Relationship between cortisol responses to stress and personality

Neuroticism and cortisol: The importance of checking for sex differences

Existent research documents an unclear and contradictory pattern between cortisol and personality variables, especially neuroticism. Specifically, no effect, positive correlations and negative correlations have all been reported to exist between cortisol and neuroticism. The current study tested whether males and females have a fundamentally different relationship between HPA activation and neuroticism and if this might partially account for some of the discrepancy in findings. Saliva samples (n=183) for cortisol were collected three times across a 90min period. Neuroticism was measured via the NEO-FFI. For men, neuroticism was positively correlated with cortisol level (r=.29). For women it was negatively correlated. The negative correlation between neuroticism and cortisol level remained when oral contraceptive use was statistically controlled, and the statistical significance actually increased (partial r=-.20). This suggests a slight suppressor effect, explainable by prior research on correlates of oral contraceptive use. Overall, these findings may offer some explanation for the discrepant results that have been reported in the existing literature regarding neuroticism and cortisol measures.

A time to be stressed? Time perspectives and cortisol dynamics among healthy adults

Perceptions of past, present, and future events may be related to stress pathophysiology. We assessed whether Time Perspective (TP) is associated with cortisol dynamics among healthy adults (N=61, Ages=18-35, M=22.9, SD=4.1) exposed to the Trier Social Stress Test (TSST). TP was measured according to two profiles: maladaptive Deviation from Balanced TP (DBTP) and adaptive Deviation from Negative TP (DNTP). Eight salivary cortisol samples were analyzed using area under the curve with respect to ground (AUCg) and to increase (AUCi). Statistic analyses involved partial correlations controlling for depressive symptoms. Results for both sexes showed that higher DBTP scores were associated with lower cortisol AUCg scores, while higher DNTP scores were associated with higher cortisol AUCg scores. These novel findings suggest that maladaptive TP profiles influence hypocortisolism, whereas adaptive TP profiles influence hypercortisolism. Thus, TP profiles may impact conditions characterized by altered cortisol concentrations.

The Cortisol Awakening Response in Patients with Poststroke Depression Is Blunted and Negatively Correlated with Depressive Mood

It is important to reduce poststroke depression (PSD) to improve the stroke outcomes and quality of life in stroke patients, but the underlying mechanisms of PSD are not completely understood. As many studies implicate dysregulation of hypothalamic-pituitary-adrenal axis in the etiology of major depression and stroke, we compared the cortisol awakening response (CAR) of 28 admitted PSD patients with that of 23 age-matched caregiver controls. Saliva samples for cortisol measurement were collected immediately, 15, 30, and 45 min after awakening for two consecutive days. Depressive mood status in PSD patients was determined with Beck Depression Inventory and Hamilton Depression Rating Scale. Salivary cortisol levels of PSD patients did not rise significantly at any sampling time, showing a somewhat flat curve. Caregiver controls showed significantly higher CAR at 15 and 30 min after awakening compared to PSD patients even though the two groups did not differ at awakening or 45 min after awakening. Area-under-the-curve analysis revealed a significant negative correlation between the CAR and the degree of depression in PSD patients. Thus, our findings suggest that poststroke depression is closely related with dysfunctional HPA axis indicated by blunted CAR.

Parental depression and child cognitive vulnerability predict children's cortisol reactivity

Risk for depression is expressed across multiple levels of analysis. For example, parental depression and cognitive vulnerability are known markers of depression risk, but no study has examined their interactive effects on children's cortisol reactivity, a likely mediator of early depression risk. We examined relations across these different levels of vulnerability using cross-sectional and longitudinal methods in two community samples of children. Children were assessed for cognitive vulnerability using self-reports (Study 1; n = 244) and tasks tapping memory and attentional bias (Study 2; n = 205), and their parents were assessed for depression history using structured clinical interviews. In both samples, children participated in standardized stress tasks and cortisol reactivity was assessed. Cross-sectionally and longitudinally, parental depression history and child cognitive vulnerability interacted to predict children's cortisol reactivity; associations between parent depression and elevated child cortisol activity were found when children also showed elevated depressotypic attributions as well as attentional and memory biases. Findings indicate that models of children's emerging depression risk may benefit from the examination of the interactive effects of multiple sources of vulnerability across levels of analysis.

Cortisol, salivary alpha-amylase and children's perceptions of their social networks

In recent years there has been a growing interest in the use of social network analysis in biobehavioral research. Despite the well-established importance of social relationships in influencing human behavior and health, little is known about how children's perception of their immediate social relationships correlates with biological parameters of stress. In this study we explore the association between two measures of children's personal social networks, perceived network size and perceived network density, with two biomarkers of stress, cortisol and salivary alpha-amylase. Forty children (mean age = 8.30, min age = 5, and max age = 12) were interviewed to collect information about their friendships and three samples of saliva were collected. Our results show that children characterized by a lower pre-interview cortisol concentration and a lower salivary alpha-amylase reactivity to the interview reported the highest density of friendships. We discuss this result in light of the multisystem approach to the study of children's behavioral outcomes, emphasizing that future work of this kind is needed in order to understand the cognitive and biological mechanisms underlying children's and adolescents' social perceptual biases.

Personality traits modulate emotional and physiological responses to stress

An individual's susceptibility to psychological and physical disorders associated with chronic stress exposure, for example, cardiovascular and infectious disease, may also be predicted by their reactivity to acute stress. One factor associated with both stress resilience and health outcomes is personality. An understanding of how personality influences responses to acute stress may shed light upon individual differences in susceptibility to chronic stress-linked disease. This study examined the relationships between personality and acute responses to stress in 125 healthy adults, using hierarchical linear regression. We assessed personality traits using the Multidimensional Personality Questionnaire (MPQ-BF), and responses to acute stress (cortisol, heart rate, blood pressure, mood) using a standardized laboratory psychosocial stress task, the Trier Social Stress Test. Individuals with high Negative Emotionality exhibited greater emotional distress and lower blood pressure responses to the Trier Social Stress Test. Individuals with high agentic Positive Emotionality exhibited prolonged heart rate responses to stress, whereas those with high communal Positive Emotionality exhibited smaller cortisol and blood pressure responses. Separate personality traits differentially predicted emotional, cardiovascular, and cortisol responses to a psychosocial stressor in healthy volunteers. Future research investigating the association of personality with chronic stress-related disease may provide further clues to the relationship between acute stress reactivity and susceptibility to disease.

