Symptom-specific associations between low cortisol responses and functional somatic symptoms: the TRAILS study

Hair cortisol and self-perceived stress in adolescents with multi-system functional somatic disorders

BACKGROUND

Long-term stress causing altered hypothalamic-pituitary-adrenal (HPA) axis dynamics with cortisol dysfunction may be involved in the pathophysiology of functional somatic disorders (FSD), but studies on adolescents with multi-system FSD are lacking. Therefore, we investigated: 1) whether hair cortisol concentration (HCC) differentiates adolescents with multi-system FSD from a) a population-based sample and b) a subgroup derived from the sample reporting a high physical symptom load, and 2) whether FSD population HCC is associated with primary symptom presentations and self-perceived stress.

METHODS

We used data from a clinical sample with multi-system FSD (N = 91, age 15-19 years) and a population-based sample (N = 1,450, age 16-17 years) including a subgroup with top 10% total scores on physical symptoms (N = 147). Density plots and multiple linear regression were applied to compare HCC between groups. In the clinical sample, multiple linear regression was employed to assess the association between HCC and primary symptom clusters and self-perceived stress.

RESULTS

Median HCC was lower in the clinical sample than in the population-based sample (β = 0.80 (95%CI: 0.66, 0.97)), but not significantly different from median HCC in the derived subgroup (β = 0.84 (95%CI: 0.66, 1.07)). In the clinical sample, HCC was not significantly associated with primary symptom clusters (F(2, 82) = 0.13, p = 0.88) or self-perceived stress (F(4, 83) = 1.18, p = 0.33).

CONCLUSION

Our findings indicate that HCC is lowered in adolescents with multi-system FSD but not significantly associated with primary symptom presentations or self-perceived stress. Future studies including multiple measures of HPA axis dynamics alongside psychological measures may further elucidate the role of long-term stress in FSD.

TRIAL REGISTRATION

The AHEAD study was pre-registered at ClinicalTrials.gov (NCT02346071), 26/01/2015.

The association between parental chronic physical illness and adolescent functional somatic symptoms

BACKGROUND

Previous studies have found that adolescents with a chronically ill parent may experience more internalizing problems. It is less clear if this association is sex-related, and whether it is specific for functional somatic symptoms (FSSs) or concerns other internalizing or externalizing problems.

METHODS

In a prospective cohort of adolescents, oversampled on emotional and behavioral problems (n = 841; mean age 14.9 years), we examined the association between parental chronic illness and adolescent's FSSs, and internalizing and externalizing problems. Adolescent's internalizing and externalizing symptoms were measured using the Youth Self Report; parental chronic physical illness was reported during an interview. Associations were tested using linear regression analyses taking into account socio-demographic confounders. We also explored gender-interaction effects.

RESULTS

Having a chronically ill parent (n = 120; 14.3 %) was associated with more FSS in girls (B = 1.05, 95%CI = [0.23, 1.88], p = .013), but not in boys (sex-interaction: p = .013). In girls, an association was also found between parental chronic illness and more internalizing problems (B = 2.68, 95%CI = [0.41, 4.95], p = .021), but this association disappeared when FSSs were excluded from the Internalizing problem scores.

LIMITATIONS

The current study has a cross-sectional design and relied on self-reported parental chronic physical illness what may have induced misclassification.

CONCLUSION

Findings suggest that having a chronically ill parent is associated with more FSSs in adolescent girls and that this association is specific for FSSs instead of general internalizing problems. Girls with a chronically ill parent may profit from interventions to prevent the development of FSSs.

Higher self-perceived stress reactivity is associated with increased chronic pain risk

Self-perceived stress reactivity—how a person cognitively and emotionally responds to a stressor—is longitudinally associated with increased odds for the development of chronic pain.

Introduction:

Experiencing stress can contribute to unfavorable pain experiences, but outcomes vary across individuals. Evidence suggests that a person's specific reactivity to stressful events may influence pain responses. Previous studies measuring physiological stress reactivity have found associations with pain both clinically and in the laboratory. However, the time and cost required for testing physiological stress reactivity may limit clinical application.

Objective:

Self-reported perception of one's own stress reactivity has been shown to correlate with physiological stress reactivity in relation to health outcomes and may represent a valuable tool in clinical pain assessment.

Methods:

Using data from the Midlife in the US survey, we selected participants who did not have chronic pain at baseline (n = 1512) and who had data at follow-up 9 years later. Stress reactivity was assessed using a subscale of the Multidimensional Personality Questionnaire. We conducted a binary logistic regression to determine the odds of developing chronic pain, controlling for demographics and other health-related variables.

Results:

Results indicate that higher reported stress reactivity at baseline increased the odds of developing chronic pain at follow-up (odds ratio (OR) = 1.085, 95% confidence interval (CI) (1.021, 1.153), P = 0.008), with the only other significant predictor being the number of chronic conditions (OR = 1.118, 95% CI (1.045, 1.197), P = 0.001).

Conclusion:

Findings provide evidence for the predictive criterion validity of self-reported stress reactivity in the context of chronic pain risk. More generally, with increased need for virtual assessment and care, self-reported stress reactivity may be a useful, time-efficient, and cost-efficient tool for predicting pain outcomes in research and clinical contexts.

