The differential effects of PTSD, MDD, and dissociation on CRP in trauma-exposed women

Prevalence of autoimmune diseases in functional neurological disorder: influence of psychiatric comorbidities and biological sex

BACKGROUND

Functional neurological disorder (FND) is a common and disabling neuropsychiatric condition, which disproportionally affects women compared with men. While the etiopathogenesis of this disorder remains elusive, immune dysregulation is emerging as one potential mechanism. To begin to understand the role of immune dysfunctions in FND, we assessed the prevalence of several common autoimmune diseases (ADs) in a large cohort of patients with FND and examined the influence of psychiatric comorbidities and biological sex.

METHODS

Using a large biorepository database (Mass General Brigham Biobank), we obtained demographic and clinical data of a cohort of 643 patients diagnosed with FND between January 2015 and December 2021. The proportion of ADs was calculated overall, by sex and by the presence of psychiatric comorbidities.

RESULTS

The overall prevalence of ADs in our sample was 41.9%, with connective tissue and autoimmune endocrine diseases being the most commonly observed ADs. Among patients with FND and ADs, 27.7% had ≥2 ADs and 8% met criteria for multiple autoimmune syndrome. Rates of ADs were significantly higher in subjects with comorbid major depressive disorder and post-traumatic stress disorder (p= 0.02). Women represented the largest proportion of patients with concurrent ADs, both in the overall sample and in the subgroups of interest (p's < 0.05).

CONCLUSIONS

This study is unique in providing evidence of an association between FND and ADs. Future studies are needed to investigate the mechanisms underlying this association and to understand whether FND is characterised by distinct dysregulations in immune response.

Post-traumatic Stress Disorder: The Influence of the Environmental Context and Analysis of Oxidative Stress and Inflammatory and Glycemic Markers in Women Living in Kurdistan Regional Government-Iraq

Background Internally displaced persons (IDP) camps are still home to a large number of female survivors of the Yazidi genocide carried out in Iraq in 2014 by the Islamic organization known as the Islamic State of Iraq and Syria (ISIS). Many of these women suffer from a persistent form of post-traumatic stress disorder (PTSD), which can last for many years. On the other hand, little is known about the intricate etiology of PTSD. Objectives In this observational cross-sectional study, the biochemical parameters, including inflammatory and oxidative stress (OXS) markers, were evaluated in two groups: the case group (women with newly diagnosed PTSD) and the control group (apparently healthy women). Furthermore, how the environment impacts the biochemical and OXS parameters of people not diagnosed with PTSD but living in IDP camps was also analyzed. Materials and methods The PTSD group (n=55, age=30.0 years) was made up of women survivors of genocide-related events living in IDP camps in the Kurdistan region of Iraq. The studied parameters in the PTSD group have been compared to two healthy control groups: (1) internal control group (n=55, age=28.1 years): healthy women living inside the IDP camps; and (2) external control group (n=55, age=28.3 years): healthy women living outside the IDP camps. The diagnosis of PTSD was conducted using a validated Kurdish version of the PTSD Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) (PCL-5) scale. Blood samples were collected to determine the level of glycated hemoglobin (HbA1c) and the concentrations of fasting serum glucose (FSG), C-reactive protein (CRP), ceruloplasmin (CP), 8-hydroxydeoxyguanosine (8-OHdG), glutathione (GSH), malondialdehyde (MDA), protein carbonyls (PC), and catalase (CAT) activity. Results Women with PTSD presented increased values of FSG (4.41%, p<0.05), HbA1c (4.74%, p<0.05), and CRP (114.29%, p<0.05), as well as increased levels of 8-OHdG (185.97%, p<0.001), CP (27.08%, p<0.001), MDA (141.97%, p<0.001), and PC (63.01%, p<0.001), besides increased CAT activity (121.5%, p<0.001), when compared with the control groups. A significant reduction of GSH (-20.33%, p<0.05) was observed in PTSD patients as compared to the external control group. In relation to the internal control group, women diagnosed with PTSD presented significantly increased levels of FSG (3.88%, p<0.05), HbA1c (2.83%, p<0.05), CRP (77.97%, p<0.05), and PC (41.3%, p<0.05), as well as increased levels of 8-OHdG (118.84%, p<0.001), CP (22.72%, p<0.001), MDA (90.67%, p<0.001), and CAT activity (55.31%, p<0.001). Healthy individuals residing in IDP camps, compared with external healthy control, presented significantly elevated levels of 8-OHdG (30.68%, p<0.001), MDA (26.91%, p<0.001), PC (15.37%, p<0.001), and CAT activity (42.62%, p<0.001). Conclusion Our findings indicate that PTSD significantly influences glycemic, inflammatory, oxidant, and antioxidant parameters, as evidenced by increased levels of FSG, HbA1C, CRP, PC, MDA, 8-OHdG, and CP, as well as increased CAT activity and a reduced GSH concentration in the PTSD group in comparison to the external control group. Additionally, our results suggest that the environmental context in IDP camps by itself can potentially affect oxidant and antioxidant parameters, as evidenced by the increased concentrations of 8-OHdG, MDA, and PC and increased CAT activity found in individuals not diagnosed with PTSD but living inside the camps.

