Neuropattern: a new translational tool to detect and treat stress pathology I. Strategical consideration

Stress and Pain. Predictive (Neuro)Pattern Identification for Chronic Back Pain: A Longitudinal Observational Study

Introduction

Low back pain (LBP) leads to considerable impairment of quality of life worldwide and is often accompanied by psychosomatic symptoms.

Objectives

First, to assess the association between stress and chronic low back pain (CLBP) and its simultaneous appearance with fatigue and depression as a symptom triad. Second, to identify the most predictive stress-related pattern set for CLBP for a 1-year diagnosis.

Methods

In a 1-year observational study with four measurement points, a total of 140 volunteers (aged 18–45 years with intermittent pain) were recruited. The primary outcomes were pain [characteristic pain intensity (CPI), subjective pain disability (DISS)], fatigue, and depressive mood. Stress was assessed as chronic stress, perceived stress, effort reward imbalance, life events, and physiological markers [allostatic load index (ALI), hair cortisol concentration (HCC)]. Multiple linear regression models and selection procedures for model shrinkage and variable selection (least absolute shrinkage and selection operator) were applied. Prediction accuracy was calculated by root mean squared error (RMSE) and receiver-operating characteristic curves.

Results

There were 110 participants completed the baseline assessments (28.2 ± 7.5 years, 38.1% female), including HCC, and a further of 46 participants agreed to ALI laboratory measurements. Different stress types were associated with LBP, CLBP, fatigue, and depressive mood and its joint occurrence as a symptom triad at baseline; mainly social-related stress types were of relevance. Work-related stress, such as “excessive demands at work”[b = 0.51 (95%CI -0.23, 1.25), p = 0.18] played a role for upcoming chronic pain disability. “Social overload” [b = 0.45 (95%CI -0.06, 0.96), p = 0.080] and “over-commitment at work” [b = 0.28 (95%CI -0.39, 0.95), p = 0.42] were associated with an upcoming depressive mood within 1-year. Finally, seven psychometric (CPI: RMSE = 12.63; DISS: RMSE = 9.81) and five biomarkers (CPI: RMSE = 12.21; DISS: RMSE = 8.94) could be derived as the most predictive pattern set for a 1-year prediction of CLBP. The biomarker set showed an apparent area under the curve of 0.88 for CPI and 0.99 for DISS.

Conclusion

Stress disrupts allostasis and favors the development of chronic pain, fatigue, and depression and the emergence of a “hypocortisolemic symptom triad,” whereby the social-related stressors play a significant role. For translational medicine, a predictive pattern set could be derived which enables to diagnose the individuals at higher risk for the upcoming pain disorders and can be used in practice.

Three-way interaction effects of early life stress, positive parenting and FKBP5 in the development of depressive symptoms in a general population

FKBP5 gene–environment interaction (cG × E) studies have shown diverse results, some indicating significant interaction effects between the gene and environmental stressors on depression, while others lack such results. Moreover, FKBP5 has a potential role in the diathesis stress and differential susceptibility theorem. The aim of the present study was to evaluate whether a cG × E interaction effect of FKBP5 single-nucleotide polymorphisms (SNPs) or haplotype and early life stress (ELS) on depressive symptoms among young adults was moderated by a positive parenting style (PASCQ^pos), through the frameworks of the diathesis stress and differential susceptibility theorem. Data were obtained from the Survey of Adolescent Life in Västmanland Cohort Study, including 1006 participants and their guardians. Data were collected during 2012, when the participants were 13 and 15 years old (Wave I: DNA), 2015, when participants were 16 and 18 years old (Wave II: PASCQ^pos, depressive symptomology and ELS) and 2018, when participants were 19 and 21 years old (Wave III: depressive symptomology). Significant three-way interactions were found for the FKBP5 SNPs rs1360780, rs4713916, rs7748266 and rs9394309, moderated by ELS and PASCQ^pos, on depressive symptoms among young adults. Diathesis stress patterns of interaction were observed for the FKBP5 SNPs rs1360780, rs4713916 and rs9394309, and differential susceptibility patterns of interaction were observed for the FKBP5 SNP rs7748266. Findings emphasize the possible role of FKBP5 in the development of depressive symptoms among young adults and contribute to the understanding of possible differential susceptibility effects of FKBP5.

