The unifying diagnostic construct of bodily distress syndrome (BDS) was confirmed in the general population

Is reduced heart rate variability associated with functional somatic disorders? A cross-sectional population-based study; DanFunD

OBJECTIVES

It has been hypothesised that functional somatic disorders (FSD) could be initiated by sympathetic predominance in the autonomic nervous system as measured by low heart rate variability (HRV). Earlier studies on the association between HRV and FSD are small case-control studies hampered by selection bias and do not consider the great overlap between the various FSDs. The aim of the present study is to assess any associations between HRV and various FSDs and whether chronic stress confounds such an association.

DESIGN

A cross-sectional general population-based study.

SETTING

The Danish Study of Functional Somatic Disorders conducted 2013-2015 in 10 municipalities in the western part of Greater Copenhagen, Denmark.

PARTICIPANTS

A total of 6891 men and women aged 18-72 years were included in the analyses after exclusion of 602 persons with missing HRV data. Various delimitations of FSD (chronic fatigue, chronic widespread pain, irritable bowel and bodily distress syndrome) were identified by validated questionnaires and diagnostic interviews. HRV parameters in time and frequency domains were calculated from successive beat-to-beat heart rate (HR) data using the 'E-motion' HR monitor device during 7 min of supine rest. Chronic stress was assessed by Cohen's self-perceived stress scale.

OUTCOME MEASURES

Logistic regression analyses were used to calculate possible associations between the various delimitations of FSD and HRV adjusting for chronic stress.

RESULTS

Persons with FSD had a slightly higher mean HR and lower HRV as measured by time domain parameters, whereas associations with frequency domain parameters were not consistent. Adjusting for chronic stress attenuated associations slightly.

CONCLUSION

The study supports a sympathetic predominance in persons with FSD, which could not be entirely explained by chronic stress. However, it is not possible to conclude whether the association is a causal factor to or a consequence of FSD.

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.

Lipid metabolism and functional somatic disorders in the general population. The DanFunD study

OBJECTIVES

Earlier studies on the association between plasma lipid profiles and functional somatic disorders (FSD) are mainly small case control studies hampered by selection bias and do not consider the great overlap between the various FSDs. The aim of the present study was to investigate the associations between various FSDs and plasma lipid profiles (total cholesterol, HDL cholesterol, non-HDL cholesterol and triglycerides) in a large, unselected population.

DESIGN

A cross-sectional general population-based study.

SETTING

The Danish Study of Functional Somatic Disorders (DanFunD) conducted in 2011-2015 in 10 municipalities in the western part of greater Copenhagen, Denmark.

PARTICIPANTS

A total of 8,608 men and women aged 18-76 years were included in the analyses. Various delimitations of FSD such as chronic fatigue, chronic widespread pain, irritable bowel, and bodily distress syndrome were measured using validated self-administrated questionnaires. Lipid parameters were measured from fasting plasma samples using colorimetric slide methods with Vitros 4600/5600 Ortho Clinical Diagnostics.

OUTCOME MEASURES

Logistic regression analyses were used to calculate possible associations between plasma lipids and the various delimitations of FSD. Associations are presented by OR (95% CI) and shown in boxplots.

RESULTS

We found a positive association between bodily distress syndrome and triglycerides and non-HDL cholesterol and a negative association with HDL-cholesterol, but no consistent association with total cholesterol. A similar pattern was observed for persons with chronic fatigue, and to some degree for persons with chronic widespread pain, whereas persons with irritable bowel did not show a clear association with the lipid profiles.

CONCLUSION

This is the first major study on plasma lipid profiles and FSD indicating an association between some delimitations of FSD and an unfavorable lipid profile. Due to the cross-sectional design, it cannot be determined whether the findings are consequences or determinants of FSD. Further studies-preferable prospective studies-are needed.

Neuroticism, perceived stress, adverse life events and self-efficacy as predictors of the development of functional somatic disorders: longitudinal population-based study (DanFunD)

BACKGROUND

Functional somatic disorder (FSD) is a unifying diagnosis that includes functional somatic syndromes such as irritable bowel, chronic widespread pain (CWP) and chronic fatigue. Several psychological factors are associated with FSD. However, longitudinal population-based studies elucidating the causal relationship are scarce.

AIMS

To explore if neuroticism, perceived stress, adverse life events (ALEs) and self-efficacy can predict the development of FSD over a 5-year period.

METHOD

A total of 4288 individuals who participated in the DanFunD baseline and 5-year follow-up investigations were included. FSD was established at both baseline and follow-up, with symptom questionnaires and diagnostic interviews. Neuroticism was measured with the short-form NEO Personality Inventory, perceived stress with the Cohen's Perceived Stress Scale, ALEs with the Danish version of the Cumulative Lifetime Adversity Measure and self-efficacy with the General Self-Efficacy Scale. Associations were investigated with multiple logistic regression models.

RESULTS

Perceived stress predicted incident FSD, irritable bowel, CWP and chronic fatigue (odds ratios: 1.04-1.17). Neuroticism predicted incident FSD and chronic fatigue (odds ratios: 1.03-1.16). ALEs predicted incident FSD, CWP and chronic fatigue (odds ratios: 1.06-1.18). An increase in perceived stress from baseline to follow-up was associated with incident FSD, irritable bowel, CWP and chronic fatigue (odds ratios: 1.05-1.22). Contrary, an increase in self-efficacy seemed to be a protective factor (odds ratios: 0.89-0.99).

CONCLUSIONS

High neuroticism, high perceived stress and a high number of ALEs are risk factors for the development of FSD. Particularly perceived stress seems to be an important contributor to the onset of FSD.

The distribution of somatic symptom disorder and bodily distress syndrome in general hospital outpatients in China: A multicenter cross-sectional study

OBJECTIVE

To investigate the distribution of somatic symptom disorder (SSD) and bodily distress syndrome (BDS) and analyze the differences in psychosocial characteristics of patients with the two diagnoses.

