The acute stress response following motor vehicle accidents and its relation to PTSD

Early pharmacological interventions for prevention of post-traumatic stress disorder (PTSD) in individuals experiencing acute traumatic stress symptoms

BACKGROUND

Acute traumatic stress symptoms may develop in people who have been exposed to a traumatic event. Although they are usually self-limiting in time, some people develop post-traumatic stress disorder (PTSD), a severe and debilitating condition. Pharmacological interventions have been proposed for acute symptoms to act as an indicated prevention measure for PTSD development. As many individuals will spontaneously remit, these interventions should balance efficacy and tolerability.

OBJECTIVES

To assess the efficacy and acceptability of early pharmacological interventions for prevention of PTSD in adults experiencing acute traumatic stress symptoms.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Controlled Trial Register (CCMDCTR), CENTRAL, MEDLINE, Embase and two other databases. We checked the reference lists of all included studies and relevant systematic reviews. The search was last updated on 23 January 2023.

SELECTION CRITERIA

We included randomised controlled trials on adults exposed to any kind of traumatic event and presenting acute traumatic stress symptoms, without restriction on their severity. We considered comparisons of any medication with placebo, or with another medication. We excluded trials that investigated medications as an augmentation to psychotherapy.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Using a random-effects model, we analysed dichotomous data as risk ratios (RR) and calculated the number needed to treat for an additional beneficial/harmful outcome (NNTB/NNTH). We analysed continuous data as mean differences (MD) or standardised mean differences (SMD). Our primary outcomes were PTSD severity and dropouts due to adverse events. Secondary outcomes included PTSD rate, functional disability and quality of life.

MAIN RESULTS

We included eight studies that considered four interventions (escitalopram, hydrocortisone, intranasal oxytocin, temazepam) and involved a total of 779 participants. The largest trial contributed 353 participants and the next largest, 120 and 118 participants respectively. The trials enrolled participants admitted to trauma centres or emergency departments. The risk of bias in the included studies was generally low except for attrition rate, which we rated as high-risk. We could meta-analyse data for two comparisons: escitalopram versus placebo (but limited to secondary outcomes) and hydrocortisone versus placebo. One study compared escitalopram to placebo at our primary time point of three months after the traumatic event. There was inconclusive evidence of any difference in terms of PTSD severity (mean difference (MD) on the Clinician-Administered PTSD Scale (CAPS, score range 0 to 136) -11.35, 95% confidence interval (CI) -24.56 to 1.86; 1 study, 23 participants; very low-certainty evidence), dropouts due to adverse events (no participant left the study early due to adverse events; 1 study, 31 participants; very low-certainty evidence) and PTSD rates (RR 0.59, 95% CI 0.03 to 13.08; NNTB 37, 95% CI NNTB 15 to NNTH 1; 1 study, 23 participants; very low-certainty evidence). The study did not assess functional disability or quality of life. Three studies compared hydrocortisone to placebo at our primary time point of three months after the traumatic event. We found inconclusive evidence on whether hydrocortisone was more effective in reducing the severity of PTSD symptoms compared to placebo (MD on CAPS -7.53, 95% CI -25.20 to 10.13; I2 = 85%; 3 studies, 136 participants; very low-certainty evidence) and whether it reduced the risk of developing PTSD (RR 0.47, 95% CI 0.09 to 2.38; NNTB 14, 95% CI NNTB 8 to NNTH 5; I2 = 36%; 3 studies, 136 participants; very low-certainty evidence). Evidence on the risk of dropping out due to adverse events is inconclusive (RR 3.19, 95% CI 0.13 to 75.43; 2 studies, 182 participants; low-certainty evidence) and it is unclear whether hydrocortisone might improve quality of life (MD on the SF-36 (score range 0 to 136, higher is better) 19.70, 95% CI -1.10 to 40.50; 1 study, 43 participants; very low-certainty evidence). No study assessed functional disability.

AUTHORS' CONCLUSIONS

This review provides uncertain evidence regarding the use of escitalopram, hydrocortisone, intranasal oxytocin and temazepam for people with acute stress symptoms. It is therefore unclear whether these pharmacological interventions exert a positive or negative effect in this population. It is important to note that acute traumatic stress symptoms are often limited in time, and that the lack of data prevents the careful assessment of expected benefits against side effects that is therefore required. To yield stronger conclusions regarding both positive and negative outcomes, larger sample sizes are required. A common operational framework of criteria for inclusion and baseline assessment might help in better understanding who, if anyone, benefits from an intervention. As symptom severity alone does not provide the full picture of the impact of exposure to trauma, assessment of quality of life and functional impairment would provide a more comprehensive picture of the effects of the interventions. The assessment and reporting of side effects may facilitate a more comprehensive understanding of tolerability.

What Are the Predictors of Post-traumatic Stress Disorder Among Road Traffic Accident Survivors: A Systematic Review

ABSTRACT

Traffic accidents put tremendous burdens on the psychosocial aspects of communities. Post-traumatic stress disorder (PTSD), after an accident, is one of the most prevalent and incapacitating psychiatric conditions worldwide. In this systematic review, we aimed to investigate the predictors of PTSD in traffic accident victims. Primary search was conducted in November 2021 and updated in 2023. Studies were excluded if they used any analysis except regression for predictors. Cumulatively, primary and update searches retrieved 10,392 articles from databases, and of these, 87 studies were systematically reviewed. The predictors were categorized into sociodemographics, pretrauma, peritrauma, and post-trauma factors. The PTSD assessment time varied between 2 weeks and 3 years. Being a woman, having depression and having a history of road traffic accidents pretraumatically, peritraumatic dissociative experiences, acute stress disorder diagnosis, rumination, higher injury severity, and involvement in litigation or compensation after the trauma were significant predictors of PTSD.

Promoter methylation of the glucocorticoid receptor following trauma may be associated with subsequent development of PTSD

OBJECTIVES

The ability to identify persons at elevated risk for post-traumatic stress disorder (PTSD) soon after exposure to trauma, could aid clinical decision-making and treatment. In this study, we explored whether cytosine methylation of the 1 F promoter of the NR3C1 (glucocorticoid receptor [GR]) gene obtained immediately following a trauma could predict PTSD.

METHODS

Our sample comprised 52 trauma survivors (28 women, 24 men), presenting to the Emergency Department (ED) within six hours of a traumatic event and followed for 13 months. Blood samples were taken at intake (n = 42) and again at the end of the study (13 months later, n = 27) to determine NR3C1-1F promoter methylation as well as plasma levels of cortisol, adrenocorticotropic-hormone (ACTH), and neuropeptide-Y (NPY).

RESULTS

At the 13-month follow-up, participants who met the PTSD criteria (n = 4) showed significantly lower NR3C1-1F promoter sum percent methylation compared to the non-PTSD group (n = 38). Further, NR3C1-1F methylation at ED intake was inversely correlated with PTSD severity 13 months later, indicating that lower NR3C1-1F promoter methylation in the immediate aftermath of trauma was associated with the development of PTSD.

CONCLUSION

To the extent that reduced promoter methylation is associated with greater GR expression and responsivity, this finding is consistent with the hypothalamic-pituitary-adrenal dysregulation previously described for PTSD.

On making (and turning adaptive to) maladaptive aversive memories in laboratory rodents

Fear conditioning and avoidance tasks usually elicit adaptive aversive memories. Traumatic memories are more intense, generalized, inflexible, and resistant to attenuation via extinction- and reconsolidation-based strategies. Inducing and assessing these dysfunctional, maladaptive features in the laboratory are crucial to interrogating posttraumatic stress disorder's neurobiology and exploring innovative treatments. Here we analyze over 350 studies addressing this question in adult rats and mice. There is a growing interest in modeling several qualitative and quantitative memory changes by exposing already stressed animals to freezing- and avoidance-related tests or using a relatively high aversive training magnitude. Other options combine aversive/fearful tasks with post-acquisition or post-retrieval administration of one or more drugs provoking neurochemical or epigenetic alterations reported in the trauma aftermath. It is potentially instructive to integrate these procedures and incorporate the measurement of autonomic and endocrine parameters. Factors to consider when defining the organismic and procedural variables, partially neglected aspects (sex-dependent differences and recent vs. remote data comparison) and suggestions for future research (identifying reliable individual risk and treatment-response predictors) are discussed.