Is dependent personality disorder associated with mild cognitive impairment and dementia in Central Africa? A result from the EPIDEMCA programme

BACKGROUND

To date, no studies have examined the relationship between cognitive disorders and personality disorders. Our aim was to investigate the association between dependent personality disorder (DPD) and cognitive disorders in Central Africa.

METHODS

Between 2011 and 2012, a cross-sectional multicenter population-based study was carried out in rural and urban areas of the Central African Republic (CAR) and the Republic of Congo (ROC). Participants aged ≥65 years were interviewed using the Community Screening Interview for Dementia (CSI-D). Elderly people who performed poorly (CSI-D cognitive tests score or COGSCORE ≤ 24.5/30) were clinically assessed by neurologists and underwent further psychometric testing. The Diagnostic and Statistical Manual of Mental Disorders, 4th Edition and Petersen criteria were required for the diagnosis of dementia and mild cognitive impairment (MCI) respectively. DPD was assessed using the Personality Diagnostic Questionnaire-4+. Socio-demographic, vascular, and psychological factors were also documented. Multivariate multinomial logistic regression models were used to estimate the associations.

RESULTS

Of the 2,002 participants screened, 860 and 912 had data for cognitive status and DPD in CAR and ROC respectively. In fully adjusted models, DPD was significantly associated with MCI in ROC (Odds Ratio (OR) = 2.2, 95% CI: 1.0-4.7) and CAR (OR = 2.1, 95% CI: 1.1-4.0) and with dementia only in ROC (OR = 4.8, 95% CI: 2.0-11.7).

CONCLUSIONS

DPD was associated with cognitive disorders among elderly people in Central Africa. This association should be confirmed in other contexts. This study paves the way for research on the association between personality and cognitive impairment in Africa.

Examination of cortisol and state anxiety at an academic setting with and without oral presentation

Holding oral presentations in a university course is perceived as stressful and can increase stress hormone concentrations and state anxiety. In such a naturalistic setting, further attention should be paid to the relationship between psychological and hormonal measures of acute stress, as well as women's intake of hormonal contraceptives as a potential moderating variable. In the present study, 76 healthy students gave saliva samples before and after their oral presentations in a university course as well as on a second, control day in the same course without giving an oral presentation. Anticipatory state anxiety was rated on both days. Cortisol concentrations as well as state anxiety were substantially higher on the presentation relative to the control day. During the oral presentation, an increase in cortisol concentrations was observed, whereas a decrease occurred on the control day. Nearly the same picture emerged for both variables when looking at men, women taking hormonal contraceptives and free-cycling women separately. A positive correlation was found between the change in anticipatory state anxiety in the presentation compared to the control day and cortisol concentrations before and after the oral presentation. Concluding, oral presentations constitute a potent stressor and do not seem to be substantially different between men, free-cycling women and women taking hormonal contraceptives. Future studies may want to explore changes associated with specific menstrual cycle phases and with specific hormonal contraceptives.

Revisiting shyness and sociability: a preliminary investigation of hormone-brain-behavior relations

Shyness and sociability are two fundamental personality dimensions that are conceptually and empirically orthogonal and are conserved across cultures, development, and phylogeny. However, we know relatively little regarding how shyness and sociability are represented and maintained in the brain. Here we examined neural responses to the processing of different types of social threat using event-related fMRI, the salivary cortisol awakening response (CAR), and sociability in young adults selected for high and low shyness. Shy adults who exhibited a relatively higher CAR displayed neural activity in putative brain regions involved in emotional conflict and awareness, and were more sociable. In contrast, shy adults who displayed a relatively lower CAR exhibited neural activity in putative brain regions linked to fear and withdrawal, and were unsociable. Results revealed no systematic brain responses to social threat processing that correlated with the CAR in non-shy adults. These preliminary results suggest that individual differences in waking morning cortisol levels may influence neural processes that facilitate either social approach or withdrawal among people who are shy. Findings are discussed in relation to their theoretical and clinical implications for moving beyond longstanding descriptive to explanatory models of shyness and sociability and for understanding individual differences in social behavior in general.

The Origins of Neuroticism

In this article, we provide a fresh perspective on the developmental origins of neuroticism—a dimension of temperament marked by elevated stress reactivity resulting in the frequent experience of negative emotions. This negative affectivity is accompanied by a pervasive perception that the world is a dangerous and threatening place, along with beliefs about one’s inability to manage or cope with challenging events. Historically, neuroticism has been viewed as a stable, genetically based trait. However, recent understanding of ongoing gene–environment interactions that occur throughout the life span suggests there may be a more complex and dynamic etiology. Thus, the purpose of this article is to offer a theory for understanding the development of neuroticism that integrates genetic, neurobiological, and environmental contributions to this trait. Given the strong correlation between neuroticism and the development of negative health outcomes—most notably, the full range of anxiety and mood disorders—an enhanced understanding of how neuroticism originates has implications for the treatment and prevention of a broad range of pathologies and, perhaps, even for the prevention of neuroticism itself.

