Traumatic brain injury, dissociation, and posttraumatic stress disorder in road traffic accident survivors

Unconditioned response to an aversive stimulus as predictor of response to conditioned fear and safety: A cross-species study

Safety signals predict the non-occurrence of an aversive event, thereby inhibiting fear responses. Previous research has shown that conditioned safety learning is impaired in patients suffering from post-traumatic stress disorder (PTSD). Using a translational approach, the present study aimed to investigate whether individual responses to an aversive unconditioned stimulus (US) in rats (basic science), non-traumatized (pre-clinical) or traumatized humans (clinical) predicts their response to a conditioned fear or safety stimulus. Using three different archival datasets, the unconditioned response (UCR) to the US during fear or safety conditioning was assessed in rats, non-traumatized humans, and trauma-exposed humans. The response to learned fear (CS+; context) and safety (CS-) was measured by the modulation of the startle response (rats, traumatized humans) or skin conductance response (non-traumatized humans). Our results showed that all groups with low UCR and those with high UCR from the rodent or non-traumatized human samples displayed lower fear response to the CS- than to the CS+ . Traumatized humans with high UCR showed similarly high responses to the CS+ and CS-. While all groups showed a positive association between the UCR and CS+ response, the UCR correlated positively with the CS- response in traumatized humans only. Our findings suggest that an elevated response to aversive stimuli predicts deficits in conditioned safety memory in those at risk for trauma-related disorders and confirms that impaired safety learning could be a valid biomarker for these diseases.

Psychological Distress of Patients Experiencing Different Types of Road Traffic Injuries in Vietnam

Road-related injuries are often catastrophic, and the eighth leading cause of all-aged mortality. While psychological problems, including anxiety, driving phobia, and post-traumatic stress have been found to be common among injured survivors, the literature in this area is still limited. This study aimed to evaluate the prevalence of distress between different types of road injuries among 413 patients in Thai Binh hospitals from October to December 2018. The Kessler Psychological Distress Scale (K6) was used to assess mental health status. Sociodemographic and clinical characteristics were also collected. The results of Multiple Logistic and Tobit regression models were utilized. Psychological issues were found in 13.8% of the participants. In terms of K6 profile, nervous, restless/fidgety, and “everything was an effort” were the three most frequently endorsed aspects. Having soft-tissue injuries had a 0.32-time lower likelihood of psychological distress compared to those having other injuries. Additionally, patients who were diagnosed with fractures were 4.5-times more likely to report psychological distress. Our finding highlights the need for psychological screening to reduce disabilities associated with non-fatal injury related to road traffic crashes.

Management of mild traumatic brain injury

Mild traumatic brain injury (TBI) is common and associated with a range of diffuse, non-specific symptoms including headache, nausea, dizziness, fatigue, hypersomnolence, attentional difficulties, photosensitivity and phonosensitivity, irritability and depersonalisation. Although these symptoms usually resolve within 3 months, 5%–15% of patients are left with chronic symptoms. We argue that simply labelling such symptoms as ‘postconcussional’ is of little benefit to patients. Instead, we suggest that detailed assessment, including investigation, both of the severity of the ‘mild’ injury and of the individual symptom syndromes, should be used to tailor a rehabilitative approach to symptoms. To complement such an approach, we have developed a self-help website for patients with mild TBI, based on neurorehabilitative and cognitive behavioural therapy principles, offering information, tips and tools to guide recovery: www.headinjurysymptoms.org.

Post-Traumatic Stress Disorder after Civilian Traumatic Brain Injury: A Systematic Review and Meta-Analysis of Prevalence Rates

Post-traumatic stress disorder (PTSD) is a commonly diagnosed psychiatric disorder following traumatic brain injury (TBI). Much research on PTSD and TBI has focused on military conflict settings. Less is known about PTSD in civilian TBI. We conducted a systematic review and meta-analysis on the prevalence of PTSD after mild and moderate/severe TBI in civilian populations. We further aimed to explore the influence of methodological quality and assessment methods.

