Alcohol and Risk of Mortality in Patients With Traumatic Brain Injury

Fast Maturation of Splenic Dendritic Cells Upon TBI Is Associated With FLT3/FLT3L Signaling

The consequences of systemic inflammation are a significant burden after traumatic brain injury (TBI), with almost all organs affected. This response consists of inflammation and concurrent immunosuppression after injury. One of the main immune regulatory organs, the spleen, is highly interactive with the brain. Along this brain–spleen axis, both nerve fibers as well as brain-derived circulating mediators have been shown to interact directly with splenic immune cells. One of the most significant comorbidities in TBI is acute ethanol intoxication (EI), with almost 40% of patients showing a positive blood alcohol level (BAL) upon injury. EI by itself has been shown to reduce proinflammatory mediators dose-dependently and enhance anti-inflammatory mediators in the spleen. However, how the splenic immune modulatory effect reacts to EI in TBI remains unclear. Therefore, we investigated early splenic immune responses after TBI with and without EI, using gene expression screening of cytokines and chemokines and fluorescence staining of thin spleen sections to investigate cellular mechanisms in immune cells. We found a strong FLT3/FLT3L induction 3 h after TBI, which was enhanced by EI. The FLT3L induction resulted in phosphorylation of FLT3 in CD11c+ dendritic cells, which enhanced protein synthesis, maturation process, and the immunity of dendritic cells, shown by pS6, peIF2A, MHC-II, LAMP1, and CD68 by immunostaining and TNF-α expression by in-situ hybridization. In conclusion, these data indicate that TBI induces a fast maturation and immunity of dendritic cells which is associated with FLT3/FLT3L signaling and which is enhanced by EI prior to TBI.

Alcohol is not associated with increased mortality in adolescent traumatic brain injury patients

PURPOSE

Compared to adults, there is a paucity of data regarding the association of a positive alcohol screen (PAS) and outcomes in adolescent patients with traumatic brain injury (TBI). We hypothesize adolescent TBI patients with a PAS on admission to have increased mortality compared to patients with a negative alcohol screen.

METHODS

The 2017 Trauma Quality Improvement Program database was queried for patients aged 13-17 years presenting with a TBI and serum alcohol screen. Patients with missing information regarding midline shift on imaging and Glasgow Coma Scale (GCS) score were excluded. A multivariable logistic regression analysis for mortality was performed.

RESULTS

From 2553 adolescent TBI patients with an alcohol screen, 220 (8.6%) had a PAS. Median injury severity scores and rates of penetrating trauma (all p > 0.05) were similar between alcohol positive and negative patients. Patients with a PAS had a similar mortality rate (13.2% vs. 12.1%, p = 0.64) compared to patients with a negative screen. Multivariate logistic regression controlling for risk factors associated with mortality revealed a PAS to confer a similar risk of mortality compared to alcohol negative patients (p = 0.40).

CONCLUSION

Adolescent TBI patients with a PAS had similar associated risk of mortality compared to patients with a negative alcohol screen.

Differential effect of ethanol intoxication on peripheral markers of cerebral injury in murine blunt traumatic brain injury

Background

Blood-based biomarkers have proven to be a reliable measure of the severity and outcome of traumatic brain injury (TBI) in both murine models and patients. In particular, neuron-specific enolase (NSE), neurofilament light (NFL) and S100 beta (S100B) have been investigated in the clinical setting post-injury. Ethanol intoxication (EI) remains a significant comorbidity in TBI, with 30–40% of patients having a positive blood alcohol concentration post-TBI. The effect of ethanol on blood-based biomarkers for the prognosis and diagnosis of TBI remains unclear. In this study, we investigated the effect of EI on NSE, NFL and S100B and their correlation with blood–brain barrier integrity in a murine model of TBI.

Methods

We used ultra-sensitive single-molecule array technology and enzyme-linked immunosorbent assay methods to measure NFL, NSE, S100B and claudin-5 concentrations in plasma 3 hours post-TBI.

Results

We showed that NFL, NSE and S100B were increased at 3 hours post-TBI. Interestingly, ethanol blood concentrations showed an inverse correlation with NSE but not with NFL or S100B. Claudin-5 levels were increased post-injury but no difference was detected compared to ethanol pretreatment. The increase in claudin-5 post-TBI was correlated with NFL but not with NSE or S100B.

Conclusions

Ethanol induces an effect on biomarker release in the bloodstream that is different from TBI not influenced by alcohol. This could be the basis of investigations into humans.

The role of alcohol and other drugs on emergency department traumatic injury mortality in the United States

BACKGROUND

Alcohol and other drugs (AOD) increase the risk of traumatic injury occurring, but data suggest a protective benefit in preventing trauma-related mortality. The objective of this study is to describe the epidemiology of AOD-related traumatic injury in the US over a recent 7 year period and assess the interaction of traumatic injury and AOD on pre-admission fatality on both an additive scale using incidence contrasts and on a statistical multiplicative scale using survey-adjusted logistic regression.

METHODS

Using the National Emergency Department Sample (NEDS), we describe the epidemiology of alcohol and substance-related emergency department traumatic injury over a recent period. AOD-related injury was assessed using survey-adjusted counts and means. Ratio estimates and differences were calculated using simulations based on survey-adjusted counts and standard errors. Differences in trends over time were evaluated by comparing the slopes of linear regression equations with year as the predictor variable.

RESULTS

Alcohol and substance-related emergency department injury discharges increased 9.8 % during the study period. There was a statistically significant interaction between traumatic injury death and AOD on both an additive scale and multiplicative scale. (Odds Ratio for interaction term = 1.76, 95 % CI = 1.53, 2.03).

CONCLUSIONS

AOD use does not provide a protective benefit in the setting of trauma, but rather is an important contributor to traumatic injury mortality.