Towards an understanding of neurophysiological self-regulation in early childhood: A heuristic and a new approach

Self-regulation in early childhood encompasses both "top down," volitional processes, as well as the "bottom up" activity of three neurophysiological systems: the parasympathetic nervous system (PNS), the sympathetic nervous system (SNS), and the hypothalamic-pituitary-adrenal (HPA) axis. In this paper we briefly review the structure, function, and early development of each of these systems and then explain why neurophysiological self-regulation is most accurately defined as a function of their joint activity. We note that while there are a number of predictive models that employ this definition, the field would benefit from a straightforward heuristic and aligned methods of visualization and analysis. We then present one such heuristic, which we call neurophysiological space, and outline how it may facilitate a new, collaborative approach to building a better understanding of self-regulation in early childhood. We conclude with a presentation of early education as one setting in which our heuristic and methods could be applied.

Investigating associations between momentary stress and cortisol in daily life: What have we learned so far?

Since cortisol measurement in saliva has been established, it has been used as an indicator of stress-related hypothalamic-pituitary-adrenocortical axis activity. Concurrent development of methodological frameworks such as ambulatory assessment, ecological momentary assessment, and experience sampling have provided opportunities to combine both approaches in daily life research. The current review provides a summary of basic methodological principles and recommendations, as well as abstracts of findings of studies investigating momentary associations between stress and cortisol in daily life with an emphasis on within-subject associations (i.e. average covariance in repeated momentary assessments of stress and cortisol, and individual-specific deviations from the average covariance). Methodological challenges related to stress measurement, sampling principles, and appropriate statistical modeling are discussed, followed by a description of the historical development of studies on within-subject associations between momentary daily life stress and cortisol. The review concludes with a discussion of controversial methodological characteristics of these studies regarding operationalizations of stress, compliance, timing and frequency of stress and cortisol sampling, and reporting of effect sizes. Future research in this area would benefit from automated cortisol assessment, broadening of the scope of stress response measures, use of advanced statistical models that better account for dynamics in the stress process in daily life, and attempts to replicate findings. While previous studies of momentary stress and concurrent cortisol assessments have reliably confirmed some fundamental predictions from stress theory in daily life, future studies should aim at providing progress by testing innovative research questions and utilizing new technological developments.

Genetic variation of the mineralocorticoid receptor gene (MR, NR3C2) is associated with a conceptual endophenotype of "CRF-hypoactivity"

Recently, the "conceptual endophenotype" approach has been proposed as a means to identify subgroups of patients affected by stress-related psychiatric disorders. Conceptual endophenotypes consist of patterns of psychological, biological, and symptomatic elements. We studied a sample of patients seeking help for psychosomatic and stress-related disorders (total N = 469), who were evaluated with a diagnostic instrument that integrates psychological and biological data to derive 13 endophenotypes, or Neuropattern. The goal of this study was to explore associations between common variations of the mineralocorticoid receptor gene (MR, NR3C2), and the 13 conceptual endophenotypes of Neuropattern, as well as with the respective biological and symptom measures. A common haplotype of the MR, comprised of two functional single nucleotide polymorphism (rs2070951 G/C & rs5522 A/G), was associated with the conceptual endophenotype CRF-hypoactivity, characterized by low cortisol levels at awakening and a symptom constellation often observed in atypical depression. Homozygous carriers of the G-A haplotype (haplotype 1), previously associated with reduced dispositional optimism, increased levels of rumination and higher risk for depression, more frequently endorsed this Neuropattern. In addition to the overall association between MR variation and CRF hypoactivity, we observed in the whole sample significant associations between MR haplotypes and cortisol awakening response patterns, as well as with symptoms that characterize the CRF hypoactivity endophenotype. If replicated, MR haplotype 1 might serve as a vulnerability marker for a disorder class characterized in biological terms by reduced cortisol levels, and in terms of symptom constellation by features often observed in atypical depression.