METHODS

A total of 694 general hospital outpatients completed the diagnostic interviews for SSD and BDS, and a set of questionnaires evaluating their psychosocial characteristics. A secondary analysis of these data is done.

RESULTS

SSD and BDS had a moderate overlap (kappa value = 0.43). Patients who fulfilled both SSD and BDS diagnosis showed significantly higher levels of symptom-related psychological distress (SSD-12), somatic symptom severity (PHQ-15), depression (PHQ-9), and general anxiety (GAD-7), as well as lower mental and physical quality of life (SF-12) compared to patients with neither diagnosis and patients with only one diagnosis. Patients with either diagnosis were associated with significantly higher psychosocial impairments as compared to those with neither diagnosis. Patients who only met SSD had higher SSD-12 scores, whereas those with only BDS had higher PHQ-15 scores (p<0.001).

CONCLUSIONS

SSD and BDS appear to represent somewhat different psychopathologies, with SSD more associated with psychological distress and BDS associated with greater experience of somatic symptoms. Patients fulfilling both diagnosis show higher symptom severity in various psychosocial aspects.

Are Sexual Assaults Related to Functional Somatic Disorders? A Cross-Sectional Study

An increasing number of sexual assaults (SAs) are being reported. This study investigated associations between SA and FSD, conceptualized as bodily distress syndrome (BDS), and five functional somatic syndromes (FSSs): chronic widespread pain (CWP), irritable bowel (IB), chronic fatigue (CF), multiple chemical sensitivity (MCS), and whiplash-associated disorder (WAD). Participants (n = 7493) from the population-based cohort Danish Study of Functional Disorders (DanFunD) completed questionnaires on FSD, emotional distress, SA, and sociodemographics. Risk ratios (RRs) for each FSD and emotional distress were calculated in nine models with SA as the primary exposure using generalized linear models with binomial family and log link and were adjusted for other potential risk factors. The results showed that SA was associated with single-organ FSD (RR = 1.51; 95% CI = 1.22-1.87), multi-organ FSD (RR = 3.51; 95% CI = 1.89-6.49), CWP (RR = 1.28; 95% CI = 0.83-1.98), IB (RR = 2.00; 95% CI = 1.30-3.07), CF (RR = 1.81; 95% CI = 1.42-2.32), WAD (RR = 2.62; 95% CI = 1.37-5.03), MCS (RR = 3.04; 95% CI = 1.79-5.17), emotional distress (RR = 1.75; 95% CI = 1.21-2.54), and health anxiety (RR = 1.65; 95% CI = 1.10-2.46). Overall, SA victims experienced significantly more somatic symptoms than individuals not exposed to SA. Adjusting for physical and emotional abuse did not change the observed associations. Our results suggest a large impact of SA on the overall somatic and mental health of SA victims. Due to the cross-sectional study design, further studies are required.

Managing pain in irritable bowel syndrome: current perspectives and best practice

INTRODUCTION

Irritable bowel syndrome (IBS) is characterized by chronic symptoms (>6 months) of abdominal pain in combination with a disturbed bowel habit. There is an association between the intensity of abdominal pain and the need for health care utilization. A bidirectionally disordered gut-brain interaction is central in the pathophysiology of IBS where a number of factors, gastrointestinal and non-gastrointestinal, can contribute to the illness experience. In order to treat abdominal pain in IBS, mapping these factors in a multidimensional clinical profile is helpful.

AREAS COVERED

This review covers basic epidemiology and pathophysiology of abdominal pain in IBS, the diagnostic approach, and a multidimensional treatment model where the management of abdominal pain is in focus.

EXPERT OPINION

A personalized treatment of abdominal pain in IBS is possible in patients who understand the diagnosis, the potential of therapies used, and where a good continuity in the patient-doctor relationship is established.

Social position and functional somatic disorders: The DanFunD study

BACKGROUND AND AIM

It is generally accepted that functional somatic disorders (FSDs) are a product of biological, psychological, and social factors. Social position might be part of this complex, but the literature on this issue is currently heterogeneous and inconsistent. The aim of the present study was - in a population-based cohort - to test the hypothesis that lower social position would be associated with higher a risk of FSD.

METHOD

The association between social position and FSD was examined in a cross-sectional study with various measures of social position (education as measured by vocational training; employment; cohabitation; subjective social status) and delimitations of FSD (irritable bowel syndrome, chronic fatigue syndrome, fibromyalgia, bodily distress syndrome, and symptom profiles). The associations were analyzed using logistic regressions to calculate odds ratios and 95% confidence intervals. Each social measure was analyzed independently and was adjusted for age and sex.

RESULTS

Lower levels of vocational training, being unemployed, and living alone were associated with higher risk of FSD, regardless of the FSD delimitation. There was also a significant negative association between subjective evaluated social status and FSD. The associations remained after multiple adjustments, and seemed to be strongest for the more severe FSD-types.

CONCLUSIONS

Lower social position is associated with higher risk of FSD, especially the more severe FSD delimitations, which might constitute an especially vulnerable group. However, the mechanisms behind the relations remain unknown.

High Perceived Stress and Low Self-Efficacy are Associated with Functional Somatic Disorders: The DanFunD Study

Objective

Several psychological factors have been proposed to be associated with functional somatic disorders (FSD) including functional somatic syndromes, such as irritable bowel, chronic widespread pain, and chronic fatigue. However, large randomly selected population-based studies of this association are sparse. This study aimed to investigate the association between FSD and perceived stress and self-efficacy, respectively, and to investigate if FSD differed from severe physical diseases on these aspects.

Methods

This cross-sectional study included a random sample of the adult Danish population (n = 9656). FSD were established using self-reported questionnaires and diagnostic interviews. Perceived stress was measured with Cohen's Perceived Stress Scale and self-efficacy with the General Self-Efficacy Scale. Data were analysed with generalized linear models and linear regression models.

