A step towards a new delimitation of functional somatic syndromes: A latent class analysis of symptoms in a population-based cohort study

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.

Somatic burden in Russia during the COVID-19 pandemic

Somatic burden has become one of the most common psychological reactions to the COVID-19 pandemic worldwide. This study examined the prevalence of somatic burden, latent profiles, and associated factors of somatic symptoms during the pandemic in a large sample of Russians. We used cross-sectional data from 10,205 Russians collected during October-December, 2021. Prevalence of somatic burden was assessed with the Somatic Symptom Scale-8. Latent profiles of somatic burden were identified using latent profile analysis. Multinomial logistic regression was used to examine demographic, socioeconomic, and psychological associated factors of somatic burden. Over one-third (37%) of the Russians reported being somatised. We selected the three-latent profile solution with high somatic burden profile (16%), medium somatic burden profile (37%), and low somatic burden profile (47%). The associated factors of greater somatic burden were female gender, lower education, history of COVID-19 disease, refusing vaccination against SARS-CoV-2 infection, poorer self-rated health, greater fear of COVID-19 pandemic, and living in regions with higher excess mortality. Overall, this study contributes to knowledge about the prevalence, latent profiles, and associated factors of somatic burden during the COVID-19 pandemic. It can be useful to researchers in psychosomatic medicine and practitioners in the health care system.

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.

Multidisciplinary approach to functional somatic syndromes: study protocol for a population-based prospective cohort study

INTRODUCTION

Isfahan functional disorders (ISFUN) cohort study aims to describe the interplay of genetic and environmental factors in shaping the characteristics of functional somatic syndromes (FSS). This study is primarily intended to investigate the epidemiology, risk factors, course and prognosis of FSSs in a sample of adult Iranian population. The other aim is to develop a new delimitation of FSSs based on an integrated multidisciplinary approach comprising of phenotypic and multiomics data.

METHODS AND ANALYSIS

ISFUN is a population-based prospective cohort study designed to follow a population of randomly selected seemingly healthy adults (18-65 years) through annual visits during a 4-year observation period. Structured questionnaires are used for data collection and clinical assessment of the participants. Questionnaire-based diagnosis of FSSs are validated in a medical interview. Human DNA genotyping, microbial amplicon sequencing and urine analysis is under progress for genomics, microbiota and metabolomics profiling, respectively. Enrolment began in September 2017, and study completion is expected in 2022. A total number of 1943 participants were initially recruited.

ETHICS AND DISSEMINATION

Ethical approval for data collection was granted by the National Research Ethics Committee of the Iranian Ministry of Health and Medical Education and the Research Ethics Committee of Isfahan University of Medical Sciences (IR.MUI.REC.1395.1.149). Following the description of the study procedure, we obtained written informed consent from all study participants. Study findings will be disseminated through peer-reviewed publications and presentations at scientific meetings.

Four clinical profiles of adult outpatients with somatic Symptom Disorders and Related Disorders (SSRD). A latent class analysis

OBJECTIVE

To obtain more insight into the patterns of co-occurring symptoms, biomarkers and predictors in Somatic Symptom Disorders and Related Disorders (SSRD) and to identify subgroups with profiles that might allow for personalised treatment.

METHODS

Cross-sectional study design with Latent class analysis (LCA) to determine different subgroups in a cohort of 239 outpatients with SSRD in 3 steps: 1) building a latent class model; 2) assigning subjects to the latent classes that suited them best based on their posterior probability; 3) investigating the associations between these classes and personal characteristics such as age, gender, somatic comorbidity and general health perception.

RESULTS

Four classes with clinically relevant profiles were found. One with trauma plus elevated inflammation biomarkers, high somatic symptom levels, pain and comorbid depression and anxiety. One with pain plus elevated biomarkers, depression and anxiety. One with low IL-6 and hsCRP, mostly linked to Illness Anxiety. And one with high pain and high elevated biomarkers, but less probability of other factors, that occurred mostly in men. General health perception was lower in classes with elevated inflammation biomarkers.

CONCLUSIONS

The findings of this first study exploring latent classes in an SSRD sample corroborate the current DSM-5 SSD subclassification for pain and Illness Anxiety Disorder. There is scope to extend the current DSM-5 classification with a subclassification of SSD with trauma, and a subclassification with elevated IL6 or hsCRP, as relevant for developing new personalised treatments addressing trauma or SLI in SSRD. Further research is needed to explore this.