Still Standing Inside: A Local Idiom Related to Trauma among Namibian Speakers of Khoekhoegowab

Euro-centric psychiatric conceptualizations often ignore the interplay of local with universal factors in psychological suffering. Emic, locally focused perspectives can enrich etic knowledge to provide culturally sensitive care and to better elucidate the role of culture in mental illness. This study explored the idiom Tsûsa ǃNaeǃkhais xa hâǃnâ/mâǃnâ/ǂgâǃnâhe hâ (a terrible event has entered a person and remains standing inside), which was understood to relate to experiences of trauma and post-traumatic stress, among speakers of Khoekhoegowab, a southern-African click language. Semi-structured interviews were conducted with 16 participants from six urban and rural communities in Namibia. Questions probed perceptions of the idiom in terms of etiology, course, and risk and resilience factors from a socio-ecological framework. Five key themes were identified using thematic analysis: origin in a shocking event; intrusive recurrence of memories, "it keeps on coming back"; the close interplay between mental and physical suffering; the importance of active engagement in healing through prayer and acceptance; and the role of the community in both alleviating and amplifying distress. Our findings highlight local norms and strategies for adaptive coping, and the benefits of exploring local idioms to elucidate the braiding together of universal and cultural elements in psychological distress.

Acute sleep interventions as an avenue for treatment of trauma-associated disorders

Scientific evidence that acute, posttrauma sleep disturbances (eg, nightmares and insomnia) can contribute significantly to the pathogenesis of trauma-induced disorders is compelling. Sleep disturbances precipitating from trauma are uniquely predictive of daytime posttrauma symptom occurrence and severity, as well as subsequent onset of mental health disorders, including post-traumatic stress disorder. Conversely, adequate sleep during the acute posttrauma period is associated with reduced likelihood of adverse mental health outcomes. These findings, which are broadly consistent with what is known about the role of sleep in the regulation of emotion, suggest that the acute posttrauma period constitutes a "window of opportunity" during which treatment of sleep disturbances may be especially effective for preventing or mitigating progression of aberrant psychophysiological processes. At this point, the weight of the scientific evidence supporting this possibility warrants initiation of clinical trials to confirm the benefits of targeted prophylactic sleep enhancement, and to establish treatment guidelines as appropriate.

CITATION

Swift KM, Thomas CL, Balkin TJ, Lowery-Gionta EG, Matson LM. Acute sleep interventions as an avenue for treatment of trauma-associated disorders. J Clin Sleep Med. 2022;18(9):2291-2312.

Early pharmacological interventions for universal prevention of post-traumatic stress disorder (PTSD)

BACKGROUND

Post-traumatic stress disorder (PTSD) is a severe and debilitating condition. Several pharmacological interventions have been proposed with the aim to prevent or mitigate it. These interventions should balance efficacy and tolerability, given that not all individuals exposed to a traumatic event will develop PTSD. There are different possible approaches to preventing PTSD; universal prevention is aimed at individuals at risk of developing PTSD on the basis of having been exposed to a traumatic event, irrespective of whether they are showing signs of psychological difficulties.

OBJECTIVES

To assess the efficacy and acceptability of pharmacological interventions for universal prevention of PTSD in adults exposed to a traumatic event.

SEARCH METHODS

We searched the Cochrane Common Mental Disorders Controlled Trial Register (CCMDCTR), CENTRAL, MEDLINE, Embase, two other databases and two trials registers (November 2020). We checked the reference lists of all included studies and relevant systematic reviews. The search was last updated on 13 November 2020.

SELECTION CRITERIA

We included randomised clinical trials on adults exposed to any kind of traumatic event. We considered comparisons of any medication with placebo or with another medication. We excluded trials that investigated medications as an augmentation to psychotherapy.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. In a random-effects model, we analysed dichotomous data as risk ratios (RR) and number needed to treat for an additional beneficial/harmful outcome (NNTB/NNTH). We analysed continuous data as mean differences (MD) or standardised mean differences (SMD).

MAIN RESULTS

We included 13 studies which considered eight interventions (hydrocortisone, propranolol, dexamethasone, omega-3 fatty acids, gabapentin, paroxetine, PulmoCare enteral formula, Oxepa enteral formula and 5-hydroxytryptophan) and involved 2023 participants, with a single trial contributing 1244 participants. Eight studies enrolled participants from emergency departments or trauma centres or similar settings. Participants were exposed to a range of both intentional and unintentional traumatic events. Five studies considered participants in the context of intensive care units with traumatic events consisting of severe physical illness. Our concerns about risk of bias in the included studies were mostly due to high attrition and possible selective reporting. We could meta-analyse data for two comparisons: hydrocortisone versus placebo, but limited to secondary outcomes; and propranolol versus placebo. No study compared hydrocortisone to placebo at the primary endpoint of three months after the traumatic event. The evidence on whether propranolol was more effective in reducing the severity of PTSD symptoms compared to placebo at three months after the traumatic event is inconclusive, because of serious risk of bias amongst the included studies, serious inconsistency amongst the studies' results, and very serious imprecision of the estimate of effect (SMD -0.51, 95% confidence interval (CI) -1.61 to 0.59; I² = 83%; 3 studies, 86 participants; very low-certainty evidence). No study provided data on dropout rates due to side effects at three months post-traumatic event. The evidence on whether propranolol was more effective than placebo in reducing the probability of experiencing PTSD at three months after the traumatic event is inconclusive, because of serious risk of bias amongst the included studies, and very serious imprecision of the estimate of effect (RR 0.77, 95% CI 0.31 to 1.92; 3 studies, 88 participants; very low-certainty evidence). No study assessed functional disability or quality of life.  Only one study compared gabapentin to placebo at the primary endpoint of three months after the traumatic event, with inconclusive evidence in terms of both PTSD severity and probability of experiencing PTSD, because of imprecision of the effect estimate, serious risk of bias and serious imprecision (very low-certainty evidence). We found no data on dropout rates due to side effects, functional disability or quality of life. For the remaining comparisons, the available data are inconclusive or missing in terms of PTSD severity reduction and dropout rates due to adverse events. No study assessed functional disability.

AUTHORS' CONCLUSIONS

This review provides uncertain evidence only regarding the use of hydrocortisone, propranolol, dexamethasone, omega-3 fatty acids, gabapentin, paroxetine, PulmoCare formula, Oxepa formula, or 5-hydroxytryptophan as universal PTSD prevention strategies. Future research might benefit from larger samples, better reporting of side effects and inclusion of quality of life and functioning measures.

DHEA Moderates the Impact of Childhood Trauma on the HPA Axis in Adolescence

BACKGROUND

Trauma can lead to long-term downregulation of the hypothalamic pituitary adrenal (HPA) axis. However, dehydroepiandrosterone (DHEA) has neuroprotective effects that may reduce the need for downregulation of the axis in response to stress. Furthermore, high DHEA/cortisol ratios are often conceptualized as better markers of DHEA's availability than DHEA alone, as ratios account for the coupling of DHEA and cortisol in response to stress.

OBJECTIVES

In this study, we explored if DHEA and DHEA/cortisol ratios moderated the association between childhood maltreatment and the HPA axis stress response.

METHODS

The sample consisted of 101 adolescents (ages 12-16) who completed the Child Trauma Questionnaire (CTQ) and the Trier Social Stress Test (TSST). Cortisol was modeled using saliva samples at 8 time points throughout the TSST. Cortisol and DHEA ratios were examined at baseline and 35 min after stress initiation.

RESULTS

Childhood maltreatment was associated with less steep cortisol activation slope and peak cortisol levels, but DHEA and DHEA/cortisol ratios moderated this effect. At high levels of DHEA, the impact of childhood maltreatment on cortisol peak levels was no longer significant. In contrast, high DHEA/cortisol ratios were associated with an intensification of the impact of childhood maltreatment on peak levels.

CONCLUSIONS

Results suggest that DHEA can limit the blunting of the HPA axis in response to childhood maltreatment. However, this protective effect was not reflected in high DHEA/cortisol ratios as predicted. Therefore, high DHEA and high DHEA/cortisol ratios may reflect different, and potentially opposite, processes.

Is PTSD-Phenotype Associated with HPA-Axis Sensitivity? Feedback Inhibition and Other Modulating Factors of Glucocorticoid Signaling Dynamics

Previously, we found that basal corticosterone pulsatility significantly impacts the vulnerability for developing post-traumatic stress disorder (PTSD). Rats that exhibited PTSD-phenotype were characterized by blunted basal corticosterone pulsatility amplitude and a blunted corticosterone response to a stressor. This study sought to identify the mechanisms underlining both the loss of pulsatility and differences in downstream responses. Serial blood samples were collected manually via jugular vein cannula at 10-min intervals to evaluate suppression of corticosterone following methylprednisolone administration. The rats were exposed to predator scent stress (PSS) after 24 h, and behavioral responses were assessed 7 days post-exposure for retrospective classification into behavioral response groups. Brains were harvested for measurements of the glucocorticoid receptor, mineralocorticoid receptor, FK506-binding protein-51 and arginine vasopressin in specific brain regions to assess changes in hypothalamus–pituitary–adrenal axis (HPA) regulating factors. Methylprednisolone produced greater suppression of corticosterone in the PTSD-phenotype group. During the suppression, the PTSD-phenotype rats showed a significantly more pronounced pulsatile activity. In addition, the PTSD-phenotype group showed distinct changes in the ventral and dorsal CA1, dentate gyrus as well as in the paraventricular nucleus and supra-optic nucleus. These results demonstrate a pre-trauma vulnerability state that is characterized by an over-reactivity of the HPA and changes in its regulating factors.