A systematic literature search was performed on studies reporting on PTSD in civilian TBI, excluding studies on military populations. The risk of bias was assessed using the MORE (Methodological evaluation of Observational REsearch) checklist. Meta-analysis was conducted for overall prevalence rates for PTSD with sensitivity analyses for the severity of TBI.

Fifty-two studies were included, of which 31 were graded as low risk of bias. Prevalence rates of PTSD in low risk of bias studies varied widely (2.6–36%) with a pooled prevalence rate of 15.6%. Pooled prevalence rates of PTSD for mild TBI (13.5%, 95% confidence interval [CI]: 11.7–15.3; I² = 2%) did not differ from moderate/severe TBI (11.8, 95% CI: 7.5–16.1; I² = 63%). Similar rates were reported in studies using different approaches and times of assessment. Although most studies that compared participants with TBI with trauma patients and healthy controls found no difference in prevalence rates of PTSD, a meta-analysis across studies revealed a higher prevalence of PTSD in patients with TBI (odds ratio [OR]: 1.73, 95% CI: 1.21–2.47).

This review highlights variability between studies and emphasizes the need for higher-quality studies. Further research is warranted to determine risk factors for the development of PTSD after TBI.

Differences in Post-Traumatic Stress Disorder Symptoms among Post-9/11 Veterans with Blast- and Non-Blast Mild Traumatic Brain Injury

The relationship between traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) has been difficult to disentangle, in part due to the commonality of incidents that can cause both conditions, as well as high rates of comorbidity between the two conditions. Inconsistent findings may be related to different study characteristics and types of mild TBI (mTBI) sustained (e.g., blast, non-blast). The objective of this study was to determine the association of blast- versus non-blast-related TBIs with long-term PTSD symptoms after controlling for demographic variables and trauma exposure. The sample included 230 post-9/11 veterans who experienced a blast-related mTBI (n = 29), non-blast mTBI (n = 74), combined blast and non-blast mTBI (n = 40), or no TBI (n = 87). As hypothesized, a between-groups analysis of covariance (ANCOVA) revealed that, after controlling for demographics, combat exposure, and prior trauma, PTSD symptoms among individuals with blast-related mTBI and combined blast and non-blast mTBI were significantly higher compared with non-blast-related mTBI and no TBI. These data suggest that blast-related mTBI is associated with more severe long-term PTSD symptoms.

Prevalence of acute stress disorder among road traffic accident survivors: a meta-analysis

BACKGROUND

Road traffic accident (RTA), an unexpected traumatic event, may not only lead to death and serious physical injuries, but also could put survivors at an increased risk for a wide range of psychiatric disorders, particularly acute stress disorder (ASD). Early assessment of trauma-related psychological responses is important because acute trauma responses in the early post-traumatic period are among the robust predictors of long-term mental health problems. However, estimates of the prevalence of ASD among RTA survivors varied considerably across studies. Therefore, this meta-analysis aimed to identify the pooled prevalence of ASD among RTA survivors.

METHODS

A systematic literature search in the databases of PubMed, PsycINFO, PsycARTICLES, Embase and Web of Science was performed from their inception dates to December 2017. Subject headings were used to identify relevant articles, and the search strategy was adjusted across databases. Heterogeneity across studies was evaluated by Cochran's χ² test and quantified by the I² statistic. Subgroup analyses were performed to identify the pooled prevalence in relation to the country of study, instrument used to identify ASD, age, gender and traumatic brain injury. When significant heterogeneity was observed, the influence of some potential moderators was explored using meta-regression analyses.

RESULTS

Thirteen eligible studies conducted in 8 countries were included. A total of 2989 RTA survivors were assessed, of which 287 were identified with ASD. The overall heterogeneity was high across studies (I²=96.8%, P < 0.001), and the pooled prevalence of ASD among RTA survivors was 15.81% (95% confidence interval: 8.27-25.14%). Subgroup analyses indicated that the prevalence of ASD among RTA survivors differed significantly with regard to the country of study, instrument used to identify ASD, age and gender (P < 0.05). Meta-regression analyses showed that mean age of participants and quality assessment score were significant moderators for heterogeneity (P < 0.05).