Sex, Drugs, and TBI: The Role of Sex in Substance Abuse Related to Traumatic Brain Injuries

Traumatic brain injuries (TBI) are a significant public health problem costing billions of dollars in healthcare costs and lost productivity while simultaneously reducing the quality of life for both patients and caregivers. Substance abuse is closely interconnected with TBI, as intoxicated individuals are at a greater risk of suffering brain injuries, and TBI may serve as a risk factor for the subsequent development of substance use disorders. There are also prominent sex differences in the etiology, epidemiology, and consequences of TBI. For instance, men are more likely to be injured on sporting fields or in auto accidents, while women are disproportionately likely to suffer TBI associated with intimate partner violence. Moreover, while men are much more likely to suffer TBI during late adolescence–young adulthood, sex differences in the incidence of TBI are much less prominent during other developmental epochs. Further, there are prominent sex differences in substance abuse biology; for example, while more men meet diagnostic criteria for substance abuse disorders, women tend to advance from casual use to addiction more quickly. In this paper, we will discuss the emerging clinical and preclinical evidence that these sex differences in TBI and substance abuse interact and may be prominent determinates of long-term outcomes.

Traumatic brain injury and alcohol intoxication: effects on injury patterns and short-term outcome

Purpose

A significant number of patients with traumatic brain injuries (TBI) are diagnosed with elevated blood alcohol concentration (BAC). Recent literature suggests a neuroprotective effect of alcohol on TBI, possibly associated with less morbidity and mortality. Our goal is to analyze the association of different levels of BAC with TBI characteristics and outcome.

Methods

Adult patients with moderate to severe TBI (AIS ≥ 2) and measured BAC admitted to the Trauma Centre West (TCW), during the period 2010–2015, were retrospectively analyzed. Data included injury severity (AIS), length of hospitalization, admittance to the Intensive Care Unit (ICU) and in-hospital mortality. The association of BAC with ICU admittance and in-hospital mortality was analyzed using multivariable logistic regression analysis with correction for potentially confounding variables.

Results

BACs were available in 2,686 patients of whom 42% had high, 26% moderate, 6% low and 26% had normal levels. Patients with high BAC’s were predominantly male, were younger, had lower ISS scores, lower AIS-head scores and less concomitant injuries compared to patients in the other BAC subgroups. High BACs were associated with a lower risk for in-hospital mortality (AOR 0.36, 95% CI 0.14–0.97). Also, patients with moderate and high BACs were less often admitted to the ICU (respectively, AOR 0.36, 95% CI 0.25–0.52 and AOR 0.40, 95% CI 0.29–0.57).

Conclusion

The current study suggests that in patients with moderate to severe TBI, increasing BACs are associated with less severe TBI, less ICU admissions and a higher survival. Further research into the pathophysiological mechanism is necessary to help explain these findings.

Comorbidity in adults with traumatic brain injury and all-cause mortality: a systematic review

OBJECTIVES

Comorbidity in traumatic brain injury (TBI) has been recognised to alter the clinical course of patients and influence short-term and long-term outcomes. We synthesised the evidence on the effects of different comorbid conditions on early and late mortality post-TBI in order to (1) examine the relationship between comorbid condition(s) and all-cause mortality in TBI and (2) determine the influence of sociodemographic and clinical characteristics of patients with a TBI at baseline on all-cause mortality.

DESIGN

Systematic review.

DATA SOURCES

Medline, Central, Embase, PsycINFO and bibliographies of identified articles were searched from May 1997 to January 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Included studies met the following criteria: (1) focused on comorbidity as it related to our outcome of interest in adults (ie, ≥18 years of age) diagnosed with a TBI; (2) comorbidity was detected by any means excluding self-report; (3) reported the proportion of participants without comorbidity and (4) followed participants for any period of time.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted the data and assessed risk of bias using the Quality in Prognosis Studies tool. Data were synthesised through tabulation and qualitative description.

RESULTS

A total of 27 cohort studies were included. Among the wide range of individual comorbid conditions studied, only low blood pressure was a consistent predictors of post-TBI mortality. Other consistent predictors were traditional sociodemographic risk factors. Higher comorbidity scale, scores and the number of comorbid conditions were not consistently associated with post-TBI mortality.

CONCLUSIONS

Given the high number of comorbid conditions that were examined by the single studies, research is required to further substantiate the evidence and address conflicting findings. Finally, an enhanced set of comorbidity measures that are suited for the TBI population will allow for better risk stratification to guide TBI management and treatment.

PROSPERO REGISTRATION NUMBER

CRD42017070033.

Effects of ethyl alcohol on injuries severity according to injury severity scales in pedestrian fatal injury in traffic crashes

INTRODUCTION

The dominant cause of injuries in traffic crashes. A significant portion of them affects victims under the influence of ethyl alcohol. The goal of the studies was to assess the correlation between the state of sobriety and the severity of injuries expressed by injury severity scales in fatal pedestrian victims of traffic crashes. Research Material and Method: The data were obtained from the Warsaw Medical University's Department of Forensic Medicine. The analysis covered the data for 2009-2013 and included 200 fatal pedestrian victims hit by passenger cars. The assessment of the effect of risk factors on injury severity expressed in terms of injury severity scales such as Life Threat Indicator (LTI), International Classification based Injury Severity Score (ICISS), Injury Severity Score (ISS) and New Injury Severity Score (NISS), was made using adequately selected methods of statistical analysis.

RESULTS

As alcohol concentration increases in women, the values of LTI, ICISS-10 and ICISS-15 decrease, which denotes more severe injuries. In the ISS and NISS, the effect of alcohol concentration on the severity of injuries turned out to be negligible. However, these injuries are significantly heavier in women than in men. According to all the scales used, the older the victims, the milder injuries cause their death.

CONCLUSIONS

The studies show that ethyl alcohol concentration may harm injury severity, especially in the case of women. The assessment of the severity of injuries in traffic crash victims is significantly influenced by their age and gender. The more risk factors the scale takes into consideration, the more precise is the assessment.

