Traumatic Brain Injuries during Development: Implications for Alcohol Abuse

Patterns of Alcohol Use in Hispanic Individuals with TBI over the Ten Years Post-Injury: A Model Systems Study

The study's aim was to examine alcohol consumption patterns and predictors of consumption across time among Hispanics with traumatic brain injury (TBI) in the U.S. within ten years post-injury. This longitudinal cohort study included 1342 Hispanic individuals (77.6% males) from the multi-site, longitudinal TBI Model Systems (TBIMS) database. The main outcome measures were consumption information, demographic, and injury characteristics. Across the full sample, alcohol consumption variables generally demonstrated quadratic movement characterized by an initial increase followed by a plateau or slight decrease over the ten years post-injury. The predictors of higher consumption were being men, single, with a history of excessive alcohol use, with a nonviolent mechanism of injury, shorter duration of PTA, and higher levels of education. Participants had a greater number of 5+ drinks/episode occurrences in the past month if they were men and had had a greater number of 5+ drinks/episode occurrences in the month before injury. There was no differential change in alcohol consumption over time as a function of these predictors. This study identified a profile of at-risk Hispanics with TBI for increased alcohol consumption. These individuals should be identified and targeted for early evidence-based alcohol intervention after TBI when results might be most favorable.

Reducing the incidence and mortality of traumatic brain injury in Latin America

Traumatic brain injury (TBI) represents a considerable portion of the global injury burden. The incidence of TBI will continue to increase in view of an increase in population density, an aging population, and the increased use of motor vehicles, motorcycles, and bicycles. The most common causes of TBI are falls and road traffic injuries. Deaths related to road traffic injury are three times higher in low-and middle-income countries (LMIC) than in high-income countries (HIC). The Latin American Caribbean region has the highest incidence of TBI worldwide, primarily caused by road traffic injuries. Data from HIC indicates that road traffic injuries can be successfully prevented through concerted efforts at the national level, with coordinated and multisector responses to the problem. Such actions require implementation of proven measures to address the safety of road users and the vehicles themselves, road infrastructure, and post-crash care. In this review, we focus on the epidemiology of TBI in Latin America and the implementation of solutions and preventive measures to decrease mortality and long-term disability.

The negative influence of chronic alcohol abuse on acute cognitive recovery after a traumatic brain injury

OBJECTIVE

Cognitive recovery after a traumatic brain injury (TBI) may be negatively affected by a prior alcohol use disorder (AUD). This study aims to compare the cognitive recovery of patients who had comorbid TBI and AUD relative to TBI alone and investigate the influence of blood alcohol level (BAL) at hospital admission on this recovery.

METHOD

The sample consisted of 42 patients who had sustained a TBI (mild or moderate) and had an AUD diagnosis (TBI+AUD), and 42 patients who had sustained a TBI alone (TBI). The Brief Cognitive Exam in Traumatology (EXACT), designed to evaluate cognitive functions in the acute phase of TBI was administered (± 2 weeks post-injury).

RESULTS

After controlling for BAL at admission, the TBI+AUD group had a lower EXACT total score compared to the TBI group. The negative influence of age on the results was more pronounced in the TBI+AUD group. The number of intoxicated patients at admission was also higher in this group, although there was no correlation between BAL at admission and cognitive outcome.

CONCLUSION

The presence of an AUD diagnosis seems to exert a greater negative influence on cognitive recovery following a mild/moderate TBI than BAL at admission, especially in older patients.

The Role of Neuroinflammation in Neuropsychiatric Disorders Following Traumatic Brain Injury: A Systematic Review

BACKGROUND

Neuropsychiatric symptoms are common following traumatic brain injury (TBI), but their etiological onset remains unclear. Mental health research implicates neuroinflammation in the development of psychiatric disorders. The presence of neuroinflammatory responses after TBI thus prompts an investigation of their involvement in the emergence of neuropsychiatric disorders postinjury.

OBJECTIVE

Review the literature surrounding the role of neuroinflammation and immune response post-TBI in the development of neuropsychiatric disorders.

METHODS

A search of scientific databases was conducted for original, empirical studies in human subjects. Key words such as "neuroinflammation," "TBI," and "depression" were used to identify psychopathology as an outcome TBI and the relation to neuroinflammatory response.

RESULTS

Study results provide evidence of neuroinflammation mediated post-TBI neuropsychiatric disorders including anxiety, trauma/stress, and depression. Inflammatory processes and stress response dysregulation can lead to secondary cell damage, which promote the development and maintenance of neuropsychiatric disorders postinjury.