CONCLUSIONS

Nearly one-sixth of RTA survivors suffer from ASD, indicating the need for regular assessment of early trauma responses among RTA survivors, as well as the importance of implementing early psychological interventions.

Prevalence of and Risk Factors for Anxiety and Depressive Disorders after Traumatic Brain Injury: A Systematic Review

This review examined pre- and post-injury prevalence of, and risk factors for, anxiety disorders and depressive disorders after traumatic brain injury (TBI), based on evidence from structured diagnostic interviews. A systematic literature search was conducted in EMBASE, MEDLINE, Cochrane Central, PubMed, PsycINFO, and Google Scholar. We identified studies in civilian adults with TBI reporting on the prevalence of anxiety and depressive disorders using structured diagnostic interviews and assessed their quality. Pooled pre- and post-injury prevalence estimates of anxiety disorders and depressive disorders were computed. A total of 34 studies described in 68 publications were identified, often assessing anxiety disorders (n = 9), depressive disorders (n = 7), or a combination of disorders (n = 6). Prevalence rates of psychiatric disorders varied widely. Pooled prevalence estimates of anxiety and depressive disorders were 19% and 13% before TBI and 21% and 17% in the first year after TBI. Pooled prevalence estimates increased over time and indicated high long-term prevalence of Axis I disorders (54%), including anxiety disorders (36%) or depressive disorders (43%). Females, those without employment, and those with a psychiatric history before TBI were at higher risk for anxiety and depressive disorders after TBI. We conclude that a substantial number of patients encounter anxiety and depressive disorders after TBI, and that these problems persist over time. All health care settings should pay attention to the occurrence of psychiatric symptoms in the aftermath of TBI to enable early identification and treatment of these disorders and to enhance the recovery and quality of life of TBI survivors.

Diffuse traumatic axonal injury in mice induces complex behavioural alterations that are normalized by neutralization of interleukin-1β

Widespread traumatic axonal injury (TAI) results in brain network dysfunction, which commonly leads to persisting cognitive and behavioural impairments following traumatic brain injury (TBI). TBI induces a complex neuroinflammatory response, frequently located at sites of axonal pathology. The role of the pro-inflammatory cytokine interleukin (IL)-1β has not been established in TAI. An IL-1β-neutralizing or a control antibody was administered intraperitoneally at 30 min following central fluid percussion injury (cFPI), a mouse model of widespread TAI. Mice subjected to moderate cFPI (n = 41) were compared with sham-injured controls (n = 20) and untreated, naive mice (n = 9). The anti-IL-1β antibody reached the target brain regions in adequate therapeutic concentrations (up to ~30 μg/brain tissue) at 24 h post-injury in both cFPI (n = 5) and sham-injured (n = 3) mice, with lower concentrations at 72 h post-injury (up to ~18 μg/g brain tissue in three cFPI mice). Functional outcome was analysed with the multivariate concentric square field (MCSF) test at 2 and 9 days post-injury, and the Morris water maze (MWM) at 14-21 days post-injury. Following TAI, the IL-1β-neutralizing antibody resulted in an improved behavioural outcome, including normalized behavioural profiles in the MCSF test. The performance in the MWM probe (memory) trial was improved, although not in the learning trials. The IL-1β-neutralizing treatment did not influence cerebral ventricle size or the number of microglia/macrophages. These findings support the hypothesis that IL-1β is an important contributor to the processes causing complex cognitive and behavioural disturbances following TAI.

Social, cultural, and other diversity issues in the traumatic stress field

This chapter describes how the impact of psychological trauma and posttraumatic stress disorder (PTSD) differ, depending on individual differences and the social and cultural context and culture-specific teachings and resources available to individuals, families, and communities. A social-ecological framework is used to differentiate the impact of exposure to traumatic stressors and the development of (or resistance to) PTSD, based on the individual’s or group’s (i) personal, unique physical characteristics, including skin color, racial background, gender, and sexual orientation; and (ii) family, ethnocultural, and community membership, including majority or minority group status, religious beliefs and practices, socioeconomic resources, and political and civic affiliations. While personal, familial, social, and cultural factors can be a positive resource contributing to safety and well-being, they also can be a basis for placing the person, group, or entire community or population in harm’s way or at heightened risk of developing PTSD.