Prior trauma-related experiences predict the development of posttraumatic stress disorder after a new traumatic event

BACKGROUND

Many reports have documented the relationship between previous traumatic experiences, including childhood trauma, and the development of later life psychopathology, including posttraumatic stress disorder (PTSD). Identification of individuals at greatest risk for the development of PTSD could lead to preventative interventions. The present study examined the developmental course of PTSD after trauma exposure, using histories of previous traumatic experiences and the severity of the reaction to the trauma as predictors.

METHODS

Participants (N = 713) were recruited from Emergency Departments in Miami and Atlanta immediately following a traumatic experience. Histories of previous traumatic experiences and the immediate reaction to the new trauma were examined at baseline. Follow-up assessments of PTSD severity were conducted at 1, 3, and 6 months.

RESULTS

Histories of child abuse and pre-existing trauma symptoms predicted the immediate response to stress (R²  = .21, p < .001) and the initial trauma reaction (p < .005).) A mixed-model repeated-measures analysis of variance found that immediate stress response and a history of prior trauma (p < .001) significantly predicted the course of PTSD symptoms. Area under the curve (AUC) analyses suggested that the presence of PTSD at each successive assessment was predicted most substantially by the severity of PTSD at the immediately prior follow-up assessment (AUC > 0.86).

CONCLUSIONS

The current findings suggest that previous traumatic experiences lead to a greater immediate reaction to trauma and combine to predict the development of PTSD, the maintenance of which is not moderated by these earlier experiences. The identification of people likely to develop PTSD may be aided by the assessment of prior experiences and immediate reactions.

PTSD symptoms and cortisol stress reactivity in adolescence: Findings from a high adversity cohort in South Africa

BACKGROUND

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is implicated in the pathophysiology of post-traumatic stress disorder (PTSD). However, there has been little study of HPA stress reactivity in association with PTSD symptoms (PTSS) in children; and there is limited research on PTSD in low and middle-income countries, where trauma exposure is more common and co-occurring stressors more likely.

METHOD

We assessed the relationship between PTSS and cortisol stress reactivity in children aged 13 years (N = 291) from an impoverished South African community. HPA axis stress reactivity was indexed by salivary cortisol during the Trier Social Stress Test (TSST).

RESULTS

In regression analyses both trauma exposure and PTSS showed small inverse associations with total cortisol output (area under the curve with respect to ground) during the TSST, but PTSS effects did not withstand correction for covariates. In addition, hierarchical linear modelling (HLM) found that PTSS were associated with alterations in the shape of the profile of cortisol reactivity that were moderated by sex. In girls, PTSS were associated with reduced linear slope but larger quadratic slopes, whereas the opposite pattern was found in boys. Thus, elevated PTSS were associated with overall blunted profiles of cortisol stress reactivity in girls, but a larger quadratic slope in boys reflects a steeper cortisol increase and decline in boys. There was no relationship between trauma exposure (with or without PTSS) and cortisol reactivity profiles in HLM analyses.

CONCLUSION

In children from a high adversity, low and middle income country context, sex specific associations were found between PTSS and cortisol responses to psychosocial stress. Further research should probe HPA axis functioning more comprehensively in such populations to understand the biological associations of PTSS.

Hypothalamic-pituitary-adrenal axis activity in post-traumatic stress disorder and cocaine use disorder

Post-traumatic stress disorder (PTSD) is often comorbid with cocaine use disorder (CUD), but little is known about hypothalamic-pituitary-adrenal (HPA) axis function in PTSD + CUD. Here we review the clinical and pre-clinical literature of PTSD and CUD with the goal of generating hypotheses about HPA axis activity in comorbid PTSD + CUD. Low glucocorticoid (CORT) levels immediately after trauma exposure are associated with PTSD. CORT administered within 12 h of trauma exposure reduces later PTSD symptoms. Weeks-years after trauma, meta-analyses find lower CORT levels in patients with PTSD relative to never-traumatized controls; the same is found in a pre-clinical model of PTSD. In rodents, reduced basal CORT levels are consistently found after chronic cocaine self-administration. Conversely, increased CORT levels are found in CUD patients during the first 2 weeks of cocaine abstinence. There is evidence for CORT hyper-suppression after dexamethasone, high glucocorticoid receptor (GR) number pre-trauma, and increased GR translocation to the nucleus in PTSD. Hyper-suppression of HPA axis activity after dexamethasone suggests that PTSD individuals may have increased anterior pituitary GR. Given evidence for decreased anterior pituitary GR in rats that self-administer cocaine, PTSD + CUD individuals may have normal GR density and low basal CORT levels during late abstinence. Future studies should aim to reconcile the differences in pre-clinical and clinical basal CORT levels during cocaine and assess HPA axis function in both rodent models of CUD that consider stress-susceptibility and in PTSD + CUD individuals. Although additional studies are necessary, individuals with PTSD + CUD may benefit from behavioral and psychopharmacological treatments to normalize HPA axis activity. LAY SUMMARY Post-traumatic stress disorder (PTSD) is often comorbid with cocaine use disorder (CUD), but little is known about the hypothalamic-pituitary-adrenal (HPA) axis function in PTSD + CUD. The current review provides a synthesis of available clinical and pre-clinical data on PTSD and CUD with the goal of generating hypotheses about HPA axis activity in comorbid PTSD + CUD. While this review finds ample evidence supporting aberrant HPA axis activity in both PTSD and CUD, it suggests that more research is needed to understand the unique changes HPA axis activity in PTSD + CUD, as well as the bidirectional relationship between stress-susceptibility and motivation to seek cocaine.

Early posttraumatic autonomic and endocrine markers to predict posttraumatic stress symptoms after a preventive intervention with oxytocin

BACKGROUND

Efficient prevention of posttraumatic stress disorder (PTSD) needs to target individuals with an increased risk for adverse outcome after trauma. Prognostic or prescriptive biological markers assessed early posttrauma may inform personalized treatment recommendations.

OBJECTIVE

To test prognostic and prescriptive effects of early (posttraumatic) autonomic and endocrine markers on PTSD symptom development.

METHOD

Autonomic and endocrine markers were assessed within 12 days posttrauma and before treatment initiation within a randomized placebo-controlled trial investigating repeated oxytocin administration as preventive intervention for PTSD. Linear mixed effects models were used to test the effects of heart rate (variability), resting cortisol, morning cortisol and cortisol awakening response (CAR), cortisol suppression by dexamethasone and resting oxytocin on PTSD symptoms 1.5, 3 and 6 months posttrauma in men (n = 54), women using hormonal contraception (n = 27) and cycling women (n = 19).

RESULTS

We found significant prognostic effects of resting oxytocin and cortisol suppression. In women using hormonal contraception, higher oxytocin was associated with higher PTSD symptoms across follow-up. Stronger cortisol suppression by dexamethasone, reflecting increased glucocorticoid receptor feedback sensitivity, was associated with lower PTSD symptoms across follow-up in men, but with higher symptoms at 1.5 months in women using hormonal contraception. These effects were independent of treatment condition. No further significant prognostic or prescriptive effects were detected.

CONCLUSION

Our exploratory study indicates that resting oxytocin and glucocorticoid receptor feedback sensitivity early posttrauma are associated with subsequent PTSD symptom severity. Notably, prognostic effects depended on sex and hormonal contraception use, emphasizing the necessity to consider these factors in biomedical PTSD research.

Dietary contributions to increased background lead, mercury, and cadmium in 9-11 Year old children: Accounting for racial differences

BACKGROUND

Initial interest in the adverse consequences of exposure to lead (Pb), mercury (Hg), and cadmium (Cd) focused on relatively high exposures through environmental or occupational sources; however, recent evidence suggests even low-level background exposure to non-essential metals might be detrimental, particularly for children's health and development. One potentially important source of increased background levels of non-essential toxic metals is diet.

OBJECTIVES

We considered whether differences in diet are associated with levels of non-essential metals in blood and whether racial differences in metals are mediated by dietary differences.

METHODS

We assessed blood levels of Pb, Hg, and Cd in a sample of 9-11 year-old children (N = 295) comprised of 42% European Americans (EAs), 58% African American (AAs), and 47% female. Diet was assessed using 24-h dietary recalls during phone interviews administered to parents on two consecutive days (Friday and Saturday). The Healthy Eating Index-2105 (HEI-2015) was calculated to assess diet quality.