Conditioned pain modulation and pain sensitivity in functional somatic disorders: The DanFunD study

Background

Disrupted pain regulation has been proposed as a component in functional somatic disorders (FSD). The objective of this study was to examine a general population sample, encompassing three delimitations of FSD while assessing pain sensitivity and conditioning pain modulation (CPM).

Methods

Pressure pain thresholds (PPTs) at the tibialis and trapezius muscles were recorded at baseline. During cold pressor stimulation of the hand, the tibialis PPTs were re‐assessed and the difference from baseline measures defined the CPM effect. Participants (n = 2,198, 53% females) were randomly selected from the adult Danish population. FSD was established by self‐reported symptom questionnaires.

Results

With a few exceptions, only weak associations were seen between PPTs and CPM in cases with FSD (p > .1). A high PPT was associated with lower odds of having multi‐organ bodily distress syndrome (OR^{PPT trapezius}: 0.66, 95% CI: 0.49–0.88, p = .005), with the symptom profile characterized by all symptoms (OR^{PPT trapezius}: 0.72, 95% CI: 0.58–0.90, p = .003 and OR^{PPT tibialis}: 0.75, 95% CI: 0.62–0.91, p = .004), and with multiple chemical sensitivity (OR^{PPT trapezius}: 0.81, 95% CI: 0.67–0.97, p = .022). High CPM was associated with high odds of having irritable bowel (OR^{CPM relative}: 1.22, 95% CI: 1.04–1.43, p = .013 and OR^{CPM absolute} = 2.66, 95% CI: 1.07–6.45, p = .033).

Conclusion

However, only PPT measured over the trapezius muscle were still significant after correction for multiple testing for the symptom profile characterized by all symptoms. Findings from this study do not support altered pain regulation in questionnaire‐based FSD which is in contrast with the existing presumption. Further epidemiological studies in this field are needed.

Significance

Disrupted pain regulation as measured by abnormal pain thresholds has been hypothesized as a central mechanism in Functional Somatic Disorders (FSD). The hypothesis has been raised in clinical setting where patients presented subjective and objective features of hypersensitivity. The present population‐based study does not support this notion. This points to the importance of further studies into the underlying pathophysiology mechanisms of FSD.

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.

Disability pension among persons with chronic disease: Differential impact of a Danish policy reform

BACKGROUND

In 2013, Denmark implemented a reform that tightened the criteria for disability pension, expanded a subsidized job scheme ('flexi-job') and introduced a new vocational rehabilitation scheme. The overall aim of the reform was to keep more persons attached to the labour market. This study investigates the impact of the reform among persons with chronic disease and whether this impact differed across groups defined by labour market affiliation and chronic disease type.

METHODS

The study was conducted as a register-based, nationwide cohort study. The study population included 480 809 persons between 40 and 64 years of age, who suffered from at least one of six chronic diseases. Hazard ratios (HR) and 95% confidence intervals (CI) of being awarded disability pension or flexi-job in the 5 years after vs. the 5 years prior to the reform were estimated.

RESULTS

Overall, the probability of being awarded disability pension was halved after the reform (HR = 0.49, CI: 0.47-0.50). The impact was largest for persons receiving sickness absence benefits (HR = 0.31, CI: 0.24-0.39) and for persons with functional disorders (HR = 0.38, CI: 0.32-0.44). Also, the impact was larger for persons working in manual jobs than for persons working in non-manual jobs. The probability of being awarded a flexi-job was decreased by one-fourth (HR = 0.76, CI: 0.74-0.79) with the largest impact for high-skilled persons working in non-manual jobs.

CONCLUSION

Access to disability pension and flexi-job decreased after the reform. This impact varied according to labour market affiliation and chronic disease type.

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.

Psychosomatic symptoms questionnaire (PSQ-39): a psychometric study among general population of Iranian adults

BACKGROUND

Psychosomatic symptoms, characterized by physical-bodily complaints not fully explained by organic reasons, are highly prevalent. The present study aimed to culturally adapt and evaluate the psychometric properties of Psychosomatic Symptoms Questionnaire 39-item version (PSQ-39) among Iranian general adult population.