Cortisol and α-amylase awakening response in children and adolescents with functional neurological (conversion) disorder

OBJECTIVE

Stress system dysregulation is considered to have an important role in the aetiology of paediatric functional neurological (conversion) disorder. This study examined salivary cortisol and α-amylase awakening responses in children with functional neurological disorder to determine activation patterns of the hypothalamic-pituitary-adrenal axis and sympathetic system. A healthy cortisol awakening response involves a robust increase in cortisol within 30 minutes of awakening. Alpha-amylase awakening response is variable in children.

METHODS

Cortisol and α-amylase were measured in saliva from 32 patients with functional neurological disorder (26 girls and 6 boys, aged 11.3-16.1 years) and 31 healthy controls (23 girls and 8 boys, aged 8.6-17.7 years). Saliva samples were collected using a Salivette sampling device at two time points - upon awakening and 30 minutes after awakening.

RESULTS

Patients with functional neurological disorder showed a decrease in cortisol awakening response (-4 nmol.min/L) and controls showed an increase (107 nmol.min/L), t(55) = -.4.6, p < 0.001. Within the functional neurological disorder group, 57% showed an attenuated cortisol awakening response and 43% showed an obliterated/reversed cortisol awakening response: Cortisol awakening response was negatively correlated with adverse childhood experiences, r(58) = -0.6, p = 0.002, and subjective distress (total Depression Anxiety and Stress Scales score), r(58) = -0.4, p = 0.050. In controls, cortisol awakening response showed no correlation with adverse childhood experiences and a positive correlation with subjective distress, r(56) = 0.4, p = 0.023. Total cortisol remained similar between the functional neurological disorder and control group. No significant differences were observed between the functional neurological disorder and control group in any of the α-amylase analyses.

DISCUSSION

The results suggest dysregulation of the hypothalamic-pituitary-adrenal axis in children with functional neurological disorder. Hypothalamic-pituitary-adrenal dysregulation in children with functional neurological disorder may contribute to comorbid symptoms of fatigue, sleep disturbance and subjective loss of well-being because circadian rhythms and energy metabolism are disrupted. Hypothalamic-pituitary-adrenal dysregulation - and changes in glucocorticoid (cortisol) signalling at the molecular level - may also contribute to increased vulnerability for functional neurological disorder symptoms because of epigenetically mediated changes to neural networks implicated in functional neurological disorder.

Can the bodily distress syndrome (BDS) concept be used to assess functional somatic symptoms in adolescence?

OBJECTIVE

Bodily Distress Syndrome (BDS) represents a new research concept for adult patients with various functional somatic syndromes. We evaluated the utility of the BDS research concept and the associated BDS-25-checklist as a screening tool for diverse functional somatic symptoms (FSS) in adolescence by investigating: 1) the psychometric and factorial structures of the checklist, 2) symptom cluster patterns and 3) illness classification and associations with emotional psychopathology and sociodemographic factors.

METHODS

This cross-sectional study obtained data from the 16/17-year follow-up (N = 2542) of the general population Copenhagen Child Cohort 2000 (CCC2000). We used self-reported questionnaires to assess physical symptoms (the BDS-25 checklist), overall health (KidScreen), emotional psychopathology (Spence Children's Anxiety Scale; The Mood and Feelings Questionnaire), and illness worry (Whiteley-6 Index), and utilized data from Danish national registers to assess sociodemographic factors.

RESULTS

The BDS-25 checklist items displayed satisfactory psychometric data quality. Factor analyses revealed a similar four-factor model as reported in adults (factor loadings λ ≥0.5), representing distinct BDS symptom clusters: cardio-pulmonary, gastro-intestinal, musculoskeletal and general symptoms. Latent class analyses revealed a model with three latent classes, i.e. probable no to mild BDS, probable moderate, single-organ BDS and probable severe, multi-organ BDS, displaying acceptable class quality (Entropy = 0.904). Trend analyses revealed sociodemographic group differences across latent classes. Increased emotional psychopathology was associated with more pronounced BDS symptoms.

CONCLUSION

Our findings support the BDS concept with four symptom clusters and three illness severity groups (no BDS, single- organ and multi-organ BDS) to screen for FSS in adolescence.

Interoception, Stress, and Physical Symptoms in Stress-Associated Diseases

Abstract. The brain and peripheral bodily organs continuously exchange information. Exemplary, interoception refers to the processing and perception of ascending information from the body to the brain. Stress responses involve a neurobehavioral cascade, which includes the activation of peripheral organs via neural and endocrine pathways and can thus be seen as an example for descending information on the brain-body axis. Hence, the interaction of interoception and stress represents bi-directional communication on the brain-body axis. The main hypothesis underlying this review is that the dysregulation of brain-body communication represents an important mechanism for the generation of physical symptoms in stress-related disorders. The aims of this review are, therefore, (1) to summarize current knowledge on acute stress effects on different stages of interoceptive signal processing, (2) to discuss possible patterns of abnormal brain-body communication (i.e., alterations in interoception and physiological stress axes activation) in mental disorders and chronic physical conditions, and (3) to consider possible approaches to modify interoception. Due to the regulatory feedback loops underlying brain-body communication, the modification of interoceptive processes (ascending signals) may, in turn, affect physiological stress axes activity (descending signals), and, ultimately, also physical symptoms.

Feasibility of group-based acceptance and commitment therapy for adolescents (AHEAD) with multiple functional somatic syndromes: a pilot study

BACKGROUND

Recurrent and impairing functional somatic syndromes (FSS) are common in adolescents. Despite a high need for care, empirically supported treatments are lacking for youth. The aim of this uncontrolled pilot study was to assess feasibility and treatment potential of a new intervention with group-based Acceptance and Commitment Therapy (ACT) in a generic treatment approach for adolescents with multiple FSS.