Trauma Matters: Integrating Genetic and Environmental Components of PTSD

Trauma is ubiquitous, but only a subset of those who experience trauma will develop posttraumatic stress disorder (PTSD). In this review, it is argued that to determine who is at risk of developing PTSD, it is critical to examine the genetic etiology of the disorder and individual trauma profiles of those who are susceptible. First, the state of current PTSD genetic research is described, with a particular focus on studies that present evidence for trauma type specificity, or for differential genetic etiology according to gender or race. Next, approaches that leverage non-traditional phenotyping approaches are reviewed to identify PTSD-associated variants and biology, and the relative advantages and limitations inherent in these studies are reflected on. Finally, it is discussed how trauma might influence the heritability of PTSD, through type, risk factors, genetics, and associations with PTSD symptomology.

Predicting Fear Extinction in Posttraumatic Stress Disorder

Fear extinction is the basis of exposure therapies for posttraumatic stress disorder (PTSD), but half of patients do not improve. Predicting fear extinction in individuals with PTSD may inform personalized exposure therapy development. The participants were 125 trauma-exposed adults (96 female) with a range of PTSD symptoms. Electromyography, electrocardiogram, and skin conductance were recorded at baseline, during dark-enhanced startle, and during fear conditioning and extinction. Using a cross-validated, hold-out sample prediction approach, three penalized regressions and conventional ordinary least squares were trained to predict fear-potentiated startle during extinction using 50 predictor variables (5 clinical, 24 self-reported, and 21 physiological). The predictors, selected by penalized regression algorithms, were included in multivariable regression analyses, while univariate regressions assessed individual predictors. All the penalized regressions outperformed OLS in prediction accuracy and generalizability, as indexed by the lower mean squared error in the training and holdout subsamples. During early extinction, the consistent predictors across all the modeling approaches included dark-enhanced startle, the depersonalization and derealization subscale of the dissociative experiences scale, and the PTSD hyperarousal symptom score. These findings offer novel insights into the modeling approaches and patient characteristics that may reliably predict fear extinction in PTSD. Penalized regression shows promise for identifying symptom-related variables to enhance the predictive modeling accuracy in clinical research.

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.

The association between victimization and inflammation: A meta-analysis

BACKGROUND

To meta-analyze the existing studies examining the association of childhood and adulthood victimization with inflammation and to explore the moderating variables that affect these relationships.

METHODS

Relevant work published before 28th February 2021 was identified by searching five major databases. We analyzed the cross-sectional data extracted from cross-sectional and longitudinal studies using the random-effects model to estimate the correlation (r) as the pooled effect size and further conducted subgroup analyses and sensitivity analyses.

RESULTS

A total of 37 articles finally met the inclusion criteria, including studies for C-reactive protein (CRP) (k = 23; N_CRP = 11,780), interleukin-6 (IL-6) (k = 31; N_IL-6 = 8943), and tumor necrosis factor-alpha (TNF-α) (k = 14; N_TNF-α = 4125). Overall, victimization has a significantly positive association with inflammation, with a small effect size (r = 0.122). Specifically, effect sizes were the largest for TNF-a (r = 0.152), followed by IL-6 (r = 0.119), and CRP (r = 0.084). Additionally, the effect sizes for victimization against children were r = 0.145 (k = 6) for childhood victimization - childhood inflammation, and r = 0.139 (k = 27) for childhood victimization - adulthood inflammation, which appear to be larger than that of victimization against adults (r = 0.039; k = 2).