Stress-induced behavioral and metabolic adaptations lead to an obesity-prone phenotype in ewes with elevated cortisol responses

The underlying cause of predisposition to obesity is complex but one marker is cortisol responsiveness. Selection of sheep for high (HR) or low (LR) cortisol responses to adrenocorticotropin shows that HR are more likely to become obese. Increased propensity to obesity is associated with reduced skeletal muscle thermogenesis. We sought to determine whether metabolic or behavioral responses to stress also contribute to altered propensity to obesity in LR and HR. Animals (n=5-10/group) were exposed to 3 stressors and we measured food intake and thermogenesis (recorded with dataloggers implanted into muscle). Stressors were hypoglycaemia (0.125 units/kg insulin, IV), a barking dog and immune challenge (200 ng/kg lipopolysaccharide--LPS, IV). LR animals showed a greater catabolic state in response to both immune and psychosocial stressors. LPS reduced (P<0.01) food intake in both groups but LR showed a greater (P<0.05) reduction in food intake and a more substantial (P<0.05) rise in muscle temperature. Introduction of the barking dog reduced (P<0.05) food intake in LR only. These metabolic differences coincided with differences in cortisol responsiveness, where HR animals had increased (P<0.05) cortisol in response to both immune and psychosocial stressors. We also assessed behavior in the following paradigms: 1, isolation in the open field test; 2, response to a human intruder; and 3, food competition. LR had greater (P<0.05) activity, reduced fearfulness and displayed a proactive coping style of behavior. Thus we demonstrate that high cortisol responsiveness identifies animals with stress-induced metabolic and behavioral traits that may contribute to susceptibility to obesity.

Association between corticotropin-releasing hormone receptor 1 and 2 (CRHR1 and CRHR2) gene polymorphisms and personality traits

Previous studies have reported that the hypothalamic-pituitary-adrenal axis is involved with personality traits. We examined the association between corticotropin-releasing hormone receptor (CRHR) genes and personality traits. We investigated the 12 single-nucleotide polymorphisms of intron CRHR (six in CRHR1 and six in CRHR2, respectively) in 218 healthy volunteers using TaqMan PCR assays. Personality traits were assessed using the Revised NEO-Personality Inventory, the Temperament and Character Inventory, and the State-Trait Anxiety Inventory. No significant associations were observed between CRHR1 and CRHR2 expression and personality traits. These results fail to provide support for an association of CRHR1 and CRHR2 with personality traits in a Japanese adult population.

Adolescent personality: associations with Basal, awakening, and stress-induced cortisol responses

The purpose of the present study was to investigate the associations between personality facets and hypothalamic-pituitary-adrenal (HPA) axis functioning. Previous studies have mainly focussed on stress-induced HPA-axis activation. We hypothesized that other characteristics of HPA-axis functioning would have a stronger association with personality based on the neuroendocrine literature. Data (n = 343) were used from the TRacking Adolescents' Individual Lives Survey (TRAILS), a large prospective cohort study of Dutch adolescents. We studied the association between facets of Neuroticism, Extraversion, and Conscientiousness and basal cortisol, the cortisol awakening response (CAR), and four measures of stress-induced HPA-axis activity. Basal cortisol levels were related to facets of all three personality traits. The CAR and stress-induced cortisol were not related to personality. Possibly due to its more trait-like nature, basal cortisol seems more informative than stress-induced cortisol when investigating trait-like characteristics such as personality facets.

Impulsivity, risk taking, and cortisol reactivity as a function of psychosocial stress and personality in adolescents

Although adolescence is characterized by hormonal changes and increased disinhibited behaviors, explanations for these developmental changes that include personality and environmental factors have not been fully elucidated. We examined the interactions between psychosocial stress and the traits of negative emotionality and constraint on impulsive and risk-taking behaviors as well as salivary cortisol reactivity in 88 adolescents. In terms of behavioral outcomes, analyses revealed that negative emotionality and constraint were protective of impulsivity and risk taking, respectively, for adolescents in the no-stress condition; personality did not relate to either behavior in the stress condition. Low-constraint adolescents in the stress condition engaged in less risk taking than low-constraint adolescents in the no-stress condition, whereas there was no effect of stress group for high-constraint adolescents. In terms of cortisol reactivity, analyses revealed that low-constraint adolescents in the stress condition exhibited greater cortisol reactivity compared to high-constraint adolescents, which suggests that low-constraint adolescents mobilize greater resources (e.g., increased cognitive control, heightened attention to threat) in stressful situations relative to nonstressful ones. These results demonstrate that two facets of disinhibition and cortisol reactivity are differentially affected by psychosocial stress and personality (and their interactions) in adolescents.

The Brain Derived Neurotrophic Factor and Personality

The study of the biological basis of personality is a timely research endeavor, with the aim of deepening our understanding of human nature. In recent years, a growing body of research has investigated the role of the brain derived neurotrophic factor (BDNF) in the context of individual differences across human beings, with a focus on personality traits. A large number of different approaches have been chosen to illuminate the role of BDNF for personality, ranging from the measurement of BDNF in the serum/plasma to molecular genetics to (genetic) brain imaging. The present review provides the reader with an overview of the current state of affairs in the context of BDNF and personality.

Job stress and agentic-communal personality traits related to serum cortisol levels of male workers in a Japanese medium-sized company: a cross-sectional study

BACKGROUND

Although serum cortisol is a widely accepted index of stress levels, associations between job stress and cortisol levels have been inconsistent. Individual differences in personality traits were discussed as one compelling explanation for this discrepancy. Agentic-communal personality traits have been examined as possible predictive factors for psychological stress.

PURPOSE

This study investigated correlations among agentic-communal personality traits and serum cortisol levels. It was also investigated whether job stress levels modified correlations between agentic-communal personality and cortisol levels.

METHODS

Participants were 198 male workers (mean age = 52.2 years) employed by a shipbuilding company in Japan. Questionnaire data and blood samples were collected during an annual health checkup. Participants completed a self-report questionnaire that included the Job Content Questionnaire (JCQ) that assesses job control as job stress levels the Communion-Agency scale (CAS) and questions regarding health behaviors.

RESULTS

Communion positively correlated with serum cortisol levels and unmitigated agency negatively correlated with serum cortisol levels. Stratified by job control, communion positively correlated with serum cortisol levels and agency negatively correlated with serum cortisol levels in participants with low levels of job control. Unmitigated agency negatively correlated with serum cortisol levels in participants with high levels of job control.

CONCLUSION

Levels of job control may modify correlations of gender-related personality with serum cortisol levels. Especially with exposure to high job stress, male workers with high femininity (i.e., high communion and low agency) were more likely to have a high stress response as measured by serum cortisol levels.