How to determine whether conceptual endophenotypes can improve clinical outcomes in patients suffering from major depression: An exploratory approach

Depression is a complex mental health disorder, resulting in a high degree of disability. Since symptom constellation, course, and outcome are heterogeneous in these patients, current research initiatives are striving to establish stratified diagnostic and treatment approaches. In the past two decades, Dirk Hellhammer and his team introduced Neuropattern, a new diagnostic concept, which is based on conceptual endophenotypes of the stress response network. We explore how to use this concept in clinical practice in order to ultimately determine whether it brings any value over standard care. In view of the novelty of the concept and the difficulties dealing with such a concept at a practical level, it was necessary to initiate an exploratory study to determine key factors for planning future clinical trials. We report results and knowledge gained from an exploratory single-site study investigating the use and potential benefits of Neuropattern in standard care. Inpatients (ICD-10 diagnosis F32, F33; Nö=ö178) were allocated to either treatment as usual (standard group, SG) or a novel Neuropattern oriented exploratory treatment (intervention group, IG). Symptom severity was assessed with psychometric tests at admission to hospital, during the first six weeks, and upon discharge from the hospital. In addition, direct and indirect costs were assessed for the 3-month-intervals prior to and after the hospital stay. Compared to the SG, depression scores of patients in the IG showed a faster decline once psychotherapeutic and pharmacological treatment were based on an individualized explanatory model. The patients in the IG with an F33 diagnosis showed a more pronounced reduction of depression severity during the stay in the hospital and a stronger and quicker reduction of general symptom severity. Comparing the average depression scores at the start of the study and after six weeks, symptom severity was reduced in all Neuropattern groups. Some limitations of the study have to be mentioned: The study was not blinded, was single-site, included highly depressed inpatients only, and was conducted for no longer than 8 months. The results highlight some important issues regarding taking the Neuropattern approach to the bedside and researching its efficacy and effectiveness to support personalized treatments in clinical care.

From serendipity to clinical relevance: How clinical psychology and neuroscience converged to illuminate psychoneuroendocrinology

Dirk Hellhammer and his colleagues have played a major role in creating the field of psychoneuroendocrinology from their roots in psychology. In this review, using examples from the history of the McEwen laboratory and neuroscience and neuroendocrinology colleagues, I summarize my own perspective as to how the fields of neuroscience and neuroendocrinology have contributed to psychoneuroendocrinology and how they converged with the contributions from Dirk Hellhammer and his colleagues.

Importance of the brain corticosteroid receptor balance in metaplasticity, cognitive performance and neuro-inflammation

Bruce McEwen's discovery of receptors for corticosterone in the rat hippocampus introduced higher brain circuits in the neuroendocrinology of stress. Subsequently, these receptors were identified as mineralocorticoid receptors (MRs) that are involved in appraisal processes, choice of coping style, encoding and retrieval. The MR-mediated actions on cognition are complemented by slower actions via glucocorticoid receptors (GRs) on contextualization, rationalization and memory storage of the experience. These sequential phases in cognitive performance depend on synaptic metaplasticity that is regulated by coordinate MR- and GR activation. The receptor activation includes recruitment of coregulators and transcription factors as determinants of context-dependent specificity in steroid action; they can be modulated by genetic variation and (early) experience. Interestingly, inflammatory responses to damage seem to be governed by a similarly balanced MR:GR-mediated action as the initiating, terminating and priming mechanisms involved in stress-adaptation. We conclude with five questions challenging the MR:GR balance hypothesis.

Conceptual endophenotypes: A strategy to advance the impact of psychoneuroendocrinology in precision medicine

Psychobiological research has generated a tremendous amount of findings on the psychological, neuroendocrine, molecular and environmental processes that are directly relevant for mental and physical health, but have overwhelmed our capacity to meaningfully absorb, integrate, and utilize this knowledge base. Here, we reflect about suitable strategies to improve the translational success of psychoneuroendocrinological research in the era of precision medicine. Following a strategy advocated by the National Research Council and the tradition of endophenotype-based research, we advance here a new approach, termed "conceptual endophenotypes". We define the contextual and formal criteria of conceptual endophenotypes, outline criteria for filtering and selecting information, and describe how conceptual endophenotypes can be validated and implemented at the bedside. As proof-of-concept, we describe some of our findings from research that has adopted this approach in the context of stress-related disorders. We argue that conceptual endophenotypes engineer a bridge between the bench and the bedside. This approach readily lends itself to being continuously developed and implemented. Recent methodological advances, including digital phenotyping, machine learning, grassroots collaboration, and a learning healthcare system, may accelerate the development and implementation of this conceptual endophenotype approach.