METHODS

Twenty-one patients received 'ACT for Health in Adolescents' (AHEAD) (30 h), specifically developed for adolescents (aged 15-19 years) with moderate to severe FSS. Close relatives attended an information meeting to facilitate support of the patients throughout treatment. Treatment satisfaction was evaluated by means of self-report and relatives' impressions. Self-reported physical health at 3 months follow-up (FU) after end of treatment was the primary outcome whereas secondary outcomes included symptom burden, limitation due to symptoms, illness worry, emotional distress and physical and emotional symptoms. Treatment targets were assessed by measures on illness behaviour, illness perception and psychological inflexibility.

RESULTS

Nineteen patients (90.5%) completed the treatment with a high overall attendance rate of 93%. All would recommend the treatment to a friend with similar problems. Close relatives rated it valuable to participate in an information meeting. Patients' physical health improved significantly from assessment to FU with a clinically relevant mean change of 8.9 points (95% CI [5.4; 12.4]; SRM 0.91 [0.26;1.57]). Improvement was also seen on all secondary outcome measures, from assessment to FU. Maladaptive illness behaviours and perceptions as well as psychological inflexibility showed a significant decline from assessment to FU.

CONCLUSION

AHEAD was feasible and potentially efficacious and warrants testing in a larger clinical trial.

TRIAL REGISTRATION

Clinical Trials gov NCT04464447 , registration date July 9th, 2020. Retrospectively registered.

The effect of treatment regimens on salivary cortisol levels in patients with chronic musculoskeletal disorders

BACKGROUND

Increased levels of circulating cortisol have been associated with pain severity in patients with chronic musculoskeletal disorders (CMD). Little is known about the potential association between pain management and salivary cortisol alterations in CPM patients treated with different regimens.

OBJECTIVES

This prospective feasibility study aimed to determine the effect of two treatment regimens in comparison with sham therapy on pain intensity and disability and salivary cortisol concentration (SCC) in patients with CMD.

METHODS

Thirty patients were randomly assigned to 3 groups of 10: two experimental groups (A and B) and a control group (C). The experimental groups followed physiotherapy treatment (A) or acupuncture (B), while the control group (C) followed a sham therapy for 10 sessions. Pain data were collected using the Chronic Pain Grade (CPG) questionnaire and SCC was measured by enzyme-linked immunosorbent assay at pre- and posttreatment.

RESULTS

Repeated-measures analysis of variance showed that patients treated with acupuncture experienced greater decreases in pain intensity/pain disability (P < 0.05) than the physiotherapy and sham therapy groups. No statistical differences were found between the three groups for the SCC outcome variable. Bonferroni adjustments showed that the mean values of SCC were significantly decreased at posttreatment (P < 0.05) across the three groups.

CONCLUSION

There was a significant decrease in both pain and cortisol outcomes at posttreatment in patients with CMD. Because of the limitations of this study, we cannot draw conclusions regarding whether the lower SCC could be an indication of pain reduction in patients with CMD.

Stress-system activation in children with chronic pain: A focus for clinical intervention

Accumulating evidence indicates that psychological and neurophysiological processes interconnect and interact to activate the body's stress system and to trigger and maintain functional somatic symptoms. This study used the Early Life Stress Questionnaire, Depression Anxiety Stress Scales and biological markers (heart rate, heart rate variability, skin conductance, C-reactive protein (CRP) titre, respiratory rate, and accuracy and reaction time in an emotion-face identification task), to examine childhood adversity, psychological distress and stress-system activation in 35 children and adolescents (23 girls and 12 boys, 9-17 years old) disabled by chronic pain (vs two groups of age- and sex-matched healthy controls). Patients reported more early-life stress (U = 798.5, p = .026) and more psychological distress (U = 978, p < .001). They showed activation of the autonomic system: elevated heart rate (U = 862.5, p = .003), elevated electrodermal activity (U = 804.5, p = .024) and lower heart rate variability in the time domain (U = 380.5, p = .007) and frequency domain (U = 409.5, p = .017). The group showed an upward shift of CRP titres (with 75th and 90th CRP percentiles of 4.5 and 10.5 mg/L, respectively), suggesting the activation of the immune-inflammatory system. Elevated CRP titres were associated with elevated heart rate (p = .028). There were no differences in respiratory rate or in accuracy and reaction time in the emotion-face identification task. The results indicate that interventions for children and adolescents with chronic pain need a multidisciplinary mind-body approach that concurrently addresses psychological distress, physical impairment and stress-system dysregulation.

Positive affect and functional somatic symptoms in young adults

BACKGROUND

Functional Somatic Symptoms (FSS) are symptoms for which an underlying pathology cannot be found. High negative affect (NA) has been linked to the etiology of FSS, but little is known about the role of Positive Affect (PA).

OBJECTIVE

The aim of this study was to test if PA is related to current and future lower levels of FSS. We also examined the interactions between PA and NA, and PA and sex on FSS.

METHOD

Data from the Dutch Tracking Adolescents' Individual Lives Survey (TRAILS) cohort were used (N = 1247 cases, 60% females, mean age T5 = 22.2, T6 = 25.6). PA was measured with the PANAS schedule and FSS with the Adult Self Report questionnaire (ASR). A Principal Component Analysis (PCA) was performed on the physical complaints subscale of the ASR. Regression analyses with bootstrapping were performed to assess the associations and interactions.