Alcohol in Traumatic Brain Injury: Toxic or Therapeutic?

BACKGROUND

Alcohol (EtOH) poses a challenge in traumatic brain injuries (TBIs) given its metabolic and neurologic impact. Studies have had opposing results regarding mortality and complication rates in the intoxicated TBI patient. We hypothesized that trauma mechanism, brain injury severity, and blood alcohol concentration (BAC) would influence the impact of EtOH on mortality in TBI.

METHODS

We performed a single-institution retrospective review of consecutive adult trauma patients tested for EtOH and a diagnosis of TBI. The primary outcome was mortality, and secondary outcomes included infectious complications. The primary analysis included univariate and multivariate regression comparing mortality between intoxicated and sober patients, at different values of BAC, different brain injury severities, and among mechanisms of trauma.

RESULTS

Admission EtOH was assessed in 583 patients with TBI, with 256 testing positive for EtOH and 327 testing negative. Overall, EtOH was associated with lower mortality on univariate analysis (4.7% versus 8.9%, P = 0.05) but not on multivariate analysis (P = 0.21). There was no effect of EtOH on mortality when patients were stratified by brain injury severity or among penetrating trauma victims. However, EtOH was associated with lower overall infectious complications on univariate and multivariate regression. Finally, EtOH was predictive of mortality with an area under the receiver operator characteristic curve of 0.83.

CONCLUSIONS

We found that EtOH is not associated with mortality in the patient with TBI, suggesting no causative effect. However, EtOH showed some predictability of mortality based on a receiver operator characteristic analysis. Interestingly, EtOH was associated with lower infectious complications, suggesting an immunomodulatory effect of EtOH in TBI.

Association of Alcohol With Mortality After Traumatic Brain Injury

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.

Blood Ethanol Levels Are Not Related to Coagulation Changes, as Measured by Thromboelastography, in Traumatic Brain Injury Patients

BACKGROUND

Brain injury is a leading cause of death and disability in trauma patients. Ethanol (EtOH) use near the time of injury may contribute to worse outcomes in these patients by exacerbating coagulopathy. There are limited data regarding the effects of EtOH on coagulation and progression of traumatic intracranial hemorrhage (TICH).

METHODS

We performed a retrospective analysis of a prospective observational study of 168 trauma patients with TBI at an urban level 1 trauma center. Thromboelastography (TEG) was performed on admission and over the subsequent 48 hours. Demographic, physiologic, and outcomes data were collected. Computed tomography imaging of the head performed within the first 48 hours of admission was analyzed for progression of TICH.

RESULTS

Thirty-six percent of patients (n = 61) had positive blood EtOH on admission (median EtOH level = 198 mg/dL [range, 16-376 mg/dL]). EtOH-positive patients were less severely injured than EtOH-negative patients (P = 0.01). Other admission demographic and physiologic variables were similar between groups. There were no significant differences in TEG values between EtOH-positive and EtOH-negative patients on admission or during the subsequent 48 hours. There were no differences in radiographic progression of hemorrhage, the need for neurosurgical procedure, or mortality between EtOH-positive and EtOH-negative patients.

CONCLUSIONS

EtOH use near the time of traumatic injury was not associated with alterations in coagulation, as measured by traditional coagulation tests or by TEG, in patients with TICH. Furthermore, a positive blood alcohol at admission was not associated with increased mortality or need for neurosurgical procedure these patients.

Cut-Point Levels of Phosphatidylethanol to Identify Alcohol Misuse in a Mixed Cohort Including Critically Ill Patients

BACKGROUND

Although alcohol misuse is associated with deleterious outcomes in critically ill patients, its detection by either self-report or examination of biomarkers is difficult to obtain consistently. Phosphatidylethanol (PEth) is a direct alcohol biomarker that can characterize alcohol consumption patterns; however, its diagnostic accuracy in identifying misuse in critically ill patients is unknown.

METHODS

PEth values were obtained in a mixed cohort comprising 122 individuals from medical and burn intensive care units (n = 33), alcohol detoxification unit (n = 51), and healthy volunteers (n = 38). Any alcohol misuse and severe misuse were referenced by Alcohol Use Disorders Identification Test (AUDIT) and AUDIT-C scores separately. Mixed-effects logistic regression analysis was performed, and the discrimination of PEth was evaluated using the area under the receiver-operating characteristic (ROC) curve.

RESULTS

The area under the ROC curve for PEth was 0.927 (95% CI: 0.877, 0.977) for any misuse and 0.906 (95% CI: 0.850, 0.962) for severe misuse defined by AUDIT. By AUDIT-C, the area under the ROC curves was 0.948 (95% CI: 0.910, 0.956) for any misuse and 0.913 (95% CI: 0.856, 0.971) for severe misuse. The PEth cut-points of ≥250 and ≥400 ng/ml provided optimal discrimination for any misuse and severe misuse, respectively. The positive predictive value for ≥250 ng/ml was 88.7% (95% CI: 77.5, 95.0), and the negative predictive value was 86.7% (95% CI: 74.9, 93.7). PEth ≥ 400 ng/ml achieved similar values, and similar results were shown for AUDIT-C. In a subgroup analysis of critically ill patients only, test characteristics were similar to the mixed cohort.

CONCLUSIONS

PEth is a strong predictor and has good discrimination for any and severe alcohol misuse in a mixed cohort that includes critically ill patients. Cut-points at 250 ng/ml for any, and 400 ng/ml for severe, are favorable. External validation will be required to establish these cut-points in critically ill patients.