METHODS

This study included 996 Persian-speaking people, living in Isfahan, Iran. The translation of the PSQ-39 was performed using the forward-backward method. Test-retest reliability was evaluated through Intraclass correlation (ICC) coefficient and internal consistency by using Cronbach's α. Construct validity was investigated by using both exploratory (EFA) and confirmatory (CFA) factor analysis. Short Form Health Survey (SF-36) was used to assess divergent validity. Known-group validity was also assessed.

RESULTS

The Persian version of the PSQ-39 showed excellent test-retest reliability in all domains (ICCs: 0.95-0.99). The computed Cronbach's alpha coefficients for domains of PSQ-39 were in the range good to excellent. The PSQ-39 showed good known-group validity and differentiated patients from the general population (Area under the curve [AUC] of 0.78 (95% CI: 0.73, 0.84). Construct validity evaluated by EFA led to extraction of seven factors (Cardiorespiratory, musculoskeletal, psychological, gastrointestinal, general, body balance and Globus), and the CFA confirmed the adequacy of extracted factors by EFA (CFI = 0.91, TLI = 0.90, PCFI = 0.77, PNFI = 0.71, CMIN = 1413.18 (df = 654), CMIN/DF = 2.16, and RMSEA = 0.06). Significant negative correlations between all domains of PSQ and SF-36 revealed an acceptable divergent Validity.

CONCLUSIONS

The Persian version of the PSQ-39 is a reliable and valid questionnaire with applicability in a broad range of Persian language populations for assessing common psychosomatic symptoms in research as well as in clinical practice.

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.

Extragastrointestinal Symptoms and Sensory Responses During Breath Tests Distinguish Patients With Functional Gastrointestinal Disorders

INTRODUCTION

Patients with functional gastrointestinal disorders (FGIDs) are classified based on their gastrointestinal (GI) symptoms, without considering their frequent extra-GI symptoms. This study defined subgroups of patients using both GI and extra-GI symptoms and examined underlying mechanisms with fructose and lactose breath tests.

METHODS

Latent class analysis defined distinct clusters of patients with FGID based on their long-term GI and extra-GI symptoms. Sensory and breath gas responses after fructose and lactose ingestion were compared across symptom clusters to investigate differences in sensory function and fermentation by intestinal microbiota.

RESULTS

Six symptom clusters were identified in 2,083 patients with FGID. Clusters were characterized mainly by GI fermentation-type (cluster 1), allergy-like (cluster 2), intense pain-accentuated GI symptoms (cluster 3), central nervous system (cluster 4), musculoskeletal (cluster 5), and generalized extra-GI (cluster 6) symptoms. In the 68% of patients with complete breath tests, the areas under the curve of GI and central nervous system symptoms after fructose and lactose ingestion differed across the clusters (P < 0.001). The clusters with extensive long-term extra-GI symptoms had greater symptoms after the sugars and were predominantly women, with family or childhood allergy histories. Importantly, the areas under the curves of hydrogen and methane breath concentrations were similar (P > 0.05) across all symptom clusters. Rome III criteria did not distinguish between the symptom clusters.

DISCUSSION

Patients with FGID fall into clusters defined extensively by extra-GI symptoms. Greater extra-GI symptoms are associated with evidence of generalized sensory hypersensitivity to sugar ingestion, unrelated to intestinal gas production. Possible underlying mechanisms include metabolites originating from the intestinal microbiota and somatization.

Increased instruction time and stress-related health problems among school children

While several studies suggest that stress-related mental health problems among school children are related to specific elements of schooling, empirical evidence on this causal relationship is scarce. We examine a German schooling reform that increased weekly instruction time and study its effects on stress-related outpatient diagnoses from the universe of health claims data of the German Social Health Insurance. Exploiting the differential timing in the reform implementation across states, we show that the reform slightly increased stress-related health problems among school children. While increasing instruction time might increase student performance, it might have adverse effects in terms of additional stress.

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.

Multiple physical symptoms and individual characteristics - A cross-sectional study of the general population

OBJECTIVE

Multiple physical symptoms not attributable to known organic disease are common in all medical fields and associated with major personal and social consequences. This study investigated multiple physical symptoms according to the construct of bodily distress syndrome (BDS) and associated individual characteristics in the general adult population.