Results

FSD were associated with higher perceived stress and lower self-efficacy, especially for the multi-organ and the general symptoms/fatigue FSD types and for chronic fatigue. However, controlling for the personality trait neuroticism altered the associations with self-efficacy so it became insignificant. The analysis did not support an important interaction between perceived stress and self-efficacy on the likelihood of having FSD. Individuals with FSD presented levels of perceived stress that were not equal, ie higher, to those in individuals with severe physical diseases.

Conclusion

FSD were positively associated with perceived stress and negatively associated with self-efficacy. Our study may point to stress being part of the symptomatology of FSD. This underlines the severity of having FSD and stresses the relevance of the resilience theory in the understanding of the condition.

Coping strategies among individuals with multiple physical symptoms: A general population-based cross-sectional study

OBJECTIVE

Coping has been suggested as a perpetuating factor for physical symptoms. The aim of this study was to examine the use of the coping strategies approach, resignation, and diversion in individuals with multiple physical symptoms according to the construct of Bodily Distress Syndrome (BDS).

METHODS

This cross-sectional study was part of the nationwide web-based survey Danish Symptom Cohort (DaSC). In total, 100,000 individuals were invited to participate, and individuals eligible for the present study were respondents aged 20-64 years without a current or recent pregnancy. Multiple physical symptoms were identified using the BDS checklist, and coping was assessed by the Brief Approach/Avoidance Coping Questionnaire. Statistical analyses included descriptive statistics and multinomial and logistic regression.

RESULTS

A total of 35,810 respondents were included in the study, of which 8512 (23.8%) fulfilled the criteria for having multiple physical symptoms. This group of respondents had lower coping scores on approach and higher coping scores on resignation and diversion compared with the non-BDS group. The regression analyses showed that high scores on approach were associated with a lower probability of having multiple symptoms (adjusted OR 0.92, 95% CI: 0.91-0.92), whereas high scores on diversion and resignation were associated with a higher probability of having multiple symptoms (adjusted OR 1.10; 95% CI: 1.09-1.11 and adjusted OR 1.19; 95% CI: 1.18-1.20, respectively).

CONCLUSION

The study supports the hypothesis that experiencing multiple physical symptoms is associated with certain coping strategies. This is relevant knowledge for health care professionals who will be treating this patient group.

Internet-delivered treatment for patients suffering from severe functional somatic disorders: Protocol for a randomized controlled trial

Background

Functional somatic disorders (FSDs) with symptoms from multiple organs, i.e., multi-system type, are common in the general population and may lead to disability and reduced quality of life. Evidence for efficient treatment programs has been established, however, there is a need for making treatments accessible to a larger group of patients. Internet-delivered therapy has become prevalent and has proven as effective as face-to-face therapy, while providing a flexible and easily accessible treatment alternative. The aim of the current study is to compare the efficacy of the therapist-assisted internet-delivered treatment program One step at a time (OneStep) with the internet-delivered self-help program Get started (GetStarted).

Methods

A total of 166 participants aged 18-60 years diagnosed with multi-system FSD will be assessed and randomized to either 1) OneStep: a 14-week program consisting of 11 treatment modules based on principles from cognitive behavioural therapy or 2) GetStarted consisting of 1 module on psychoeducation. The primary outcome is physical health, assessed by a Short Form Health Survey (SF-36) aggregate score of the subscales vitality, physical functioning, and bodily pain 3 months after end-of-treatment and self-reported improvement assessed by the Clinical Global Improvement Scale. Secondary outcomes include symptom load, depression, anxiety, and illness worry. Process measures include emotional distress, illness perception, illness behaviour, and symptom interference.

Conclusions

This study is the first study to test an internet-delivered treatment program for FSD, multi-system type and has the potential to show the importance of making evidence-based internet-delivered treatment for FSD more accessible.

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.

Experiences of patients with fibromyalgia at a Finnish Health Centre: A qualitative study

Background

Fibromyalgia is a functional syndrome. Despite recent findings, there is still considerable uncertainty about its diagnostic process.

Objectives

This study aimed to explore patients’ experiences with fibromyalgia during the diagnostic process in primary health care. Moreover, we tried to determine how diagnostic consultation could be improved.

Methods

This study is based on data from patients with fibromyalgia in a primary health care study conducted in Nokia, Finland. Patients with fibromyalgia were identified from electronic medical records. Focus-group participants with fibromyalgia diagnoses were selected using a purposive sampling method to gather a maximum variation sample. Qualitative thematic analysis was used for the coded data from four focus-group discussions in 2018. A description of the coding tree was provided and researchers organised the codes. Finally, all researchers identified themes from the data.

Results

The main unifying entities were the uncertainty and contradictions fibromyalgia patients faced on several occasions. Physicians sometimes offered other diagnoses – like depression – as an explanation for the symptoms, or used repetitive tests to eliminate other possible diagnoses. Furthermore, patients expressed their wishes for a holistic, empathetic, and up-to-date approach to their symptoms.

Conclusion

In our interviews, a good doctor-patient relationship and continuity of care were necessary, as were the physician’s attitude and knowledge of fibromyalgia. Our findings also suggest avoiding repeated or unnecessary rule-out tests and the overdiagnosis of psychiatric disorders is necessary.

A multicenter study of bodily distress syndrome in Chinese outpatient hospital care: prevalence and associations with psychosocial variables

BACKGROUND

Bodily distress syndrome (BDS) is a new, empirical-based diagnosis of functional somatic symptoms. This study aimed to explore the prevalence of BDS and its association with psychosocial variables in a Chinese clinical population.