CONCLUSION

This review identifies both theoretical and empirical support for neuroinflammatory response as feasible mechanisms underlying neuropsychiatric disorders after TBI. Further understanding of these processes in this context has significant clinical implications for guiding the development of novel treatments to reduce psychiatric symptoms postinjury. Future directions to address current limitations in the literature are discussed.

Traumatic Brain Injury and Treatment of Behavioral Health Conditions

Traumatic brain injury (TBI) is a common neurological condition that results from an external force altering normal brain function, whether temporarily or permanently. A concussion is one type of TBI. TBIs vary greatly in severity, which concomitantly creates tremendous variability in their manifestation. The fingerprint of TBI is damage to the frontal areas of the brain, which, with sufficient magnitude, results in impairment of a person's ability to regulate cognition, emotion, and behavior. These consequences of TBI make recognition in the context of treating behavioral health conditions of utmost importance. TBI not only causes behavioral health problems but also produces associated deficits that can undermine the effectiveness of treatment for a behavioral health condition. This overview delineates key characteristics of TBI and describes its association with behavioral health conditions. Mechanisms underlying the relationship between TBI and behavioral health are presented, and a series of recommendations for professionals are proposed. This article is intended to raise awareness about TBI and simultaneously introduce key concepts for accommodating the effects of TBI in behavioral health care.

Pathophysiology of Pediatric Traumatic Brain Injury

The national incidence of traumatic brain injury (TBI) exceeds that of any other disease in the pediatric population. In the United States the Centers for Disease Control and Prevention (CDC) reports 697,347 annual TBIs in children ages 0–19 that result in emergency room visits, hospitalization or deaths. There is a bimodal distribution within the pediatric TBI population, with peaks in both toddlers and adolescents. Preclinical TBI research provides evidence for age differences in acute pathophysiology that likely contribute to long-term outcome differences between age groups. This review will examine the timecourse of acute pathophysiological processes during cerebral maturation, including calcium accumulation, glucose metabolism and cerebral blood flow. Consequences of pediatric TBI are complicated by the ongoing maturational changes allowing for substantial plasticity and windows of vulnerabilities. This review will also examine the timecourse of later outcomes after mild, repeat mild and more severe TBI to establish developmental windows of susceptibility and altered maturational trajectories. Research progress for pediatric TBI is critically important to reveal age-associated mechanisms and to determine knowledge gaps for future studies.

Investigating cannabis use and associated symptoms among university students with and without a history of concussion

Recently, there has been a growing interest in the use of cannabis after traumatic brain injury (TBI); however, little is known about the long-term effects of cannabis on milder injuries and post-concussive symptoms. Further, substance use often increases post-TBI and, thus, individuals who chronically use cannabis may unknowingly be exceeding safe or therapeutic doses. The current cross-sectional study explores the prevalence of cannabis use among university students with and without a history of concussion and examines the relationship between concussion and post-concussive symptoms as a function of cannabis use. Eighty-four undergraduates (n = 51 without a prior concussion; n = 33 with a prior concussion) completed a series of questionnaires, capturing their head injury history, current and past substance use, and post-concussive symptomatology. Results indicated that those with a history of concussion were more likely to use cannabis and had higher cannabis use severity scores compared to those without a previous concussion. Further, among cannabis users only, concussion severity demonstrated a significant positive association with post-concussive symptom (e.g., headaches, memory problems) severity (i.e., frequency, intensity, duration). Taken together, the long-term use of cannabis may be detrimental to individuals with a history of concussion, exacerbating, rather than mitigating, post-concussive symptoms.

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.

Alcohol Use Disorder Increases Risk of Traumatic Brain Injury-Related Hospitalization: Insights From 3.8 Million Children and Adolescent Inpatients

Objectives

We conducted a cross-sectional study to identify the demographic predictors of traumatic brain injury (TBI), and the risk of association of psychiatric comorbidities including alcohol use disorder (AUD) and TBI-related hospitalizations in the children and adolescent population.

Methods

We included 3,825,523 children and adolescent inpatients (age 8-18 years) using the nationwide inpatient sample (NIS) database (2010-2014), and 61,948 inpatients had a primary diagnosis of TBI. These inpatients were grouped by comorbid AUD (N = 2,644). Multivariable logistic regression model adjusted for demographics, and psychiatric comorbidities including other substance use disorders (SUDs) was used to evaluate the odds ratio (OR) of AUD as a risk factor for TBI-related hospitalization.