Acute Alcohol Exposure and Risk of Mortality of Patients with Traumatic Brain Injury: A Systematic Review and Meta-Analysis

After traumatic brain injury (TBI), patients usually live with significant disability and socioeconomic burdens. Acute exposure to alcohol is considered a major risk factor for TBI. Numerous studies have examined whether alcohol exposure is related to the risk of mortality in patients with TBI, yet the results remain inconsistent. We performed a meta-analysis to assess whether acute alcohol exposure affects the mortality rate of TBI patients. We searched PubMed, EMBASE, and the Cochrane Library up to November 2015 for relevant studies. We screened studies based on their inclusion criteria and selected the studies that reported mortality rate, which included 18 observational studies. We used R to analyze the included data. An initial result showed that the presence of a positive blood alcohol concentration (BAC) had no significant relation with mortality rate (OR = 0.92, 95% CI = 0.83 to 1.01), but there was notable heterogeneity along with variable results according to sensitivity analysis. For the BAC-positive population, low BAC (1 to 100 mg/dl) carried a higher risk of mortality than moderate BAC (100 to 230 mg/dl) (OR = 1.40, 95% CI = 1.09 to 1.81), moderate and high BAC as a single category (>100 mg/dl) (OR = 1.57, 95% CI = 1.28 to 1.94), or high BAC (>230 mg/dl) (OR = 1.76, 95% CI = 1.34 to 2.30). However, moderate BAC did not increase the mortality risk when compared with high BAC (OR = 1.20, 95% CI = 0.89 to 1.63). Whether positive BAC at the time of admission after TBI reduces mortality rate compared with the rate under negative BAC remains unknown. In addition, low BAC (1 to 100 mg/dl) poses a risk of mortality compared with higher BAC. Further studies assessing the effect of alcohol between the BAC-positive group and the BAC-negative group are still needed.

Alcohol and mortality after moderate to severe traumatic brain injury: a meta-analysis of observational studies

OBJECT

Experimental studies have shown numerous neuroprotective properties of alcohol (“ethanol”) after TBI, but clinical studies have provided conflicting results. The authors aimed to assess the relationship between positive blood alcohol concentration (BAC) on hospital admission and mortality after moderate to severe traumatic brain injury (TBI).

METHODS

The authors searched 8 databases for observational studies reported between January 1, 1990, and October 7, 2013, and investigated the effect of BAC on mortality after moderate to severe TBI. Reviews of each study were conducted, and data were extracted according to the MOOSE and PRISMA guidelines. Study quality was assessed using the Newcastle-Ottawa scale. The Mantel-Haenszel fixed effect methodology was used to generate pooled estimates. Heterogeneity was dealt with by multiple sensitivity analyses.

RESULTS

Eleven studies with a total of 95,941 patients (42% BAC positive and 58% BAC negative) were identified for the primary analysis (overall mortality 12%). Primary analysis showed a significantly lower risk of death for BAC-positive patients compared with BAC-negative patients (crude mortality 11.0% vs 12.3%, pooled OR 0.84 [95% CI 0.81–0.88]), although flawed by heterogeneity (I2 = 68%). Multiple sensitivity analyses, including 55,949 and 51,772 patients, yielded similar results to the primary analysis (crude mortality 12.2% vs 14.0%, pooled OR 0.87 [95% CI 0.83–0.92] and crude mortality 8.7% vs 10.7%, pooled OR 0.78 [95% CI 0.74–0.83]) but with good study homogeneity (I2 = 36% and 14%).

CONCLUSIONS

Positive BAC was significantly associated with lower mortality rates in moderate to severe TBI. Whether this observation is due to selection bias or neuroprotective effects of alcohol remains unknown. Future prospective studies adjusting for TBI heterogeneity is advocated to establish the potential favorable effects of alcohol on outcome after TBI.

Alcohol Intake and Reduced Mortality in Patients with Traumatic Brain Injury

BACKGROUND

The purpose of our study was to determine whether alcohol intake influences short-term mortality in patients with traumatic brain injury (TBI), using a comprehensive trauma database.

METHODS

We collected data from 7 emergency departments (EDs) between June 1, 2008 and May 31, 2010, using the same data form. Cases were included if they met the following criteria: (i) older than 15 and (ii) injuries including TBI. Demographics and outcomes were compared between patients with and without alcohol intake. We present the risk of mortality using hazard ratios and 95% confidence intervals.

RESULTS

A total of 76,596 trauma patients visited the EDs during the study period; 12,980 patients were older than 15 and had TBI. There were 4,009 (30.9%) patients in the alcohol-intake group, of whom 3,306 (82.5%) patients were male, 1,450 (36.2%) patients were moved by ambulance, and 1,218 (30.4%) patients' injuries were intentional. The most frequent injury mechanism was falling down with alcohol intake and blunt injury without alcohol intake. Mortality rate was 1.0% with alcohol intake and 2.0% without alcohol intake. After adjusting for all factors related to mortality, the hazard ratio of mortality was 0.72 in the alcohol-intake group.

CONCLUSIONS

Mortality rate due to TBI in the alcohol-intake group appears to be lower compared to that in the no-alcohol-intake group after adjusting for main confounding variables.

Acute Alcohol Use and Injury Patterns in Young Adult Prehospital Patients

The objective was to determine if acute alcohol consumption is associated with differences in injury pattern among young adult patients with traumatic injuries presenting to emergency medical services (EMS). A cross-sectional, retrospective review of prehospital patient care reports (PCRs) was conducted evaluating injured patients who presented to a collegiate EMS agency from January 1, 2011 to December 31, 2012. Included patients were age 18-24 y and sustained an injury within the previous 24 h. PCRs were reviewed independently by two abstractors to determine if the patient was documented to have acutely consumed alcohol proximate to his/her injury. Primary and secondary sites of regional body injury were recorded. Injury severity was recorded using the Revised Trauma Score (RTS). The association between primary injury site and acute alcohol use was assessed using a chi-square test. Multiple logistic regression was used to control for sex in predicting injury type. Of 440 injured patients, 135 (30.6%) had documented alcohol use prior to injury. Acute alcohol consumption altered the overall pattern of regional injury (p < 0.001). Alcohol users were more likely to present with injury secondary to assault, fall/trip, and unknown mechanism of injury (p < 0.001, all comparisons). RTS scores were statistically lower in the alcohol group (p < 0.001), although the clinical significance of this is unclear. Controlling for sex, acute alcohol consumption predicted increased risk of head/neck injury 5.59-fold (p < 0.001). Acute alcohol use in collegiate EMS patients appears to alter injury patterns in young adults and increases risk of head/neck injury. EMS providers in similar agencies should consider these trends when assessing and treating injured college-aged patients.