METHODS

A multicentre cross-sectional study of 1269 patients was conducted in 9 different Chinese tertiary outpatient hospitals. The BDS was identified by trained interviewers face-to face, based on a brief version of the Schedules for Assessment in Neuropsychiatry (RIFD) and the BDS Checklist-25. Sociodemographic data and further information were characterised from psychometric questionnaires (The Patient Health Questionnaire-15, the Patient Health Questionnaire-9, the General Anxiety Disorder-7, the Whiteley scale-8) .

RESULTS

Complete data were available for 697 patients. The prevalence of BDS was 26.8% (95% confidence interval (CI): 23.5-30.1). Among the participants, 5.8% (95% CI: 4.1-7.6) fulfilled the criteria for single-organ BDS, while 20.9% (95%CI: 17.9-24.0) had multi-organ BDS. Comparison of the PHQ-15, PHQ-9, GAD-7, and WI-8 scores revealed higher scores on all dimensions for patients with BDS. In a binary logistic regression analysis, BDS was significantly associated with increased health-related anxiety (WI-8) and depression (PHQ-9). The explained variance was Nagelkerke's R² = 0.42.

CONCLUSIONS

In China, the BDS is a common clinical condition in tertiary outpatient hospital settings with high prevalence, and is associated with health anxiety and depressive symptoms. In this clinical population, the severe multi-organ subtype of BDS was the most frequent.

Neuroticism and adverse life events are important determinants in functional somatic disorders: the DanFunD study

Several psychological factors have been proposed to be associated with functional somatic disorders (FSD). However, large population-based studies investigating the importance of both personality and adverse life events (ALE) are sparse. This study aimed to investigate the association between FSD and neuroticism and the accumulated number of ALE, respectively. This cross-sectional study included a random sample of the adult Danish population (N = 7493). FSD were established by means of self-reported questionnaires and diagnostic interviews. Neuroticism was measured with the Danish version of the short-form NEO Personality Inventory. ALE were measured with the Danish version of the Cumulative Lifetime Adversity Measure. Strong positive associations were found between neuroticism and FSD, and ALE and questionnaire-based FSD. For interview-based FSD, strong positive associations were found for FSD, multi-organ type, and for the subtype of the general symptoms. The level of self-efficacy did not modify these associations, and no moderating effect of neuroticism and ALE in combination on the probability of having FSD was found. FSD were strongly associated with both neuroticism and the accumulated number of ALE, and these associations were not modified by self-efficacy. In combination, neuroticism and ALE did not have a moderating effect on the probability of having FSD.

Association between infections and functional somatic disorders: a cross-sectional population-based cohort study

OBJECTIVES

It has been suggested that infections can trigger functional somatic disorders (FSD). However, current evidence is limited by inconsistent findings in smaller studies conducted in clinical settings within selected populations and short follow-up times. We aimed to test the hypothesis that former infections are associated with FSD using data from nationwide registries and a large population-based cohort study, the Danish Study of Functional Disorders study.

DESIGN

FSD cases were identified in a cross-sectional population-based cohort and linked retrospectively to former hospital contacts with infections identified in the Danish National Patient Registry. The associations between FSD and former infections within 17 years were analysed using logistic regressions to calculate ORs and 95% CIs adjusted for age, sex and subjective social status.

SETTING

A population-based cohort in Denmark examined between 2011 and 2015.

PARTICIPANTS

A total of 9656 men and women aged 18-76 years.

MAIN OUTCOME MEASURES

FSD measured by various delimitations, including bodily distress syndrome (BDS), irritable bowel (IB), chronic fatigue (CF), chronic widespread pain (CWP), and multiple chemical sensitivity (MCS).

RESULTS

Overall, infections were associated with increased risk of all delimitations of FSD. The associations were more pronounced for multisystemic FSD. The number of prior infections increased the risk in a dose-response manner (p<0.0001). Bacterial but not viral infections were significantly associated with BDS (OR 1.69 (95% CI 1.46 to 1.96)), IB (OR 1.41 (95% CI 1.06 to 1.88)), CWP (OR 1.47 (95% CI 1.13 to 1.90)) and CF (OR 1.62 (95% CI 1.34 to 1.96)), but not MCS.

CONCLUSION

Former infections leading to hospital contacts were associated with a higher risk of having FSD. These associations were more pronounced for bacterial than viral infections, and more infections increased the risk in a dose-response manner. These results tend to support the idea that severe infections could play a role in FSD.

Examine the public health impacts of functional somatic disorders using the DanFunD study

Background: Persistent physical symptoms (e.g. pain, fatigue) are prevalent in the population and some persons may develop a functional somatic disorder (FSD). We still need to explore the limits between general bodily sensations and FSD, and great controversies exist as regard delimitation, occurrence, risk factors, prognosis, and costs of FSD in the general population. This is mainly due to the lack of focused, sufficient powered, population-based epidemiological studies. Material and Methods: The DanFunD study is the largest focused population-based study on FSD and has the potential to answer these crucial questions regarding the FSD disorders. DanFunD has its origin in the Copenhagen area of Denmark and was initiated in 2009 by an interdisciplinary team of researchers including basic scientists, clinical researchers, epidemiologists, and public health researchers. A population-based cohort of nearly 10,000 people have filled in detailed questionnaires, gone through a thorough health examination, and a biobank is established. The cohort was re-examined after five years. Results:The prevalence of FSD in the Danish population is about 10-15% and is twice as common in women as in men. Persons with FSD report impaired daily activities and low self-perceived health, which qualifies FSD as a major public health problem. The research plan to unravel the risk factors for FSD employs a bio-psycho-social approach according to a detailed plan. Preliminary results are presented, and work is in progress. Likewise, plans for assessing prognosis and health care costs are provided. Conclusion: We invite researchers in the field to collaborate on this unique data material.