Neurologically-related sequelae associated with mild traumatic brain injury

OBJECTIVE

Mild traumatic brain injury (mTBI) accounts for more than 75% of traumatic brain injuries every year. This study examines the temporal association between non-blast mTBI and the onset of neurologic sequelae to illuminate risks of post-concussive syndrome, epilepsy and chronic pain.

METHODS

A large historical prospective study was conducted utilizing electronically-recorded demographic, medical and military-specific data for over half a million active duty US Air Force Airmen. This study utilized diagnostic codes to identify mTBI exposures, two control groups and three post-mTBI time periods. Adjusted hazard ratios (HRs) were calculated using Cox proportional hazards modelling.

RESULTS

HRs were higher when mTBI exposed Airmen were compared with the full cohort and lower when compared with the other injured group. When compared to the other injured group, mTBI was positively associated with epilepsy/recurrent seizure outcomes, post-concussive syndrome and pain disorders. HRs tended to be highest within the first 30 days and decreased over time.

CONCLUSIONS

Findings support that mTBI may have a prolonged neurological impact. Findings are also likely generalizable to young adult populations with exposure to non-blast related mTBI, including civilians, as those included in this study were young adults with a high prevalence of recreational/sports and motor vehicle injuries.

Traumatic brain injury and posttraumatic stress disorder

Given the upsurge of research in posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI), much of which has focused on military samples who served in Iraq and Afghanistan, the purpose of this article is to review the literature published after September 11th, 2001 that addresses the epidemiology, pathophysiology, evaluation, and treatment of PTSD in the context of TBI.

Head injury and loss of consciousness raise the likelihood of developing and maintaining PTSD symptoms

Mild traumatic brain injury has been associated with higher prevalence of posttraumatic stress disorder (PTSD). The extent to which head injury or loss of consciousness predicts PTSD is unknown. To evaluate the contribution of head injury and loss of consciousness to the occurrence of PTSD, we made a longitudinal evaluation of 1,260 road accident survivors admitted to the emergency department with head injury (n = 287), head injury and loss of consciousness (n = 115), or neither (n = 858). A telephone-administered posttraumatic symptoms scale inferred PTSD and quantified PTSD symptoms at 10 days and 8 months after admission. The study groups had similar heart rate, blood pressure, and pain levels in the emergency department. Survivors with loss of consciousness and head injury had higher prevalence of PTSD and higher levels of PTSD symptoms, suggesting that patients with head injury and loss of consciousness reported in the emergency department are at higher risk for PTSD.

Aripiprazole improves various cognitive and behavioral impairments after traumatic brain injury: a case report

Various types of cognitive and behavioral impairments occur after traumatic brain injury. We present a case exhibiting psychotic symptoms such as irritability, dysphoria, anxiety and insomnia with severe brain dysfunction due to a right temporal lobe contusion incurred in a traffic accident. The patient did not sufficiently respond to rehabilitation or treatment with any pharmacotherapy. In the present case, aripiprazole dramatically improved the patient's symptoms and cognitive function. We evaluated the case using the Wechsler Adult Intelligence Scale-Revised and the Wechsler Memory Scale Revised between baseline and 5 years later.

Impaired safety signal learning may be a biomarker of PTSD

A dysregulated fear response is one of the hallmark clinical presentations of patients suffering from posttraumatic stress disorder (PTSD). These patients show over-generalization of fear and in tandem an inability to inhibit fear responses in the presence of safety. Here, we summarize our recent findings using a conditional discrimination paradigm, which assesses safety signal processing (AX+/BX-) in combat and civilian PTSD populations. Overall, PTSD subjects demonstrate a lack of safety signal learning and an inability to modulate the fear responses with safety cues. We then review studies of the neurobiology of fear expression and inhibition in humans and non-humans, in order to provide a background for preliminary studies using reverse translation procedures in which the same AX+/BX- paradigm was used in rhesus macaques. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.