The relationship between recent stressful life events, personality traits, perceived family functioning and internet addiction among college students

Internet addiction (IA) is an emerging social and mental health issue among youths. Analysis of risk factors, as well as their interactions, is crucial for understanding the development of IA. This study investigated the relationship between recent stressful life events, personality traits, perceived family functioning and IA in 892 college students. Subjects were classified into categories (non-addicted, mild IA or severe IA) using the Chen Internet Addiction Scale. Stressful life events, personality traits and family functioning were assessed using the Adolescent Self-Rating Life Events Checklist, the Eysenck Personality Questionnaire, and the Family Adaptability and Cohesion Scale, respectively. The results indicated that compared with non-addicted subjects, subjects with severe IA (9.98%) had lower family functioning, lower extraversion, higher neuroticism and psychoticism, and more stressful life events, and subjects with mild IA (11.21%) had higher neuroticism and more health and adaptation problems. Neuroticism and health and adaptation problems were potential predictors of IA. An interaction effect between psychoticism and total life stress on IA was also found. These findings highlight the role of personality traits and life stress and their interactions in college students' IA. Further research should explore the mechanisms underlying the interaction effect of psychoticism with life stress on IA.

The role of openness to experience and sexual identity formation in LGB individuals: implications for mental health

Openness to experience has been shown to have a positive impact on mental health in the general population, but there is a dearth of information both about why this is the case and on LGB populations in this area. The present article explores the relationship between openness to experience, LGB identity development, and mental health. The results revealed a full mediation model, where the positive impact of openness to experience on mental health is fully mediated by positive LGB identity development. Limitations and implications are discussed.

Biological and psychological markers of stress in humans: focus on the Trier Social Stress Test

Validated biological and psychological markers of acute stress in humans are an important tool in translational research. The Trier Social Stress Test (TSST), involving public interview and mental arithmetic performance, is among the most popular methods of inducing acute stress in experimental settings, and reliably increases hypothalamic-pituitary-adrenal axis activation. However, although much research has focused on HPA axis activity, the TSST also affects the sympathetic-adrenal-medullary system, the immune system, cardiovascular outputs, gastric function and cognition. We critically assess the utility of different biological and psychological markers, with guidance for future research, and discuss factors which can moderate TSST effects. We outline the effects of the TSST in stress-related disorders, and if these responses can be abrogated by pharmacological and psychological treatments. Modified TSST protocols are discussed, and the TSST is compared to alternative methods of inducing acute stress. Our analysis suggests that multiple readouts are necessary to derive maximum information; this strategy will enhance our understanding of the psychobiology of stress and provide the means to assess novel therapeutic agents.

Race differences in the relation of vitamins A, C, E, and β-carotene to metabolic and inflammatory biomarkers

Using archival data, we conducted a secondary analysis to examine race differences in the relation of serum vitamins A, C, E and β-carotene to insulin resistance (IR), fasting insulin and glucose, high sensitivity C-reactive protein (hs-CRP), and leukocyte count in 176 non-smoking, healthy, white, and African American (AA) adults aged 18 to 65 years (48% women, 33% AA). We hypothesized that micronutrient concentrations would be associated with early risk markers of cardiometabolic diseases in a race-dependent manner. Fasting blood samples were analyzed for micronutrients, insulin, glucose, hs-CRP, and leukocyte count. Insulin resistance was estimated using the homeostatic model assessment. After adjusting for age, body mass index, gender, educational level, use of vitamin supplements, alcohol intake, leisure time physical activity, menopausal status, and total cholesterol, we observed that β-carotene was significantly associated with insulin resistance and fasting insulin in a race-dependent manner. Among AA, lower β-carotene levels were associated with higher estimates of insulin resistance and fasting insulin; whereas, these same associations were not significant for whites. Race also significantly moderated the relation of vitamin C to leukocyte count, with lower vitamin C being associated with higher leukocyte count only in AA but not whites. For all subjects, lower β-carotene was associated with higher hs-CRP. In AA, but not whites, lower levels of β-carotene and vitamin C were significantly associated with early risk markers implicated in cardiometabolic conditions and cancer. Whether or not lower levels of micronutrients contribute uniquely to racial health disparities is a worthwhile aim for future research.

Variation in the stress response between high- and low-neuroticism female undergraduates across the menstrual cycle

This study was undertaken to elucidate possible relationships between menstrual cycle stage, neuroticism and behavioral and physiological responses to a cognitive challenge. The study investigated the differences between high neuroticism and low neuroticism groups across the menstrual cycle (luteal, menstrual and ovulatory stages). The Stroop color-naming task was used as a stressor. During the task, the galvanic skin response (GSR), heart rate (HR) and HR variability (HRV) were simultaneously recorded by a polygraph. The results showed a significant difference in reaction times (RT) on the Stroop task between the high- and low-neuroticism groups during menstruation. However, there were no significant RT differences between groups during the luteal or ovulatory cycle stages. The GSR of the high-neuroticism group during menstruation was significantly lower than it was in the luteal and ovulatory stages. Moreover, during menstruation, the cardiovascular responses (high-frequency HRV (HF) and low-frequency HRV (LF)) and accuracy on the Stroop task were positively correlated, while the correlations between HF, LF and the RT were negative. The results demonstrate that during menstruation, there were consistent variations in female behavior and physiology when facing a cognitive stressor. Specifically, the high-neuroticism group was more sensitive to the stressor than the low neuroticism group, with decreased reaction time on the Stroop task, and increased GSR and HRV.

Individual differences in mate poaching: an examination of hormonal, dispositional, and behavioral mate-value traits

The personality and hormonal correlates of mate poaching (attempting to steal another person's partner away) and of the target of the seducer (the mate poached) were examined in a sample 154 undergraduate university students (91 females; 63 males). Thirteen variables were modeled into two regression equations to predict and profile mate poachers and the mate poached. Findings revealed that (1) male mate poachers were better looking and had higher cortisol levels, lower levels of testosterone, and reported being higher on self-esteem, cold affect, and criminal tendencies and (2) female mate poachers and targets of mate poachers reported being more physically attractive, as did male targets of mate poachers. Sex differences in the context of mate poaching attraction as well as the characteristics of those who are successful in their attempts to lure away another person's romantic partner were discussed.