Are study populations in trials of antidepressants and psychotherapy comparable? A retrospective case study of two parallel running trials for multi- organ functional somatic disorder

This study retrospectively compares two previous parallel running, randomized, controlled trials of pharmacotherapy (imipramine) and psychotherapy (acceptance and commitment therapy) for multi-organ functional somatic disorder (FSD). Differences in demographics, psychiatric comorbidity, illness severity, and illness duration associated with eligibility for the two trials and patients' willingness to participate are explored using linear or binary regression models. 418 patients with multi-organ FSD was included. We found that 377 (95%) were eligible for psychotherapy and 257 patients (61%) for pharmacotherapy. Patients eligible for pharmacotherapy were less severely impaired, less often received disability pension, reported shorter illness duration and experienced less psychological distress than patients eligible for psychotherapy. Whilst exclusion criteria for both trials differed markedly, it was not possible to clearly identify patient or illness characteristics associated with patients' willingness to participate. The study showed that trial-specific exclusion criteria led to the selection of less complex and less severely impaired patients in the pharmacological trial in this sample of multi-organ FSD. Our findings have important implications for the interpretation and comparability of RCT results of different treatments in multi-organ FSD and may point to some common flaws in study design and interpretation of pharmacological vs. psychotherapeutic intervention trials in psychiatry.

Early Psychological Interventions for Somatic Symptom Disorder and Functional Somatic Syndromes: A Systematic Review and Meta-Analysis

OBJECTIVE

Psychological treatments for somatic symptom disorder and functional somatic syndromes (SSD/FSS) achieve moderate effects only, potentially because of the high chronicity in these patients. Therefore, we aimed to evaluate whether early treatment, that is, treatment in populations at risk or with recent onset, improves outcome.

METHODS

We conducted a systematic review and meta-analysis of (cluster-)randomized controlled trials evaluating early psychological interventions in the prevention and treatment of SSD/FSS in adults compared with inactive control conditions, standard care, or placebo. Individuals at risk for SSD/FSS, suffering from subthreshold symptoms or new onsets of SSD/FSS, or presenting with SSD/FSS for the first time were included.

RESULTS

We identified 30 eligible studies, mostly examining pain-related conditions. Interventions were diverse, ranging from bibliotherapy to cognitive-behavioral therapy. We found positive effects on depression post-treatment (Hedges' g = 0.12 [95% confidence interval = 0.03-0.2], k = 5) as well as on somatic symptom severity (g = 0.25 [0.096-0.41], k = 17) and health care utilization (g = 0.31 [0.18-0.44], k = 3) at follow-up. However, because of a high risk of bias, sensitivity to corrections for meta-bias, and missing outcome data, findings should be interpreted cautiously.

CONCLUSIONS

Our review shows that targeting SSD/FSS at an early stage represents a conceptual and practical challenge. Readily accessible interventions addressing transsymptomatic processes of SSD/FSS development and consolidation are highly needed. Future studies are needed to evaluate individuals with diverse symptoms, examine symptom history thoroughly, use placebo controls, and report outcomes completely to determine the efficacy of early psychological interventions for SSD/FSS.PROSPERO Registration:CRD42020140122.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): III. Emotional dysfunction superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a quantitative nosological system that addresses shortcomings of traditional mental disorder diagnoses, including arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, substantial heterogeneity within disorders, and diagnostic unreliability over time and across clinicians. This paper reviews evidence on the validity and utility of the internalizing and somatoform spectra of HiTOP, which together provide support for an emotional dysfunction superspectrum. These spectra are composed of homogeneous symptom and maladaptive trait dimensions currently subsumed within multiple diagnostic classes, including depressive, anxiety, trauma-related, eating, bipolar, and somatic symptom disorders, as well as sexual dysfunction and aspects of personality disorders. Dimensions falling within the emotional dysfunction superspectrum are broadly linked to individual differences in negative affect/neuroticism. Extensive evidence establishes that dimensions falling within the superspectrum share genetic diatheses, environmental risk factors, cognitive and affective difficulties, neural substrates and biomarkers, childhood temperamental antecedents, and treatment response. The structure of these validators mirrors the quantitative structure of the superspectrum, with some correlates more specific to internalizing or somatoform conditions, and others common to both, thereby underlining the hierarchical structure of the domain. Compared to traditional diagnoses, the internalizing and somatoform spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and greater clinical applicability. Validated measures are currently available to implement the HiTOP system in practice, which can make diagnostic classification more useful, both in research and in the clinic.

Validation of the Chinese version bodily distress syndrome checklist in Chinese out-patients of general hospitals

OBJECTIVE

The 25-item Bodily Distress Syndromes (BDS) checklist was developed to assess BDS symptoms with high validity and reliability. The aim of this study was to reveal the psychometric properties of the Chinese version of the BDS checklist in Chinese outpatients of general hospitals.

METHOD

A cross-sectional study was carried out in nine Chinese general hospitals, consisting of three different medicine settings: biomedicine, traditional medicine, and psychosomatic medicine. The 25-item BDS checklist was translated into the Chinese version and conducted on outpatients from all nine centers. We performed validity and reliability analyses, including test-retest reliability, construct validity, and internal consistency reliability, on the collected checklist data. The convergent validity of the BDS checklist was analyzed with Pearson's Coefficient vs. Patient Health Questionnaire-15 (PHQ-15). The discriminant validity of the BDS checklist was analyzed with Pearson's Coefficient vs. Patient Health Questionnaire-9 (PHQ-9), General Anxiety Disorder-7 (GAD-7) and Whiteley-8 (WI-8).

RESULTS

A total of 699 patients were included in this study. The test-retest reliability, construct validity, and internal consistency reliability of the Chinese version of the BDS were satisfactory in our study. Factor analyses identified five distinct determining factors: cardiopulmonary, gastric, intestinal, musculoskeletal, and general symptoms. Pearson's coefficients were found to be high in both discriminant validity and convergent validity analyses.

CONCLUSION

The results provide empirical support for the Chinese version of the BDS checklist in patients in general hospitals. The Chinese version of the BDS checklist is potentially valuable for case finding in both clinical practice and research in Chinese.