RESULTS

PA had a significant negative association with current FSS when adjusted for NA, age, sex and socioeconomic status (B = -0.004; BCa 95% CI = [-0.006; -0.002]), but the association was not significant longitudinally. No interactions were found. In secondary analysis, PA was significantly related to the component "General Physical Symptoms" (B = -0.019; BCa 95% CI = [-0.0028; -0.011]) but not to the component "Gastrointestinal Symptoms" (B = -0.008; BCa 95% CI = [-0.016;0.001]) in the cross-sectional analysis.

CONCLUSION

In conclusion, high PA was significantly related to current lower levels of FSS, but the effect was small. Further research on individual variations in affect is needed to obtain more insight in their contribution to FSS.

Transitioning from acute to chronic pain: a simulation study of trajectories of low back pain

Background

Identifying how pain transitions from acute to chronic is critical in designing effective prevention and management techniques for patients’ well-being, physically, psychosocially, and financially. There is an increasingly pressing need for a quantitative and predictive method to evaluate how low back pain trajectories are classified and, subsequently, how we can more effectively intervene during these progression stages.

Methods

In order to better understand pain mechanisms, we investigated, using computational modeling, how best to describe pain trajectories by developing a platform by which we studied the transition of acute chronic pain.

Results

The present study uses a computational neuroscience-based method to conduct such trajectory research, motivated by the use of hypothalamic–pituitary–adrenal (HPA) axis activity-history over a time-period as a way to mimic pain trajectories. A numerical simulation study is presented as a “proof of concept” for this modeling approach.

Conclusions

This model and its simulation results have highlighted the feasibility and the potential of developing such a broader model for patient evaluations.

Blood CRP levels are elevated in children and adolescents with functional neurological symptom disorder

There is accumulating evidence that patients with functional neurological symptom disorder (FND) show activation of multiple components of the stress system-the hypothalamic-pituitary-adrenal axis, autonomic nervous system, and brain regions involved in arousal- and emotion-processing. This study aims to examine whether the immune-inflammatory component of the stress system is also activated. C-reactive protein (CRP) blood titre levels were measured in 79 children and adolescents with FND. CRP values ≥ 2 mg/L suggest low-grade inflammation. CRP values > 10 mg/L suggest a disease process. Sixty-six percent of subjects (n = 52) had CRP titres ≥ 2 mg/L. The upward shift in the distribution of CRP levels suggested low-grade inflammation (median CRP concentration was 4.60 mg/L, with 75th and 90th percentiles of 6.1 and 10.3 mg/L, respectively). Elevated CRP titres were not explained by sex, pubertal status, BMI, or medical factors. Confounder analyses suggested that history of maltreatment (χ² = 2.802, df = 1, p = 0.094, φ = 0.190; β = 2.823, p = 0.04) and a diagnosis of anxiety (χ² = 2.731, df = 1, p = 0.098, φ = 0.187; β = 4.520, p = 0.061) contributed to elevated CRP levels. Future research will need to identify the origins and locations of immune cell activation and the pathways and systems contributing to their activation and modulation. Because functional activity in neurons and glial cells-the brain's innate effector immune cells-is tightly coupled, our finding of elevated CRP titres suggests activation of the immune-inflammatory component of the brain's stress system. A more direct examination of inflammation-related molecules in the brain will help clarify the role of immune-inflammatory processes in FND.

Structural alterations in functional neurological disorder and related conditions: a software and hardware problem?

Functional neurological (conversion) disorder (FND) is a condition at the interface of neurology and psychiatry. A "software" vs. "hardware" analogy describes abnormal neurobiological mechanisms occurring in the context of intact macroscopic brain structure. While useful for explanatory and treatment models, this framework may require more nuanced considerations in the context of quantitative structural neuroimaging findings in FND. Moreover, high co-occurrence of FND and somatic symptom disorders (SSD) as defined in DSM-IV (somatization disorder, somatoform pain disorder, and undifferentiated somatoform disorder; referred to as SSD for brevity in this article) raises the possibility of a partially overlapping pathophysiology. In this systematic review, we use a transdiagnostic approach to review and appraise the structural neuroimaging literature in FND and SSD. While larger sample size studies are needed for definitive characterization, this article highlights that individuals with FND and SSD may exhibit sensorimotor, prefrontal, striatal-thalamic, paralimbic, and limbic structural alterations. The structural neuroimaging literature is contextualized within the neurobiology of stress-related neuroplasticity, gender differences, psychiatric comorbidities, and the greater spectrum of functional somatic disorders. Future directions that could accelerate the characterization of the pathophysiology of FND and DSM-5 SSD are outlined, including "disease staging" discussions to contextualize subgroups with or without structural changes. Emerging neuroimaging evidence suggests that some individuals with FND and SSD may have a "software" and "hardware" problem, although if structural alterations are present the neural mechanisms of functional disorders remain distinct from lesional neurological conditions. Furthermore, it remains unclear whether structural alterations relate to predisposing vulnerabilities or consequences of the disorder.