RESULTS

The current study identified significant dietary sources of non-essential metal exposure - namely total fruit for Pb, total protein for Hg, and greens and beans for Cd. Moreover, AAs were found to have significantly higher blood levels of Pb and Hg than EAs and these racial differences were significantly mediated by these dietary differences.

DISCUSSION

This study is one of very few to consider total diet in children and exposure to the non-essential metals Pb, Hg, and Cd, and the first to demonstrate that racial differences in increased background blood levels of non-essential toxic metals can be accounted for by racial differences in diet. Given regional differences in food consumption patterns and specific farm and store sources for the foods, the generalizability of the current findings has yet to be determined; however, commonly consumed foods appear to be a significant source of low-level non-essential metals.

Rethinking post-traumatic stress disorder - A predictive processing perspective

Predictive processing has become a popular framework in neuroscience and computational psychiatry, where it has provided a new understanding of various mental disorders. Here, we apply the predictive processing account to post-traumatic stress disorder (PTSD). We argue that the experience of a traumatic event in Bayesian terms can be understood as a perceptual hypothesis that is subsequently given a very high a-priori likelihood due to its (life-) threatening significance; thus, this hypothesis is re-selected although it does not fit the actual sensory input. Based on this account, we re-conceptualise the symptom clusters of PTSD through the lens of a predictive processing model. We particularly focus on re-experiencing symptoms as the hallmark symptoms of PTSD, and discuss the occurrence of flashbacks in terms of perceptual and interoceptive inference. This account provides not only a new understanding of the clinical profile of PTSD, but also a unifying framework for the corresponding pathologies at the neurobiological level. Finally, we derive directions for future research and discuss implications for psychological and pharmacological interventions.

Cannabinoids as therapeutics for PTSD

Post-traumatic stress disorder (PTSD) is a complex disorder that involves dysregulation of multiple neurobiological systems. The traumatic stressor plays a causal role in producing psychological dysfunction and the pattern of findings suggests that the hypothalamic-pituitary-adrenal (HPA) axis, which is instrumental for stress adaptation, is critically dysfunctional in PTSD. Given the lack of understanding of the basic mechanisms and underlying pathways that cause the disorder and its heterogeneity, PTSD poses challenges for treatment. Targeting the endocannabinoid (ECB) system to treat mental disorders, and PTSD in particular, has been the focus of research and interest in recent years. The ECB system modulates multiple functions, and drugs enhancing ECB signaling have shown promise as potential therapeutic agents in stress effects and other psychiatric and medical conditions. In this review, we focus on the interaction between the ECB-HPA systems in animal models for PTSD and in patients with PTSD. We summarize evidence supporting the use of cannabinoids in preventing and treating PTSD in preclinical and clinical studies. As the HPA system plays a key role in the mediation of the stress response and the pathophysiology of PTSD, we describe preclinical studies suggesting that enhancing ECB signaling is consistent with decreasing PTSD symptoms and dysfunction of the HPA axis. Overall, we suggest that a pharmacological treatment targeted at one system (e.g., HPA) may not be very effective because of the heterogeneity of the disorder. There are abnormalities across different neurotransmitter systems in the pathophysiology of PTSD and none of these systems function uniformly among all patients with PTSD. Hence, conceptually, enhancing ECB signaling may be a more effective avenue for pharmacological treatment.

Pharmacological prevention and early treatment of post-traumatic stress disorder and acute stress disorder: a systematic review and meta-analysis

Post-traumatic stress disorder (PTSD) is a common mental disorder associated with significant distress and reduced functioning. Its occurrence after a severe traumatic event and association with characteristic neurobiological changes make PTSD a good candidate for pharmacological prevention and early treatment. The primary aim for this systematic review and meta-analysis was to assess whether pharmacological interventions when compared to placebo, or other pharmacological/psychosocial interventions resulted in a clinically significant reduction or prevention of symptoms, improved functioning or quality of life, presence of disorder, or adverse effects. A systematic search was undertaken to identify RCTs, which used early pharmacotherapy (within three months of a traumatic event) to prevent and treat PTSD and acute stress disorder (ASD) in children and adults. Using Cochrane Collaboration methodology, RCTs were identified and rated for risk of bias. Available data was pooled to calculate risk ratios (RR) for PTSD prevalence and standardised mean differences (SMD) for PTSD severity. 19 RCTs met the inclusion criteria; 16 studies with adult participants and three with children. The methodological quality of most trials was low. Only hydrocortisone in adults was found to be superior to placebo (3 studies, n = 88, RR: 0.21 (CI 0.05 to 0.89)) although this was in populations with severe physical illness, raising concerns about generalisability. No significant effects were found for the other pharmacotherapies investigated (propranolol, oxytocin, gabapentin, fish oil (1470 mg DHA/147 mg EPA), fish oil (224 mg DHA/22.4 mg EPA), dexamethasone, escitalopram, imipramine and chloral hydrate). Hydrocortisone shows the most promise, of pharmacotherapies subjected to RCTs, as an emerging intervention in the prevention of PTSD within three months after trauma and should be a target for further investigation. The limited evidence for hydrocortisone and its adverse effects mean it cannot be recommended for routine use, but, it could be considered as a preventative intervention for people with severe physical illness or injury, shortly after a traumatic event, as long as there are no contraindications. More research is needed using larger, high quality RCTs to establish the most efficacious use of hydrocortisone in different populations and optimal dosing, dosing window and route. There is currently a lack of evidence to suggest that other pharmacological agents are likely to be effective.

A pilot study on salivary cortisol secretion and auditory P300 event-related potential in patients with physical disability-related stress

Objective: To evaluate the stress level and attention in workers with physical disabilities-related stress.Methods: Morning salivary cortisol was used as a stress marker while the event-related potential during the performance of the auditory oddball paradigm was conducted to investigate the attentive ability to sound stimuli. Eighteen injured workers (IP) and eighteen unaffected healthy adults (CP) were recruited for this study with half being men and the other half women (aged 21-55). Behavioral performance measures including reaction time (RT), accuracy rate, and commission error as well as the latency and amplitude of P300 wave over the central (Cz), centroparietal (CPz), and parietal (Pz) electroencephalogram electrode sites were used to compare the two groups.Results: This study demonstrated significantly higher salivary cortisol levels, longer RT, less accuracy to respond to the target during the auditory oddball paradigm in the IP group as compared to CP group. In addition, a significant prolongation of the peak latency of auditory P300 wave over CPz electrodes was also detected in IP group.Conclusion: The increased cortisol levels found in the IP group reflect the alteration of the basal hypothalamic-pituitary-adrenal axis as a result of the stresses of living with a physical disability. Delayed RT and the decreased in accuracy together with changing in peak latencies of auditory P300 wave indicate the impairment of attention networks in IP. Our study revealed that the patients with permanent physical disability.

Glucocorticoids and Hippocampal Structure and Function in PTSD

This review examines the putative link between glucocorticoid and hippocampal abnormalities in posttraumatic stress disorder (PTSD). Increased glucocorticoid receptor (GR) sensitivity in PTSD may permit enhanced negative feedback inhibition of cortisol at the pituitary, hypothalamus, or other brain regions comprising the hypothalamic-pituitary-adrenal (HPA) axis and would be expected to affect other physiological systems that are regulated by glucocorticoids. Molecular and transcriptional studies of cortisol are consistent with the hypothesis that cortisol actions may be amplified in PTSD as a result of enhanced GR sensitivity in monocytes and some brain regions, although cortisol levels themselves are unchanged and oftentimes lower than normal. Concurrently, magnetic resonance imaging studies have demonstrated that individuals with PTSD have smaller hippocampal volume than individuals without PTSD. Initial hypotheses regarding the mechanism underlying hippocampal alterations in PTSD focused on elevated glucocorticoid levels in combination with extreme stress as the primary cause, but this explanation has not been well supported in human studies. Lack of data from neuroimaging studies preclude a firm link between PTSD onset and hippocampal volume changes. Rather, the available evidence is consistent with the possibility that smaller hippocampal volume (like reduced cortisol levels and enhanced GR sensitivity) may be a vulnerability factor for developing the disorder; limitations of hippocampal-based models of PTSD are described. We further review neuroimaging studies examining hippocampal structure and function following manipulation of glucocorticoid levels and also examining changes in the hippocampus in relationship to other brain regions. Evidence that the GR may be an important therapeutic target for the treatment of PTSD, especially for functions subserved by the hippocampus, is discussed. Implications of the current review for future research are described, with an emphasis on the need to integrate findings of glucocorticoid abnormalities with functional-imaging paradigms to formulate a comprehensive model of HPA-axis functioning in PTSD.