Insulin Resistance Is Associated with Multiple Chemical Sensitivity in a Danish Population-Based Study-DanFunD

Multiple chemical sensitivity (MCS) is a multisystem syndrome, and limited knowledge of its pathophysiology exists. Based on the population-based Danish cohort DanFunD, this study investigated metabolic health in people with MCS compared to individuals who did not have MCS. From 9656 cohort participants aged 18–76 years old, 1.95% were categorized as MCS individuals with comorbid functional somatic disorders (MCS +FSD, n = 188), and 1.13% were categorized as MCS without functional somatic disorders (MCS ÷FSD, n = 109). MCS was characterized based on three criteria: the experience of symptoms upon exposure to common odors and airborne chemicals, symptoms related the central nervous systems and others organ symptoms, and significant impact on every day, social, and occupational life. The remaining study population without MCS or any other functional somatic disorders were regarded as controls. We used adjusted multiple linear regression with link-function to evaluate the associations between lipid and glucose metabolism markers and MCS. We also tested the odds ratio of metabolic syndrome in MCS. Results did not point to statistically significant associations between lipid biomarkers or metabolic syndrome and both MCS groups compared to the controls. We found that MCS individuals may be more insulin resistant and that MCS ÷ FSD may have an impaired glucose metabolism when compared to controls.

Targeting the Gut Microbiota to Relieve the Symptoms of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a common, chronic, functional disorder with a large impact on world population. Its pathophysiology is not completely revealed; however, it is certain that dysregulation of the bidirectional communications between the central nervous system (CNS) and the gut leads to motility disturbances, visceral hypersensitivity, and altered CNS processing characterized by differences in brain structure, connectivity and functional responsiveness. Emerging evidence suggests that gut microbiota exerts a marked influence on the host during health and disease. Gut microbiome disturbances can be also important for development of IBS symptoms and its modulation efficiently contributes to the therapy. In this work, we review the current knowledge about the IBS therapy, the role of gut microbiota in pathogenesis of IBS, and we discuss that its targeting may have significant impact on the effectiveness of IBS therapy.

"I'm So Tired": Fatigue as a Persistent Physical Symptom among Working People Experiencing Exhaustion Disorder

Fatigue is widespread in the population, particularly among working people. Exhaustion disorder (ED), a clinical manifestation of burnout, is common, but, after treatment, about one-third still experience fatigue and other physical symptoms. We propose that in some instances, fatigue as a persistent physical symptom (PPS) might be a more appropriate formulation of ED patients' fatigue problems, and we suggest that ED patients who meet fatigue PPS criteria will differ from other ED patients in terms of psychological distress, non-fatigue PPSs and functional impairment. Questionnaires were sent to 10,956 members of a trade union of which 2479 (22.6%) responded. Of 1090 participants who met criteria for ED, 106 (9.7%) met criteria for fatigue as a PPS. Participants who met fatigue PPS criteria scored on average higher on measures of depression, anxiety and functional impairment and were more likely to have clinically significant scores. Moreover, they had 27 times higher odds of meeting other PPS subtypes and reported more non-fatigue PPS subtypes, suggesting a more complex health problem. Specific evidence-based interventions are available for both ED and PPSs, and therefore, it is crucial to accurately formulate the fatigue problem reported by patients to provide appropriate treatment.

Assessment of functional somatic disorders in epidemiological research: Self-report questionnaires versus diagnostic interviews

OBJECTIVE

Self-reported symptom questionnaires are often used for identifying individuals with functional somatic disorders (FSD) in epidemiological research. Studies on their validity in establishing clinically valid cases are, however, lacking. We aimed to compare and dissect the processes of identifying participants with FSD with symptom questionnaires and FSD diagnoses established by diagnostic interviews.

METHODS

Individuals from the adult Danish population (n = 1590) filled in symptom questionnaires and participated in a diagnostic research interview, performed over telephone by trained family physicians. The two methods were described and compared in different steps: 1) Agreement on presence of symptoms, 2) agreement after FSD symptom pattern criteria had been applied, and 3) agreement on final FSD diagnoses.

RESULTS

Agreement on symptom presence was high (>82%). Using FSD symptom pattern criteria, the two methods agreed in 30-62% of cases within each category. Discrepancies were mainly due to participants fulfilling symptom patterns in the interview but not in the questionnaires. Agreement between final FSD questionnaire cases and final FSD interview diagnoses was moderate (>68%) with lower FSD prevalence in the interview (26.2% vs 44.5%). Discrepancies were largely explained by the interviewers assessing the symptom patterns to be caused by an alternative physical or mental condition.

CONCLUSION

Prevalence of final FSD diagnoses were markedly lower in the diagnostic interview compared to self-reported questionnaires cases; mainly because of the clinical evaluation of symptom attribution and impairment. Symptom questionnaires may be valuable as screening tools and as trans-diagnostic comparison while diagnostic interviews are necessary in establishing clinically significant FSD diagnoses.

British Society of Gastroenterology guidelines on the management of irritable bowel syndrome

Irritable bowel syndrome (IBS) remains one of the most common gastrointestinal disorders seen by clinicians in both primary and secondary care. Since publication of the last British Society of Gastroenterology (BSG) guideline in 2007, substantial advances have been made in understanding its complex pathophysiology, resulting in its re-classification as a disorder of gut-brain interaction, rather than a functional gastrointestinal disorder. Moreover, there has been a considerable amount of new evidence published concerning the diagnosis, investigation and management of IBS. The primary aim of this guideline, commissioned by the BSG, is to review and summarise the current evidence to inform and guide clinical practice, by providing a practical framework for evidence-based management of patients. One of the strengths of this guideline is that the recommendations for treatment are based on evidence derived from a comprehensive search of the medical literature, which was used to inform an update of a series of trial-based and network meta-analyses assessing the efficacy of dietary, pharmacological and psychological therapies in treating IBS. Specific recommendations have been made according to the Grading of Recommendations Assessment, Development and Evaluation system, summarising both the strength of the recommendations and the overall quality of evidence. Finally, this guideline identifies novel treatments that are in development, as well as highlighting areas of unmet need for future research.