Tailoring therapeutic strategies for treating posttraumatic stress disorder symptom clusters

According to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, posttraumatic stress disorder (PTSD) is characterized by three major symptom clusters following an event that elicited fear, helplessness, or horror. This review will examine each symptom cluster of PTSD separately, giving case study examples of patients who exhibit a preponderance of a given symptom domain. We use a translational approach in describing the underlying neurobiology that is relevant to particular symptoms and treatment options, thus showing how clinical practice can benefit from current research. By focusing on symptom clusters, we provide a more specific view of individual patient's clinical presentations, in order to better address treatment needs. Finally, the review will also address potential genetic approaches to treatment as another form of individualized treatment.

Cognitive sequelae of blast-related versus other mechanisms of brain trauma

The use of improvised explosive devices has become the hallmark of modern warfare and has resulted in an ever-increasing number of blast-related traumatic brain injuries (TBIs). Despite this fact, very little is actually known about the cognitive sequelae of blast-related TBIs. The purpose of the current study was to compare patterns of performance on neuropsychological measures in subjects who have sustained TBIs as a result of blast (or explosion) with those who have sustained TBIs from non-blast or blunt force trauma (motor vehicle accident, fall, assault, etc.). Participants were categorized as blast-related TBI or non-blast-related TBI and according to severity of injury (mild or moderate-to-severe). No main effects were observed in analysis of covariance between blast-related TBI participants and non-blast-related TBI participants across any of the neuropsychological variables, although an interaction was observed on a visual memory test showing stronger performance for mild blast-related and poorer performance for moderate-to-severe blast-related participants compared with both non-blast groups. Overall, the results do not provide any strong evidence that blast is categorically different from other TBI mechanisms, at least with regard to cognitive sequelae on select measures. Additional findings included a marginally increased incidence of reported posttraumatic stress disorder symptoms among blast-injured participants. (JINS, 2009, 15, 1-8.).

The independent predictive value of peritraumatic dissociation for PTSD symptomatology after type I trauma: a systematic review of prospective studies

We conducted a systematic review of prospective studies examining the independent predictive value of peritraumatic dissociation (PD) for posttraumatic stress disorder (PTSD) symptomatology following single traumatic events. Insight into the independent predictive value may help to identify victims at risk for PTSD symptomatology. For this purpose a literature search was carried out using the online databases PsycINFO, Medline/Pubmed, and PILOTS. Studies were included if they were published in peer-reviewed journals (before 2007), focused on more or less single traumatic events (Type I trauma), assessed PD within 1 month, had follow-ups 3 months or later, and which controlled for mental health problems at the time PD was assessed. The majority of the 17 identified studies showed no or only weak indications of an independent predictive value of PD for PTSD symptomatology following type I traumas. Only 3 of the 6 studies with positive results reported a strong independent predictive value of PD. Although bivariately associated with PTSD symptomatology, there is no general consensus across prospective Type I trauma studies that PD qualifies as an important independent predictor of PTSD symptomatology. Results indicate that initial mental health problems, among other factors, are better predictors of PTSD symptomatology than PD.

The prevalence of post traumatic stress disorder in survivors of ICU treatment: a systematic review

OBJECTIVE

To determine the prevalence of post traumatic stress disorder in survivors of intensive care treatment.

DESIGN

Systematic literature review including Medline, Embase, CINAHL, PsycINFO and references from identified papers.

STUDY SELECTION

Studies determining the prevalence of PTSD in adult patients who had at least 24[Symbol: see text]h treatment on an intensive care unit. Independent duplicate data extraction. Study quality was evaluated in terms of study design and method and timing of PTSD assessment. DATA SYNTHESIS AND RESULTS: Of the 1472 citations identified, 30 studies meeting the selection criteria were reviewed. PTSD was diagnosed by standardised clinical interview alone in 2 studies. A self-report measure alone was used in 19 studies to measure PTSD symptomatology. The remaining 9 studies applied both standardised clinical interview and a self-report measure. The reported prevalence of PTSD was 0-64% when diagnosed by standardised clinical interview and 5-64% by self-report measure. PTSD assessments occurred 7 days to 8 years after intensive care discharge.