LIMITATIONS

Only a small number of studies on adult victimization were included. In addition, we only analyzed the cross-sectional relationship and did not have sufficient data to compare different types of victimization and single vs. multiple victimizations.

CONCLUSIONS

Victimization is associated with a heightened inflammatory response. As victimization against children may have a stronger effect than victimization against adults, prevention of victimization targeting the childhood period may be necessary. Studies with more robust methodologies (i.e., representative, longitudinal, and multi-country designs) are needed to confirm these findings and to unpack the underlying mechanisms.

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.

The Effect of Intimate Partner Violence on the Physical Health and Health-Related Behaviors of Women: A Systematic Review of the Literature

AIM

The long-term effects of intimate partner violence (IPV) on physical health outcomes and health-related behaviors are underresearched in comparison to the effects on mental health and pregnancy. This systematic review examines the recent research in this area from 2012 through 2019.

METHODS

SCOPUS, PubMed, EBSCOhost, and gray literature were searched using the key words "intimate partner violence" and "health." To meet inclusion criteria, studies needed to be original research and focus on IPV during adulthood and its effects on the physical health or health-related behaviors of women. Fifty-two studies were qualitatively analyzed, with results grouped into broad categories of effects, including cardiovascular, endocrine, infectious diseases, and health screening.

RESULTS

IPV was shown to have negative effects on physical health outcomes for women, including worsening the symptoms of menopause and increasing the risk of developing diabetes, contracting sexually transmitted infections, engaging in risk-taking behaviors including the abuse of drugs and alcohol, and developing chronic diseases and pain. It also has significant effects on human immunodeficiency virus outcomes, worsening CD4+ cell depletion. Results varied regarding the effects of IPV on cardiovascular health outcomes.

CONCLUSION

The result of this review demonstrates that women who have experienced violence and abuse are at significantly increased risk of poor health outcomes in a variety of areas and so require specialized and tailored primary care. This review highlights significant gaps in this field of research, particularly in relation to cardiovascular disease, endocrine dysfunction, and neurological symptoms and conditions. It demonstrates a need for additional long-term studies in this field to better inform the health care of women who have experienced IPV and to establish the physiological mediators of these outcomes.

Childhood betrayal trauma, dissociation, and shame impact health-related quality of life among individuals with chronic pelvic pain

BACKGROUND

High betrayal trauma (HBT), or interpersonal trauma perpetrated by someone close, is linked to dissociation and shame, while trauma perpetrated by someone less close, low betrayal trauma (LBT) is associated with post-traumatic stress disorder (PTSD).

OBJECTIVE

Child interpersonal trauma is common among women with chronic pelvic pain (CPP) and can negatively impact physical and mental health-related quality of life (HRQOL). Our study investigates unexplored connections between these variables.

PARTICIPANTS & SETTING

Survey data were analyzed from 96 English-speaking female patients with CPP at a women's health clinic (mean age = 33, 59 % White non-Hispanic, 62 % married or cohabitating, 61.5 % completed post-high school degree); prevalence of HBT and LBT were 65.2 % and 45.6 %, respectively.

METHODS

Multiple regression analyzed relationships between mental and physical HRQOL and dissociation, shame, and PTSD. Parallel mediation analyses examined indirect relationships between mental and physical HRQOL and exposure to childhood HBT and LBT.

RESULTS

Dissociation was related to worse physical HRQOL, while shame was related to worse physical and mental HRQOL. Dissociation and shame mediated relationships between childhood HBT and current mental (R² = 0.08, p = .01) and physical (R² = 0.11, p = .002) HRQOL. Shame, but not PTSD, mediated relationships between childhood LBT and current mental (R² = 0.14, p < .001) and physical (R² = 0.16, p < .001) HRQOL.