METHODS

A nationwide, population-based study of 100,000 randomly selected individuals aged 20 years and older, conducted in 2012. A web-based questionnaire formed the basis of the study and was combined with Danish national registry data on socioeconomic factors and medication and healthcare use.

RESULTS

49,706 individuals completed the questionnaire. After exclusion of women indicating pregnancy, respondents reporting chronic disease and respondents over 65 years of age, 23,331 remained for analysis. Of these 23,331 individuals, 15.5% fulfilled the criteria for BDS. BDS positives were more often younger (20-40 years) and female. Self-rated health and self-reported functional capacity were impaired among these individuals. Fulfilling the BDS criteria was significantly associated with current or former smoking, overweight and obesity, low educational level and income, and unemployment. Moreover, individuals with BDS were more often from ethnic minorities and had higher use of healthcare and medication.

CONCLUSION

Multiple physical symptoms, as captured by the concept of BDS, are common in the general adult population, especially among younger women. Fulfilling the BDS criteria is associated with substantial negative impact on self-perceived health and socioeconomic parameters. Fulfilling BDS criteria is positively associated with health risk behaviors (smoking, overweight and obesity) and higher use of healthcare and medication.

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

OBJECTIVES

Bodily distress syndrome (BDS) has been shown to encompass a range of functional somatic syndromes (FSS) such as irritable bowel syndrome (IBS), fibromyalgia (FM), and chronic fatigue syndrome (CFS) in clinical samples. This study aimed to explore symptom clusters and test classification of individuals with illness similar to the BDS criteria in a general population sample.

METHODS

A stratified subsample of 1590 individuals from the DanFunD part two cohort was included. Symptoms were assessed with the Research Interview for Functional somatic Disorders, performed by trained physicians. In 44 symptoms pooled from criteria of IBS, FM, CFS, and BDS, symptom clusters were explored with explorative factor analysis. Confirmation of symptom clusters of BDS in the previously described 25- and 30-item BDS checklists was performed with confirmatory factor analysis. Classification of individuals into illness groups was investigated with latent class analysis.

RESULTS

Four symptom clusters (cardiopulmonary, gastrointestinal, musculoskeletal, general symptoms/fatigue) corresponding to the BDS subtypes and their corresponding FSS were identified and confirmed. A three-class model including 25 BDS items had the best fit for dividing participants into classes of illness: One class with low probability, one class with medium probability, and one class with high probability of having ≥4 symptoms in all symptom clusters.

CONCLUSION

The BDS concept was confirmed in the general population and constitutes a promising approach for improved FSS classification. It is highly clinical relevant being the only diagnostic construct defining the complex multi-organ type.

Persistent dentoalveolar pain disorder: A putative intraoral chronic overlapping pain condition

Chronic overlapping pain conditions (COPCs) are conditions that share several clinical characteristics and symptomatology, are usually considered idiopathic in nature, and are frequently comorbid. Currently, there are no established inclusion criteria to determine which conditions should be included under this umbrella term despite different systems proposed. Persistent dentoalveolar pain disorder (PDAP), also referred to as atypical odontalgia and thought to be a component of persistent idiopathic facial pain, is a chronic pain condition that manifests as a persistent tooth pain or pain over a dentoalveolar site formerly occupied by a tooth in the absence of detectable pathology during clinical or radiological examination. PDAP is considered idiopathic in nature, and its pathophysiological mechanisms are not fully understood. Our objective was to investigate whether PDAP fits the conceptual paradigm of COPC given its characteristics and commonalities with other COPC, based on published literature identified through a scoping review. We found that PDAP fits 16 out of 18 common characteristics among COPCs, and based on this finding, we discuss the implications of PDAP being considered a COPC.