Use of respiratory rates and heart rate variability in the assessment and treatment of children and adolescents with functional somatic symptoms

Functional somatic symptoms (FSS) emerge when the stress system is activated in response to physical or emotional stress that is either chronic or especially intense. In such cases, the heightened state of physiological arousal and motor activation can be measured through biological markers. Our team have integrated the use of biological markers of body state - respiratory rate, heart rate (HR) and heart rate variability (HRV) measurements - as a way of helping families to understand how physical symptoms can signal activation of the body's stress systems. This study measured respiratory rates, HR and HRV in children and adolescents with FSS (and healthy controls) during baseline assessment to determine whether these biological markers were effective at differentiating patients with FSS. The study also implemented a biofeedback intervention during the assessment to determine whether patients with FSS were able to slow their respiratory rates and increase HRV. Patients with FSS had faster respiratory rates, faster HR, and lower HRV, suggesting activation of the autonomic nervous system coupled with activation of the respiratory motor system. Like controls, patients were able to slow their respiratory rates, but in contrast to controls, they were unable to increase their HRV. Our findings suggest that patients with FSS present in a state of physiological activation and struggle to regulate their body state. Patients with FSS are likely to need ongoing training and practice to regulate body state coupled with interventions that target regulatory capacity across multiple systems.

Education system stratification and health complaints among school-aged children

Research shows that the school environment is an important social determinant of health among children and adolescents. However, we know virtually nothing of the health consequences of national education systems and policies, for example the stratification of pupils by academic ability. This study aimed to investigate if education system stratification is related to self-reported psychological and somatic health complaints of pupils aged 11 to 15, and social inequalities in such health complaints. Survey data from the Health Behaviors of School-aged Children (HBSC) survey, covering 33 countries and more than 180 000 pupils in primary and lower secondary school, were used. Multilevel models showed that education system stratification was not associated with the average levels of health complaints of pupils, but cross-level interaction effects showed that stratification moderated the relationship between social background and health complaints, such that inequalities in health complaints were smaller in countries with more stratified systems. Moreover, this moderating effect was mediated by the school learning environment and social relations in school. Specifically, social inequalities in school pressure, academic self-concept, school climate, and school satisfaction were smaller in more stratified education systems, which in turn accounted for smaller inequalities in health complaints in these countries.

The association between herpes virus infections and functional somatic symptoms in a general population of adolescents. The TRAILS study

Background

FSS have been suggested to follow activation of the immune system, triggered by herpes virus infections. The aim of this study was to find out whether herpes virus infections were associated with the experience of FSS in adolescents, and whether this association was mediated by hsCRP, as a general marker of immune activation.

Methods

This study was performed in TRAILS, a large prospective population cohort of 2230 adolescents (mean age: 16.1 years, SD = .66, 53.4% girls). FSS were assessed using the somatic complaints subscale of the Youth Self-Report. FSS were analyzed as total scores and divided in two group clusters based on previous studies in this cohort. Levels of hsCRP and antibody levels to the herpes viruses HSV1, HSV2, CMV, EBV and HHV6 were assessed in blood samples at age 16. Also a value for pathogen burden was created adding the number of viruses the adolescents were seropositive for. Multiple regression analysis with bootstrapping was used to analyze the association between viral antibodies and pathogen burden, hsCRP and FSS scores.

Results

Antibody levels and pathogen burden were not associated with FSS total scores or FSS scores in both symptom groups. hsCRP was associated with the total FSS score (B = .02, 95% CI: .004 to .028, p = .01) and FSS score in the symptom group of headache and gastrointestinal complaints (B = .02, 95% CI: .001 to .039, p = .04).

Conclusion

Our study showed no association between herpes virus infections and FSS in general or specific FSS symptom clusters. A role for inflammatory processes in FSS development was supported by the significant association we found between hsCRP levels and FSS, especially in the symptom group of headache and gastrointestinal complaints.

The cross-sectional relation between medically unexplained physical symptoms (MUPS) and the Cortisol Awakening Response

OBJECTIVES

We aimed to assess the cross-sectional relation between levels of cortisol and specific symptom clusters, symptom severity and duration of symptoms in patients with medically unexplained physical symptoms (MUPS).

METHODS

Baseline data of a cohort of MUPS patients were used. We chose the Cortisol Awakening Response (CAR) as a cortisol parameter, using saliva samples. We used confirmatory factor analysis for the identification of 4 specific symptom clusters: (1) gastro-intestinal symptoms; (2) pain; (3) cardio-pulmonary symptoms; and (4) fatigue. For this factor analysis we used the Physical Symptom Questionnaire (PSQ), which assesses the occurrence and frequency of 51 physical symptoms. Symptom severity was measured with the Patient Health Questionnaire-15 (PHQ-15). Duration of symptoms was based on self-reported duration of top 3 symptoms. We performed multiple linear regression to assess relations between CAR and individual factor scores on symptom clusters, symptom severity and duration of symptoms.

RESULTS

Data from 296 patients (76% female) were included in the analyses. The majority of patients suffered from symptoms in multiple organ systems. Factor analysis confirmed that the model with 4 symptom clusters fitted our data. For the total study population, we found no significant relation between CAR and participants' factor scores on any of the symptom clusters. We also found no significant relations between CAR and severity or duration of symptoms.

CONCLUSION

Our results suggest that within a heterogeneous MUPS population there is no relation between CAR and symptom severity and duration. However, more studies are needed to confirm our findings.

Comparing group-based acceptance and commitment therapy (ACT) with enhanced usual care for adolescents with functional somatic syndromes: a study protocol for a randomised trial

INTRODUCTION

Functional somatic syndromes (FSS) are common in adolescents, characterised by severe disability and reduced quality of life. Behavioural treatments such as acceptance and commitment therapy (ACT) has shown promising results in children and adolescents with FSS, but has focused on specific syndromes such as functional pain. The current study will compare the efficacy of group-based ACT with that of enhanced usual care (EUC) in adolescents with a range of FSS operationalised by the unifying construct of multiorgan bodily distress syndrome (BDS).