CONCLUSIONS

Our study provides preliminary evidence that dissociation and shame negatively impact HRQOL among individuals with CPP in the context of exposure to different types of childhood betrayal trauma. Replication studies to validate our results with larger samples and longitudinal designs are encouraged.

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.

C-reactive protein is related to a distinct set of alterations in resting-state functional connectivity contributing to a differential pathophysiology of major depressive disorder

BACKGROUND

Several studies in major depressive disorder (MDD) have found inflammation, especially C-reactive protein (CRP), to be consistently associated with MDD and network dysfunction. The aim was to investigate whether CRP is linked to a distinct set of resting-state functional connectivity (RSFC) alterations.

METHODS

For this reason, we investigated the effects of diagnosis and elevated blood plasma CRP levels on the RSFC in 63 participants (40 females, mean age 31.4 years) of which were 27 patients with a primary diagnosis of MDD and 36 healthy control-subjects (HC), utilizing a seed-based approach within five well-established RSFC networks obtained using fMRI.

RESULTS

Of the ten network pairs examined, five showed increased between-network RSFC-values unambiguously connected either to a diagnosis of MDD or elevated CRP levels. For elevated CRP levels, increased RSFC between DMN and AN was found. Patients showed increased RSFC within DMN areas and between the DMN and ECN and VAN, ECN and AN and AN and DAN.

CONCLUSIONS

The results of this study show dysregulated neural circuits specifically connected to elevated plasma CRP levels and independent of other alterations of RSFC in MDD. This dysfunction in neural circuits might in turn result in a certain immune-inflammatory subtype of MDD.

Correlation between Mild Traumatic Brain Injury-Induced Inflammatory Cytokines and Emotional Symptom Traits: A Systematic Review

Both mild traumatic brain injuries (mTBI) and systemic injuries trigger a transient neuroinflammatory response that result in similar clinical outcome. The ensuing physical, cognitive, and emotional symptoms fail to subside in approximately 15–20% of the concussed population. Emotional impairments, particularly depression, anxiety, and post-traumatic stress disorder (PTSD), are commonly associated with poor recovery following mTBI. These emotional impairments also have a significant neuroinflammatory component. We hypothesized that the inflammatory cytokines seen in mTBI patients with emotional symptoms would coincide with those commonly seen in patients with emotional symptoms without mTBI. A systematic review was conducted to identify the most common neuroinflammatory cytokines in the mTBI population with psychological symptoms (depression, anxiety, PTSD). The electronic databases EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), PUBMED, and PSYCINFO were searched from data inception to 31 August 2021. A systematic screening approach was employed from screening to data analysis. A total of 994 articles were screened, 108 were selected for full article review, and 8 were selected for data analysis. The included studies consisted of 875 patients of which 81.3% were male. The mean sample size of patients with at least one mTBI was 73.8 ± 70.3 (range, 9–213), with a mean age of 33.9 ± 4.8 years. The most common cytokines associated with poor psychological outcomes involving PTSD and/or depression in the chronic mTBI population were IL-6, TNFα, IL-10, and CRP.

Split-Second Unlearning: Developing a Theory of Psychophysiological Dis-ease

Psychophysiological “stress” underpins many conditions including anxiety, depression, phobias, chronic fatigue syndrome and non-specific musculoskeletal pain such as fibromyalgia. In this article we develop an understanding of chronic psychophysiological stress from a psychological educational perspective, by drawing on supporting evidence that significant emotional events in early life (traumatic and benign) can influence health and well-being later in life. We suggest that traumatic events instigate psychophysiological “stress” responses and the formation of emotional memory images (EMIs) within very short time frames, i.e., “split-second learning.” Once formed these emotional memories are triggered in daily living “re-playing” psychophysiological stress responses, resulting in chronic psychophysiological “dis-ease.” We describe a novel therapeutic approach to scan clients for mannerisms signifying a subconscious “freeze-like” stress response that involves the client as a curious observer within their own experience, feeding back the non-verbal cues as they arrive in the moment. By breaking down the observable fragments of their split-second Pavlovian response to the trigger, clients can detach their EMI from the psychophysiology stress response, i.e., “split-second unlearning.” Our split-second unlearning model recognizes the EMI as a barrier to moving forward and needs to be unlearned before the client can become naturally adaptive again. We argue that this approach places the client at the center of the work without the need of getting bogged down in a life-long narrative.