The Moderation of Blood Alcohol Levels on Higher Odds of Survival among American Indians with Violent, Blunt-Force Traumatic Brain Injuries

This study assessed the moderation of blood alcohol level (BAL) and American Indian race on survival of patients with violent traumatic brain injury (TBI). An initial logistic regression model indicated that those who were American Indian and insured had higher odds of survival and those with higher injury severity scores and low-medium BAL were less likely to survive. A second logistic regression model including a relationship between American Indians and BAL found that American Indians had a higher odds of survival which tripled when they have no BAL. Low-medium and high BAL were associated with less likelihood of survival among White patients.

Alcohol exposure, injury, and death in trauma patients

BACKGROUND

The association of alcohol use with in-hospital trauma deaths remains unclear. This study identifies the association of blood alcohol content (BAC) with in-hospital death accounting for injury severity and mechanism.

METHODS

This study involves a historical cohort of 46,222 admissions to a statewide trauma center between January 1, 2002, and October 31, 2011. Blood alcohol was evaluated as an ordinal variable: 1 mg/dL to 100 mg/dL as moderate blood alcohol, 101 mg/dL to 230 mg/dL as high blood alcohol, and greater than 230 mg/dL as very high blood alcohol.

RESULTS

Blood alcohol was recorded in 44,502 patients (96.3%). Moderate blood alcohol was associated with an increased odds for both penetrating mechanism (odds ratio [OR], 2.22; 95% confidence interval [CI], 2.04-2.42) and severe injury (OR, 1.25; 95% CI, 1.16-1.35). Very high blood alcohol had a decreased odds for penetrating mechanism (OR, 0.75; 95% CI, 0.67-0.85) compared with the undetectable blood alcohol group. An inverse U-shaped association was shown for severe injury and penetrating mechanism by alcohol group (p < 0.001). Moderate blood alcohol had an increased odds for in-hospital death (OR, 1.50; 95% CI, 1.25-1.79), and the odds decreased for very high blood alcohol (OR, 0.69; 95% CI, 0.54-0.87). An inverse U-shaped association was also shown for in-hospital death by alcohol group (p < 0.001). Model discrimination for in-hospital death had an area under the receiver operating characteristic curve of 0.64 (95% CI, 0.63-0.65).

CONCLUSION

Injury severity and mechanism are strong intermediate outcomes between alcohol and death. Severe injury itself carried the greatest odds for death, and with the moderate BAC group at greatest odds for severe injury and the very high BAC group at the lowest odds for severe injury. The result was a similar inverse-U shaped curve for odds for in-hospital death. Clear associations between blood alcohol and in-hospital death cannot be analyzed without consideration for the different injuries by blood alcohol groups.

LEVEL OF EVIDENCE

Epidemiologic study, level III.

Ethanol and isolated traumatic brain injury

The aim of this systematic review was to determine whether ethanol is neuroprotective or associated with adverse effects in the context of traumatic brain injury (TBI). Approximately 30-60% of TBI patients are intoxicated with ethanol at the time of injury. We performed a systematic review of the literature using a combination of keywords for ethanol and TBI. Manuscripts were included if the population studied was human subjects with isolated moderate to severe TBI, acute ethanol intoxication was studied as an exposure variable and mortality reported as an outcome. The included studies were assessed for heterogeneity. A meta-analysis was performed and the pooled odds ratio (OR) for the association between ethanol and in-hospital mortality reported. There were seven studies eligible for analysis. A statistically significant association favouring reduced mortality with ethanol intoxication was found (OR 0.78; 95% confidence interval 0.73-0.83). Heterogeneity among selected studies was not statistically significant (p=0.25). Following isolated moderate-severe TBI, ethanol intoxication was associated with reduced in-hospital mortality. The retrospective nature of the studies, varying definitions of brain injury, degree of intoxication and presence of potential confounders limits our confidence in this conclusion. Further research is recommended to explore the potential use of ethanol as a therapeutic strategy following TBI.

Acute alcohol intoxication and long-term outcome in patients with traumatic brain injury

The effect of blood alcohol concentration (BAC) on outcome after traumatic brain injury (TBI) is controversial. We sought to assess the independent effect of positive BAC on long-term outcome in patients with TBI treated in the intensive care unit (ICU). We performed a retrospective analysis of 405 patients with TBI, admitted to the ICU of a large urban Level 1 trauma center between January 2009 and December 2012. Outcome was six-month mortality and unfavorable neurological outcome (defined as a Glasgow Outcome Scale score of 1 [death], 2, [vegetative state], or 3 [severe disability]). Patients were categorized by admission BAC into: no BAC (0.0‰; n=99), low BAC (<2.3‰; n=140) and high BAC (≥2.3‰; n=166). Logistic regression analysis, adjusting for baseline risk and severity of illness, was used to assess the independent effect of BAC on outcome (using the no BAC group as the reference). Overall six-month mortality was 25% and unfavorable outcome was 46%. Multivariate analysis showed low BAC to independently reduce risk of six-month mortality compared with no BAC (low BAC adjusted odds ratio [AOR] 0.41, 95% confidence interval [CI] 0.19-0.88, p=0.021) and high BAC (AOR 0.58, 95% CI 0.29-1.15, p=0.120). Furthermore, a trend towards reduced risk of six-month unfavorable neurological outcome for patients with positive BAC, compared to patients with negative BAC, was noted, although this did not reach statistical significance (low BAC AOR 0.65, 95% CI 0.34-1.22, p=0.178, and high BAC AOR 0.59, 95% CI 0.32-1.09, p=0.089). In conclusion, low admission BAC (<2.3‰) was found to independently reduce risk of six-month mortality for patients with TBI, and a trend towards improved long-term neurological outcome was found for BAC-positive patients. The role of alcohol as a neuroprotective agent warrants further studies.

