枪支相关）的个体（n=899）的敏感性分析中，这种保护相关性消失了。本研究提供的证据表明，BAC 与 TBI 后住院死亡率之间观察到的保护相关性是由于纳入穿透性损伤引起的偏倚所致。
