Posttraumatic stress disorder onset and inflammatory and endothelial function biomarkers in women

FLI1 in PBMCs contributes to elevated inflammation in combat-related posttraumatic stress disorder

Post-traumatic stress disorder (PTSD) is a debilitating psychiatric condition with significant public health implications that arise following exposure to traumatic events. Recent studies highlight the involvement of immune dysregulation in PTSD, characterized by elevated inflammatory markers. However, the precise mechanisms underlying this immune imbalance remain unclear. Previous research has implicated friend leukemia virus integration 1 (FLI1), an erythroblast transformation-specific (ETS) transcription factor, in inflammatory responses in sepsis and Alzheimer's disease. Elevated FLI1 levels in peripheral blood mononuclear cells (PBMCs) have been linked to lupus severity. Yet, FLI1's role in PTSD-related inflammation remains unexplored. In our study, PBMCs were collected from Veterans with and without PTSD. We found significantly increased FLI1 expression in PBMCs from PTSD-afflicted Veterans, particularly in CD4+ T cells, with no notable changes in CD8+ T cells. Stimulation with LPS led to heightened FLI1 expression and elevated levels of inflammatory cytokines IL-6 and IFNγ in PTSD PBMCs compared to controls. Knockdown of FLI1 using Gapmers in PTSD PBMCs resulted in a marked reduction in inflammatory cytokine levels, restoring them to control group levels. Additionally, co-culturing PBMCs from both control and PTSD Veterans with the human brain microglia cell line HMC3 revealed increased inflammatory mediator levels in HMC3. Remarkably, HMC3 cells co-cultured with PTSD PBMCs treated with FLI1 Gapmers exhibited significantly lower inflammatory mediator levels compared to control Gapmer-treated PTSD PBMCs. These findings suggest that suppressing FLI1 may rebalance immune activity in PBMCs and mitigate microglial activation in the brain. Such insights could provide novel therapeutic strategies for PTSD.

Post-traumatic stress in older, community-dwelling adults with hypertension during the COVID-19 pandemic: An investigation of pre-pandemic sociodemographic, health, and vascular and inflammatory biomarker predictors

COVID-19 pandemic-related traumatic stress (PRTS) symptoms are reported in various populations, but risk factors in older adults with chronic medical conditions, remain understudied. We therefore examined correlates and pre-pandemic predictors of PRTS in older adults with hypertension during COVID-19. Participants in California, aged 61-92 years (n = 95), participated in a pre-pandemic healthy aging trial and later completed a COVID-19 assessment (May to September 2020). Those experiencing ⩾1 PRTS symptom (n = 40), and those without PRTS symptoms (n = 55), were compared. The PRTS+ group had poorer mental and general health and greater impairment in instrumental activities of daily living. Pre-pandemic biomarkers of vascular inflammation did not predict increased odds of PRTS; however, greater pre-pandemic anxiety and female gender did predict PRTS during COVID-19. Our findings highlight PRTS as a threat to healthy aging in older adults with hypertension; targeted approaches are needed to mitigate this burden, particularly for females and those with pre-existing anxiety.

Alzheimer's Disease: Models and Molecular Mechanisms Informing Disease and Treatments

Alzheimer's Disease (AD) is a complex neurodegenerative disease resulting in progressive loss of memory, language and motor abilities caused by cortical and hippocampal degeneration. This review captures the landscape of understanding of AD pathology, diagnostics, and current therapies. Two major mechanisms direct AD pathology: (1) accumulation of amyloid β (Aβ) plaque and (2) tau-derived neurofibrillary tangles (NFT). The most common variants in the Aβ pathway in APP, PSEN1, and PSEN2 are largely responsible for early-onset AD (EOAD), while MAPT, APOE, TREM2 and ABCA7 have a modifying effect on late-onset AD (LOAD). More recent studies implicate chaperone proteins and Aβ degrading proteins in AD. Several tests, such as cognitive function, brain imaging, and cerebral spinal fluid (CSF) and blood tests, are used for AD diagnosis. Additionally, several biomarkers seem to have a unique AD specific combination of expression and could potentially be used in improved, less invasive diagnostics. In addition to genetic perturbations, environmental influences, such as altered gut microbiome signatures, affect AD. Effective AD treatments have been challenging to develop. Currently, there are several FDA approved drugs (cholinesterase inhibitors, Aß-targeting antibodies and an NMDA antagonist) that could mitigate AD rate of decline and symptoms of distress.

Posttraumatic Stress Disorder, Depression, and Accelerated Aging: Leukocyte Telomere Length in the Nurses' Health Study II

Background

Exposure to trauma, posttraumatic stress disorder (PTSD), and depression have been independently associated with leukocyte telomere length (LTL), a cellular marker of aging associated with mortality and age-related diseases. However, the joint contributions of trauma and its psychological sequelae on LTL have not been examined.

Methods

We conducted an analysis of LTL in a subset of women from the Nurses' Health Study II (N = 1868). Lifetime exposure to traumatic events, PTSD, and depression was assessed with validated measures. DNA was extracted from peripheral blood leukocytes and telomere repeat copy number to single gene copy number was determined by quantitative real-time polymerase chain reaction telomere assay. Linear regression models assessed the association of trauma, PTSD, and depression with LTL after adjustment for health behaviors and medical conditions.

Results

Trauma, PTSD, and depression were not independently associated with LTL in mutually adjusted models. However, individuals with severe psychological distress-characterized by comorbid PTSD and depression-had shorter LTL equivalent to being 7.62 years older (95% CI, 0.02 to 17.97) than participants who had never experienced a traumatic event and were not depressed. Further examination found only an association among individuals with the highest number of PTSD symptoms and comorbid depression equivalent to 9.71 additional years of aging (95% CI, 1.36 to 20.49). No effect was found among individuals meeting the minimum threshold for probable PTSD with comorbid depression.

Conclusions

Severe psychological distress, as indicated by the presence of comorbid PTSD and depression, may be associated with shorter LTL.

Association of systemic inflammation with posttraumatic stress disorder after a myocardial infarction

Background

Adverse mental health conditions including depression, posttraumatic stress disorder (PTSD), and anxiety are prevalent among patients who survive myocardial infarctions (MI) and are associated with adverse outcomes. The mechanisms underlying these associations, however, are not well understood. Inflammatory pathways may mediate the cardiovascular outcomes of patients with mental health disorders. We examined the bidirectional association between PTSD symptoms and inflammatory biomarkers in a young/middle-aged post MI population. We further examined how this association may differ between women and men as well as between Black and non-Black individuals.