Possible rheumatoid arthritis subtypes in terms of rheumatoid factor, depression, diagnostic delay and emotional expression: an exploratory case-control study

Introduction

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis has been implicated in the pathology of rheumatoid arthritis (RA), particularly as vulnerable personality types are exposed to chronic stress. Emotions are powerful modulators of stress responses. However, little is known about whether patients with RA process emotions differently to matched controls. In this study we: 1) assessed whether the trait emotional intelligence (trait EI) scores of patients with RA differ from healthy controls at the facet level; 2) explored any subgroups in RA, in terms of trait EI and common risk factors.

Methods

A total of 637 patients with RA were compared to 496 controls on the trait EI Questionnaire (TEIQue). RA subgroups were explored in terms of trait EI, rheumatoid factor status (RF+/-), depression and time from onset of symptoms until diagnosis (diagnostic delay).

Results

The RA group rated themselves lower on Adaptability, Stress-management, Emotion management, Self-esteem, Sociability, Assertiveness, Impulsiveness and Well-being, and higher on Empathy and Relationships than healthy controls. The RF- subtype reported more time with depression (25.2 vs. 11.3 months), a longer diagnostic delay (3.0 vs. 1.7 years), and greater emotional expression (5.15 vs. 4.72), than the RF+ subtype. These differences were significant at the P <0.05 level, but not following strict Bonferroni corrections and should therefore be treated as indicative only. RF- patients with a longer diagnostic delay reported depression lasting three times longer (42.7 months), when compared to three other subtypes (11.0 to 12.7 months).

Conclusions

RA patients and controls differ in their emotion-related personality traits, as operationalized by trait EI. These differences may make people with RA more susceptible to chronic stress and HPA-axis dysregulation. RA may be a highly heterogeneous illness where at least two subtypes may be characterized by personality, psychiatric and immunological differences. RF- status, as well as diagnostic delay and emotional expression, may predict future risk of depression. Research on the causes of RA could benefit from a systems science approach.

Psychoendocrine and psychoneuroimmunological mechanisms in the comorbidity of atopic eczema and attention deficit/hyperactivity disorder

Epidemiological data indicate that atopic eczema (AE) in infancy significantly increases the risk for attention deficit/hyperactivity disorder (ADHD) in later life. The underlying pathophysiological mechanisms of this comorbidity are unknown. We propose that the release of inflammatory cytokines caused by the allergic inflammation and/or elevated levels of psychological stress as a result of the chronic disease interfere with the maturation of prefrontal cortex regions and neurotransmitter systems involved ADHD pathology. Alternatively, increased stress levels in ADHD patients may trigger AE via neuroimmunological mechanisms. In a third model, AE and ADHD may be viewed as two separate disorders with one or more shared risk factors (e.g., genetics, prenatal stress) that increase the susceptibility for both disorders leading to the co-occurrence of AE and ADHD. Future investigation of these three models may lead to a better understanding of the mechanisms underlying the observed comorbidity between AE and ADHD and further, to targeted interdisciplinary primary prevention and treatment strategies.

Gender effect on the relationship between stress hormones and panic-agoraphobic spectrum dimensions in healthy subjects

INTRODUCTION

Alterations of the hypothalamic-pituitary-adrenal (HPA) axis and of its peripheral indices have been reported in both normal and pathological anxiety with controversial findings. The aim of the present study was to investigate the possible correlations between serum cortisol and dehydroepiandrosterone-sulfate (DHEA-S) levels and DHEA-S/cortisol ratio, and panic-agoraphobic spectrum dimensions in a sample of healthy subjects.

METHODS

Forty-two healthy subjects of both sexes, with no current or lifetime psychiatric disorders, were assessed by means of the Structured Clinical Interview for DSM-IV (SCID-I/P) and the so-called Panic Agoraphobic Spectrum-Self Report lifetime version (PAS-SR).

RESULTS

Significant, negative correlations were found between cortisol levels and the total score of the separation sensitivity, panic-like symptoms, and medication/substance sensitivity PAS-SR domains. The PAS-SR total and the panic-like symptoms domain scores were positively related to the DHEAS/cortisol ratio. When the sample was divided in women and men, these correlations were present in women only.

DISCUSSION

These findings, while indicating the presence of significant relationships between panic-agoraphobic traits and some indices of HPA axis functioning in healthy women, would suggest this as one of the factors explaining the greater vulnerability of women to cross the line between normal and pathological anxiety.

CONCLUSIONS

Further studies are needed to explore gender differences in the relationships between HPA axis alterations and the panic-agoraphobic spectrum dimensions.

Personality and physiological reactions to acute psychological stress

Stable personality traits have long been presumed to have biological substrates, although the evidence relating personality to biological stress reactivity is inconclusive. The present study examined, in a large middle aged cohort (N=352), the relationship between key personality traits and both cortisol and cardiovascular reactions to acute psychological stress. Salivary cortisol and cardiovascular activity were measured at rest and in response to a psychological stress protocol comprising 5min each of a Stroop task, mirror tracing, and a speech task. Participants subsequently completed the Big Five Inventory to assess neuroticism, agreeableness, openness to experience, extraversion, and conscientiousness. Those with higher neuroticism scores exhibited smaller cortisol and cardiovascular stress reactions, whereas participants who were less agreeable and less open had smaller cortisol and cardiac reactions to stress. These associations remained statistically significant following adjustment for a range of potential confounding variables. Thus, a negative personality disposition would appear to be linked to diminished stress reactivity. These findings further support a growing body of evidence which suggests that blunted stress reactivity may be maladaptive.

Trait anxiety and post-learning stress do not affect perceptual learning

While it is well established that stress can modulate declarative learning, very few studies have investigated the influence of stress on non-declarative learning. Here, we studied the influence of post-learning stress, which effectively modulates declarative learning, on perceptual learning of a visual texture discrimination task (TDT). On day one, participants trained for one session with TDT and were instructed that they, at any time, could be exposed to either a high stressor (ice-water; Cold Pressor Test; CPT) or a low stressor (warm water). Participants did not know when or which stressor they would be exposed to. To determine the impact of the stressor on TDT learning, all participants returned the following day to perform another TDT session. Only participants exposed to the high stressor had significantly elevated cortisol levels. However, there was no difference in TDT improvements from day one to day two between the groups. Recent studies suggested that trait anxiety modulates visual perception under anticipation of stressful events. Here, trait anxiety did neither modulate performance nor influence responsiveness to stress. These results do not support a modulatory role for stress on non-declarative perceptual learning.