METHODS AND ANALYSIS

A total of 120 adolescents aged 15-19 and diagnosed with multiorgan BDS, of at least 12 months duration, will be assessed and randomised to either: (1) EUC: a manualised consultation with a child and adolescent psychiatrist and individualised treatment plan or (2) manualised ACT-based group therapy plus EUC. The ACT programme consists of 9 modules (ie, 27 hours) and 1 follow-up meeting (3 hours). The primary outcome is physical health, assessed by an Short Form Health Survey (SF-36) aggregate score 12 months after randomisation. Secondary outcomes include self-reported symptom severity, symptom interference, depression and anxiety, illness worry, perceived stress and global improvement; as well as objective physical activity and bodily stress response measured by heart rate variability, hair cortisol and inflammatory biomarkers. Process measures are illness perception, illness-related behaviour and psychological flexibility.

ETHICS AND DISSEMINATION

The study is conducted in accordance with Helsinki Declaration II. Approval has been obtained from the Science Ethics Committee of the Central Denmark Region and the Danish Data Protection. The results will be sought to be published according to the CONSORT statement in peer-reviewed journals.

DISCUSSION

This is one of the first larger randomised clinical trials evaluating the effect of a group-based intervention for adolescents with a range of severe FSS.

TRIAL REGISTRATION NUMBER

NCT02346071; Pre-results.

Are Cardiac Autonomic Nervous System Activity and Perceived Stress Related to Functional Somatic Symptoms in Adolescents? The TRAILS Study

Objective

Stressors have been related to medically insufficiently explained or functional somatic symptoms (FSS). However, the underlying mechanism of this association is largely unclear. In the current study, we examined whether FSS are associated with different perceived stress and cardiac autonomic nervous system (ANS) levels during a standardized stressful situation, and whether these associations are symptom-specific.

Methods

We examined 715 adolescents (16.1 years, 51.3% girls) from the Dutch cohort study Tracking Adolescents’ Individual Lives Sample during the Groningen Social Stress Test (GSST). FSS were assessed by the Youth Self-Report, and clustered into a cluster of overtiredness, dizziness and musculoskeletal pain and a cluster of headache and gastrointestinal symptoms. Perceived stress levels (i.e. unpleasantness and arousal) were assessed by the Self-Assessment Manikin, and cardiac ANS activity by assessing heart rate variability (HRV-HF) and pre-ejection period (PEP). Perceived stress and cardiac ANS levels before, during, and after the GSST were studied as well as cardiac ANS reactivity. Linear regression analyses were used to examine the associations.

Results

Perceived arousal levels during (beta = 0.09, p = 0.04) and after (beta = 0.07, p = 0.047) the GSST, and perceived unpleasantness levels before (beta = 0.07, p = 0.048) and during (beta = 0.12, p = 0.001) the GSST were related to FSS during the past couple of months. The association between perceived stress and FSS was stronger for the FSS cluster of overtiredness, dizziness and musculoskeletal pain than for the cluster of headache and gastrointestinal symptoms. Neither ANS activity levels before, during, and after the GSST, nor maximal HF-HRV and PEP reactivity were related to FSS.

Conclusions

This study suggests that perceived stress levels during social stress are related to FSS, whereas cardiac ANS activity and reactivity are not related to FSS.

A low cortisol response to stress is associated with musculoskeletal pain combined with increased pain sensitivity in young adults: a longitudinal cohort study

Background

In this study, we investigated whether an abnormal hypothalamic-pituitary-adrenal (HPA) axis response to psychosocial stress at 18 years of age is associated with musculoskeletal (MS) pain alone and MS pain combined with increased pain sensitivity at 22 years of age.

Methods

The study sample included 805 participants from the Western Australian Pregnancy Cohort (Raine) Study who participated in the Trier Social Stress Test (TSST) at age 18 years. Number of pain sites, pain duration, pain intensity and pain frequency were assessed at age 22 to measure severity of MS pain. Cold and pressure pain thresholds were determined at age 22. Group-based trajectory modeling was applied to establish cortisol response patterns based on the TSST. Logistic regression was used to study the association of TSST patterns with MS pain alone and MS pain combined with increased cold or pressure pain sensitivity, adjusted for relevant confounding factors. All analyses were stratified by sex.

Results

The mean (standard deviation) age during the TSST was 18.3 (0.3) years, and during MS pain assessment it was 22.2 (0.6). Forty-five percent of the participants were female. Three cortisol response patterns were identified, with cluster 1 (34 % of females, 21 % of males) reflecting hyporesponse, cluster 2 (47 %, 54 %) reflecting intermediate response and cluster 3 (18 %, 24 %) reflecting hyperresponse of the HPA axis. MS pain was reported by 42 % of females and 33 % of males at age 22 years. Compared with females in cluster 2, females in cluster 1 had an increased likelihood of having any MS pain (odds ratio 2.3, 95 % confidence interval 1.0–5.0) and more severe MS pain (2.8, 1.1–6.8) if their cold pain threshold was above the median. In addition, females in cluster 1 had an increased likelihood (3.5, 1.3–9.7) of having more severe MS pain if their pressure pain threshold was below the median. No statistically significant associations were observed in males.