Methods

Participants included individuals with early onset MI between the ages 25 and 60. Mental health scores for depression, PTSD, perceived stress, and anxiety as well as inflammatory biomarkers, interleukin-6 (IL-6) and high sensitivity C-reactive protein (hsCRP), were collected at baseline and at six-month follow up. We examined the bidirectional changes in mental health symptoms and inflammatory biomarkers between baseline and follow-up.

Results

Among 244 patients in the study (mean age: 50.8, 48.4% female, 64.3% Black), the geometric means for IL-6 level and hsCRP at rest were 1.7 pg/mL and 2.76 mg/L, respectively. Mental health scores at baseline did not consistently predict changes in inflammatory biomarkers at follow-up. However, baseline levels of both IL-6 and hsCRP were robustly associated with an increase in re-experiencing PTSD symptoms at 6 months: in adjusted linear mixed models, there was a 1.58-point increase in re-experiencing PTSD symptoms per unit of baseline hsCRP (p = 0.01) and 2.59-point increase per unit of baseline IL-6 (p = 0.02). Once the analysis was stratified by race, the association was only noted in Black individuals. Baseline inflammation was not associated with change in any of the other mental health symptom scores.

Conclusion

Markers of inflammation are associated with an increase in post-event PTSD symptoms in younger or middle-aged patients who experienced an MI, especially Black patients. These results suggest a mechanistic link between inflammation and the development of PTSD among individuals with cardiovascular disease.

Sex-specific immune mechanisms in PTSD symptomatology and risk: A translational overview and perspectives

Altered immune function in patients with posttraumatic stress disorder (PTSD) may play a role in the disorder pathophysiology and onset. Women are more likely to develop PTSD, suggesting potential sex-specific inflammatory mechanisms underlying the dichotomous prevalence and risk of PTSD in men and women. In this review we examine the available literature to better assess the state of knowledge in the field. In humans, increased systemic inflammation is found in both men and women with PTSD, but seems to be at a greater extend in women. Despite the existence of few clinical studies taking account of sex as a factor in the observed immune changes in PTSD, challenges in the study of sex-specific immune function in humans include: controlling for confounding variates such as the type of trauma and the ethnicity; and limited methodologies available to study central nervous system (CNS)-relevant changes. Thus, preclinical studies are a valuable tool to provide us with key insights on sex-specific peripheral and CNS immune mechanisms underlying PTSD. Available preclinical studies reported increased systemic and CNS inflammation, as well as elevated trafficking of monocytes from the periphery to the brain in both male and female rodents. To date, psychological trauma-induced inflammation is more robust in female vs male rodents. Limitations of preclinical studies include animal models hardly applicable to female rodents, and hormonal changes across estrus phases that may affect immune function. The present review: (1) highlights the key findings from both human and animal studies, (2) provides guidance to address limitations; and (3) discusses the gap of knowledge on the complex intertwined interaction between the brain, neurovascular, and systemic units.

Post-traumatic Stress Disorder: Focus on Neuroinflammation

Post-traumatic stress disorder (PTSD), gaining increasing attention, is a multifaceted psychiatric disorder that occurs following a stressful or traumatic event or series of events. Recently, several studies showed a close relationship between PTSD and neuroinflammation. Neuroinflammation, a defense response of the nervous system, is associated with the activation of neuroimmune cells such as microglia and astrocytes and with changes in inflammatory markers. In this review, we first analyzed the relationship between neuroinflammation and PTSD: the effect of stress-derived activation of the hypothalamic-pituitary-adrenal (HPA) axis on the main immune cells in the brain and the effect of stimulated immune cells in the brain on the HPA axis. We then summarize the alteration of inflammatory markers in brain regions related to PTSD. Astrocytes are neural parenchymal cells that protect neurons by regulating the ionic microenvironment around neurons. Microglia are macrophages of the brain that coordinate the immunological response. Recent studies on these two cell types provided new insight into neuroinflammation in PTSD. These contribute to promoting comprehension of neuroinflammation, which plays a pivotal role in the pathogenesis of PTSD.

Acute stress responses of autonomous nervous system, HPA axis, and inflammatory system in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) does not only have direct consequences for well-being, but it also comes with a significant risk for severe somatic health consequences. A number of previous studies have pointed to alterations in stress systems in traumatized persons, as well as the inflammatory system, which might be important links in the pathway between trauma, PTSD, and health consequences. The aim of this study was to investigate acute stress responses in PTSD patients compared with healthy controls. Twenty-seven PTSD patients and 15 controls were exposed to the Trier Social Stress Test (TSST), and we measured salivary cortisol, salivary alpha-amylase (sAA), plasma interleukin-6 (IL-6), as well as heart rate and heart rate variability (HRV) at different time points before, during and after the stress test. Results revealed similar stress responses between patients and controls, but lower baseline cortisol levels and higher IL-6 baseline levels in PTSD patients. Increases in sAA stress responses were significantly lower in patients, while sAA concentrations were higher in the PTSD group during intervention. HRV was markedly decreased in patients and showed a significantly blunted acute stress response with a slower recovery after TSST. These results confirm previous findings of marked stress system dysregulations in PTSD and add to the literature on acute stress reactivity in PTSD which appears to show stress system-specific changes. Overall, these results have implications for our understanding of potential risk and resilience factors in the response to trauma.

C-Reactive Protein (CRP): A Potent Inflammation Biomarker in Psychiatric Disorders

An increasing number of studies have investigated the role of inflammation in psychiatric disorders, by demonstrating how an altered/dysfunctional immunological and inflammatory system may underpin a psychiatric condition. Particularly, several studies specifically investigated the role of a neuroinflammatory biomarker, named C-reactive protein (CRP), in psychiatric disorders. Overall, even though scientific literature so far published still does not appear definitive, CRP is more likely reported to be elevated in several psychiatric disorders, including schizophrenia, mood disorders, anxiety disorders and post-traumatic stress disorder. Moreover, a low-grade inflammation (CRP >3 mg/L) has been more likely observed in a subgroup of patients affected with a more severe psychopathological symptomatology, more treatment resistance and worst clinical mental illness course, strengthening the hypothesis of the need for a different clinical and prognostic characterization based on this concomitant neuroinflammatory predisposition. However, even though further research studies are needed to confirm this preliminary evidence, CRP may represent a potential clinical routine biomarker which could be integrated in the clinical routine practice to better characterize clinical picture and course as well as address clinicians towards a personalized treatment.

Potential peripheral biomarkers associated with the emergence and presence of posttraumatic stress disorder symptomatology: A systematic review

BACKGROUND

Evidence suggests posttraumatic stress disorder (PTSD) involves an interplay between psychological manifestations and biological systems. Biological markers of PTSD could assist in identifying individuals with underlying dysregulation and increased risk; however, accurate and reliable biomarkers are yet to be identified.