Biological sex and menstrual cycle phase modulation of cortisol levels and psychiatric symptoms in a non-clinical sample of young adults

Prior research examined the complex, bidirectional interplay of the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal axes and their roles in (clinical) cognitive/behavioral functions. Less well understood are contemporaneous relationships in non-clinical samples. This pilot study explored cortisol in relation to psychiatric symptoms/personality as a function of self-reported menstrual cycle phase and sex differences in a non-clinical, young adult sample. Consistent with literature and hypotheses, cortisol levels were lowest during early-follicular, intermediary during late-follicular, and highest during mid-luteal phases (not significant), and greater among males than early-follicular females. An acute stressor uniformly affected cortisol across phases and sex, though magnitude and time course differed. Psychiatric symptoms were greater among early-follicular/late-follicular females versus males, and early-follicular and/or late-follicular versus mid-luteal. Contrary to hypotheses, positive psychotic-like symptoms were greater among males than (mid-luteal) females. Cortisol inversely related to early-follicular symptoms, and directly related to late-follicular/mid-luteal symptoms. Results suggest menstrual cycle phase modulates non-clinical psychiatric symptomatology and HPA activity. Findings tentatively bolster a dimensional/continuum model of psychopathology with implications for understanding neurobiological underpinnings and risk/protective factors for mental/physical health conditions, particularly those marked by sex differences and neuroendocrine dysfunction (depression/schizophrenia/Alzheimer's/multiple sclerosis). We speculate a dose-response cortisol effect on symptoms, modulated by endogenous gonadal hormones via gene expression.

Premorbid personality traits and their course in mild cognitive impairment: results from a prospective population-based study in Germany

BACKGROUND

Personality traits contribute to cognitive functioning. We present a study comparing personality traits in normal ageing and mild cognitive impairment (MCI).

METHODS

We conducted a representative longitudinal study including 222 subjects from a cohort born between 1930 and 1932 (n = 500) examined at three examination waves (t1: 1993/1994; t2: 1997/1998; t3: 2005/2007). Personality traits were assessed with the NEO-Five-Factor Inventory questionnaire.

RESULTS

Healthy controls and patients with MCI showed a significant (p < 0.05) decrease concerning their levels of neuroticism and extraversion over time. MCI subjects scored significantly higher on neuroticism at baseline and lower on openness at all examinations compared to healthy controls. Subjects with higher baseline neuroticism showed a 2.24 times higher risk of developing MCI at the third follow-up (odds ratio = 2.24, 95% confidence interval = 1.12-4.45 - scores adjusted for education and sex).

CONCLUSIONS

MCI subjects differ in their premorbid personality traits compared to healthy controls. According to our study, higher neuroticism should be considered a risk factor for the development of MCI.

The influence of neuroticism, extraversion and openness on stress responses

The present research moved beyond focusing on negative dispositions to investigate the influence of positive aspects of personality, namely extraversion and openness, on stress responses including appraisals, affect and task performance. Challenge appraisals occur when stressor demands are deemed commensurate with coping resources, whereas threat appraisals occur when demands are believed to outweigh coping resources. We examined the unique influence of personality on stress responses and the mediating role of appraisals. Personality was assessed, and then participants (N = 152) were exposed to a validated math stressor. We found unique effects on stress responses for neuroticism (high threat and negative affect and low positive affect), extraversion (high positive and low negative affect) and openness (high positive and low negative effect and better performance). Mediation analyses revealed that neuroticism indirectly worsened performance, through threat appraisals, and that openness indirectly increased positive affect through lower threat. These findings highlight the importance of investigating multiple aspects of personality on stress responses and provide an avenue through which stress responses can be changed-appraisals. Only by more broad investigations can interventions be tailored appropriately for different individuals to foster stress resilience.

The influence of gene-environment interactions on the development of alcoholism and drug dependence

Alcoholism and drug dependence are common psychiatric disorders with a heritability of about 50%; therefore genetic and environmental influences are equally important. Early-life stress is a predictor of adolescent problem drinking/drug use and alcohol/drug dependence in adulthood, but moderating factors governing the availability of alcohol/drug are important. The risk-resilience balance for addiction may be due in part to the interaction between genetic variation and environment stressors (G × E); this has been confirmed by twin studies of inferred genetic risk. Measured genotype studies to detect G × E effects have used a range of alcohol consumption and diagnostic phenotypes and stressors ranging from early-life to adulthood past year life events. In this article, the current state of the field is critically reviewed and suggestions are put forth for future research.

Openness to experience and mortality in men: analysis of trait and facets

OBJECTIVES

We examined whether specific facets are more robust predictors of mortality risk than overall trait openness in a sample of older men.

METHODS

The current investigation used data from 1,349 men from the Veterans Affairs Normative Aging Study. From 1990-1991 to 2008, 547 (41%) had died. We used exploratory factor analysis to extract facets of openness, followed by proportional hazards modeling to examine 18-year mortality risk.

RESULTS

Two facets emerged from the openness adjectives: intellect and creativity. In the fully adjusted model, only creativity predicted mortality risk. A 1-SD increase in creativity was associated with a 12% decrease in mortality risk.

DISCUSSION

The study demonstrated that consideration of facets allows for a more precise understanding of the personality-health association. Higher levels of creativity predict longer survival in a sample of older men which provides preliminary support of the protective role creativity has on health even at advanced ages.