Cortisol stress reactivity across psychiatric disorders: A systematic review and meta-analysis

The hypothalamus-pituitary-adrenal (HPA) axis and its end product cortisol are essential for an adequate response to stress. Considering the role of stress as a risk factor for psychiatric disorders, it is not surprising that cortisol stress reactivity has frequently been investigated in patients versus healthy individuals. However, the large heterogeneity in measures of the cortisol stress response has hampered a systematic evaluation of the evidence. We here report of a systematic literature review and meta-analysis on cortisol reactivity to psychosocial stress across psychiatric disorders. Original data from authors were obtained to construct standardized cortisol outcomes (the areas under the curve with respect to increase (AUCi) and ground (AUCg)) and to examine the influence of sex and symptomatic state on cortisol stress reactivity. Fourteen studies on major depressive disorder (MDD) (n=1129), 9 on anxiety disorders (n=732, including social anxiety disorder (SAD), posttraumatic stress disorder, panic disorder and mixed samples of anxiety disorders) and 4 on schizophrenia (n=180) were included that used the Trier Social Stress Test or an equivalent psychosocial stress task. Sex-dependent changes in stress reactivity were apparent in MDD and anxiety disorders. Specifically, women with current MDD or an anxiety disorder exhibited a blunted cortisol stress response, whereas men with current MDD or SAD showed an increased cortisol response to psychosocial stress. In individuals with remitted MDD, altered cortisol stress reactivity was less pronounced in women and absent in men. For schizophrenia, cortisol stress reactivity was blunted in both men and women, but the number of studies was limited and showed evidence for publication bias. These findings illustrate that sharing individual data to disentangle the effects of sex, symptom levels and other factors is essential for further understanding of the alterations in cortisol stress reactivity across psychiatric disorders.

The role of early adversity and recent life stress in depression severity in an outpatient sample

Pre-, peri-, and postnatal stress have frequently been reported to be associated with negative health outcomes during adult life. However, it is unclear, if these factors independently predict mental health in adulthood. We estimated potential associations between reports of pre-, peri-, and postnatal stress and depression severity in outpatients (N = 473) diagnosed with depression, anxiety or somatoform disorders by their family physician. We retrospectively assessed pre-, peri-, and postnatal stress and measured depression severity as well as recent life stress using questionnaires. First, we estimated if depression severity was predicted by pre-, peri- and/or postnatal stress using multiple regression models. Second, we compared pre- and postnatal stress levels between patient subgroups of different degrees of depression severity, performing multilevel linear modeling. Third, we analyzed if an association between postnatal stress and current depression severity was mediated by recent life stress. We found no associations of pre-, or perinatal stress with depression severity (all p > 0.05). Higher postnatal stress was associated with higher depression severity (p < 0.001). Patients with moderately severe and severe depression reported higher levels of postnatal stress as compared to patients with none to minimal, or mild depression (all p < 0.05). Mediation analysis revealed a significant indirect effect via recent life stress of the association between postnatal stress and depression severity (p < 0.001). In patients diagnosed for depression, anxiety, and/or somatoform disorders, postnatal but neither pre- nor perinatal stress predicted depression severity in adult life. This association was mediated by recent life stress.

Frequency of Perceived Poststress Symptoms in Inpatients, Outpatients and Healthy Controls: The Role of Perceived Exhaustion and Stress

BACKGROUND

Poststress symptoms occur as a consequence of stress, most commonly during leisure periods such as weekends and vacations. However, the prevalence and the pathological mechanisms of poststress symptoms are poorly understood.