Results

The majority of the TBI inpatients were adolescents (12-18 years, 82.2%), males (71.2%), and whites (59.2%). Males had three times higher odds (95% CI 3.14-3.26) for TBI-related hospitalization compared to females. Among psychiatric comorbidities, mood (4.1%) and anxiety (2.2%) disorders were prevalent in TBI inpatients, and were not associated with increased odds for TBI-related hospitalization. Among SUD, alcohol and tobacco use (4.4% each), and cannabis use (3.5%) were prevalent, and among all substances, AUD was associated with higher odds (OR 3.5, 95% CI 3.35-3.67) of TBI-related hospitalization. These patients with TBI and comorbid AUD also had higher odds for abusing stimulants (OR 5.11, 95% CI 3.85-6.77), cannabis (OR 4.69, 95% CI 4.12-5.34), and tobacco (OR 3.77, 95% CI 3.34-4.27).

Conclusion

AUD is an independent risk factor for TBI-related hospitalization with an increased risk of 50% in the children and adolescent population compared to non-alcohol users. TBI inpatients with AUD are prevalent in white, and male adolescents. These at-risk populations are also at higher risk of comorbid mood disorders and increased substance use including stimulants, cannabis, and tobacco.

Is Pediatric Traumatic Brain Injury Associated with Adult Alcohol Misuse?

Evidence suggests that pediatric traumatic brain injury (TBI) may be causally related to alcohol misuse later in life; however, the nature and extent of the association has not been well described. This study examined the relationship between pediatric TBI and adult alcohol misuse in a population sample ≥20 years of age. We sought to determine (1) whether first self-reported incidence of TBI with loss of consciousness (LOC) before the age of 20 increased the risk for alcohol misuse later in life; and (2) whether sex, injury severity, and age at time of injury modified the association. We found a greater likelihood of binge but not heavy drinking for those whose first self-reported TBI with LOC occurred before the age of 20 when compared with those whose first self-reported TBI with LOC occurred later in life (28.5% vs. 20.4%, p = 0.003). When limited to those with only mild TBI, the relationship to binge drinking remained significant (31.9% vs. 19.3%, p < 0.001) and was evident for both males (38.4% vs. 25.6%, p = 0.016) and females (20.9% vs. 12.4%, p = 0.044). When controlling for sex, age, and race/ethnicity, reporting a first TBI with LOC before age 20 was associated with binge drinking only for those with mild TBI (adjusted odds ratio [AOR] = 1.32; 95% confidence interval [CI] = 1.00-1.74). Results also showed that those with first TBI with LOC occurring between the ages of 10 and 19 years were more likely to binge drink as adults than those first injured earlier in life, regardless of TBI severity. Further research is needed at both the epidemiological and pre-clinical levels to better understand this relationship.

The Diagnostic Value of Neuron-Specific Enolase in Children with Mild Blunt Trauma Requiring Cranial CT Scan

Background

The present study was conducted to investigate the relationship between serum levels of enolase and pathological findings obtained from CT scans of the brain in children with mild blunt brain trauma and help with a more accurate diagnosis of brain injuries.

Methods

The present observational study was conducted on children presenting with head traumas to the emergency department (ED) of Golestan Hospital in Ahvaz, Iran in 2016. A venous blood sample was immediately taken by the ward nurse from all the eligible patients within 6 hrs of the incident after obtaining their information, performing initial examinations and their initial stabilization. Laboratory serum levels and the corresponding interpretations of CT scans of the brain were collected, recorded and then evaluated and analyzed.

Results

A total of 62 children with mild blunt brain trauma were included in the study. A significant difference was observed between the positive CT scan group (2.7±9.74 µg/L) and the negative group (4.23±1.33 µg/L) in terms of serum levels of enolase (P<0.0001). The area under the receiver operating characteristic (ROC) curve was 0.992 for serum levels of enolase in diagnosing brain lesions caused by mild head traumas. Moreover, with a cut-off point of 6.97 µg/L, brain lesions could be detected with a sensitivity of 93.55% and a specificity of 100%.

Conclusion

Serum levels of enolase were found to be higher in patients with brain injuries. This highly accurate diagnostic biomarker can be recommended for estimating the presence of brain lesions associated with mild head traumas in infants.