The hypothalamic-pituitary-adrenal axis in PTSD: Pathophysiology and treatment interventions

Questions of how altered functioning of the hypothalamic pituitary adrenal (HPA) axis contribute to the development and maintenance of posttraumatic stress disorder (PTSD) have been the focus of extensive animal and human research. As a rule, results have been inconsistent across studies, likely due to a variety of confounding variables that have received inadequate attention. Important confounding factors include the effects of early life stress, biological sex, and the glucocorticoid used for interventions. In this manuscript we review: 1) the literature on identified abnormalities of HPA axis function in PTSD, both in terms of basal functioning and as part of challenge paradigms; 2) the role of HPA axis function pre- and immediately post-trauma as a risk factor for PTSD development; 3) the impact of HPA axis genes' allelic variants and epigenetic modifications on PTSD risk; 4) the contributions of HPA axis components to fear learning and extinction; and 5) therapeutic manipulations of the HPA axis to both prevent and treat PTSD, including the role of glucocorticoids as part of medication enhanced psychotherapy.

Hormone Therapy in Trauma Patients

Low-dose hydrocortisone reduces the dose of vasopressors and hospital length of stay; it may also decrease the rate of hospital-acquired pneumonia and time on ventilator. No major side effect was reported, but glycemia and natremia should be monitored. Progesterone did not enhance outcome of trauma patients. A meta-analysis suggested that oxandrolone was associated with shorter length of stay and reduced weight loss. Erythropoietin did not enhance neurologic outcome of traumatic brain-injured patients; such treatment, however, could reduce the mortality in subgroups of patients. This review focuses mainly on glucocorticoids, which are the most extensively investigated treatments in hormone therapy.

Meta-analytic connections between forgiveness and health: the moderating effects of forgiveness-related distinctions

OBJECTIVE

We explore meta-analytic associations between health and forgiveness, testing a number of potential theoretical and methodological factors that could alter that association, including the type of forgiveness measure (e.g. state vs. trait), the type of health measure (i.e. physical vs. psychological) and the target of forgiveness (e.g. self- vs. other-forgiveness).

DESIGN

Our findings below reflect the meta-analysis of 103 independent samples consisting of 606 correlations with a total sample of 26,043 participants. The final sample included papers from 17 countries. The included samples were diverse including students, older adults, divorced mothers, combat veterans and others.

MAIN OUTCOME MEASURES

Various health measures, including physical health outcomes (e.g., blood pressure, cortisol levels, bodily pain) and psychological health outcomes (e.g., depression, anxiety, PTSD).

RESULTS

We found a reliable overall association between forgiveness and health outcomes. The association was stronger for psychological health than for physical health, though associations with cardiovascular health indicators (i.e. heart-rate and blood pressure) were robust.

CONCLUSION

The findings provided considerable support to current theorizing about the health benefits of forgiveness. It is plausible that forgiveness might improve psychological health and reduce cardiovascular stress.

Developmental influences on stress response systems: Implications for psychopathology vulnerability in adolescence

The adolescent transition is marked by increases in stress exposure and significant maturation of neural and hormonal stress processing systems. Variability in the development of these systems during adolescence may influence the risk for stress-related psychopathology. This paper aims to review the developmental maturation of the HPA axis and related stress regulation systems, and demonstrate how interference in this adaptive developmental process may increase the risk for negative outcomes. We argue that the developmental maturation of the HPA axis aims to improve the regulatory capacity of the axis in order to more adaptively respond to these increases in stress reactivity. Additionally, we review evidence that sex differences in the development of the HPA and related axes may contribute to sex differences in the risk for stress-related psychopathology. Finally, we discuss how contextual factors, such as early trauma and obesity may alter the development of HPA axis during the adolescence transition and how alterations of normative development increase the risk for stress-related disorders.

Glucocorticoid-induced enhancement of extinction-from animal models to clinical trials

Extensive evidence from both animal model and human research indicates that glucocorticoid hormones are crucially involved in modulating memory performance. Glucocorticoids, which are released during stressful or emotionally arousing experiences, enhance the consolidation of new memories, including extinction memory, but reduce the retrieval of previously stored memories. These memory-modulating properties of glucocorticoids have recently received considerable interest for translational purposes because strong aversive memories lie at the core of several fear-related disorders, including post-traumatic stress disorder and phobias. Moreover, exposure-based psychological treatment of these disorders relies on successful fear extinction. In this review, we argue that glucocorticoid-based interventions facilitate fear extinction by reducing the retrieval of aversive memories and enhancing the consolidation of extinction memories. Several clinical trials have already indicated that glucocorticoids might be indeed helpful in the treatment of fear-related disorders.

Inflammation as a predictor of disease course in posttraumatic stress disorder and depression: A prospective analysis from the Mind Your Heart Study

BACKGROUND

Prior research has focused largely on the pro-inflammatory states of PTSD and depression, with few studies evaluating the direction of inflammation's association with these disorders. To clarify whether inflammation plays a role in the development of PTSD or depression, we assessed the predictive value of inflammatory biomarkers on the courses of these conditions in a cohort of Veterans.

METHODS

This research was part of the Mind Your Heart Study, a prospective cohort study designed to examine PTSD-related health outcomes. Between 2008 and 2010, 746 San Francisco area Veterans Administration patients were enrolled. At baseline, inflammatory biomarkers were measured from fasting morning venous blood draws, and cortisol and catecholamine levels were measured from 24-hour urine samples. PTSD was diagnosed using the PTSD Checklist at baseline and annual follow-up. Depression was evaluated using the 9-item Patient Health Questionnaire at baseline and follow-up. Ordinal logistic regression models were used to assess the predictive value of baseline biomarker levels on clinically relevant courses of PTSD and depression categorized and ordered as none, resolved, developed, and chronic.

RESULTS

After adjustment for age and sex, elevated levels of white blood cell count (OR = 1.27(1.10-1.47), p = 0.001), C-reactive protein (OR = 1.20(1.04-1.39), p = 0.02), fibrinogen (OR = 1.19(1.03-1.38), p = 0.02), and ESR (OR = 1.17(1.00-1.36, p = 0.05), and decreased levels of urine cortisol (OR = 0.84(0.71-0.99), p = 0.04) were significant predictors of poorer courses of PTSD. Elevated levels of WBC count (OR = 1.31(1.14-1.50), p < 0.001), CRP (OR = 1.24(1.07-1.43), p = 0.003), fibrinogen (OR = 1.26(1.09-1.46), p = 0.002), and catecholamines (OR = 1.17(1.01-1.36), p = 0.04) were significant predictors of poorer courses of depression. After additionally controlling for physical activity, elevated WBC count (p = 0.002) and decreased levels of urine cortisol (p = 0.05) remained significant predictors of PTSD course, and elevated WBC count (p = 0.001), CRP (p = 0.03), and fibrinogen (p = 0.02) remained significant predictors of depression course. After adjusting for all significant variables, elevated WBC count (p = 0.02) was a significant predictor of a poorer course of PTSD, and elevated WBC count (p = 0.04) and platelet count (p = 0.03) were significant predictors of a poorer course of depression.

CONCLUSIONS

Increased levels of several inflammatory biomarkers were associated with significantly increased odds of clinically worse courses of PTSD and depression. Inflammation may be a target for prevention and treatment of these mental health disorders.

Increased cognitive control and reduced emotional interference is associated with reduced PTSD symptom severity in a trauma-exposed sample: A preliminary longitudinal study

Individuals with posttraumatic stress disorder (PTSD) show deficits in recruiting neural regions associated with cognitive control. In contrast, trauma exposed individuals (TEIs) show increased recruitment of these regions. While many individuals who experience a trauma exhibit some PTSD symptoms, relatively few develop PTSD. Despite this, no work has examined the relationship between changes in PTSD symptoms and changes in neural functioning in TEIs longitudinally. This study examined the neural correlates of changing PTSD symptom levels in TEIs. Twenty-one military service members completed the affective stroop task while undergoing fMRI within 2 months of returning from deployment and a second scan 6-12 months later. Participants with PTSD or depression at baseline were excluded. PTSD symptom improvement was associated with greater increase in response to incongruent relative to congruent negative stimuli in dorsal anterior cingulate cortex and inferior frontal gyrus/anterior insula and increased BOLD response over time to emotional relative to neutral stimuli in inferior parietal cortex. Improvement in PTSD symptoms were not associated with changes in amygdala responsiveness to emotional stimuli. In short, the current data indicate that TEIs who become more able to recruit regions implicated in cognitive control show greater reductions in PTSD symptom levels.