METHODS

Here, we compared the frequency of poststress symptoms in healthy controls (n = 984), outpatients (n = 420), and inpatients (n = 101). In outpatients, demographic factors, psychosocial stress, and perceived exhaustion were tested as predictors of poststress symptoms with multivariate regression analysis. Poststress symptoms and perceived exhaustion were assessed using 2 Neuropattern Questionnaires (the NPQ - Patient Questionnaire and the NPQ - Symptom List), and psychosocial stress was evaluated using the Patient Health Questionnaire (PHQ).

RESULTS

Poststress symptoms appeared in 2.9% of healthy controls, 20.0% of outpatients, and 34.7% of inpatients. Predictors were educational level, psychosocial stress, and perceived exhaustion. Poststress symptoms differed primarily between exhausted (75.0%) and nonexhausted patients (25.0%).

CONCLUSION

Poststress symptoms are rather common in clinical populations, and they are primarily associated with the degree of perceived exhaustion. Preliminary evidence suggests that poststress symptoms are possibly related to depletion of norepinephrine stores, which may facilitate a stratified preventive and therapeutic treatment of these subjects.

Stress and Depression: a Crucial Role of the Mineralocorticoid Receptor

Cortisol and corticosterone act on the appraisal process, which comprises the selection of an appropriate coping style and the encoding of the experience for storage in the memory. This action exerted by the stress hormones is mediated by mineralocorticoid receptors (MRs), which are expressed abundantly in the limbic circuitry, particularly in the hippocampus. Limbic MR is down-regulated by chronic stress and during depression but induced by antidepressants. Increased MR activity inhibits hypothalamic-pituitary-adrenal axis activity, promotes slow wave sleep, reduces anxiety and switches circuit connectivity to support coping. Cortisol and emotion-cognition are affected by MR gene haplotypes based on rs5522 and rs2070951. Haplotype 1 (GA) moderates the effects of (early) life stressors, reproductive cycle and oral contraceptives. MR haplotype 2 (CA) is a gain of function variant that protects females against depression by association with an optimistic, resilient phenotype. Activation of MR therefore may offer a target for alleviating depression and cognitive dysfunction. Accordingly, the MR agonist fludrocortisone was found to enhance the efficacy of antidepressants and to improve memory and executive functions in young depressed patients. In conclusion, CORT coordinates via MR the networks underlying how an individual copes with stress, and this action is complemented by the widely distributed lower affinity glucocorticoid receptor (GR) involved in the subsequent management of stress adaptation. In this MR:GR regulation, the MR is an important target for promoting resilience.

Lack of Breastfeeding: A Potential Risk Factor in the Multifactorial Genesis of Borderline Personality Disorder and Impaired Maternal Bonding

Borderline personality disorder (BPD) is characterized by a pattern of intense but unstable interpersonal relationships. These interpersonal dysfunctions may originate from impaired bonding and attachment that is determined during early life. Remarkably, it has been reported that the quality of mother-infant relationship is influenced by the feeding mode. Thus, bottle feeding instead of breastfeeding and possible lack of maternal bonding-related behavior may increase the risk for later psychopathology and attachment problems as seen in BPD. A total of 100 BPD patients and 100 matched healthy controls underwent semistructured interviews, based on retrospective information about early risk factors and breastfeeding during infancy. The authors' analyses revealed that BPD patients were significantly less breastfed compared to healthy controls (no breastfeeding in BPD: 42.4%; no breastfeeding in controls: 18.2%; p < .001). The BPD diagnosis was significantly predicted by the variable "no breastfeeding" (p < .001; odds ratio [OR] = 3.32; confidence interval [CI] [1.74, 6.34]), even after adjustment for childhood trauma and several confounding factors (p = .001). The variable "no breastfeeding" accounts for 9.1% of the variance of the BPD diagnosis and is associated with low perceived maternal bonding (p = .006). Breastfeeding may act as an early indicator of the mother-infant relationship that seems to be relevant for bonding and attachment later in life.