Prevalence of functional somatic syndromes and bodily distress syndrome in the Danish population: the DanFunD study

Aims: Little is known about the prevalence and characteristics of functional somatic syndromes (FSS) such as irritable bowel syndrome (IBS), fibromyalgia (FM), chronic fatigue syndrome (CFS), whiplash associated disorders (WAD), multiple chemical sensitivity (MCS), and bodily distress syndrome (BDS) in the general population when they are investigated simultaneously. Method: This cross-sectional study is based on the Danish Study of Functional Disorders (DanFunD) cohort consisting of 9656 adults from the general population. FSS and BDS were identified by questionnaires and characterized by age, sex, vocational training, physical health and comorbidity with physical and psychiatric disease. Results: In total, 16.3% (95% CI: 15.6–17.1) of the participants fulfilled the criteria for at least one FSS, ranging from 1.7% for WAD to 8.6% for CFS, and 16.1% (95% CI: 15.4–16.9) fulfilled the criteria for BDS. Cases had a high risk of poor self-perceived health, limitations in daily activities, and a high psychiatric comorbidity, all increasing with the number of syndromes in each individual. However, the associations differed across the various FSS. Mutual overlaps of IBS, FM and CFS were greater than could be expected by chance. Conclusions: FSS and BDS are prevalent in the adult Danish population, and cases have high risk of poor self-perceived health, limitation in daily activities, and psychiatric comorbidity. These associations were particularly strong for cases with multiple FSS and multi-organ BDS.

Clinical Characteristics of Disability in Patients with Indoor Air-Related Environmental Intolerance

Background

Chronic nonspecific symptoms attributed to indoor nonindustrial work environments are common and may cause disability, but the medical nature of this disability is unclear. The aim was to medically characterize the disability manifested by chronic, recurrent symptoms and restrictions to work participation attributed to low-level indoor pollutants at workplace and whether the condition shares features with idiopathic environmental intolerance.

Methods

We investigated 12 patients with indoor air–related work disability. The examinations included somatic, psychological, and psychiatric evaluations as well as investigations of the autonomic nervous system, cortisol measurements, lung function, and allergy tests. We evaluated well-being, health, disability, insomnia, pain, anxiety, depression, and burnout via questionnaires.

Results

The mean symptom history was 10.5 years; for disabling symptoms, 2.7 years. Eleven patients reported reactions triggered mainly by indoor molds, one by fragrances only. Ten reported sensitivity to odorous chemicals, and three, electric devices. Nearly all had co-occurrent somatic and psychiatric diagnoses and signs of pain, insomnia, burnout, and/or elevated sympathetic responses. Avoiding certain environments had led to restrictions in several life areas. On self-assessment scales, disability showed higher severity and anxiety showed lower severity than in physician assessments.

Conclusion

No medical cause was found to explain the disability. Findings support that the condition is a form of idiopathic environmental intolerance and belongs to functional somatic syndromes. Instead of endless avoidance, rehabilitation approaches of functional somatic syndromes are applicable.

Third Wave Treatments for Functional Somatic Syndromes and Health Anxiety Across the Age Span: A Narrative Review

Functional disorders (FD) are present across the age span and are commonly encountered in somatic health care. Psychological therapies have proven effective, but mostly the effects are slight to moderate. The advent of third wave cognitive behavioural therapies launched an opportunity to potentially improve treatments for FD.

A narrative review of the literature on the application of mindfulness-based therapies (MBT) and Acceptance &amp; Commitment Therapy (ACT) in children and adult populations with FD.

There were very few and mainly preliminary feasibility studies in children and adolescents. For adults there were relatively few trials of moderate to high methodological quality. Ten MBT randomised trials and 15 ACT randomised trials of which 8 were internet-delivered were identified for more detailed descriptive analysis. There was no evidence to suggest higher effects of third wave treatments as compared to CBT. For MBT, there seemed to be minor effects comparable to active control conditions. A few interventions combining second and third wave techniques found larger effects, but differences in outcomes, formats and dosage hamper comparability.

Third wave treatments are getting established in treatment delivery and may contribute to existing treatments for FD. Future developments could further integrate second and third wave treatments across the age span. Elements unambiguously targeting specific illness beliefs and exposure should be included. The benefit of actively engaging close relatives in the treatment not only among younger age groups but also in adults, as well as the effect of more multimodal treatment programmes including active rehabilitation, needs to be further explored.

The methodological quality of third wave interventions for FD should be improved, especially in younger age groups.

The effect of ACT interventions may be comparable to CBT in adults with FD.

The evidence for third wave interventions in young people with FD is still very limited.

Newer studies combining second and third wave treatments show some promise.

Agreement on, and for child populations further development of, core outcomes, could help determine effect across studies.