METHODS

A systematic review following the PRISMA guidelines was conducted. Databases included EMBASE, MEDLINE, and Cochrane Central. Studies from a comprehensive 2015 review (Schmidt et al., 2015) and English language papers published subsequently (between 2014 and May 2022) were included. Forty-eight studies were eligible.

RESULTS

Alterations in neuroendocrine and immune markers were most commonly associated with PTSD symptoms. Evidence indicates PTSD symptoms are associated with hypothalamic-pituitary-adrenal axis dysfunction as represented by low basal cortisol, a dysregulated immune system, characterized by an elevated pro-inflammatory state, and metabolic dysfunction. However, a considerable number of studies neglected to measure sex or prior trauma, which have the potential to affect the biological outcomes of posttraumatic stress symptoms. Mixed findings are indicative of the complexity and heterogeneity of PTSD and suggest the relationship between allostatic load, biological markers, and PTSD remain largely undefined.

CONCLUSIONS

In addition to prospective research design and long-term follow up, it is imperative future research includes covariates sex, prior trauma, and adverse childhood experiences. Future research should include exploration of biological correlates specific to PTSD symptom domains to determine whether underlying processes differ with symptom expression, in addition to subclinical presentation of posttraumatic stress symptoms, which would allow for greater understanding of biomarkers associated with disorder risk and assist in untangling directionality.

PTSD, Immune System, and Inflammation

Posttraumatic stress disorder (PTSD) is a severe trauma and stress-related disorder associated with different somatic comorbidities, especially cardiovascular and metabolic disorders, and with chronic low-grade inflammation. Altered balance of the hypothalamic-pituitary-adrenal (HPA) axis, cytokines and chemokines, C-reactive protein, oxidative stress markers, kynurenine pathways, and gut microbiota might be involved in the alterations of certain brain regions regulating fear conditioning and memory processes, that are all altered in PTSD. In addition to the HPA axis, the gut microbiota maintains the balance and interaction of the immune, CNS, and endocrine pathways forming the gut-brain axis. Disbalance in the HPA axis, gut-brain axis, oxidative stress pathways and kynurenine pathways, altered immune signaling and disrupted homeostasis, as well as the association of the PTSD with the inflammation and disrupted cognition support the search for novel strategies for treatment of PTSD. Besides potential anti-inflammatory treatment, dietary interventions or the use of beneficial bacteria, such as probiotics, can potentially improve the composition and the function of the bacterial community in the gut. Therefore, bacterial supplements and controlled dietary changes, with exercise, might have beneficial effects on the psychological and cognitive functions in patients with PTSD. These new treatments should be aimed to attenuate inflammatory processes and consequently to reduce PTSD symptoms but also to improve cognition and reduce cardio-metabolic disorders associated so frequently with PTSD.

Vagal control moderates the association between endothelial function and PTSD symptoms in women with T2DM

Background

Individuals with posttraumatic stress disorder (PTSD) are more likely to present with metabolic diseases such as type-2 diabetes mellitus (T2DM), and cardiovascular dysfunction has been implicated in this link. These diseases disproportionately affect women and individuals exposed to chronic environmental stressors (e.g., community violence, poverty). We examined associations among PTSD, cardiovascular indices, and metabolic function in highly trauma-exposed Black women with T2DM.

Methods

Participants (N = 80) were recruited for a follow-up study of stress and T2DM as part of the Grady Trauma Project. PTSD symptoms were assessed with the Clinician Administered PTSD Scale (CAPS-IV). Cardiovascular indices included heart rate (HR), blood pressure (BP), respiratory sinus arrhythmia (RSA), and endothelial function (assessed via flow-mediated dilation; FMD). An oral glucose tolerance test was used as an indicator of metabolic function.

Results

Of the cardiovascular indices, only FMD was significantly associated with PTSD symptoms (CAPS Avoidance symptoms; β = -0.37, p = .042), and glucose tolerance (β = -0.44, p = .019), controlling for age and body mass index. The association between FMD and PTSD Avoidance was moderated by RSA such that the effect of FMD was only significant at low levels of RSA (simple slopes β = -0.87, p = .004).

Conclusions

Our results indicate that endothelial function is significantly related to PTSD and glucose tolerance, over and above other cardiovascular measures (HR, BP, RSA). Further, our results suggest that low RSA may be a risk factor for the link between poor endothelial function and PTSD in women with T2DM.

Stress- and drug-induced neuroimmune signaling as a therapeutic target for comorbid anxiety and substance use disorders

Stress and substance use disorders remain two of the most highly prevalent psychiatric conditions and are often comorbid. While individually these conditions have a debilitating impact on the patient and a high cost to society, the symptomology and treatment outcomes are further exacerbated when they occur together. As such, there are few effective treatment options for these patients, and recent investigation has sought to determine the neural processes underlying the co-occurrence of these disorders to identify novel treatment targets. One such mechanism that has been linked to stress- and addiction-related conditions is neuroimmune signaling. Increases in inflammatory factors across the brain have been heavily implicated in the etiology of these disorders, and this review seeks to determine the nature of this relationship. According to the "dual-hit" hypothesis, also referred to as neuroimmune priming, prior exposure to either stress or drugs of abuse can sensitize the neuroimmune system to be hyperresponsive when exposed to these insults in the future. This review completes an examination of the literature surrounding stress-induced increases in inflammation across clinical and preclinical studies along with a summarization of the evidence regarding drug-induced alterations in inflammatory factors. These changes in neuroimmune profiles are also discussed within the context of their impact on the neural circuitry responsible for stress responsiveness and addictive behaviors. Further, this review explores the connection between neuroimmune signaling and susceptibility to these conditions and highlights the anti-inflammatory pharmacotherapies that may be used for the treatment of stress and substance use disorders.

Trauma, psychological distress and markers of systemic inflammation among US women: A longitudinal study

BACKGROUND

Prior evidence links posttraumatic stress disorder (PTSD) and depression, separately, with chronic inflammation. However, whether effects are similar across each independently or potentiated when both are present is understudied. We evaluated combined measures of PTSD and depression in relation to inflammatory biomarker concentrations.

METHODS

Data are from women (n's ranging 628-2797) in the Nurses' Health Study II. Trauma exposure, PTSD, and depression symptoms were ascertained using validated questionnaires. We examined (a) a continuous combined psychological distress score summing symptoms for PTSD and depression, and (b) a categorical cross-classified measure of trauma/PTSD symptoms/depressed mood status (reference group: no trauma or depressed mood). Three inflammatory biomarkers (C-reactive protein [CRP], interleukin-6 [IL-6], tumor necrosis factor alpha receptor 2 [TNFR2]) were assayed from at least one of two blood samples collected 10-16 years apart. We examined associations of our exposures with levels of each biomarker concentration (log-transformed and batch-corrected) as available across the two time points (cross-sectional analyses; CRP, IL-6 and TNFR2) and with rate of change in biomarkers across time (longitudinal analyses; CRP and IL-6) using separate linear mixed effects models.