The Trier Social Stress Test protocol for inducing psychological stress

This article demonstrates a psychological stress protocol for use in a laboratory setting. Protocols that allow researchers to study the biological pathways of the stress response in health and disease are fundamental to the progress of research in stress and anxiety. Although numerous protocols exist for inducing stress response in the laboratory, many neglect to provide a naturalistic context or to incorporate aspects of social and psychological stress. Of psychological stress protocols, meta-analysis suggests that the Trier Social Stress Test (TSST) is the most useful and appropriate standardized protocol for studies of stress hormone reactivity. In the original description of the TSST, researchers sought to design and evaluate a procedure capable of inducing a reliable stress response in the majority of healthy volunteers. These researchers found elevations in heart rate, blood pressure and several endocrine stress markers in response to the TSST (a psychological stressor) compared to a saline injection (a physical stressor). Although the TSST has been modified to meet the needs of various research groups, it generally consists of a waiting period upon arrival, anticipatory speech preparation, speech performance, and verbal arithmetic performance periods, followed by one or more recovery periods. The TSST requires participants to prepare and deliver a speech, and verbally respond to a challenging arithmetic problem in the presence of a socially evaluative audience. Social evaluation and uncontrollability have been identified as key components of stress induction by the TSST. In use for over a decade, the goal of the TSST is to systematically induce a stress response in order to measure differences in reactivity, anxiety and activation of the hypothalamic-pituitary-adrenal (HPA) or sympathetic-adrenal-medullary (SAM) axis during the task. Researchers generally assess changes in self-reported anxiety, physiological measures (e.g. heart rate), and/or neuroendocrine indices (e.g. the stress hormone cortisol) in response to the TSST. Many investigators have adopted salivary sampling for stress markers such as cortisol and alpha-amylase (a marker of autonomic nervous system activation) as an alternative to blood sampling to reduce the confounding stress of blood-collection techniques. In addition to changes experienced by an individual completing the TSST, researchers can compare changes between different treatment groups (e.g. clinical versus healthy control samples) or the effectiveness of stress-reducing interventions.

Effects of panel sex composition on the physiological stress responses to psychosocial stress in healthy young men and women

Men and women differ in regard to psychosocial stress responses. Biological and contextual factors are known to mediate these differences; however, few studies investigated their interaction. In the present study, we examined contributions of both contextual and biological factors to the stress response of young healthy adults. Men and women were exposed to a modified version of Trier Social Stress Test. The participants gave a speech in front of a panel of judges, composed of either male or female panelists. Both men, and women presented a cortisol increase only when exposed to opposite sex panelists. Interestingly, this effect was only observed in women in their follicular phase. This finding showed that the induction of a psychosocial stress response does not strictly rely on direct social evaluation, but also depends on the sex composition of the panel. Implications for future studies are discussed.

Psychoticism and neuroticism predict cocaine dependence and future cocaine use via different mechanisms

BACKGROUND

Personality characteristics have been associated with cocaine use. However, little is known about the mechanisms through which personality could impact drug use. The present study investigated the cross-sectional and prospective relationships between personality dimensions (i.e., impulsivity, neuroticism) and problematic cocaine use. Reactivity to a pharmacological stressor as a potential mediator of the relationship between neuroticism and future cocaine use was also examined.

METHODS

Participants were 53 cocaine-dependent individuals and 47 non-dependent controls. Subjects completed the Eysenck Personality Questionnaire (EPQ) at baseline and were administered i.v. corticotrophin releasing hormone (CRH; 1 μg/kg). Cocaine use in the 30 days following CRH administration was measured.

RESULTS

Cocaine-dependent individuals had higher scores on the psychoticism (i.e., impulsivity, aggression; p=0.02) and neuroticism (p<0.01) scales of the EPQ than non-dependent controls. Cocaine-dependent individuals also had a greater subjective stress response to CRH than controls (p<0.01). Cocaine-dependent individuals with elevated psychoticism used significantly more cocaine over the follow-up period (p<0.05), whereas individuals with elevated neuroticism trended towards using cocaine more frequently over the follow-up (p=0.07). Finally, there was a trend for an indirect effect of neuroticism on frequency of cocaine use through subjective reactivity to CRH.

CONCLUSIONS

The findings extend past research on the association between personality and cocaine use, and suggest that motives for cocaine use may systematically vary across personality characteristics. Moreover, tailoring therapeutic interventions to individuals' personalities may be an area that warrants further investigation.

Effects of acute psychosocial stress exposure on endocrine and affective reactivity in college students differing in the 5-HTTLPR genotype and trait neuroticism

Enhanced stress vulnerability has been implicated in the pathogenesis of affective disorders. Although both genetic (5-HTTLPR) and cognitive (neuroticism) factors are known to increase stress vulnerability, no experimental study has investigated the interaction between these two factors on psychobiological reactivity following acute stress exposure. This study used a balanced experimental design to examine the interaction between the 5-HTTLPR genotype and trait neuroticism in neuroendocrine and affective stress responses. From a large group of 771 students, 48 carriers of the short/short (S/S) allele and 48 carriers of the long/long (L/L) allele with the lowest and the highest neuroticism scores (77 females, 19 males; mean age ± SD: 20.6 ± 2 years) were selected and exposed to an acute psychosocial stressor. Mood was assessed before and after the stressor, and salivary cortisol concentrations were measured before and at 20, 30, and 60 min after stressor onset. Acute stress increased salivary cortisol concentration regardless of either 5-HTTLPR genotype or neuroticism, but it caused a less profound negative mood change in L/L compared to S/S-allele carriers with the lowest neuroticism scores. The 5-HTTLPR genotype influences affective reactivity to acute stress conditional upon neuroticism, improving resilience to acute stress in L/L-allele carriers if they do not already possess high cognitive-affective (neuroticism) vulnerability.