Alcohol misuse and traumatic brain injury: a review of the potential roles of dopaminergic dysfunction and physiological underarousal post-injury

Although many researchers have demonstrated an increase in alcohol use following traumatic brain injury (TBI), there is also a body of research indicating that alcohol misuse predisposes one to injury and precedes TBI. Accordingly, various mechanisms have been proposed (e.g., self-medication, dampened levels of arousal, dopaminergic dysfunction, etc.) and variable results have emerged. This paper reviews the empirical evidence, for and against, TBI as a risk factor for alcohol misuse. In particular, this paper focuses on the brain-behavior relationships involved and examines the roles of physiological underarousal and dopaminergic dysfunction in the development of alcohol misuse after injury. Alcohol misuse impedes community reintegration among TBI survivors and creates additional rehabilitative challenges. Thus, in order to inform and improve treatment outcomes among this vulnerable population, a deeper understanding of the neural mechanisms implicated is needed.

Minocycline blocks traumatic brain injury-induced alcohol consumption and nucleus accumbens inflammation in adolescent male mice

Alcohol use is a well characterized risk factor for traumatic brain injury (TBI); however, emerging clinical and experimental research suggests that TBI may also be an independent risk factor for the development of alcohol use disorders. In particular, TBIs incurred early in life predict the development of problem alcohol use and increase vulnerability to neuroinflammation as a consequence of alcohol use. Critically, the neuroinflammatory response to alcohol, mediated in large part by microglia, may also function as a driver of further alcohol use. Here, we tested the hypothesis that TBI increases alcohol consumption through microglia-mediated neuroinflammation. Mice were injured as juveniles and alcohol consumption and preference were assessed in a free-choice voluntary drinking paradigm in adolescence. TBI increased alcohol consumption; however, treatment with minocycline, an inhibitor of microglial activation, reduced alcohol intake in TBI mice to sham levels. Moreover, a single injection of ethanol (2 g/kg) significantly increased microglial activation in the nucleus accumbens and microglial expression of the proinflammatory cytokine IL-1β in TBI, but not sham or minocycline-treated, mice. Our data implicate TBI-induced microglial activation as a possible mechanism for the development of alcohol use disorders.

Alcohol Use Disorder and Traumatic Brain Injury

Alcohol use and traumatic brain injury (TBI) are inextricably and bidirectionally linked. Alcohol intoxication is one of the strongest predictors of TBI, and a substantial proportion of TBIs occur in intoxicated individuals. An inverse relationship is also emerging, such that TBI can serve as a risk factor for, or modulate the course of, alcohol use disorder (AUD). Critically, alcohol use after TBI is a key predictor of rehabilitation outcomes, prognosis, and additional head injuries. This review provides a general overview of the bidirectional relationship between TBI and AUD and a discussion of potential neuropsychological and neurobiological mechanisms that might underlie the relationship.

An Examination of Behavioral and Neuronal Effects of Comorbid Traumatic Brain Injury and Alcohol Use

BACKGROUND

Chronic alcohol use disorders (AUDs) and traumatic brain injury (TBI) are highly comorbid and share commonly affected neuronal substrates (i.e., prefrontal cortex, limbic system, and cerebellum). However, no studies have examined how combined physical trauma and heavy drinking affect neurocircuitry relative to heavy drinking alone.

METHODS

The current study investigated whether comorbid AUDs and mild or moderate TBI (AUDs+TBI) would negatively affect maladaptive drinking behaviors (n = 90 AUDs+TBI; n = 62 AUDs) as well as brain structure (i.e., increased atrophy; n = 62 AUDs+TBI; n = 44 AUDs) and function (i.e., activation during gustatory cue reactivity; n = 55 AUDs+TBI; n = 37 AUDs) relative to AUDs alone.

RESULTS

Participants reported a much higher incidence of trauma (59.2%) compared with the general population. There were no differences in demographic and clinical measures between groups, suggesting that they were well matched. Although maladaptive drinking behaviors tended to be worse for the AUDs+TBI group, effect sizes were small and not statistically significant. Increased alcohol-cue reactivity was observed in bilateral anterior insula and orbitofrontal cortex, anterior cingulate cortex, medial prefrontal cortex, posterior cingulate cortex, dorsal striatum, thalamus, brainstem, and cerebellum across both groups relative to a carefully matched appetitive control. However, there were no significant differences in structural integrity or functional activation between AUDs+TBI and AUDs participants, even when controlling for AUD severity.

CONCLUSIONS

Current results indicate that a combined history of mild or moderate TBI was not sufficient to alter drinking behaviors and/or underlying neurocircuitry at detectable levels relative to heavy drinking alone. Future studies should examine the potential long-term effects of combined alcohol and trauma on brain functioning.