RESULTS

In sociodemographic-adjusted models accounting for trauma exposure, a one standard deviation increase in the continuous combined psychological distress score was associated with 10.2% (95% confidence interval (CI): 5.2-15.4%) higher CRP and 1.5% (95% CI: 0.5-2.5%) higher TNFR2 concentrations cross-sectionally. For the categorical exposure, women with trauma/PTSD symptoms/ depressed mood versus those with no trauma or depressed mood had 29.5% (95% CI: 13.3-47.9%) higher CRP and 13.1% (95% CI: 5.1-21.7%) higher IL-6 cross-sectionally. In longitudinal analysis, trauma/PTSD symptoms/depressed mood was associated with increasing CRP levels over time.

CONCLUSIONS

High psychological distress levels with trauma exposure is associated with elevated inflammation and is a potential biologic pathway by which distress can impact development of inflammatory-related chronic diseases, such as cardiovascular disease. Considering multiple forms of distress in relation to these pathways may provide greater insight into who is at risk for biologic dysregulation and later susceptibility to chronic diseases.

The role of the immune system in posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) develops in a subset of individuals upon exposure to traumatic stress. In addition to well-defined psychological and behavioral symptoms, some individuals with PTSD also exhibit elevated concentrations of inflammatory markers, including C-reactive protein, interleukin-6, and tumor necrosis factor-α. Moreover, PTSD is often co-morbid with immune-related conditions, such as cardiometabolic and autoimmune disorders. Numerous factors, including lifetime trauma burden, biological sex, genetic background, metabolic conditions, and gut microbiota, may contribute to inflammation in PTSD. Importantly, inflammation can influence neural circuits and neurotransmitter signaling in regions of the brain relevant to fear, anxiety, and emotion regulation. Given the link between PTSD and the immune system, current studies are underway to evaluate the efficacy of anti-inflammatory treatments in those with PTSD. Understanding the complex interactions between PTSD and the immune system is essential for future discovery of diagnostic and therapeutic tools.

Inflammatory and oxidative stress markers in post-traumatic stress disorder: a systematic review and meta-analysis

Post-traumatic stress disorder (PTSD) has been associated with persistent, low-degree inflammation, which could explain the increased prevalence of autoimmune conditions and accelerated aging among patients. The aim of the present study is to assess which inflammatory and oxidative stress markers are associated with PTSD. We carried out a meta-analytic and meta-regression analysis based on a systematic review of studies comparing inflammatory and oxidative stress markers between patients with PTSD and controls. We undertook meta-analyses whenever values of inflammatory and oxidative stress markers were available in two or more studies. Overall, 28,008 abstracts were identified, and 54 studies were included, with a total of 8394 participants. The Newcastle-Ottawa Quality Assessment Scale was used to evaluate the quality of the studies. Concentrations of C-reactive protein (SMD = 0.64; 95% CI: 0.21 to 1.06; p = 0.0031; k = 12), interleukin 6 (SMD = 0.94; 95% CI: 0.36 to 1.52; p = 0.0014; k = 32), and tumor necrosis factor-α (SMD = 0.89; 95% CI: 0.23 to 1.55; p = 0.0080; k = 24) were significantly increased in patients with PTSD in comparison with healthy controls. Interleukin 1β levels almost reached the threshold for significance (SMD = 1.20; 95% CI: -0.04 to 2.44; p = 0.0569; k = 15). No oxidative stress marker was associated with PTSD. These findings may explain why PTSD is associated with accelerated aging and illnesses in which immune activation has a key role, such as cardiovascular diseases and diabetes. In addition, they pointed to the potential role of inflammatory markers as therapeutic targets.

Understanding the Concept of Pre-Clinical Autoimmunity: Prediction and Prevention of Systemic Lupus Erythematosus: Identifying Risk Factors and Developing Strategies Against Disease Development

There is growing evidence that preceding the diagnosis or classification of systemic lupus erythematosus (SLE), patients undergo a preclinical phase of disease where markers of inflammation and autoimmunity are already present. Not surprisingly then, even though SLE management has improved over the years, many patients will already have irreversible disease-related organ damage by time they have been diagnosed with SLE. By gaining a greater understanding of the pathogenesis of preclinical SLE, we can potentially identify patients earlier in the disease course who are at-risk of transitioning to full-blown SLE and implement preventative strategies. In this review, we discuss the current state of knowledge of SLE preclinical pathogenesis and propose a screening and preventative strategy that involves the use of promising biomarkers of early disease, modification of lifestyle and environmental risk factors, and initiation of preventative therapies, as examined in other autoimmune diseases such as rheumatoid arthritis and type 1 diabetes.

Association of Posttraumatic Stress Disorder With Accelerated Cognitive Decline in Middle-aged Women

IMPORTANCE

Posttraumatic stress disorder (PTSD) has been hypothesized to lead to impaired cognitive function. However, no large-scale studies have assessed whether PTSD is prospectively associated with cognitive decline in middle-aged adults.

OBJECTIVE

To assess the association between PTSD and decline in cognitive function over time.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included participants from the Nurses' Health Study II, an ongoing longitudinal cohort study involving community-dwelling middle-aged female nurses residing in the US who had at least a 2-year nursing degree at the time of enrollment in 1989. The present study included 12 270 trauma-exposed women who were enrolled in the PTSD substudy of the Nurses' Health Study II and completed 1 to 5 cognitive assessments. Data were collected from March 1, 2008, to July 30, 2019.

EXPOSURES

Lifetime PTSD symptoms, assessed using a validated questionnaire between March 1, 2008, and February 28, 2010.

MAIN OUTCOMES AND MEASURES

The main outcome was evaluated using the Cogstate Brief Battery, a self-administered online cognitive battery. Cognitive function was measured by a psychomotor speed and attention composite score and a learning and working memory composite score. Women completed the Cogstate Brief Battery every 6 or 12 months (up to 24 months) from October 3, 2014, to July 30, 2019. Linear mixed-effects models were used to evaluate the association of PTSD symptoms with the rate of change in cognition over follow-up, considering a broad range of relevant covariates, including the presence of depression symptoms and history of clinician-diagnosed depression. The rate of cognitive change was adjusted for potential practice effects (ie, potential changes in test results that occur when a test is taken more than once) by including indicators for the number of previous tests taken.