Conclusions

This study suggests that a hyporesponsive HPA axis at age 18 years is associated with MS pain at 22 years in young females with increased pain sensitivity.

Short report: Functional somatic symptoms are associated with perfectionism in adolescents

OBJECTIVE

The aim of this study is to investigate the influence of perfectionism on functional somatic symptoms (FSSs) in adolescents. It was hypothesized that perfectionism predicts higher levels of FSSs cross-sectionally and longitudinally, and that anxiety and depression mediate this relationship.

DESIGN

This prospective population-based study was part of the Dutch Tracking Adolescents' Individual Lives Survey (N=2230; 50.8% girls). Data from 1878 participants attending the third (T3) or fourth (T4) assessment wave were used (mean age T3: 16.2 (SD:0.7); mean age T4: 19.0 (SD:0.6)). Multiple regression and mediation analyses were performed in Mplus.

MAIN OUTCOME MEASURES

FSSs, perfectionism (i.e. the feeling one has to be perfect), anxiety and depression were assessed with the Youth Self-Report at the third and fourth wave.

RESULTS

Perfectionism was associated with a higher level of FSSs in adolescents, both cross-sectionally (B=0.11, 95%-CI: 0.08-0.14) and longitudinally (B=0.05, 95%-CI: 0.02-0.08). There was a small indirect effect of perfectionism on FSSs trough anxiety and depression (B=0.02, 95%-CI: 0.003-0.03, k(2)=0.02).

CONCLUSION

The results suggest that perfectionism predicts the course of FSSs with a small indirect effect of perfectionism on FSSs trough anxiety and depression. Further research is needed to clarify which aspects of perfectionism are particularly responsible for this effect.

Sexual abuse predicts functional somatic symptoms: an adolescent population study

The main aim of this study was to investigate the effect of childhood sexual abuse on medically not well explained or functional somatic symptoms (FSSs) in adolescents. We hypothesized that sexual abuse predicts higher levels of FSSs and that anxiety and depression contribute to this relationship. In addition, we hypothesized that more severe abuse is associated with higher levels of FSSs and that sexual abuse is related to gastrointestinal FSSs in particular. This study was part of the Tracking Adolescents' Individual Lives Survey (TRAILS): a general population cohort which started in 2001 (N=2,230; 50.8% girls, mean age 11.1 years). The current study uses data of 1,680 participants over four assessment waves (75% of baseline, mean duration of follow-up: 8 years). FSSs were measured by the Somatic Complaints subscale of the Youth Self-Report at all waves. Sexual abuse before the age of sixteen was assessed retrospectively with a questionnaire at T4. To test the hypotheses linear mixed models were used adjusted for age, sex, socioeconomic status, anxiety and depression. Sexual abuse predicted higher levels of FSSs after adjustment for age sex and socioeconomic status (B=.06) and after additional adjustment for anxiety and depression (B=.03). While sexual abuse involving physical contact significantly predicted the level of FSSs (assault; B=.08, rape; B=.05), non-contact sexual abuse was not significantly associated with FSSs (B=.04). Sexual abuse was not a stronger predictor of gastrointestinal FSSs (B=.06) than of all FSSs. Further research is needed to clarify possible mechanisms underlying relationship between sexual abuse and FSSs.

Glucocorticoid receptor gene methylation and HPA-axis regulation in adolescents. The TRAILS study

Early life adversity and psychopathology are thought to be linked through HPA-axis deregulation. Changes in methylation levels of stress reactivity genes such as the glucocorticoid receptor gene (NR3C1) can be induced by adversity. Higher NR3C1 methylation levels have been associated with a reduced NR3C1 expression, possibly leading to impaired negative feedback regulation of the HPA-axis. In this study we tested whether methylation levels of NR3C1 were associated with HPA-axis regulation, operationalized as cortisol responses. In 361 adolescents (mean age 16.1, SD=0.6), salivary cortisol samples were collected before, during, and after a social stress task, from which response measures (cortisol activation and recovery) were calculated. Higher NR3C1 methylation levels were associated with a flattened cortisol recovery slope, indicating a delayed recovery time. Cortisol response activation was not associated with NR3C1 methylation. These results suggest that methylation of NR3C1 may impair negative feedback of the HPA-axis in adolescents.

Interoception and stress

Afferent neural signals are continuously transmitted from visceral organs to the brain. Interoception refers to the processing of visceral-afferent neural signals by the central nervous system, which can finally result in the conscious perception of bodily processes. Interoception can, therefore, be described as a prominent example of information processing on the ascending branch of the brain–body axis. Stress responses involve a complex neuro-behavioral cascade, which is elicited when the organism is confronted with a potentially harmful stimulus. As this stress cascade comprises a range of neural and endocrine pathways, stress can be conceptualized as a communication process on the descending branch of the brain–body axis. Interoception and stress are, therefore, associated via the bi-directional transmission of information on the brain–body axis. It could be argued that excessive and/or enduring activation (e.g., by acute or chronic stress) of neural circuits, which are responsible for successful communication on the brain–body axis, induces malfunction and dysregulation of these information processes. As a consequence, interoceptive signal processing may be altered, resulting in physical symptoms contributing to the development and/or maintenance of body-related mental disorders, which are associated with stress. In the current paper, we summarize findings on psychobiological processes underlying acute and chronic stress and their interaction with interoception. While focusing on the role of the physiological stress axes (hypothalamic-pituitary-adrenocortical axis and autonomic nervous system), psychological factors in acute and chronic stress are also discussed. We propose a positive feedback model involving stress (in particular early life or chronic stress, as well as major adverse events), the dysregulation of physiological stress axes, altered perception of bodily sensations, and the generation of physical symptoms, which may in turn facilitate stress.