Childhood Emotional Abuse Moderates Associations Among Corticomotor White Matter Structure and Stress Neuromodulators in Women With and Without Depression

Adverse caregiving during development can produce long-lasting changes to neural, endocrine, and behavioral responses to stress, and is strongly related to elevated risk of adult psychopathology. While prior experience of adversity is associated with altered sympathetic nervous system (SNS) and hypothalamic-pituitary-adrenal (HPA) axis activity, the underlying neural pathways are not completely understood. In a double-blind crossover study, we used diffusion tensor imaging (DTI) to examine whether variation in white matter structure predicts differences in HPA-SNS interactions as a function of early adversity. Participants included 74 women who exhibited a wide range of depression severity and/or childhood emotional abuse (EA). Participants attended two experimental sessions during which they were administered 20 mg cortisol (CORT) or placebo and after 90 min, viewed emotionally laden pictures while undergoing MRI scanning. Immediately after emotional picture-viewing, we collected salivary alpha-amylase (sAA) to index SNS activation. We tested whether EA moderated the relation between fractional anisotropy (FA), a measure of white matter fiber structure, and sAA. In the placebo condition, for participants with minimal history of EA, higher FA in corticomotor projections was negatively correlated with sAA, whereas in participants with severe EA, the correlation was trending in the opposite direction. Following CORT administration, FA and sAA were not related, suggesting that SNS tone during acute cortisol elevation may depend on neural pathways other than corticomotor projections. The results suggest that at baseline—though not during cortisol elevation—increased FA in these tracts is associated with lower levels of SNS activity in women with minimal EA, but not in women with severe EA. These findings provide evidence that corticomotor projections may be a key component of altered neural circuitry in adults with history of maltreatment, and may be related to alterations in stress neuromodulators in psychopathology.

Epigenetic programming of the neuroendocrine stress response by adult life stress

The hypothalamic-pituitary-adrenal (HPA) axis is critically involved in the neuroendocrine regulation of stress adaptation, and the restoration of homeostasis following stress exposure. Dysregulation of this axis is associated with stress-related pathologies like major depressive disorder, post-traumatic stress disorder, panic disorder and chronic anxiety. It has long been understood that stress during early life can have a significant lasting influence on the development of the neuroendocrine system and its neural regulators, partially by modifying epigenetic regulation of gene expression, with implications for health and well-being in later life. Evidence is accumulating that epigenetic plasticity also extends to adulthood, proposing it as a mechanism by which psychological trauma later in life can long-lastingly affect HPA axis function, brain plasticity, neuronal function and behavioural adaptation to neuropsychological stress. Further corroborating this claim is the phenomenon that these epigenetic changes correlate with the behavioural consequences of trauma exposure. Thereby, epigenetic modifications provide a putative molecular mechanism by which the behavioural phenotype and transcriptional/translational potential of genes involved in HPA axis regulation can change drastically in response to environmental challenges, and appear an important target for treatment of stress-related disorders. However, improved insight is required to increase their therapeutic (drug) potential. Here, we provide an overview of the growing body of literature describing the epigenetic modulation of the (primarily neuroendocrine) stress response as a consequence of adult life stress and interpret the implications for, and the challenges involved in applying this knowledge to, the identification and treatment of stress-related psychiatric disorders.

Dual-hormone stress reactivity predicts downstream war-zone stress-evoked PTSD

BACKGROUND

The crucial role of the hypothalamic-pituitary-adrenal axis (HPA) in stress-related homeostasis suggests dysregulated HPA involvement in the pathogenesis of post-traumatic stress disorder (PTSD), yet most studies examining linkages between HPA axis measures and PTSD have yielded null findings. One untested explanation for this inconsistency is a failure to account for simultaneous adrenal and gonadal influence. Here we tested the singular and interactive effects of cortisol (C_R) and testosterone (T_R) reactivity as moderators of war-zone stress evoked PTSD emergence in the war-zone.

METHODS

U.S. soldiers (N=120) scheduled for deployment to Iraq completed pre-deployment measures of C_R and T_R stress reactivity to a CO₂ inhalation challenge. Once deployed, monthly assessments of exposure to traumatic war-zone stressors and PTSD symptoms were collected via a web-based assessment system.

RESULTS

Cortisol hypo-reactivity potentiated the pathogenic impact of war-zone stressors only in soldiers for whom the CO₂ challenge did not elevate testosterone, suggesting that the dual hormone stress reactivity profile of blunted cortisol and testosterone may confer increased risk for PTSD emergence by potentiating the pathogenic effects of war-zone stressors.

CONCLUSIONS

Findings underscore the utility of assessing both HPA and HPG stress reactivity when assessing PTSD vulnerability and may help inform efforts for enhanced soldier screening and inoculation to war-zone stressors.

Post-traumatic stress disorder dimensions and asthma morbidity in World Trade Center rescue and recovery workers

OBJECTIVE

Using data from a cohort of World Trade Center (WTC) rescue and recovery workers with asthma, we assessed whether meeting criteria for post-traumatic stress disorder (PTSD), sub-threshold PTSD, and for specific PTSD symptom dimensions are associated with increased asthma morbidity.

METHODS

Participants underwent a Structured Clinical Interview for Diagnostic and Statistical Manual to assess the presence of PTSD following DSM-IV criteria during in-person interviews between December 2013 and April 2015. We defined sub-threshold PTSD as meeting criteria for two of three symptom dimensions: re-experiencing, avoidance, or hyper-arousal. Asthma control, acute asthma-related healthcare utilization, and asthma-related quality of life data were collected using validated scales. Unadjusted and multiple regression analyses were performed to assess the relationship between sub-threshold PTSD and PTSD symptom domains with asthma morbidity measures.

RESULTS

Of the 181 WTC workers with asthma recruited into the study, 28% had PTSD and 25% had sub-threshold PTSD. Patients with PTSD showed worse asthma control, higher rates of inpatient healthcare utilization, and poorer asthma quality of life than those with sub-threshold or no PTSD. After adjusting for potential confounders, among patients not meeting the criteria for full PTSD, those presenting symptoms of re-experiencing exhibited poorer quality of life (p = 0.003). Avoidance was associated with increased acute healthcare use (p = 0.05). Sub-threshold PTSD was not associated with asthma morbidity (p > 0.05 for all comparisons).

CONCLUSIONS

There may be benefit in assessing asthma control in patients with sub-threshold PTSD symptoms as well as those with full PTSD to more effectively identify ongoing asthma symptoms and target management strategies.

Stress, glucocorticoids and memory: implications for treating fear-related disorders

Glucocorticoid stress hormones are crucially involved in modulating mnemonic processing of emotionally arousing experiences. They enhance the consolidation of new memories, including those that extinguish older memories, but impair the retrieval of information stored in long-term memory. As strong aversive memories lie at the core of several fear-related disorders, including post-traumatic stress disorder and phobias, the memory-modulating properties of glucocorticoids have recently become of considerable translational interest. Clinical trials have provided the first evidence that glucocorticoid-based pharmacotherapies aimed at attenuating aversive memories might be helpful in the treatment of fear-related disorders. Here, we review important advances in the understanding of how glucocorticoids mediate stress effects on memory processes, and discuss the translational potential of these new conceptual insights.

The centrality of fear extinction in linking risk factors to PTSD: A narrative review

Recent prospective studies in emergency services have identified impaired fear extinction learning and memory to be a significant predictor of Posttraumatic Stress Disorder (PTSD), complementing a wealth of cross-sectional evidence of extinction deficits associated with the disorder. Additional fields of research show specific risk factors and biomarkers of the disorder, including candidate genotypes, stress and sex hormones, cognitive factors, and sleep disturbances. Studies in mostly nonclinical populations also reveal that the aforementioned factors are involved in fear extinction learning and memory. Here, we provide a comprehensive narrative review of the literature linking PTSD to these risk factors, and linking these risk factors to impaired fear extinction. On balance, the evidence suggests that fear extinction may play a role in the relationship between risk factors and PTSD. Should this notion hold true, this review carries important implications for the improvement of exposure-based treatments, as well as strategies for the implementation of treatment.

Acute stress disorder as a predictor of posttraumatic stress: A longitudinal study of Chinese children exposed to the Lushan earthquake

This study examined the prevalence of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) in children who experienced the Lushan earthquake in Sichuan, China, and assessed the ability of ASD to predict PTSD. The Acute Stress Disorder Scale (ASDS) was used to assess acute stress reaction within weeks of the trauma. The University of California at Los Angeles Post-Traumatic Stress Disorder Reaction Index (UCLA-PTSD) for children was administered at intervals of 2, 6, and 12 months after the earthquake to 197 students who experienced the Lushan earthquake at the Longxing Middle School. The results demonstrated that 28.4% of the children suffered from ASD, but only a small percentage of the population went on to develop PTSD. Among all of the students, 35.0% of those who met the criteria for ASD were diagnosed with PTSD at the 12-month interval. The severity of ASD symptoms correlated with later PTSD symptoms.