Negative emotionality, depressive symptoms and cortisol diurnal rhythms: analysis of a community sample of middle-aged males

Prior research suggests that individuals with particular personality traits, like negative emotionality, are at greater risk for adverse health outcomes. Despite bivariate associations between negative emotionality, depressive symptoms and the hypothalamic pituitary adrenal axis (HPA axis), few studies have sought to understand the biological pathways through which negative emotionality, depressive symptomatology and cortisol-one of the primary hormonal products of the HPA axis--are associated. The present study explored whether negative emotionality influenced cortisol dysregulation through current depressive symptomatology and whether negative emotionality served as a moderator of the relationship between depressive symptoms and cortisol. In the community-based Vietnam Era Twin Study of Aging, 783 male twins completed two days of cortisol saliva sampling in their natural environments. Three measures of cortisol were analyzed: waking levels, the cortisol awakening response, and the peak to bed slope. Depressive symptoms significantly mediated the associations between negative emotionality and the peak to bed slope. A 2-way interaction between depressive symptoms and negative emotionality was significant for the peak to bed slope and for waking levels of cortisol. Exploration of the interactions illustrated that depressive symptoms only affected cortisol slopes at average or high levels of negative emotionality and only affected waking levels at low levels of negative emotionality. Negative emotionality and depressive symptoms were not related to the cortisol awakening response. This is the first study to find indirect associations between negative emotionality and peak to bed cortisol slopes through depressive symptoms. These findings illustrate the complex interplay between personality characteristics, depressive symptoms and different indices of the cortisol diurnal rhythm.

Sex-specific cortisol levels in bipolar disorder and schizophrenia during mental challenge--relationship to clinical characteristics and medication

OBJECTIVE

Our objective was to examine the cortisol release during a mental challenge in severe mental disorders versus healthy controls (HC), analyzing effects of sex, clinical characteristics and medication, and comparing Bipolar Disorder (BD) to Schizophrenia (SCZ).

METHODS

Patients with BD and SCZ (n=151) were recruited from a catchment area. HC (n=98) were randomly selected from the same area. Salivary samples were collected before and after a mental challenge and cortisol levels determined.

RESULTS

During the challenge there was an interaction between group and sex (P = 0.015) with male patients having a blunted cortisol release compared to male HC (P = 0.037). Cortisol change did not differ significantly between BD and SCZ. In all patients, the cortisol change correlated with number of psychotic episodes (r = -0.23, P = 0.025), and in females patients, with number of depressive episodes (r = -0.33, P = 0.015). Patients using antidepressants had a greater cortisol release during challenge than those not using antidepressants (P = 0.043).

CONCLUSIONS

Male patients with severe mental disorders seem to have a uniform abnormal cortisol release during mental challenges which associates with clinical course, and with beneficial effects of antidepressants.

The role of early life stress as a predictor for alcohol and drug dependence

RATIONALE

Genetic and environmental influences on the development of alcohol and drug dependence are equally important. Exposure to early life stress, that is unfortunately common in the general population, has been shown to predict a wide range of psychopathology, including addiction.

OBJECTIVE

This review will look at the characteristics of early life stress that may be specific predictors for adolescent and adult alcohol and drug dependence and will focus on studies in humans, non-human primates and rodents.

RESULTS

Experiencing maltreatment and cumulative stressful life events prior to puberty and particularly in the first few years of life is associated with early onset of problem drinking in adolescence and alcohol and drug dependence in early adulthood. Early life stress can result in permanent neurohormonal and hypothalamic-pituitary-adrenal axis changes, morphological changes in the brain, and gene expression changes in the mesolimbic dopamine reward pathway, all of which are implicated in the development of addiction. However, a large proportion of children who have experienced even severe early life stress do not develop psychopathology indicating that mediating factors such as gene-environment interactions and family and peer relationships are important for resilience.

CONCLUSIONS

There appears to be a direct pathway from chronic stress exposure in pre-pubertal children via adolescent problem drinking to alcohol and drug dependence in early adulthood. However, this route can be moderated by genetic and environmental factors. The role that gene-environment interactions play in the risk-resilience balance is being increasingly recognized.

Psychological health throughout life and adult cortisol patterns at age 45 y

Population-based studies of cortisol and psychological health over long periods are rare. This study aims to establish whether cortisol levels in mid-adulthood are associated with chronicity and life-stage of psychological ill-health onset. We used data from the 1958 British birth cohort (3209 males; 3315 females) with cortisol measures 45 min post-waking (t1) and 3h later (t2) on the same day at 45y. Lifetime psychological health was identified from child and adult measures (ages 7, 11, 16, 23, 33, 42, 45y). t1 cortisol was lower by 3-4% in those with lifetime (child and adult) ill-health than those with no ill-health, after adjustment for socio-economic position and smoking. t1 cortisol was similarly lowered in those with adult onset of ill-health, but not among the group whose ill-health was of recent onset. t2 cortisol was elevated among all lifetime ill-health groups, by 6-9%, except for those whose ill-health did not extend beyond childhood. Simple analyses across the separate ages of follow-up suggest that elevations in t2 cortisol reflect associations for adult ill-health. Our study suggests that psychological ill-health over years and decades "blunts" post-awakening cortisol secretion, possibly reflecting HPA dysregulation due to social stressors.

The cortisol awakening response in patients remitted from depression

An impressive number of data has been accumulated on dysfunctions of the hypothalamo-pituitary-adrenal (HPA) axis and cortisol hypersecretion in depression. To assess the dynamic HPA functioning, the cortisol awakening response (CAR) is an easily accessible and reliable approach. Some data suggest that elevated CAR in depressed patients has trait-like characteristics. Therefore we investigated whether patients in remission from a depressive episode have elevated CAR compared to control subjects. CAR of thirty-eight patients in remission from depression (11 men, 27 women, age range 24-66) and 52 control participants were analyzed (18 men, 34 women, age range 24-63). All patients had experienced ≥3 previous depressive episodes and were off psychotropic medication since at least 3 months. Saliva samples were collected only once, at home, either on weekend or weekday at 0, 15, 30, 45 and 60 min post-awakening. The area under the curve (AUC) above minimum cortisol concentration displayed large interindividual variability (6.4-fold in remitted patients and 8.1-fold in controls, based on 80% range). Investigation of possible variability factors showed that percent explained variance increased from 3.9% when group was considered alone to 8.8%, 12.3% and 19.2% after adjusting for significant effects of weekday vs. weekend, wake-up time and sleep duration, respectively. According to the latter model, AUC was estimated to be 51% higher in remitted patients than in controls (p = 0.007), while a 21% AUC decrease was associated with a 1-h longer sleep duration (p<0.001). In future studies, detection of between-group differences might benefit from adjusting for sleep duration and other possible confounders.