Three different approaches to delimitation of functional somatic disorders: DanFunD

OBJECTIVE

The Danish Study of Functional Disorders (DanFunD) approaches functional somatic disorders (FSD) with three delimitations: Five functional somatic syndromes (FSS), Bodily Distress Syndrome (BDS), and eight data-driven symptom profiles (SP). This paper presents each delimitation and discusses optimal approaches for further original research into FSD epidemiology.

METHODS

A total of 9656 adults from the general Danish population participated in this cross-sectional study. Case assignment of the three FSD delimitations was based on self-reported symptom questionnaires. Overlap of FSS, BDS, and SP and their association with poor self-perceived health were calculated as descriptive statistics and shown with Venn diagrams. Difference in self-perceived health between participants with severe FSD were compared with participants with no FSD and calculated as risk ratios with generalized linear models with binomial family and log link.

RESULTS

We found pronounced overlaps between any FSS, BDS, and the SP with multiple symptoms as well as for multi-organ BDS and the SP with all symptoms. Symptoms and syndromes related to clusters of musculoskeletal and general symptoms contributed particularly to poor health as did multi-organ BDS and categories of SP with multiple symptoms.

CONCLUSION

Each of the three delimitations has its strengths and weaknesses, and with this study, we offer a contribution to a more valid delimitation of FSD. Future research within DanFunD and other epidemiological studies may benefit from using more than just one delimitation for capturing the diverse nature of the FSD.

Are there subgroups of chronic fatigue syndrome? An exploratory cluster analysis of biological markers

Background

Chronic fatigue syndrome (CFS) is defined according to subjective symptoms only, and several conflicting case definition exist. Previous research has discovered certain biological alterations. The aim of the present study was to explore possible subgroups based on biological markers within a widely defined cohort of adolescent CFS patients and investigate to what extent eventual subgroups are associated with other variables.

Methods

The Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL) has previously performed detailed investigation of immunological, autonomic, neuroendocrine, cognitive and sensory processing functions in an adolescent group of CFS patients recruited according to wide diagnostic criteria. In the present study, hierarchical cluster analyses (Ward’s method) were performed using representative variables from all these domains. Associations between clusters and constitutional factors (including candidate genetic markers), diagnostic criteria, subjective symptoms and prognosis were explored by standard statistical methods.

Results

A total of 116 patients (26.7% males, mean age 15.4 years) were included. The final cluster analyses revealed six clusters labelled pain tolerant & good cognitions, restored HPA dynamics, orthostatic intolerance, low-grade inflammation, pain intolerant & poor cognitions, and high vagal (parasympathetic) activity, respectively. There was substantial overlap between clusters. The pain intolerant & poor cognitions-cluster was associated with low functional abilities and quality of life, and adherence to the Canada 2003 diagnostic criteria for CFS. No other statistically significant cluster associations were discovered.

Conclusion

Within a widely defined cohort of adolescent CFS patients, clusters could be delineated, but no distinct subgroups could be identified. Associations between clusters and constitutional factors, subjective symptoms and prognosis were scarce. These results question the clinical usefulness of searching for CFS subgroups, as well as the validity of the most “narrow” CFS diagnostic criteria.

Trial registration: Clinical Trials NCT01040429

The BDS checklist as measure of illness severity: a cross-sectional cohort study in the Danish general population, primary care and specialised setting

OBJECTIVE

The bodily distress syndrome (BDS) checklist has proven to be useful in the diagnostic categorisation and as screening tool for functional somatic disorders (FSD). This study aims to investigate whether the BDS checklist total sum score (0-100) can be used as a measure of physical symptom burden and FSD illness severity.

DESIGN

Cross-sectional.

SETTING

Danish general population, primary care and specialised clinical setting.

PARTICIPANTS

A general population cohort (n=9656), a primary care cohort (n=2480) and a cohort of patients with multiorgan BDS from specialised clinical setting (n=492).

OUTCOME MEASURES

All data were self-reported. Physical symptoms were measured with the 25-item BDS checklist. Overall self-perceived health was measured with one item from the 36-item Short-Form Health Survey (SF-36). Physical functioning was measured with an aggregate score of four items from the SF-36/SF-12 scales 'physical functioning', 'bodily pain' and 'vitality'. Emotional distress was measured with the mental distress subscale (SCL-8) from the Danish version of the Hopkins Symptom Checklist-90. Illness worry was measured with the six-item Whiteley Index.

RESULTS

For all cohorts, bifactor models established that despite some multidimensionality the total sum score of the BDS checklist adequately reflected physical symptom burden and illness severity. The BDS checklist had acceptable convergent validity with measures of overall health (r=0.25-0.58), physical functioning (r=0.22-0.58), emotional distress (r=0.47-0.62) and illness worry (r=0.36-0.55). Acceptability was good with a low number of missing responses to items (<3%). Internal consistency was high (α ≥0.879). BDS score means varied and reflected symptom burden across cohorts (13.03-46.15). We provide normative data for the Danish general population.

CONCLUSIONS

The BDS checklist total sum score can be used as a measure of symptom burden and FSD illness severity across settings. These findings establish the usefulness of the BDS checklist in clinics and in research, both as a diagnostic screening tool and as an instrument to assess illness severity.