Prevention of Trauma and Stressor-Related Disorders: A Review

Posttraumatic stress disorder (PTSD) is a common, frequently chronic, and disabling condition which, along with acute stress disorder (ASD), is categorized as a trauma- and stressor-related disorder by the DSM-5. These disorders are unique in requiring exposure to a severe stressor, which implies that potential sufferers could be identified and helped before developing a disorder. Research on prevention strategies for stress-related disorders has taken a number of avenues, including intervention before and after trauma and the use of both psychosocial and somatic approaches. Despite advances in neurobiological understanding of response to trauma, clinical evidence for preventive interventions remains sparse. This review provides an overview of prevention approaches and summarizes the existing literature on prevention of ASD and PTSD, including clinical and preclinical studies. Given the potential benefits to trauma survivors and society, the development of effective preventive interventions should be given greater priority. Resources should be directed to adequately test promising interventions in clinical trials, and research should be conducted according to translational research principles in which preclinical research informs the design of clinical studies.

The role of early pharmacotherapy in the development of posttraumatic stress disorder symptoms after traumatic injury: an observational cohort study in consecutive patients

OBJECTIVE

Pharmacological intervention during traumatic memory consolidation has been suggested to prevent posttraumatic stress disorder (PTSD). The aim of this study was to examine the association between prescription of early pharmacotherapy and the risk of developing PTSD symptoms following traumatic injury.

METHOD

The use of opiate analgesics, beta-adrenergic blockers, corticosteroids and benzodiazepines within 48 h postinjury was documented based on hospital charts for 629 Level 1 trauma center patients. PTSD symptoms were assessed using structured clinical interviews. Primary outcome was 6-week PTSD symptoms. Secondary outcomes were PTSD diagnoses at 6 weeks and during 1 year posttrauma.

RESULTS

Linear regression analyses showed that opiate administration within 48 h was negatively associated with PTSD symptoms at 6 weeks (β=-0.14, P=.009) after controlling for demographic and injury-related characteristics and concurrent pharmacotherapy. Fewer patients with opiates had a PTSD diagnosis at 6 weeks (P=.047) and during 1 year posttrauma (P=.013) than patients with none of the specified pharmacotherapies. Low prescription frequency of beta-blockers (3.8%), corticosteroids (2.2%) and benzodiazepines (7.8%) precluded further examination of their role in the development of PTSD symptoms because of limited statistical power.

CONCLUSIONS

This study suggests a possible beneficial influence of opiate administration within 48 h posttrauma on the development of PTSD symptoms. Future studies may evaluate the effectiveness of inhospital opiate analgesics compared to placebo in preventing PTSD and may focus on the mechanisms underlying the effect of opiates in preventing PTSD.

Post-training corticosterone inhibits the return of fear evoked by platform stress and a subthreshold conditioning procedure in Sprague-Dawley rats

The return of fear is an important issue in anxiety disorder research. Each time a fear memory is reactivated, it may further strengthen overactivation of the fear circuit, which may contribute to long-term maintenance of the fear memory. Recent evidence indicates that glucocorticoids may help attenuate pathological fear, but its role in the return of fear is unclear. In the present study, systemic corticosterone (CORT; 25mg/kg) administration 1h after fear conditioning did not impair the consolidation process but significantly suppressed the return of fear evoked by a subthreshold conditioning (SC) procedure and elevated platform (EP) stress. Compared with the SC-induced return of fear, acute stress-induced return was state-dependent. In addition, post-training CORT treatment increased the adrenocorticotropic response after EP stress, which indicates that the drug-induced suppression of the return of fear may possibly derive from its regulation effect of the hypothalamic-pituitary-adrenal axis reactivity to stress. These results suggest that post-training CORT administration may help inhibit the return of fear evoked by EP or SC stress. The possible mechanisms involved in the high-dose CORT-induced suppression of the SC- and EP-induced return of fear are discussed.

Diurnal fluctuations in HPA and neuropeptide Y-ergic systems underlie differences in vulnerability to traumatic stress responses at different zeitgeber times

The hypothalamic-pituitary-adrenal (HPA) axis displays a characteristic circadian pattern of corticosterone release, with higher levels at the onset of the active phase and lower levels at the onset of the inactive phase. As corticosterone levels modify the response to stress and influence the susceptibility to and/or severity of stress-related sequelae, we examined the effects of an acute psychological trauma applied at different zeitgeber times (ZTs) on behavioral stress responses. Rats were exposed to stress either at the onset of the inactive-(light) phase (ZT=0) or at the onset of the active-(dark) phase (ZT=12). Their behavior in the elevated plus-maze and acoustic startle response paradigms were assessed 7 days post exposure for retrospective classification into behavioral response groups. Serum corticosterone levels and the dexamethasone suppression test were used to assess the stress response and feedback inhibition of the HPA axis. Immunoreactivity for neuropeptide Y (NPY) and NPY-Y1 receptor (Y1R) in the paraventricular (PVN) and arcuate (ARC) hypothalamic nuclei, hippocampus, and basolateral amygdala were measured. The behavioral effects of NPY/Y1R antagonist microinfused into the PVN 30 min before stress exposure during the inactive or active phase, respectively, were evaluated. PVN immunoreactivity for NPY and Y1R was measured 1 day after the behavioral tests. The time of day of the traumatic exposure markedly affected the pattern of the behavioral stress response and the prevalence of rats showing an extreme behavioral response. Rats exposed to the stressor at the onset of their inactive phase displayed a more traumatic behavioral response, faster post-exposure corticosterone decay, and a more pronounced stress-induced decline in NPY and Y1R expression in the PVN and arcuate hypothalamic nuclei. Blocking PVN Y1R before stress applied in the active phase, or administering NPY to the PVN before stress applied in the inactive phase, had a resounding behavioral effect. The time at which stress occurred significantly affected the behavioral stress response. Diurnal variations in HPA and NPY/Y1R significantly affect the behavioral response, conferring more resilience at the onset of the active phase and more vulnerability at the onset of the inactive phase, implying that NPY has a significant role in conferring resilience to stress-related psychopathology.

Biological responses to trauma and the development of intrusive memories: an analog study with the trauma film paradigm

Evidence suggests that previous trauma reduces the cortisol response to subsequent stressors. We examined the relation of this response to intrusive memory, and the potential moderating roles of sympathetic reactions. Pre-existing trauma-related factors and the cardiac defense response were assessed before 58 healthy participants viewed a trauma film. Salivary cortisol and alpha-amylase (sAA) were collected pre-, peri- and post-film. Intrusive memories about the film were recorded for a week. Cortisol increased whereas sAA decreased after the film. Those with more recent traumatic experiences and greater subclinical PTSD symptoms had lower cortisol concentration post-film. Lower cortisol levels predicted greater vividness of intrusions. Positive correlations between cortisol and the frequency of intrusion were only present among individuals with more sympathetic activations. These findings suggest the contribution of insufficient cortisol secretion to over-consolidation of traumatic memory, and highlight the variation attributable to individual differences and different memory characteristics.

The role of acute cortisol and DHEAS in predicting acute and chronic PTSD symptoms

BACKGROUND

Decreased activation of the hypothalamus-pituitary-adrenal (HPA) axis in response to stress is suspected to be a vulnerability factor for posttraumatic stress disorder (PTSD). Previous studies showed inconsistent findings regarding the role of cortisol in predicting PTSD. In addition, no prospective studies have examined the role of dehydroepiandrosterone (DHEA), or its sulfate form DHEAS, and the cortisol-to-DHEA(S) ratio in predicting PTSD. In this study, we tested whether acute plasma cortisol, DHEAS and the cortisol-to-DHEAS ratio predicted PTSD symptoms at 6 weeks and 6 months post-trauma.

METHODS

Blood samples of 397 adult level-1 trauma center patients, taken at the trauma resuscitation room within hours after the injury, were analyzed for cortisol and DHEAS levels. PTSD symptoms were assessed at 6 weeks and 6 months post-trauma with the Clinician Administered PTSD Scale.

RESULTS

Multivariate linear regression analyses showed that lower cortisol predicted PTSD symptoms at both 6 weeks and 6 months, controlling for age, gender, time of blood sampling, injury, trauma history, and admission to intensive care. Higher DHEAS and a smaller cortisol-to-DHEAS ratio predicted PTSD symptoms at 6 weeks, but not after controlling for the same variables, and not at 6 months.

CONCLUSIONS

Our study provides important new evidence on the crucial role of the HPA-axis in response to trauma by showing that acute cortisol and DHEAS levels predict PTSD symptoms in survivors of recent trauma.