Childhood trauma, dissociation, alexithymia, and anger in people with autoimmune diseases: A mediation model

BACKGROUND

Despite research linking dissociation, alexithymia, and anger with childhood trauma and ADs, the investigation addressing the relationships between the potential mediators has not yet been established within the literature.

OBJECTIVE

The present study examined the relationship between childhood trauma and autoimmune disorders, using a multiple mediation model that included dissociation, alexithymia, and anger as hypothesized mediators.

PARTICIPANTS AND SETTING

306 autoimmune patients and 292 self-declared healthy controls were included in the study. They completed self-report questionnaires regarding childhood abuse, alexithymia, dissociation, and anger.

METHODS

Multiple mediation analysis was conducted to investigate the study's proposed model.

RESULTS

The results of the Structural Equation Model (SEM) suggest an indirect relationship between childhood trauma and autoimmune disorders, mediated by dissociation [z = 4.57, p < .01, β = 0.19, 90% CI (0.08-0.10)], alexithymia [z = 10.74, p < .01, β = 0.43, 90% CI (0.08-0.10)], but not by anger [z = 1.58, p = .11, 90% CI (0.08-0.10)].

CONCLUSIONS

These findings are in line with previous studies that show associations between childhood trauma, dissociation, alexithymia, and ADs. They indicate that mental health professionals and medical doctors should assess childhood trauma in autoimmune patients. They also should consider the possible maintaining role of dissociation and alexithymia in the treatment of autoimmune diseases.

Dissociation in SLE: A part of lupus fog?

INTRODUCTION

Lupus fog is ill-defined. We aimed to study whether lupus fog is the result of dissociation by studying the prevalence of dissociation and dissociative fog in patients with SLE and neuropsychiatric manifestations of inflammatory and non-inflammatory origin.

METHODS

Patients visiting the tertiary referral center for neuropsychiatric systemic lupus erythematosus (NPSLE) of the LUMC between 2007-2019 were included. Patients were classified as having neuropsychiatric symptoms of inflammatory or non-inflammatory origin. Dissociation was studied using the Dissociative Experience Scale-II (DES), in which the presence of 28 dissociative symptoms is rated (0-100% of the time), of which one question assesses the presence of a dissociative fog directly. Average scores are calculated and scores ≥ 25 are considered indicative of a dissociative disorder. A score of ≥ 30 on question 28 (dissociative fog) was considered indicative for the presence of a fog. Summary scores in the general adult population range from 4.4 to 14. Multiple regression analysis (MRA) was performed to study the association between inflammatory neuropsychiatric symptoms and dissociation. DES results are presented as median (range) and MRA as B and 95% confidence interval (CI).

RESULTS

DES questionnaires were available for 337 patients, of which 69 had an inflammatory NPSLE phenotype (20%). Mean age in the total study population was 43 ± 14 years and the majority was female (87%). The median dissociation score was 7.1 (0-75) and did not differ between patients with neuropsychiatric symptoms of inflammatory or non-inflammatory origin (B: -0.04 (95% CI: -0.17; 0.09)). 35 patients (10%) had a score indicative of a dissociative disorder. The most common type of dissociation was absorption/imagination. 43 patients (13%) reported a dissociative fog.

DISCUSSION

In most patients with SLE and neuropsychiatric symptoms, dissociative symptoms are within normal range, regardless of underlying etiology. Dissociative fog is present, but uncommon. Lupus fog is most likely not associated with dissociation.