Epidemiology of traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of death, and in a recent analysis it was found that nearly one-third of all injury-related deaths in the US have at least one diagnosis of TBI (CDC-Quickstats, 2010). This chapter presents the burden of TBI as regards age group, gender, costs, race, emergency department (ED) visits, hospitalizations, and deaths. Injury trends over a 15 year period are examined. Rehabilitation estimates and disability estimates are also available. Through good epidemiology we can better understand the causes of TBI and design more effective intervention programs to reduce injury. Important sources of evidence for this chapter include mostly studies from the US because of their leading work in the epidemiology of this important injury.

Prevalence and consequences of positive blood alcohol levels among patients injured at work

Aims:

The aim of this study was to characterize positive blood alcohol among patients injured at work, and to compare the severity of injury and outcome of blood alcohol concentration (BAC) positive and negative patients.

Settings and Design:

A retrospective cohort study was performed at a Level 1 academic trauma center. Patients injured at work between 01/01/07 and 01/01/12 and admitted with positive (BAC+) vs negative (BAC−) blood alcohol were compared using bivariate analysis.

Results:

Out of 823, 319 subjects were tested for BAC (38.8%), of whom 37 were BAC+ (mean 0.151 g/dL, range 0.015-0.371 g/dL). Age (41 years), sex (97.2% men), race, intensive care unit (ICU) and hospital length of stay (LOS), and mortality were similar between groups. Nearly half of BAC+ cases were farming injuries (18, 48.6%): Eight involved livestock, five involved all-terrain vehicles (ATVs), three involved heavy equipment, one fell, and one had a firearm injury. Eight (21.6%) were construction site injuries involving falls from a roof or scaffolding, five (13.5%) were semi-truck collisions, four (10.8%) involved falls from a vehicle in various settings, and two (5.4%) were crush injuries at an oilfield. BAC+ subjects were less likely to be injured in construction sites and oilfields, including vehicle-related falls (2.3 vs 33.9%, P < 0.0001). Over half of BAC+ (n = 20, 54%) subjects were alcohol dependent; three (8.1%) also tested positive for cocaine on admission. No BAC+ subjects were admitted to rehabilitation compared to 33 (11.7%) of BAC− subjects. Workers’ compensation covered a significantly smaller proportion of BAC+ patients (16.2 vs 61.0%, P < 0.0001).

Conclusions:

Alcohol use in the workplace is more prevalent than commonly suspected, especially in farming and other less regulated industries. BAC+ is associated with less insurance coverage, which probably affects resources available for post-discharge rehabilitation and hospital reimbursement.

Effect of alcohol in traumatic brain injury: is it really protective?

BACKGROUND

Studies have proposed a neuroprotective role for alcohol (ETOH) in traumatic brain injury (TBI). We hypothesized that ETOH intoxication is associated with mortality in patients with severe TBI.

METHODS

Version 7.2 of the National Trauma Data Bank (2007-2010) was queried for all patients with isolated blunt severe TBI (Head Abbreviated Injury Score ≥4) and blood ETOH levels recorded on admission. Primary outcome measure was mortality. Multivariate logistic regression analysis was performed to assess factors predicting mortality and in-hospital complications.

RESULTS

A total of 23,983 patients with severe TBI were evaluated of which 22.8% (n = 5461) patients tested positive for ETOH intoxication. ETOH-positive patients were more likely to have in-hospital complications (P = 0.001) and have a higher mortality rate (P = 0.01). ETOH intoxication was an independent predictor for mortality (odds ratio: 1.2, 95% confidence interval: 1.1-2.1, P = 0.01) and development of in-hospital complications (odds ratio: 1.3, 95% confidence interval: 1.1-2.8, P = 0.009) in patients with isolated severe TBI.

CONCLUSIONS

ETOH intoxication is an independent predictor for mortality in patients with severe TBI patients and is associated with higher complication rates. Our results from the National Trauma Data Standards differ from those previously reported. The proposed neuroprotective role of ETOH needs further clarification.

Acute alcohol intoxication, diffuse axonal injury and intraventricular bleeding in patients with isolated blunt traumatic brain injury

OBJECTIVE

The influence of blood alcohol level (BAL) on outcome remains unclear. This study investigated the relationships between BAL, type and number of diffuse axonal injury (DAI), intraventricular bleeding (IVB) and 6-month outcome.

METHODS

This study reviewed 419 patients with isolated blunt traumatic brain injury. First, it compared clinical and radiological characteristics between patients with good recovery and disability. Second, it compared BAL among DAI lesions. Third, it evaluated the correlation between the BAL and severity of IVB, number of DAI and corpus callosum injury lesions.

RESULTS

Regardless of BAL, older age, male gender, severe Glasgow Coma Scale score (<9), abnormal pupil, IVB and lesion on genu of corpus callosum were significantly related to disability. There were no significant differences between the BAL and lesions of DAI. Simple regression analysis revealed that there were no significant correlation between BAL and severity of IVB, number of DAI and corpus callosum injury lesions.

CONCLUSIONS

Acute alcohol intoxication was not associated with type and number of DAI lesion, IVB and disability. This study suggested that a specific type of traumatic lesion, specifically lesion on genu of corpus callosum and IVB, might be more vital for outcome.

Effect of cocaine use on outcomes in traumatic brain injury

Context:

Animal and molecular studies have shown that cocaine exerts a neuroprotective effect against cerebral ischemia.