Subjektive Erschöpfung bei stressbezogenen Gesundheitsstörungen

Erschöpfung kennzeichnet zahlreiche psychische Störungen. Wir haben geprüft, ob die subjektive Erschöpfungsqualität ein verlässlicher Indikator für stressbezogene Gesundheitsstörungen und den daraus resultierenden direkten, indirekten und intangiblen Gesundheitskosten ist. Zur Anwendung kam eine Erschöpfungsskala (Neuropattern-Questionnaire, NPQ-S), deren Cut-off-Werte und Reliabilität anhand einer bevölkerungsrepräsentativen Stichprobe (N = 998) ermittelt wurden. Die Validität wurde bei ambulanten Patienten (N = 455) über Angaben zu psychischen Erkrankungen, gesundheitsbezogenen Kosten und strukturierten Anamnesen sowie einer berufshomogene Stichprobe mit stressbezogenen Beschwerden (N = 69) über Angaben zu Burnout und Gratifikationskrisen untersucht. Die Reliabilität und Validität der Erschöpfungsqualität konnten als gut bis sehr gut eingestuft werden. Die Ergebnisse zeigten, dass ein erhöhtes Ausmaß an Erschöpfung mit erhöhter Stressbelastung, einer erhöhten Chance für verschiedene psychische Erkrankungen sowie erhöhten Kosten (reduziertes Wohlbefinden, häufigere Therapeuten- und Arztbesuche, erhöhter Medikamentenkonsum, mehr Arbeitsunfähigkeitstage) einhergeht. Die Erschöpfungsqualität zeigt sich als störungsübergreifender Indikator und kann als ökonomisches Indikations- und Evaluationsmaß für gesundheitsförderliche Maßnahmen dienen.

Effects of genetic and early environmental risk factors for depression on serotonin transporter expression and methylation profiles

The serotonin transporter (SERT) gene-linked polymorphic region (5-HTTLPR) has been implicated in moderating the link between life stress and depression. However, respective molecular pathways of gene-environment (GxE) interaction are largely unknown. Sustained alterations in SERT gene expression profiles, possibly mediated by epigenetic modifications, are a frequent correlate of depression and may thus constitute a putative mediator of GxE interaction. Here, we aimed to investigate joint effects of 5-HTTLPR and self-reported environmental adversity throughout the lifespan (prenatal, early and recent stress/trauma) on in vivo SERT mRNA expression in peripheral blood cells. To further evaluate whether environmentally induced changes in SERT expression are mediated by epigenetic modifications, we analyzed 83 CpG sites within a 799-bp promoter-associated CpG island of the SERT gene using the highly sensitive method of bisulfite pyrosequencing. Participants were 133 healthy young adults. Our findings show that both the 5-HTTLPR S allele and maternal prenatal stress/child maltreatment are associated with reduced in vivo SERT mRNA expression in an additive manner. Remarkably, individuals carrying both the genetic and the environmental risk factors exhibited 32.8% (prenatal stress) and 56.3% (child maltreatment) lower SERT mRNA levels compared with those without any risk factor. Our data further indicated that changes in SERT mRNA levels were unlikely to be mediated by DNA methylation profiles within the SERT CpG island. It is thus conceivable that the persistent changes in SERT expression may in turn relate to altered serotonergic functioning and possibly convey differential disease vulnerability associated with 5-HTTLPR and early adversity.

Stratified medicine for mental disorders

There is recognition that biomedical research into the causes of mental disorders and their treatment needs to adopt new approaches to research. Novel biomedical techniques have advanced our understanding of how the brain develops and is shaped by behaviour and environment. This has led to the advent of stratified medicine, which translates advances in basic research by targeting aetiological mechanisms underlying mental disorder. The resulting increase in diagnostic precision and targeted treatments may provide a window of opportunity to address the large public health burden, and individual suffering associated with mental disorders. While mental health and mental disorders have significant representation in the "health, demographic change and wellbeing" challenge identified in Horizon 2020, the framework programme for research and innovation of the European Commission (2014-2020), and in national funding agencies, clear advice on a potential strategy for mental health research investment is needed. The development of such a strategy is supported by the EC-funded "Roadmap for Mental Health Research" (ROAMER) which will provide recommendations for a European mental health research strategy integrating the areas of biomedicine, psychology, public health well being, research integration and structuring, and stakeholder participation. Leading experts on biomedical research on mental disorders have provided an assessment of the state of the art in core psychopathological domains, including arousal and stress regulation, affect, cognition social processes, comorbidity and pharmacotherapy. They have identified major advances and promising methods and pointed out gaps to be addressed in order to achieve the promise of a stratified medicine for mental disorders.