Inflammation and early life stress: An updated review of childhood trauma and inflammatory markers in adulthood

Inflammation, as a neurobiological consequence of childhood trauma, has frequently been reported across research, however, recent investigations suggest this relationship may be dependent on specificities such as type of trauma, type of inflammatory marker, and additional mediatory variables - such as body mass index (BMI), age, and sex. As an updated version of a previous review by Baumeister et al., the current review comprised a search of PubMed, which identified 37 articles that collectively assessed 4 inflammatory markers (CRP, IL-6, TNFα and IL-1β). A review of the studies revealed predominantly non-significant associations between childhood trauma and elevated levels of all inflammatory markers in adulthood. However, in line with previous research, discrepancies in significance arose when considering type of trauma, type of inflammatory marker, and additional variables. Compared to neglect, abuse showed greater significant associations with elevated inflammatory markers in adulthood, though this was dependent on the individual subtypes (emotional, physical or sexual). Mediation analyses reported BMI as a significant mediator, though, when controlled for, no significant differences were found. Sex differences were reported but investigations were sparse. Future research should investigate the mediatory role of sex differences in the inflammatory effects of childhood trauma. Many studies in the review were restricted by use of the same trauma measure - the Childhood Trauma Questionnaire. To assess greater variety of trauma types, future studies should utilize other standardized measures to explore these avenues.

IL-6 and hsCRP in Somatic Symptom Disorders and related disorders

Interleukin 6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) are biomarkers of systemic low-grade inflammation (SLI) in depression and anxiety. The question if SLI in those conditions is related to comorbid chronic medical conditions has not been resolved. DSM-5 Somatic symptom disorders and related disorders (SSRD) are conditions with serious distress related to physical symptoms as main criterion. They can occur in patients with medically unexplained symptoms (MUS) and in patients with known comorbid chronic medical conditions. Often, comorbid depression and anxiety are present. SSRDs offer the opportunity to explore the role of SLI in relation to mental distress, including trauma, MUS, chronic medical conditions and comorbid mental disorder.

AIM

We hypothesized that increased IL-6 and hsCRP may be directly linked to SLI in SSRD, and that comorbid chronic medical conditions, childhood trauma, current stress and comorbid depression and anxiety may be risk factors that account for some of the variance of SLI in SSRD.

METHODS

We explored these relationships in a large sample of 241 consecutive outpatients with SSRD.

RESULTS

Mean hsCRP level was 3.66 ​mg/l, and mean IL-6 level was 3.58 ​pg/ml. IL-6 and hsCRP levels were associated with each other: τ ​= ​0.249, p ​< ​.001; a medium size correlation. Comorbid chronic medical conditions, adverse childhood events other than sexual trauma, and current stress levels were not associated with IL-6 or hsCRP levels.

CONCLUSION

IL-6 and hsCRP are elevated in SSRD, indicating SLI in SSRD independently of comorbid chronic medical conditions. In clinical research, elevated IL-6 and hsCRP can be used as biomarkers of SLI and can indicate risk for childhood sexual abuse in SSRD. Elevated hsCRP may be a biomarker indicating risk for comorbid depression or high pain levels in SSRD as well.

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.

Biological correlates of early life stressful events in major depressive disorder

Major depressive disorder (MDD) is the most common psychiatric disorder and responds for important psychosocial consequences. Stressful life events, especially early life stress (ELS), contribute to an increased probability to develop MDD, leading in particular to severe and chronic manifestation and unfavorable treatment outcome. The association between ELS and MDD seems to have biological bases, consisting in dysregulations occurring at different levels. The aim of this narrative review is to propose an overview of the literature ranging from genetic, epigenetic, expression and protein to neuroimaging correlates underlying this relationship. A search on Pubmed of studies assessing biological correlates of ELS in MDD development, focusing on human studies conducted in both peripheral and brain tissues, was performed. Evidence indicated that the hypothalamic-pituitary-adrenal (HPA) axis and the serotonergic, dopaminergic, neurotrophin and oxytocin systems might play a role in the mediation between ELS and MDD. The most consistent results were found for genetic and epigenetic studies and indicated a joint involvement of the systems mentioned. Expression studies are less numerous and point to an involvement of stress-related systems. Concerning protein studies, the main mediators are markers related to the inflammatory and immune systems. Neuroimaging studies aiming at evaluating brain alterations connecting ELS and MDD in relation to biomarkers indicated the hippocampus, the amygdala and the frontal cortex as important anatomical mediators. These findings can build the bases for future research and clinical interventions; indeed, the clarification of biological mechanisms mediating the relationship between ELS and MDD can lead to new and individualized preventive and therapeutic possibilities.