Aims:

To determine if the presence of cocaine metabolites on admission following traumatic brain injury (TBI) is associated with better outcomes.

Settings and Design:

Level-1 trauma center, retrospective cohort.

Materials and Methods:

After obtaining Institutional Review Board (IRB) approval, the trauma registry was searched from 2006 to 2009 for all patients aged 15-55 years with blunt head trauma and non-head AIS <3. Exclusion criteria were pre-existing brain pathology and death within 30 min of admission. The primary outcome was in-hospital mortality; secondary outcomes were hospital length of stay (LOS), and Glasgow Outcome Score (GOS).

Statistical Analysis:

Logistic regression was used to determine the independent effect of cocaine on mortality. Hospital LOS was compared with multiple linear regression.

Results:

A total of 741 patients met criteria and had drug screens. The screened versus unscreened groups were similar. Cocaine positive patients were predominantly African-American (46% vs. 21%, P < 0.0001), older (40 years vs. 30 years, P < 0.0001), and had ethanol present more often (50.7% vs. 37.8%, P = 0.01). There were no differences in mortality (cocaine-positive 1.4% vs. cocaine-negative 2.7%, P = 0.6) on both univariate and multivariate analysis.

Conclusions:

Positive cocaine screening was not associated with mortality in TBI. An effect may not have been detected because of the low mortality rate. LOS is affected by many factors unrelated to the injury and may not be a good surrogate for recovery. Similarly, GOS may be too coarse a measure to identify a benefit.

Mortality from traumatic brain injury after reduction of alcohol prices: A population-based study from northern Finland

Aims: Traumatic brain injury (TBI) is the leading cause of death after trauma, and alcohol is a major risk factor for TBI. In Finland, alcohol taxes were cut by one third in 2004. This resulted in a marked increase of alcohol consumption. We investigated whether increased alcohol consumption influenced the number of fatal TBIs. Methods: All ( n = 318) fatal TBIs were identified from medico-legal reports during the years 1999, 2006 and 2007 among the residents of Oulu Province, Finland. Mortality rates were compared before and after alcohol price reduction. Alcohol involvement based on the presence of alcohol in body fluids and/or alcohol-related diseases recorded in death certificates. Results: The proportion of alcohol-related TBI deaths of all TBI deaths increased (from 1999 to 2007) among middle-aged people from 48% to 91% ( p = 0.001) but decreased among young adults from 74% to 41% ( p = 0.015). The overall TBI mortality rate did not increase. Fatal TBIs due to falls were significantly more commonly alcohol-related in 2006–2007 than in 1999 ( p = 0.003) and accumulated among middle-aged people. Conclusions: After the price reduction, alcohol-related fatal TBIs increased most among middle-aged people, and they were frequently caused by fall accidents. The reduction of alcohol prices did not increase the total number of fatal TBIs. Middle-aged and elderly subjects with TBI should be routinely asked for alcohol drinking and those with hazardous drinking habits should be guided for alcohol intervention.

Incidence of moderate-to-severe traumatic brain injuries after reduction in alcohol prices

OBJECTIVE

Alcohol may be involved in 40-50% of traumatic brain injuries (TBI). In Finland, the cutting of alcohol taxes by one third in 2004 resulted in a marked increase in per capita alcohol consumption. We investigated the consequences of increased alcohol consumption on the incidence of moderate-to-severe traumatic brain injury among a defined population.

MATERIAL AND METHODS

We identified all residents of Northern Ostrobothia with acute moderate-to-severe TBI admitted to Oulu University Hospital in 1999 and in 2007 as well as those who died on the scene without being admitted to the hospital. Alcohol involvement was recorded by similar methods and equally often during both years. Incidence rates were calculated as number of subjects per 100,000 population. Logistic regression was performed to determine which factors predicted fatal TBI and associated with alcohol-related TBI.

RESULTS

No significant increase from 1999 to 2007 occurred in the incidence of alcohol-related moderate-to-severe TBIs among the population of Northern Ostrobothnia. The total number of alcohol-related TBIs were 61/135 (45.2%) in 2007 and 52/126 (41.3%) 1999. Fall-related TBIs were more frequent in 2007 than in 1999. Alcohol and older age predicted fatal outcome. Alcohol was significantly (P < 0.001) more often present in fatal TBIs (83/156, 53.2%) than in non-fatal TBIs (30/105, 28.6%). Male sex, fall, suicide, and assault significantly associated with alcohol-related TBI.

CONCLUSIONS

The reduction in alcohol prices and the concomitant increase in alcohol consumption did not increase the incidence of alcohol-related moderate-to-severe TBI.

Dose-response relationship between in-hospital mortality and alcohol following acute injury

Although the relationship between alcohol and injury incidence is well researched, there continues to be dispute about the relationship between alcohol and mortality following an injury. Findings from past studies have varied primarily because of methodological issues and have failed to characterize the dose-response relationship. The main objective of this study was to evaluate the dose response relationship of in-hospital mortality and blood alcohol concentration (BAC). This study was a retrospective analysis of traumatic injuries occurring between 1995 and 2009 as reported by all level 1 and 2 trauma units in the State of Illinois. The study includes all patients with blood alcohol toxicological examination levels ranging from zero to 500 mg/dl (N = 190,612). The Illinois trauma registry includes all patients sustaining traumatic injuries and admitted to a trauma center for ≥12 h. A total of 6733 patients meeting the inclusion criteria died following admission. Patients that were dead on arrival and those that died during the initial assessment within the emergency room were excluded. In the adjusted multivariable model, a decrease in in-hospital mortality was strongly associated with an increase in blood alcohol concentration (adjusted OR = 0.83 per 100 mg/dl units change in BAC; CI 95%: 0.80, 0.85; p < 0.001). The direction of the dose response relationship was consistent across the stratified models, with the exception of patients suffering burns. The largest reduction of in-hospital case fatality rates by blood alcohol concentration was observed among patients suffering penetrating or severe injuries (Injury Severity Score ≥ 16). In the clinical setting, it is important to understand not only how to recognize intoxicated patients, but also how alcohol may affect the course of treatment. The consistency of the findings across the multivariable models indicates that blood alcohol concentration is strongly associated with lower in-hospital mortality among those that survive long enough to receive treatment in specialized trauma units.