Ghrelin-reactive immunoglobulins and anxiety, depression and stress-induced cortisol response in adolescents. The TRAILS study

BACKGROUND

Ghrelin, a hunger hormone, has been implicated in the regulation of stress-response, anxiety and depression. Ghrelin-reactive immunoglobulins (Ig) were recently identified in healthy and obese humans showing abilities to increase ghrelin's stability and orexigenic effects. Here we studied if ghrelin-reactive Ig are associated with anxiety and depression and with the stress-induced cortisol response in a general population of adolescents. Furthermore, to test the possible infectious origin of ghrelin-reactive Ig, their levels were compared with serum IgG against common viruses.

METHODS

We measured ghrelin-reactive IgM, IgG and IgA in serum samples of 1199 adolescents from the Dutch TRAILS study and tested their associations with 1) anxiety and depression symptoms assessed with the Youth Self-Report, 2) stress-induced salivary cortisol levels and 3) IgG against human herpesvirus 1, 2, 4 and 6 and Influenza A and B viruses.

RESULTS

Ghrelin-reactive IgM and IgG correlated positively with levels of antibodies against Influenza A virus. Ghrelin-reactive IgM correlated negatively with antibodies against Influenza B virus. Ghrelin-reactive IgM correlated positively with anxiety scores in girls and ghrelin-reactive IgG correlated with stress-induced cortisol secretion, but these associations were weak and not significant after correction for multiple testing.

CONCLUSION

These data indicate that production of ghrelin-reactive autoantibodies could be influenced by viral infections. Serum levels of ghrelin-reactive autoantibodies probably do not play a role in regulating anxiety, depression and the stress-response in adolescents from the general population.

Cohort Profile Update: the TRacking Adolescents' Individual Lives Survey (TRAILS)

TRAILS consists of a population cohort (N = 2230) and a clinical cohort (N = 543), both of which were followed from about age 11 years onwards. To date, the population cohort has been assessed five times over a period of 11 years, with retention rates ranging between 80% and 96%. The clinical cohort has been assessed four times over a period of 8 years, with retention rates ranging between 77% and 85%. Since the IJE published a cohort profile on the TRAILS in 2008, the participants have matured from adolescents into young adults. The focus shifted from parents and school to entry into the labour market and family formation, including offspring. Furthermore, psychiatric diagnostic interviews were administered, the database was linked to a Psychiatric Case Registry, and the availability of genome-wide SNP variations opened the door to genome-wide association studies regarding a wide range of (endo)phenotypes. With some delay, TRAILS data are available to researchers outside the TRAILS consortium without costs; access can be obtained by submitting a publication proposal (see www.trails.nl).

Corticotropin (ACTH)-reactive immunoglobulins in adolescents in relation to antisocial behavior and stress-induced cortisol response. The TRAILS study

Elevated levels of corticotropin (ACTH)-reactive immunoglobulins (ACTH IgG) were found in males with conduct disorder, suggesting their involvement in the biology of antisocial behavior. We first aimed to confirm these findings in a large general population sample of adolescents. Secondly, we studied the association between ACTH IgG levels and hypothalamic-pituitary-adrenal (HPA) axis response to stress. Free and total ACTH IgG levels were measured in sera of 1230 adolescents (15-18 years). HPA axis activity was determined by measuring salivary cortisol before, during, and after a social stress test. Antisocial behavior was assessed using the Antisocial Behavior Questionnaire. ACTH peptide and IgG affinity kinetics for ACTH were assayed in a subsample of 90 adolescents selected for high or low ACTH IgG levels. In boys, higher total ACTH IgG levels were associated with higher antisocial behavior scores (β=1.05, p=0.04), especially at high levels of free ACTH IgG. In girls, antisocial behavior was associated with low free ACTH IgG levels (β=-0.20, p=0.04). Stress-induced cortisol release was associated with free ACTH IgG in boys (βareaunderthecurve=-0.67, p<0.01), and with total ACTH IgG in girls (βrecovery=0.84, p=0.05). The affinity kinetics assay showed that ACTH IgG association rates were lower in both boys and girls with high ACTH IgG levels. These data show that ACTH IgG levels are related to antisocial behavior and HPA axis response to stress in adolescents. The mechanisms behind these associations, including different ACTH binding properties of IgG in subjects with antisocial behavior, deserve further attention.

Functional somatic symptoms in childhood and adolescence

PURPOSE OF REVIEW

Functional somatic symptoms (FSS) are common in children and adolescents, but explanatory models that synthesize research findings are lacking. This article reviews the studies published from January 2012 to March 2013 that investigate the neurophysiological mechanisms that may underlie FSS.

RECENT FINDINGS

Studies from diverse medical disciplines suggest that FSS are associated with functional differences in hypothalamic-pituitary-adrenal function, imbalances in vagal-sympathetic tone, upregulation of immune-inflammatory function, and primed cognitive-emotional responses that serve to amplify reactivity to threatening stimuli, thereby contributing to the subjective experience of somatic symptoms.

SUMMARY

FSS appear to reflect dysregulations of the stress system. When seemingly disparate research findings are interpreted together within an overarching 'stress-system' framework, a coherent explanatory model begins to emerge.