Biomarkers of Pathological Dissociation: A Systematic Review

Pathological dissociation is a severe, debilitating and transdiagnostic psychiatric symptom. This review identifies biomarkers of pathological dissociation in a transdiagnostic manner to recommend the most promising research and treatment pathways in support of the precision medicine framework. A total of 205 unique studies that met inclusion criteria were included. Studies were divided into four biomarker categories, namely neuroimaging, psychobiological, psychophysiological and genetic biomarkers. The dorsomedial and dorsolateral prefrontal cortex, bilateral superior frontal regions, (anterior) cingulate, posterior association areas and basal ganglia are identified as neurofunctional biomarkers of pathological dissociation and decreased hippocampal, basal ganglia and thalamic volumes as neurostructural biomarkers. Increased oxytocin and prolactin and decreased tumor necrosis factor alpha (TNF-α) are identified as psychobiological markers. Psychophysiological biomarkers, including blood pressure, heart rate and skin conductance, were inconclusive. For the genetic biomarker category studies related to dissociation were limited and no clear directionality of effect was found to warrant identification of a genetic biomarker. Recommendations for future research pathways and possible clinical applicability are provided.

Neuroimmune Mechanisms and Sex/Gender-Dependent Effects in the Pathophysiology of Mental Disorders

Innate and adaptive immune mechanisms have emerged as critical regulators of CNS homeostasis and mental health. A plethora of immunologic factors have been reported to interact with emotion- and behavior-related neuronal circuits, modulating susceptibility and resilience to mental disorders. However, it remains unclear whether immune dysregulation is a cardinal causal factor or an outcome of the pathologies associated with mental disorders. Emerging variations in immune regulatory pathways based on sex differences provide an additional framework for discussion in these psychiatric disorders. In this review, we present the current literature pertaining to the effects that disrupted immune pathways have in mental disorder pathophysiology, including immune dysregulation in CNS and periphery, microglial activation, and disturbances of the blood-brain barrier. In addition, we present the suggested origins of such immune dysregulation and discuss the gender and sex influence of the neuroimmune substrates that contribute to mental disorders. The findings challenge the conventional view of these disorders and open the window to a diverse spectrum of innovative therapeutic targets that focus on the immune-specific pathophenotypes in neuronal circuits and behavior. SIGNIFICANCE STATEMENT: The involvement of gender-dependent inflammatory mechanisms on the development of mental pathologies is gaining momentum. This review addresses these novel factors and presents the accumulating evidence introducing microglia and proinflammatory elements as critical components and potential targets for the treatment of mental disorders.

Enhanced conditioning of adverse memories in the mouse modified swim test is associated with neuroinflammatory changes - Effects that are susceptible to antidepressants

Deficient learning and memory are well-established pathophysiologic features of depression, however, mechanisms of the enhanced learning of aversive experiences associated with this disorder are poorly understood. Currently, neurobiological mechanisms of enhanced retention of aversive memories during depression, and, in particular, their relation to neuroinflammation are unclear. As the association between major depressive disorder and inflammation has been recognized for some time, we aimed to address whether neuroinflammatory changes are involved in enhanced learning of adversity in a depressive state. To study this question, we used a recently described mouse model of enhanced contextual conditioning of aversive memories, the modified forced swim model (modFST). In this model, the classic two-day forced swim is followed by an additional delayed session on Day 5, where increased floating behaviour and upregulated glycogen synthase kinase-3 (GSK-3) are context-dependent. Here, increased time spent floating on Day 5, a parameter of enhanced learning of the adverse context, was accompanied by hypercorticosteronemia, increased gene expression of GSK-3α, GSK-3β, c-Fos, cyclooxygenase-1 (COX-1) and pro-inflammatory cytokines interleukin-1 beta (IL-1β), tumor necrosis factor (TNF), and elevated concentrations of protein carbonyl, a marker of oxidative stress, in the prefrontal cortex and hippocampus. There were significant correlations between cytokine levels and GSK-3β gene expression. Two-week administration of compounds with antidepressant properties, imipramine (7 mg/kg/day) or thiamine (vitamin B1; 200 mg/kg/day) ameliorated most of the modFST-induced changes. Thus, enhanced learning of adverse memories is associated with pro-inflammatory changes that should be considered for optimizing pharmacotherapy of depression associated with enhanced learning of aversive memories.