Alcohol use at time of injury and survival following traumatic brain injury: results from the National Trauma Data Bank

OBJECTIVE

Premised on biological evidence from animal research, recent clinical studies have, for the most part, concluded that elevated blood alcohol concentration levels are independently associated with higher survival or decreased mortality in patients with moderate to severe traumatic brain injury (TBI). This study aims to provide some counterevidence to this claim and to further future investigations.

METHOD

Incident data were drawn from the largest U.S. trauma registry, the National Trauma Data Bank, for emergency department admission years 2002-2006. TBI was identified according to the National Trauma Data Bank's definition using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM), codes. To eliminate confounding, the exact matching method was used to match alcohol-positive with alcohol-negative incidents on sex, age, race/ethnicity, and facility. Logistic regression compared in-hospital mortality between 44,043 alcohol-positive and 59,817 matched alcohol-negative TBI incidents, with and without causes and intents of TBI and Injury Severity Score as covariates. A sensitivity analysis was performed within a subsample of isolated moderate to severe TBI incidents.

RESULTS

Alcohol use at the time of injury was found to be significantly associated with an increased risk for TBI. Including varied causes and intents of TBI and Injury Severity Score as potential confounders in the regression model explained away the statistical significance of the seemingly protective effect of alcohol against TBI mortality for all TBIs and for isolated moderate to severe TBIs.

CONCLUSIONS

The null finding shows that the purported reduction in TBI mortality attributed to positive blood alcohol likely is attributable to residual confounding. Accordingly, the risk of TBI associated with alcohol use should not be overlooked.

Correlating the Blood Alcohol Concentration with Outcome after Traumatic Brain Injury: Too Much Is Not a Bad Thing

Although recent evidence suggests a beneficial effect of alcohol for patients with traumatic brain injury (TBI), the level of alcohol that confers the protective effect is unknown. Our objective was to investigate the relationship between admission blood alcohol concentration (BAC) and outcomes in patients with isolated moderate to severe TBI. From 2005 to 2009, the Los Angeles County Trauma Database was queried for all patients ≥14 years of age with isolated moderate to severe TBI and admission serum alcohol levels. Patients were then stratified into four levels based on admission BAC: None (0 mg/dL), low (0-100 mg/dL), moderate (100-230 mg/dL), and high (≥230 mg/dL). Demographics, patient characteristics, and outcomes were compared across levels. In evaluating 3794 patients, the mortality rate decreased with increasing BAC levels (linear trend P < 0.0001). In determining the relationship between BAC and mortality, multivariable logistic regression analysis demonstrated a high BAC level was significantly protective (adjusted odds ratio 0.55; 95% confidence interval: 0.38-0.8; P = 0.002). In the largest study to date, a high (≥230 mg/dL) admission BAC was independently associated with improved survival in patients with isolated moderate to severe TBI. Additional research is warranted to investigate the potential therapeutic implications.

Ethanol intoxication is associated with a lower incidence of admission coagulopathy in severe traumatic brain injury patients

The aim of this study was to determine the impact of ethanol (ETOH) on the incidence of severe traumatic brain injury (sTBI)-associated coagulopathy and to examine the effect of ETOH on in-hospital outcomes in patients sustaining sTBI. Patients admitted to the surgical intensive care unit from June 2005 through December 2008 following sTBI, defined as a head Abbreviated Injury Scale (AIS) score ≥3, were retrospectively identified. Patients with a chest, abdomen, or extremity AIS score >3 were excluded to minimize the impact of extracranial injuries. Criteria for sTBI-associated coagulopathy included thrombocytopenia and/or elevated International Normalized Ratio (INR) and/or prolonged activated partial thromboplastin time (aPTT). The incidence of admission coagulopathy, in-hospital complications, and mortality were compared between patients who were ETOH positive [ETOH (+)] and ETOH negative [ETOH (-)]. During the study period, there were 439 patients with ETOH levels available for analysis. Overall, 46.5% (n=204) of these patients were ETOH (+), while 53.5% (n=235) were ETOH (-). Coagulopathy was significantly less frequent in the ETOH (+) patients compared to their ETOH (-) counterparts (5.4% versus 15.3%; adjusted p<0.001). In the forward logistic regression analysis, a positive ETOH level proved to be an independent protective factor for admission coagulopathy [OR (95% CI)=0.24 (0.10,0.54; p=0.001]. ETOH (+) patients had a significantly lower in-hospital mortality rate than ETOH (-) patients [9.8% versus 16.6%; adjusted p=0.011; adjusted OR (95% CI)=0.39 (0.19,0.81)]. For brain-injured patients arriving alive to the hospital, ETOH intoxication is associated with a significantly lower incidence of early coagulopathy and in-hospital mortality. Further research to establish the pathophysiologic mechanisms underlying any potential beneficial effect of ETOH on the coagulation system following sTBI is warranted.

Deadly partners: interdependence of alcohol and trauma in the clinical setting

Trauma is the leading cause of death for Americans aged 1 to 45. Over a third of all fatal motor vehicle collisions and nearly eighty percent of completed suicides involve alcohol. Alcohol can be both a cause of traumatic injury as well as a confounding factor in the diagnosis and treatment of the injured patient. Fortunately, brief interventions after alcohol-related traumatic events have been shown to decrease both trauma recidivism and long-term alcohol use. This review will address the epidemiology of alcohol-related trauma, the influence of alcohol on mortality and other outcomes, and the role of prevention in alcohol-related trauma, within the confines of the clinical setting.