CONCLUSION

The true prevalence of PTSD and the optimum timing and method of PTSD assessment have not yet been determined in intensive care unit survivors. Deficiencies in design, methodology and reporting make interpretation and comparison of quoted prevalence rates difficult, and rigorous longitudinal studies are needed.

The organisation and content of trauma memories in survivors of road traffic accidents

We investigated the trauma narratives of 131 road traffic accident survivors prospectively, at 1 week, 6 weeks, and 3 months post-trauma. At 1 and 6 weeks, narratives of survivors with acute stress disorder (ASD) or post-traumatic stress disorder (PTSD) were less coherent and included more dissociation content. By 3 months, their narratives also contained more repetition, more non-consecutive chunks, and more sensory words. Traumatic brain injury was associated with a separate characteristic, confusion, at all three time points. Three aspects of narrative organisation at 1 week--repetition, non-consecutive chunks, and coherence--predicted PTSD severity at 3 months after controlling for initial symptoms. The results suggest both a strong concurrent and predictive relationship between narrative disorganisation and ASD/PTSD but that as people recover from ASD, their narratives do not necessarily become less disorganised.

The relationship of psychological and cognitive factors and opioids in the development of the postconcussion syndrome in general trauma patients with mild traumatic brain injury

The relationship of psychological and cognitive factors in the development of the postconcussion syndrome (PCS) following mild uncomplicated traumatic brain injury (mTBI) has received little study. This may be because of the widely held belief that neurological factors are the cause of early PCS symptoms, whereas psychological factors are responsible for enduring symptoms. To further understand these relationships, the association between PCS and neuropsychological and psychological outcome was investigated in 122 general trauma patients, many of whom had orthopedic injuries, around 5 days following mTBI. Apart from verbal fluency, participants with a PCS did not differ in their performances on neuropsychological measures compared to those without a PCS. Individuals with a PCS reported significantly more psychological symptoms. Large effect sizes present on the psychological measures showed that the difference between participants with a PCS and without was greater on psychological than on neuropsychological measures. Analyses also revealed a relationship between opioid analgesia and depression, anxiety and stress, and opioids and reduced learning. The results suggest that psychological factors are present much earlier than has previously been considered in the development of the PCS.

Low predictive power of peritraumatic dissociation for PTSD symptoms in accident survivors

To test the predictive power of peritraumatic dissociation for the development of psychopathology, the authors assessed symptoms of peritraumatic dissociation (Peritraumatic Dissociative Experiences Questionnaire; PDEQ), posttraumatic stress disorder (Clinician-Administered PTSD Scale; CAPS), anxiety and depression (Hospital Anxiety and Depression Scale; HADS) in a sample of 214 accident victims 5 days postaccident (T1). Six months later (T2), CAPS and HADS were administered again. Acute stress disorder (ASD) and PTSD symptom levels were surprisingly low. In sequential regression analyses, initial reexperiencing and hyperarousal significantly predicted PTSD symptom level (T2) over several possibly confounding variables controlled for. Peritraumatic dissociation explained less than 3% of variance. For PTSD scores, 38% overall variance explanation was obtained; the variance for HADS scores was low. Possible explanations for the low-predictive power of peritraumatic dissociation for posttraumatic psychopathology in the sample are discussed.

Memory of the traumatic event as a risk factor for the development of PTSD: lessons from the study of traumatic brain injury

Traumatic memories, and the mechanisms by which they operate, continue to occupy a central role in the scientific investigation of risk factors for the development of posttraumatic stress disorder (PTSD). However, empirically based studies are constrained by practical and ethical considerations and are limited to naturalistic models. Consequently, the paradigms most appropriate for the exploration of the relationship between traumatic memories and PTSD have been identified in conditions involving traumatic events where memories may be compromised. Indeed, traumatic brain injury, a condition that is commonly associated with memory impairment, has often been utilized as a naturally occurring model for the study of traumatic memory and its contribution to the development of PTSD. This article presents a critical review of these research efforts and discusses their theoretical and clinical implications.