Reflections on the interaction of psychogenic stress systems in humans: the stress coherence/compensation model

Although stress simultaneously affects and causes changes in central nervous system systems together with the sympathetic nervous system and the hypothalamus-pituitary-adrenal axis, this interaction and its behavioral consequences are rarely assessed. The current paper first describes the different systems involved in the perception and processing of stressful stimuli on an anatomical and functional level, and the available measures to assess changes in these systems. It then explores, based on theoretical and empirical grounds, the interaction of the systems. This is followed by a review of previous stress models, and how these attempted to integrate the interaction of these systems. Then, it complements previous models by suggesting a complementary regulation of the stress systems, and discusses potential behavioral consequences. Finally, based on the three-system approach to assess stress it is argued that psychological measures, together with physiological and endocrine measures are indispensable. However, the lack of consensus on how to best assess the central and sympathetic nervous system components of stress make it more difficult to include measures of all systems routinely in future stress studies. Thus, the paper closes by giving some recommendations on how to include a minimum of feasible stress measures for all systems involved in stress processing and regulation.

Prenatal adversity: a risk factor in borderline personality disorder?

BACKGROUND

Patients with borderline personality disorder (BPD) show a high prevalence of early adversity, such as childhood trauma. It has also been reported that prenatal adverse conditions, such as prenatal maternal stress, drug taking, tobacco smoking or medical complications, may be associated with an increased risk of mental disorders in the offspring. Prenatal adversity is investigated here for the first time as a potential risk factor in the diagnosis of BPD. Method A total of 100 patients with a DSM-IV diagnosis of BPD and 100 matched healthy controls underwent semi-structured interviews about the course of pregnancy, maternal stressors, birth complications and childhood trauma. Further information was obtained from the participants' mothers and from prenatal medical records.

RESULTS

Borderline patients were significantly more often exposed to adverse intrauterine conditions, such as prenatal tobacco exposure (p=0.004), medical complications (p=0.008), prenatal maternal traumatic stress (p=0.015), familial conflicts (p=0.004), low social support (p=0.004) and partnership problems during pregnancy (p=0.014). Logistic regression analyses revealed that the reported prenatal risk factors accounted for 25.7% of the variance in BPD. Prenatal tobacco exposure [odds ratio (OR) 3.37, 95% confidence interval (CI) 1.49-7.65, p=0.004] and medical complications (OR 2.87, 95% CI 1.29-6.38, p=0.010) emerged as important predictors. After controlling for childhood adversity and parental socio-economic status (SES), prenatal risk factors predicted relevant borderline subdomains, such as impulsivity, affective instability, identity disturbance, dissociation and severity of borderline symptoms.

CONCLUSIONS

This study provides evidence of an association between prenatal adversity and the diagnosis of BPD. Our findings suggest that prenatal adversity may constitute a potential risk factor in the pathogenesis of BPD.

Estudos traducionais de neuropsiquiatria e esquizofrenia: modelos animais genéticos e de neurodesenvolvimento

Sintomas psiquiátricos são subjetivos por natureza e tendem a se sobrepor entre diferentes desordens. Sendo assim, a criação de modelos de uma desordem neuropsiquiátrica encontra desafios pela falta de conhecimento dos fundamentos da fisiopatologia e diagnósticos precisos. Modelos animais são usados para testar hipóteses de etiologia e para representar a condição humana tão próximo quanto possível para aumentar nosso entendimento da doença e avaliar novos alvos para a descoberta de drogas. Nesta revisão, modelos animais genéticos e de neurodesenvolvimento de esquizofrenia são discutidos com respeito a achados comportamentais e neurofisiológicos e sua associação com a condição clínica. Somente modelos animais específicos de esquizofrenia podem, em último caso, levar a novas abordagens diagnósticas e descoberta de drogas. Argumentamos que biomarcadores moleculares são importantes para aumentar a tradução de animais a humanos, já que faltam a especificidade e a fidelidade necessárias às leituras comportamentais para avaliar sintomas psiquiátricos humanos.