Stress-induced blood brain barrier disruption: Molecular mechanisms and signaling pathways

Stress is a nonspecific response to a threat or noxious stimuli with resultant damaging consequences. Stress is believed to be an underlying process that can trigger central nervous system disorders such as depression, anxiety, and post-traumatic stress disorder. Though the pathophysiological basis is not completely understood, data have consistently shown a pivotal role of inflammatory mediators and hypothalamo-pituitary-adrenal (HPA) axis activation in stress induced disorders. Indeed emerging experimental evidences indicate a concurrent activation of inflammatory signaling pathways and not only the HPA axis, but also, peripheral and central renin-angiotensin system (RAS). Furthermore, recent experimental data indicate that the HPA and RAS are coupled to the signaling of a range of central neuro-transmitter, -mediator and -peptide molecules that are also regulated, at least in part, by inflammatory signaling cascades and vice versa. More recently, experimental evidences suggest a critical role of stress in disruption of the blood brain barrier (BBB), a neurovascular unit that regulates the movement of substances and blood-borne immune cells into the brain parenchyma, and prevents peripheral injury to the brain substance. However, the mechanisms underlying stress-induced BBB disruption are not exactly known. In this review, we summarize studies conducted on the effects of stress on the BBB and integrate recent data that suggest possible molecular mechanisms and signaling pathways underlying stress-induced BBB disruption. Key molecular targets and pharmacological candidates for treatment of stress and related illnesses are also summarized.

Inflammation and Trauma-Related Psychopathology in Syrian and Iraqi Refugees

Refugees experience high rates of post-traumatic stress disorder (PTSD), anxiety, and depression due to exposure to civilian war trauma and forced migration. Inflammatory products may offer viable biological indicators of trauma-related psychopathology in this cohort, promoting rapid and objective assessment of psychopathology. Incoming Syrian and Iraqi refugees (n = 36) ages 18-65 completed self-report measures of PTSD, anxiety, and depression and provided saliva samples during an assessment at a primary care clinic within the first month of resettlement in the United States. Interleukin 1β (IL-1β) and C-reactive protein (CRP) differentially correlated with symptom severity by domain, and there was a non-significant trend for sex moderating the relation between inflammation and PTSD symptoms. Our findings show unique relations between trauma-related psychopathology and inflammation. There is a need for further research in diverse ethnic cohorts with differential trauma exposures for inflammation to be considered a biological indicator of psychopathology.

Trauma exposure and stress-related disorders in African-American women with diabetes mellitus

OBJECTIVE

The purpose of the study was to assess demographic features, rates of trauma exposure, prevalence of post-traumatic stress and depressive symptoms in a group of urban, low-income, African-American women with type 1 or type 2 diabetes mellitus.

RESEARCH DESIGN AND METHODS

We conducted a survey of (n = 290) low-income, African-American women seeking care in the diabetes clinic of an urban hospital and collected data on the demographic characteristics, childhood and nonchildhood abuse trauma exposure, and the severity of post-traumatic stress and depressive symptoms using the Post-traumatic Stress Disorder (PTSD) Symptom Scale (PSS) and the Beck Depression Inventory (BDI). In a subset of women with type 2 diabetes (n = 96), we assessed haemoglobin A1c to examine the relationship between psychopathology and glycaemic control.

RESULTS

Of the overall sample, 61.7% reported exposure to trauma in their lifetime, and 30.4% and 29.3% had current PTSD and MDD, respectively. Exposure to both childhood and nonchildhood abuse trauma was associated with an increased PTSD and depressive symptom severity (P's < .05). PTSD diagnosis, but not depression, was associated with increased haemoglobin A1c (P = .002).

CONCLUSIONS

These data document high levels of trauma exposure, PTSD and depressive symptoms in diabetic African-American women treated in a specialty clinic of an urban hospital setting. Furthermore, these data indicate that the presence of PTSD is negatively associated with glycaemic control.