RESULTS

Among 12 270 women, the mean (SD) age at the baseline cognitive assessment was 61.1 (4.6) years; 125 women (1.0%) were Asian, 75 (0.6%) were Black, 156 (1.3%) were Hispanic, 11 767 (95.9%) were non-Hispanic White, and 147 (1.2%) were of other race and/or ethnicity. A higher number of PTSD symptoms was associated with worse cognitive trajectories. Compared with women with no PTSD symptoms, women with the highest symptom level (6-7 symptoms) had a significantly worse rate of change in both learning and working memory (β = -0.08 SD/y; 95% CI, -0.11 to -0.04 SD/y; P < .001) and psychomotor speed and attention (β = -0.05 SD/y; 95% CI, -0.09 to -0.01 SD/y; P = .02), adjusted for demographic characteristics. Associations were unchanged when additionally adjusted for behavioral factors (eg, 6-7 symptoms in the analysis of learning and working memory: β = -0.08 SD/y; 95% CI, -0.11 to -0.04 SD/y; P < .001) and health conditions (eg, 6-7 symptoms in the analysis of learning and working memory: β = -0.08 SD/y; 95% CI, -0.11 to -0.04 SD/y; P < .001) and were partially attenuated but still evident when further adjusted for practice effects (eg, 6-7 symptoms in the analysis of learning and working memory: β = -0.07 SD/y; 95% CI, -0.10 to -0.03 SD/y; P < .001) and comorbid depression (eg, 6-7 symptoms in the analysis of learning and working memory: β = -0.07 SD/y; 95% CI, -0.11 to -0.03 SD/y; P < .001).

CONCLUSIONS AND RELEVANCE

In this large-scale prospective cohort study, PTSD was associated with accelerated cognitive decline in middle-aged women, suggesting that earlier cognitive screening among women with PTSD may be warranted. Given that cognitive decline is strongly associated with subsequent Alzheimer disease and related dementias, better understanding of this association may be important to promote healthy aging.

C-Reactive Protein: Marker of risk for post-traumatic stress disorder and its potential for a mechanistic role in trauma response and recovery

Increasing evidence indicates that inflammation plays a role in PTSD and stress disorder pathophysiology. PTSD is consistently associated with higher circulating inflammatory protein levels. Rodent models demonstrate that inflammation promotes enduring avoidance and arousal behaviors after severe stressors (e.g., predator exposure and social defeat), suggesting that inflammation may play a mechanistic role in trauma disorders. C-reactive protein (CRP) is an innate acute phase reactant produced by the liver after acute infection and chronic disease. A growing number of investigations report associations with PTSD diagnosis and elevated peripheral CRP, CRP gene mutations, and CRP gene expression changes in immune signaling pathways. CRP is reasonably established as a potential marker of PTSD and trauma exposure, but if and how it may play a mechanistic role is unclear. In this review, we discuss the current understanding of immune mechanisms in PTSD with a particular focus on the innate immune signaling factor, CRP. We found that although there is consistent evidence of an association of CRP with PTSD symptoms and risk, there is a paucity of data on how CRP might contribute to CNS inflammation in PTSD, and consequently, PTSD symptoms. We discuss potential mechanisms through which CRP could modulate enduring peripheral and CNS stress responses, along with future areas of investigation probing the role of CRP and other innate immune signaling factors in modulating trauma responses. Overall, we found that CRP likely contributes to central inflammation, but how it does so is an area for further study.

A Systematic Review of Research on Trauma and Women's Health in the Nurses' Health Study II

OBJECTIVE

To synthesize research on interpersonal trauma and women's health from the Nurses' Health Study II (NHS II) and to analyze conceptualization of interpersonal trauma across studies.

DATA SOURCES

A literature review was conducted in PubMed using a systematic search strategy.

STUDY SELECTION

Articles were included in the review if they used data from the NHS II and involved investigations of interpersonal trauma. Theoretical articles, methodologic articles, and other literature reviews involving the NHS II were excluded. Initially, the search returned 61 articles. After exclusions, 45 articles met the criteria for inclusion in the review and data extraction.

DATA EXTRACTION

Information was extracted and consolidated in an evidence table. Data included study time frame, sample, definition of trauma, outcomes studied, and journal of publication.

DATA SYNTHESIS

Trauma was not operationalized consistently across studies, even though the NHS II assessed trauma experiences in childhood, adolescence, and adulthood. Most investigations focused on childhood abuse, with investigations of childhood sexual abuse overrepresented in comparison to other abuse experiences. Authors conducting studies of trauma at any time in the life course consistently found a negative association with physical and mental health outcomes, which were increased by the presence of posttraumatic stress symptoms. Results from a small number of studies suggested a negative intergenerational impact of trauma on the children of women in the NHS II.

CONCLUSION

Interpersonal trauma across the life course was strongly associated with many leading causes of morbidity and mortality among female nurses. Trauma conceptualization and operationalization varied across studies, and future investigations should leverage the full range of trauma measures available in the NHS II data set.

The association of posttraumatic stress disorder, depression, and head injury with mid-life cognitive function in civilian women

BACKGROUND

Despite evidence linking posttraumatic stress disorder (PTSD), depression, and head injury, separately, with worse cognitive performance, investigations of their combined effects on cognition are limited in civilian women.

METHODS

The Cogstate Brief Battery assessment was administered in 10,681 women from the Nurses' Health Study II cohort, mean age 64.9 years (SD = 4.6). Psychological trauma, PTSD, depression, and head injury were assessed using online questionnaires. In this cross-sectional analysis, we used linear regression models to estimate mean differences in cognition by PTSD/depression status and stratified by history of head injury.

RESULTS

History of head injury was prevalent (36%), and significantly more prevalent among women with PTSD and depression (57% of women with PTSD and depression, 21% of women with no psychological trauma or depression). Compared to having no psychological trauma or depression, having combined PTSD and depression was associated with worse performance on psychomotor speed/attention ( β  = -.15, p = .001) and learning/working memory ( β  = -.15, p < .001). The joint association of PTSD and depression on worse cognitive function was strongest among women with past head injury, particularly among those with multiple head injuries.

CONCLUSIONS

Head injury, like PTSD and depression, was highly prevalent in this sample of civilian women. In combination, these factors were associated with poorer performance on cognitive tasks, a possible marker of future cognitive health. Head injury should be further explored in future studies of PTSD, depression and cognition in women.

Prospective association between pro-inflammatory state on admission and posttraumatic stress following acute coronary syndrome

OBJECTIVE

The traumatic experience of acute coronary syndrome (ACS) may induce symptoms of posttraumatic stress disorder (PTSD). We examined whether the ACS-triggered acute inflammatory response predicts the development of PTSD symptoms.

METHOD

Study participants were 70 patients (all Caucasian, 80% male, mean age 59 years) with myocardial infarction (MI) during the acute treatment phase. Interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, IL-4, IL-10, and transforming growth factor (TGF)-1β were determined in plasma collected within 48 h of hospital admission. Participants self-assessed the severity of ACS-induced PTSD symptoms with the 17-item Posttraumatic Diagnostic Scale at 12 months.