Awake/sleep cortisol levels and the development of posttraumatic stress disorder in injury patients with peritraumatic dissociation

Differences in the time of day that cortisol is sampled and failure to consider the impact of peritraumatic dissociation have been hypothesized as factors possibly contributing to the inconsistent findings in research examining associations between cortisol levels soon after trauma exposure and the subsequent development of posttraumatic stress disorder (PTSD). The present study examined associations between urinary cortisol levels during wake and sleep times soon after a serious injury and the subsequent development of PTSD in adult patients reporting low or high peritraumatic dissociative (PD) symptoms. Thirty-nine injury patients (20 with high and 19 with low PD symptoms) provided a 15-hour (6 PM to 9 AM) urine sample at 3-weeks post-injury and completed the Clinician Administered PTSD Scale at a 7-week follow-up. Participants collected their urine during wake and sleep times separately. Results showed that in the total sample and in the high PD group, wake, but not sleep, cortisol levels were lower in patients who developed PTSD compared to those who did not. A multiple linear regression analysis revealed a significant main effect of PD and a non-significant interaction between wake cortisol and PD in predicting PTSD symptom severity. In addition, results showed that PD was a better predictor of PTSD symptom severity than wake cortisol levels. These results were consistent with prior research indicating lower afternoon/evening cortisol levels in PTSD and strong associations between PD and PTSD, but did not support the existence of subgroups of PTSD patients (dissociators versus non-dissociators) who may differ in basal cortisol levels.

Apolipoprotein E gene polymorphism, alcohol use, and their interactions in combat-related posttraumatic stress disorder

BACKGROUND

The symptomatology of posttraumatic stress disorder (PTSD) is related not only to the intensity of the causative trauma, but also to alcohol use and genetic factors. Among the many candidate genes, the apolipoprotein E gene (APOE) is thought to be associated with stress reactivity.

METHODS

Korean veterans of the Vietnam War with (n = 128) or without (n = 128) PTSD participated in this study. The Clinician-Administered PTSD Scale and Combat Exposure Scale were administered, and the severity of alcohol use was assessed among these veterans. The APOE polymorphism and clinical variables of the subjects were compared, and associations between PTSD and potential explanatory variables were tested using logistic regression analysis.

RESULTS

Higher frequencies of APOE ε2 alleles and a greater number of individuals with the ε2 allele were found in the PTSD group. Among patients with PTSD, ε2-allele noncarriers consumed alcohol in greater amounts and more frequently than did ε2-allele carriers. Regression analysis revealed a significant interactional effect between harmful drinking and the absence of the ε2 allele associated with PTSD risk.

CONCLUSIONS

These results suggest that the APOE ε2 allele operates as a susceptibility gene for combat-related PTSD, with the relationship between alcohol use and PTSD differing according to the ε2-allele status. Future studies should determine the role of the APOE in adaptation to extreme stress, the development of PTSD, and comorbid alcohol-related disorders.

A systematic review of predictors of posttraumatic stress disorder (PTSD) for adult road traffic crash survivors

Posttraumatic stress disorder (PTSD) is one of the most common psychological consequences for adult road traffic crash (RTC) survivors and can have serious and long-lasting consequences for recovery if left untreated. Prevalence rates of PTSD following a RTC vary from 6% to 45% (based on 51 prevalence estimates across 35 studies). Explanations for this wide variance are explored. A systematic review of published studies found 49 papers (44 unique studies) investigating predictors of later PTSD in RTC survivors. Consistent predictors of PTSD include rumination about the trauma, perceived threat to life, a lack of social support, higher Acute Stress Disorder symptom severity, persistent physical problems, previous emotional problems, previous anxiety disorder and involvement in litigation/compensation. Moderate predictors of PTSD are discussed, as well as factors, which consistently do not predict PTSD in RTC survivors. The results inform future models of post-RTC traumatic stress aetiology.

Posttraumatic stress disorder: protective and risk factors in 18 survivors of a plane crash

The aim of this study is to identify protective and risk factors related to the development of posttraumatic stress disorder (PTSD) on a sample of survivors from a single plane crash. Eighteen survivors were examined 6 months following the event. The subjects all underwent psychiatric interviews, Clinician-Administered PTSD Scale structured interviews, personality and cognitive tests. Only 38.9% of them presented with all of the symptoms of PTSD; 22.2% showed no symptoms for PTSD; remaining survivors exhibited emotional/affective symptoms related to the event. In addition to the severity of the traumatic event itself, other risk factors identified were the loss of a relative, the manifestation of depressive symptoms, and the severity of physical injuries sustained. Low levels of hostility and high levels of self-efficacy represented protective factors against developing PTSD.

The effect of exogenous cortisol during sleep on the behavioral and neural correlates of emotional memory consolidation in humans

A host of animal work demonstrates that the retention benefit for emotionally aversive over neutral memories is regulated by glucocorticoid action during memory consolidation. Particularly, glucocorticoids may affect systems-level processes that promote the gradual reorganization of emotional memory traces. These effects remain largely uninvestigated in humans. Therefore, in this functional magnetic resonance imaging study we administered hydrocortisone during a polysomnographically monitored night of sleep directly after healthy volunteers studied negative and neutral pictures in a double-blind, placebo-controlled, between-subjects design. The following evening memory consolidation was probed during a recognition memory test in the MR scanner by assessing the difference in brain activity associated with memory for the consolidated items studied before sleep and new, unconsolidated items studied shortly before test (remote vs. recent memory paradigm). Hydrocortisone administration resulted in elevated cortisol levels throughout the experimental night with no group difference at recent encoding or test. Behaviorally, we showed that cortisol enhanced the difference between emotional and neutral consolidated memory, effectively prioritizing emotional memory consolidation. On a neural level, we found that cortisol reduced amygdala reactivity related to the retrieval of these same consolidated, negative items. These findings show that cortisol administration during first post-encoding sleep had a twofold effect on the first 24h of emotional memory consolidation. While cortisol prioritized recognition memory for emotional items, it reduced reactivation of the neural circuitry underlying emotional responsiveness during retrieval. These findings fit recent theories on emotional depotentiation following consolidation during sleep, although future research should establish the sleep-dependence of this effect. Moreover, our data may shed light on mechanisms underlying potential therapeutic effects of cortisol administration following psychological trauma.

Predicting PTSD: pre-existing vulnerabilities in glucocorticoid-signaling and implications for preventive interventions

Posttraumatic stress disorder (PTSD) is an anxiety disorder that may develop in response to a traumatic event. Approximately 10% of trauma-exposed individuals subsequently develop PTSD. It is hypothesized that the development of PTSD is associated with biological vulnerability factors, which are already present prior to the onset of symptoms. In this review we present an overview of currently identified vulnerability factors in the glucocorticoid (GC) signaling pathway for the development of PTSD. In addition, the implications of the identified vulnerability factors for potential preventive intervention strategies, including glucocorticoid receptor (GR) agonists and oxytocin, are discussed. Summarized, the findings of these studies indicate that individuals vulnerable for development of PTSD have dysregulations on various levels of the GC-signaling cascade: i.e. low levels of circulating levels of cortisol shortly after trauma, high GR number in peripheral blood mononuclear cells (PBMCs), high GILZ mRNA expression and low FKBP5 expression in PBMCs prior to trauma, and high sensitivity of T-cells for regulation by GCs prior to trauma. Furthermore, single nucleotide polymorphisms in the GR and FKBP5 genes have been found to be associated with increased risk for PTSD. Collectively, the identified vulnerability factors tentatively suggest that the development of PTSD may be preceded by a high sensitivity of various cells for regulation by GCs. The identification of these vulnerability factors may ultimately aid selective targeting of preventive interventions towards individuals at risk for PTSD. In addition, the identification of these vulnerability factors may eventually result in new preventive pharmacological strategies for PTSD.

Epigenetic Mechanisms Shape the Biological Response to Trauma and Risk for PTSD: A Critical Review

Posttraumatic stress disorder (PTSD) develops in approximately one-quarter of trauma-exposed individuals, leading us and others to question the mechanisms underlying this heterogeneous response to trauma. We suggest that the reasons for the heterogeneity relate to a complex interaction between genes and the environment, shaping each individual's recovery trajectory based on both historical and trauma-specific variables. Epigenetic modifications provide a unique opportunity to elucidate how preexisting risk factors may contribute to PTSD risk through changes in the methylation of DNA. Preexisting risks for PTSD, including depression, stress, and trauma, result in differential DNA methylation of endocrine genes, which may then result in a different biological responses to trauma and subsequently a greater risk for PTSD onset. Although these relationships are complex and currently inadequately described, we provide a critical review of recent studies to examine how differences in genetic and proteomic biomarkers shape an individual's vulnerability to PTSD development, thereby contributing to a heterogeneous response to trauma.