Irritable bowel syndrome

Irritable bowel syndrome is a functional gastrointestinal disorder with symptoms including abdominal pain associated with a change in stool form or frequency. The condition affects between 5% and 10% of otherwise healthy individuals at any one point in time and, in most people, runs a relapsing and remitting course. The best described risk factor is acute enteric infection, but irritable bowel syndrome is also more common in people with psychological comorbidity and in young adult women than in the rest of the general population. The pathophysiology of irritable bowel syndrome is incompletely understood, but it is well established that there is disordered communication between the gut and the brain, leading to motility disturbances, visceral hypersensitivity, and altered CNS processing. Other less reproducible mechanisms might include genetic associations, alterations in gastrointestinal microbiota, and disturbances in mucosal and immune function. In most people, diagnosis can be made on the basis of clinical history with limited and judicious use of investigations, unless alarm symptoms such as weight loss or rectal bleeding are present, or there is a family history of inflammatory bowel disease or coeliac disease. Once the diagnosis is made, an empathetic approach is key and can improve quality of life and symptoms, and reduce health-care expenditure. The mainstays of treatment include patient education about the condition, dietary changes, soluble fibre, and antispasmodic drugs. Other treatments tend to be reserved for people with severe symptoms and include central neuromodulators, intestinal secretagogues, drugs acting on opioid or 5-HT receptors, or minimally absorbed antibiotics (all of which are selected according to predominant bowel habit), as well as psychological therapies. Increased understanding of the pathophysiology of irritable bowel syndrome in the past 10 years has led to a healthy pipeline of novel drugs in development.

Prevalence and overlap of somatic symptom disorder, bodily distress syndrome and fibromyalgia syndrome in the German general population: A cross sectional study

OBJECTIVE

To study the prevalence and clinical characteristics of Somatic Symptom Disorder (SSD), Bodily Distress Syndrome (BDS) and fibromyalgia syndrome (FMS) and their overlap in the general German population.

METHODS

A cross-sectional nationally representative population survey was performed. 2531 participants (mean age 48.8 ± 17.85 years, 53.3% women) completed the Somatic Symptom Scale SSS-8, the Bodily Distress Syndrome (BDS) 25 checklist, the Whiteley Index 7 (WI-7), the self-administered comorbidity questionnaire and the Michigan Body Map. Case definitions of SSD, BDS and FMS were assigned using established criteria.

RESULTS

4.5% of participants met the criteria of SSD (SSS - 8 at least one item "bothered very much" and WI- 7 total score ≥ 1). 9.6% met the criteria of single-organ BDS and 1.3% of multi-organ BDS. Prevalence of FMS according to 2016 criteria was 3.4%. 82.3% of FMS cases met any BDS criteria.28.1% of FMS cases satisfied SSD criteria. 28.8% of any BDS cases met the criteria of SSD. 75.1% of SSD cases met the criteria of any BDS. FMS cases reported the highest amount of somatic and psychological symptom burden and health anxieties. There were no differences in age and gender between any BDS and SSD cases. SSD cases reported worse general health and more fibromyalgia-related variables than any BDS cases.

CONCLUSIONS

In the general population, there is a substantial overlap between FMS and BDS, but not of FMS and SSD, and not of SSD and any BDS. Case definitions of the three disorders partially captured different groups in the general population.

Validation of the German version of the Bodily Distress Syndrome 25 checklist in a representative German population sample

OBJECTIVE

The Bodily Distress Syndrome 25 (BDS 25) checklist is a self-report instrument that can be used for case finding of a BDS in both clinical practice and research. We assessed the reliability and the internal and external validity of the German version of the BDS 25 in a sample of the general German population.

METHODS

The psychometric properties of the BDS 25 German were examined in a representative cross-sectional German population survey which included 2386 persons aged ≥14 years. Validation instruments included the Somatic Symptom Scale 8, the Giessen Subjective Complaints List 8 and the Patient Health Questionnaire 4. Participants were asked if they had been diagnosed with fibromyalgia or irritable bowel syndrome by a physician in the past.

RESULTS

The acceptance was high. Only 81 (2.3%) single items were not answered. Internal consistency was sufficiently high for all four subscales and the total score (α > 0.800). Exploratory and confirmatory factor analysis revealed clear evidence for a four-factorial structure with cardiopulmonary, gastrointestinal, musculoskeletal and general symptoms. Moderate to high correlations with other measures of somatic and psychological symptom burden were found. In latent class analysis, the model featuring three classes with no, moderate and severe BDS symptoms evinced the best model fit. Participants with self-reported fibromyalgia and irritable bowel syndrome were mainly found in the moderate and severe BDS group.

CONCLUSIONS

The BDS 25 German has excellent psychometric properties to screen for BDS in the general population.

Irritable bowel, chronic widespread pain, chronic fatigue and related syndromes are prevalent and highly overlapping in the general population: DanFunD

Prevalence of functional somatic syndromes (FSS) in the general population varies with observed overlap between syndromes. However, studies including a range of FSS are sparse. We investigated prevalence and characteristics of various FSS and the unifying diagnostic construct bodily distress syndrome (BDS), and identified mutual overlap of the FSS and their overlap with BDS. We included a stratified subsample of 1590 adults from a randomly selected Danish general population sample (n = 7493). Telephonic diagnostic interviews performed by three trained physicians were used to identify individuals with FSS and BDS. Prevalence of overall FSS was 9.3%; 3.8% for irritable bowel, 2.2% for chronic widespread pain, 6.1% for chronic fatigue, 1.5% for whiplash associated disorders, and 0.9% for multiple chemical sensitivity. Prevalence of BDS was 10.7% where 2.0% had the multi-organ type. FSS were highly overlapping with low likelihood of having a “pure” type. Diagnostic agreement of FSS and BDS was 92.0%. Multi-syndromatic FSS and multi-organ BDS were associated with female sex, poor health, physical limitations, and comorbidity. FSS are highly prevalent and overlapping, and multi-syndromatic cases are most affected. BDS captured the majority of FSS and may improve clinical management, making the distinction between multi- and mono-syndromatic patients easier.