RESULTS

There was a significant positive association of the pro-inflammatory index (added standardized z-scores of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α) with total PTSD symptom severity (ΔR² = 0.050, p = .029) and re-experiencing symptoms (ΔR² = 0.088, p = .008), but not avoidance/numbing and hyperarousal symptoms. Analyses were adjusted for the anti-inflammatory index (added standardized z-scores of IL-4, IL-10, and TGF-β1), trauma-focused counseling, sex, age, time since pain onset, troponin, body mass index, and distress during MI. Results were robust when the anti-inflammatory index was removed from the model. Additional analyses showed significant associations of both the net-inflammatory index (i.e., pro-inflammatory index minus anti-inflammatory index) and IL-1β with total PTSD symptom severity, re-experiencing, and hyperarousal symptoms (ΔR² between 0.042 and 0.090) and of IL-1β with avoidance/numbing symptoms (ΔR² = 0.050).

CONCLUSIONS

The findings suggest an association between the pro-inflammatory state launched during ACS and the development of PTSD symptoms. Increased IL-1β may play a particular role in the pathophysiology of ACS-induced PTSD symptoms.

Immunomodulatory Role of CB2 Receptors in Emotional and Cognitive Disorders

Emotional behavior, memory, and learning have been associated with alterations in the immune system in neuropsychiatric and neurodegenerative diseases. In recent years, several studies pointed out the involvement of the cannabinoid receptor 2 (CB2r) in the immune system and the regulation of inflammation. This receptor is widely distributed in different tissues and organs with higher expression in spleen and immune system cells. However, CB2r has also been detected in several brain areas and different brain cell types, such as neurons and glia. These findings suggest that CB2r may closely relate the immune system and the brain circuits regulating inflammation, mood, and cognitive functions. Therefore, we review the studies that may help elucidate the molecular bases of CB2r in regulating inflammation in different brain cells and its role in the pathophysiology of psychiatric and neurodegenerative disorders.

Gene expression correlates of advanced epigenetic age and psychopathology in postmortem cortical tissue

Psychiatric stress has been associated with accelerated epigenetic aging (i.e., when estimates of cellular age based on DNA methylation exceed chronological age) in both blood and brain tissue. Little is known about the downstream biological effects of accelerated epigenetic age on gene expression. In this study we examined associations between DNA methylation-derived estimates of cellular age that range from decelerated to accelerated relative to chronological age (“DNAm age residuals”) and transcriptome-wide gene expression. This was examined using tissue from three post-mortem cortical regions (ventromedial and dorsolateral prefrontal cortex and motor cortex, n = 97) from the VA National PTSD Brain Bank. In addition, we examined how posttraumatic stress disorder (PTSD) and alcohol-use disorders (AUD) moderated the association between DNAm age residuals and gene expression. Transcriptome-wide results across brain regions, psychiatric diagnoses, and cohorts (full sample and male and female subsets) revealed experiment-wide differential expression of 11 genes in association with PTSD or AUD in interaction with DNAm age residuals. This included the inflammation-related genes IL1B, RCOR2, and GCNT1. Candidate gene class analyses and gene network enrichment analyses further supported differential expression of inflammation/immune gene networks as well as glucocorticoid, circadian, and oxidative stress-related genes. Gene co-expression network modules suggested enrichment of myelination related processes and oligodendrocyte enrichment in association with DNAm age residuals in the presence of psychopathology. Collectively, results suggest that psychiatric stress accentuates the association between advanced epigenetic age and expression of inflammation genes in the brain. This highlights the role of inflammatory processes in the pathophysiology of accelerated cellular aging and suggests that inflammatory pathways may link accelerated cellular aging to premature disease onset and neurodegeneration, particularly in stressed populations. This suggests that anti-inflammatory interventions may be an important direction to pursue in evaluating ways to prevent or delay cellular aging and increase resilience to diseases of aging.

Translational relevance of fear conditioning in rodent models of mild traumatic brain injury

Mild traumatic brain injury (mTBI) increases the risk of posttraumatic stress disorder (PTSD) in military populations. Utilizing translationally relevant animal models is imperative for establishing a platform to delineate neurobehavioral deficits common to clinical PTSD that emerge in the months to years following mTBI. Such platforms are required to facilitate preclinical development of novel therapeutics. First, this mini review provides an overview of the incidence of PTSD following mTBI in military service members. Secondly, the translational relevance of fear conditioning paradigms used in conjunction with mTBI in preclinical studies is evaluated. Next, this review addresses an important gap in the current preclinical literature; while incubation of fear has been studied in other areas of research, there are relatively few studies pertaining to the enhancement of cued and contextual fear memory over time following mTBI. Incubation of fear paradigms in conjunction with mTBI are proposed as a novel behavioral approach to advance this critical area of research. Lastly, this review discusses potential neurobiological substrates implicated in altered fear memory post mTBI.

Dissecting the genetic association of C-reactive protein with PTSD, traumatic events, and social support

Inflammatory markers like C-reactive protein (CRP) have been associated with post-traumatic stress disorder (PTSD) and traumatic experiences, but the underlying mechanisms are unclear. We investigated the relationship among serum CRP, PTSD, and traits related to traumatic events and social support using genetic association data from the Psychiatric Genomics Consortium (23,185 PTSD cases and 151,309 controls), the UK Biobank (UKB; up to 117,900 individuals), and the CHARGE study (Cohorts for Heart and Aging Research in Genomic Epidemiology, 148,164 individual). Linkage disequilibrium score regression, polygenic risk scoring, and two-sample Mendelian randomization (MR) analyses were used to investigate genetic overlap and causal relationships. Genetic correlations of CRP were observed with PTSD (rg = 0.16, p = 0.026) and traits related to traumatic events, and the presence of social support (-0.28 < rg < 0.20; p < 0.008). We observed a bidirectional association between CRP and PTSD (CRP → PTSD: β = 0.065, p = 0.015; PTSD → CRP: β = 0.008, p = 0.009). CRP also showed a negative association with the "felt loved as a child" trait (UKB, β = -0.017, p = 0.008). Owing to the known association of socioeconomic status (SES) on PTSD, a multivariable MR was performed to investigate SES as potential mediator. We found that household income (univariate MR: β = -0.22, p = 1.57 × 10-7; multivariate MR: β = -0.17, p = 0.005) and deprivation index (univariate MR: β = 0.38, p = 1.63 × 10-9; multivariate MR: β = 0.27, p = 0.016) were driving the causal estimates of "felt loved as a child" and CRP on PTSD. The present findings highlight a bidirectional genetic association between PTSD and CRP, also suggesting a potential role of SES in the interplay between childhood support and inflammatory processes with respect to PTSD risk.

Inflammation-driven brain and gut barrier dysfunction in stress and mood disorders

Regulation of emotions is generally associated exclusively with the brain. However, there is evidence that peripheral systems are also involved in mood, stress vulnerability vs. resilience, and emotion‐related memory encoding. Prevalence of stress and mood disorders such as major depression, bipolar disorder, and post‐traumatic stress disorder is increasing in our modern societies. Unfortunately, 30%–50% of individuals respond poorly to currently available treatments highlighting the need to further investigate emotion‐related biology to gain mechanistic insights that could lead to innovative therapies. Here, we provide an overview of inflammation‐related mechanisms involved in mood regulation and stress responses discovered using animal models. If clinical studies are available, we discuss translational value of these findings including limitations. Neuroimmune mechanisms of depression and maladaptive stress responses have been receiving increasing attention, and thus, the first part is centered on inflammation and dysregulation of brain and circulating cytokines in stress and mood disorders. Next, recent studies supporting a role for inflammation‐driven leakiness of the blood–brain and gut barriers in emotion regulation and mood are highlighted. Stress‐induced exacerbated inflammation fragilizes these barriers which become hyperpermeable through loss of integrity and altered biology. At the gut level, this could be associated with dysbiosis, an imbalance in microbial communities, and alteration of the gut–brain axis which is central to production of mood‐related neurotransmitter serotonin. Novel therapeutic approaches such as anti‐inflammatory drugs, the fast‐acting antidepressant ketamine, and probiotics could directly act on the mechanisms described here improving mood disorder‐associated symptomatology. Discovery of biomarkers has been a challenging quest in psychiatry, and we end by listing promising targets worth further investigation.

Post-traumatic stress impact on health outcomes in Gulf War Illness

BACKGROUND

Gulf War Illness (GWI) is a chronic, multi-symptomatic disorder affecting an estimated 25-32% of the returning military veterans of the 1990-1991 Persian Gulf War. GWI presents with a wide range of symptoms including fatigue, muscle pain, cognitive problems, insomnia, rashes and gastrointestinal issues and continues to be a poorly understood illness. This heterogeneity of GWI symptom presentation complicates diagnosis as well as the identification of effective treatments. Defining subgroups of the illness may help alleviate these complications. Our aim is to determine if GWI can be divided into distinct subgroups based on PTSD symptom presentation.

METHODS

Veterans diagnosed with GWI (n = 47) and healthy sedentary veteran controls (n = 52) were recruited through the Miami Affairs (VA) Medical Health Center. Symptoms were assessed via the RAND short form health survey (36), the multidimensional fatigue inventory, and the Davidson trauma scale. Hierarchal regression modeling was performed on measures of health and fatigue with PTSD symptoms as a covariate. This was followed by univariate analyses conducted with two separate GWI groups based on a cut-point of 70 for their total Davidson Trauma Scale value and performing heteroscedastic t-tests across all measures.

RESULTS

Overall analyses returned two symptom-based subgroups differing significantly across all health and trauma symptoms. These subgroups supported PTSD symptomatology as a means to subgroup veterans. Hierarchical models showed that GWI and levels of PTSD symptoms both impact measures of physical, social, and emotional consequences of poor health (ΔR2 = 0.055-0.316). However, GWI appeared to contribute more to fatigue measures. Cut-point analysis retained worse health outcomes across all measures for GWI with PTSD symptoms compared to those without PTSD symptoms, and healthy controls. Significant differences were observed in mental and emotional measures.

CONCLUSIONS

Therefore, this research supports the idea that comorbid GWI and PTSD symptoms lead to worse health outcomes, while demonstrating how GWI and PTSD symptoms may uniquely contribute to clinical presentation.

Psychological Health, Well-Being, and the Mind-Heart-Body Connection: A Scientific Statement From the American Heart Association

As clinicians delivering health care, we are very good at treating disease but often not as good at treating the person. The focus of our attention has been on the specific physical condition rather than the patient as a whole. Less attention has been given to psychological health and how that can contribute to physical health and disease. However, there is now an increasing appreciation of how psychological health can contribute not only in a negative way to cardiovascular disease (CVD) but also in a positive way to better cardiovascular health and reduced cardiovascular risk. This American Heart Association scientific statement was commissioned to evaluate, synthesize, and summarize for the health care community knowledge to date on the relationship between psychological health and cardiovascular health and disease and to suggest simple steps to screen for, and ultimately improve, the psychological health of patients with and at risk for CVD. Based on current study data, the following statements can be made: There are good data showing clear associations between psychological health and CVD and risk; there is increasing evidence that psychological health may be causally linked to biological processes and behaviors that contribute to and cause CVD; the preponderance of data suggest that interventions to improve psychological health can have a beneficial impact on cardiovascular health; simple screening measures can be used by health care providers for patients with or at risk for CVD to assess psychological health status; and consideration of psychological health is advisable in the evaluation and management of patients with or at risk for CVD.

Sex differences in the association between PTSD symptoms with cardiac autonomic function and subclinical atherosclerotic risk

BACKGROUND

Post-traumatic stress disorder (PTSD) is a public health concern that may elevate the risk for cardiovascular disease (CVD). There are established sex differences in both PTSD risk and CVD risk.

PURPOSE

To examine sex-specific associations between subclinical PTSD symptom severity and subclinical CVD risk in young men and women.

METHODS

A total of 61 young adults (women: n = 29, mean age: 26 ± 7 years) completed the post-traumatic stress disorder civilian checklist (PCL) and the Center for Epidemiologic Studies Depression Scale (CES-D). Aortic stiffness was measured as carotid-femoral pulse wave velocity (cfPWV). Peripheral vasomotor function was measured as flow-mediated slowing (FMS) of carotid-radial PWV following 5-min forearm occlusion. Heart rate variability was used to assess sympathovagal balance as LF/HF ratio.

RESULTS

PCL score was positively correlated with CES-D score (r = 0.79, p < .001), cfPWV (r = 0.33, p = .03) and LF/HF ratio (r = 0.42, p = .009) in men. PCL score was positively correlated to CES-D score (r = 0.80, p < .001) in women, but was inversely correlated to cfPWV (r = -0.38, p = .02) and LF/HF ratio (r = -0.34, p = .04). PCL score was also inversely associated with FMS in women (r = -0.49, p = .01).

CONCLUSION

There are sex differences in the association of PTSD symptoms and subclinical atherosclerosis. In men, increased PTSD symptoms may increase CVD risk by increasing sympathovagal balance and aortic stiffness. In women, increased PTSD symptoms may increase CVD risk via reducing vasomotor function.

Posttraumatic Stress Disorder and Inflammation: Untangling Issues of Bidirectionality

Posttraumatic stress disorder (PTSD) has increasingly been linked to heightened systemic inflammation. It matters whether this association is causal (and either bidirectional or unidirectional) or correlational. Investigators have hypothesized that chronic systemic low-grade inflammation may contribute to greater risk of developing PTSD after experiencing trauma and/or serve as a mechanism linking PTSD to adverse physical health outcomes. However, if the PTSD-inflammation relation is correlational, it may not warrant further research aimed at understanding inflammation as a PTSD risk factor or as a pathway linking PTSD with poor health. In this review, we first assess the longitudinal evidence related to PTSD and inflammation to understand more clearly the directionality and causal nature of this relation. Overall, few longitudinal studies rigorously assess the direction of the PTSD-inflammation relation. Some of the evidence indicates that elevated inflammation assessed pretrauma or in the acute aftermath of trauma increases risk for developing PTSD. Fewer studies evaluate the influence of PTSD on subsequent inflammation levels, and findings are mixed. Sample characteristics and study designs, and also the type of inflammation-related measure, vary widely across studies. Based on current evidence, we then recommend several statistical and study design approaches that may help untangle issues of bidirectionality and aid in determining the direction of causality between PTSD and inflammation. Last, we conclude with future research directions and consider potential implications for interventions or treatment approaches based on this growing body of literature.

Nervous and Endocrine System Dysfunction in Posttraumatic Stress Disorder: An Overview and Consideration of Sex as a Biological Variable

Decades of research into the biological mechanisms of posttraumatic stress disorder (PTSD) suggests that chronic activation of the stress response leads to long-lasting changes in the structure and function of the nervous and endocrine systems. While the prevalence of PTSD is twice as high in females as males, little is known about how sex differences in neuroendocrine systems may contribute to PTSD. In response to the paucity of research on sex-related mechanisms, the National Institutes of Health created a policy that asks researchers to consider sex as a biological variable. This review provides an overview of the current understanding of nervous and endocrine dysfunction in PTSD (e.g., neural circuitry, autonomic arousal, hormonal response), highlighting areas where the influence of sex has been characterized and where further research is needed. We also provide recommendations for using the sex-as-a-biological-variable policy to address specific gaps in PTSD neuroscience research.

Family Member Incarceration, Psychological Stress, and Subclinical Cardiovascular Disease in Mexican Women (2012-2016)

Objectives. To examine the association between family member incarceration, psychological stress, and subclinical cardiovascular disease (CVD).Methods. Between 2012 and 2016, 1849 CVD-free women from the Mexican Teachers' Cohort responded to questions on family incarceration from the Life Stressor Checklist. Perceived stress and hair cortisol levels were measured in a subset of participants. Carotid intima-media thickness was measured, and carotid atherosclerosis was determined in all participants. We used multivariable quantile, linear, and logistic regression models to evaluate the association between family member incarceration, stress, and subclinical CVD.Results. Among women with a mean age of 49.7 years (SD ±5.2), 15.3% reported family member incarceration. We found that both perceived stress and hair cortisol levels were significantly higher in women with an incarcerated family member relative to women without one. After multivariable adjustment, women who reported family member incarceration had 41% (95% confidence interval = 1.04, 2.00) higher odds of carotid atherosclerosis compared with those who did not.Conclusions. Family member incarceration was associated with robust markers of stress and cardiovascular risk. Mass incarceration may have a long-lasting impact on physical health of affected families.

International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci

The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations.

Inflammation and post-traumatic stress disorder

While post-traumatic stress disorder (PTSD) is currently diagnosed based solely on classic psychological and behavioral symptoms, a growing body of evidence has highlighted a link between this disorder and alterations in the immune and inflammatory systems. Epidemiological studies have demonstrated that PTSD is associated with significantly increased rates of physical comorbidities in which immune dysregulation is involved, such as metabolic syndrome, atherosclerotic cardiovascular disease, and autoimmune diseases. In line with this, a number of blood biomarker studies have reported that compared to healthy controls, individuals with PTSD exhibit significantly elevated levels of proinflammatory markers, such as interleukin-1β, interleukin-6, tumor necrosis factor-α, and C-reactive protein. Moreover, various lines of animal and human research have suggested that inflammation is not only associated with PTSD but also can play an important role in its pathogenesis and pathophysiology. In this review, we first summarize evidence suggestive of increased inflammation in PTSD. We then examine findings that suggest possible mechanisms of inflammation in this disorder in terms of two different but interrelated perspectives: putative causes of increased proinflammatory activities and potential consequences that inflammation generates. Given that there is currently a dearth of treatment options for PTSD, possibilities of new therapeutic approaches using pharmacological and non-pharmacological treatments/interventions that have anti-inflammatory effects are also discussed. Despite the increasing attention given to the inflammatory pathology of PTSD, there remains much to be elucidated, including more detailed mechanisms of inflammation, potential usefulness of inflammatory biomarkers as diagnostic and prognostic markers, and efficacy of novel treatment strategies targeting inflammation.

Estimating the risk of PTSD in recent trauma survivors: results of the International Consortium to Predict PTSD (ICPP)

A timely determination of the risk of post-traumatic stress disorder (PTSD) is a prerequisite for efficient service delivery and prevention. We provide a risk estimate tool allowing a calculation of individuals' PTSD likelihood from early predictors. Members of the International Consortium to Predict PTSD (ICPP) shared individual participants' item-level data from ten longitudinal studies of civilian trauma survivors admitted to acute care centers in six countries. Eligible participants (N=2,473) completed an initial clinical assessment within 60 days of trauma exposure, and at least one follow-up assessment 4-15 months later. The Clinician-Administered PTSD Scale for DSM-IV (CAPS) evaluated PTSD symptom severity and diagnostic status at each assessment. Participants' education, prior lifetime trauma exposure, marital status and socio-economic status were assessed and harmonized across studies. The study's main outcome was the likelihood of a follow-up PTSD given early predictors. The prevalence of follow-up PTSD was 11.8% (9.2% for male participants and 16.4% for females). A logistic model using early PTSD symptom severity (initial CAPS total score) as a predictor produced remarkably accurate estimates of follow-up PTSD (predicted vs. raw probabilities: r=0.976). Adding respondents' female gender, lower education, and exposure to prior interpersonal trauma to the model yielded higher PTSD likelihood estimates, with similar model accuracy (predicted vs. raw probabilities: r=0.941). The current model could be adjusted for other traumatic circumstances and accommodate risk factors not captured by the ICPP (e.g., biological, social). In line with their use in general medicine, risk estimate models can inform clinical choices in psychiatry. It is hoped that quantifying individuals' PTSD risk will be a first step towards systematic prevention of the disorder.