Integrated care model for patients with functional somatic symptom disorder - a co-produced stakeholder exploration with recommendations for best practice.

BACKGROUND: Functional somatic symptoms (FFS) and bodily distress disorders are highly prevalent across all medical settings. Services for these patients are dispersed across the health care system with minimal conceptual and operational integration, and patients do not currently access therapeutic offers in significant numbers due to a mismatch between their and professionals' understanding of the nature of the symptoms. New service models are urgently needed to address patients' needs and to align with advances in aetiological evidence and diagnostic classification systems to overcome the body-mind dichotomy. METHOD: A panel of clinical experts from different clinical services involved in providing aspects of health care for patients with functional symptoms reviewed the current care provision. This review and the results from a focus group exploration of patients with lived experience of functional symptoms were explored by the multidisciplinary expert group, and the conclusions are summarised as recommendations for best practice. RESULTS: The mapping exercise and multidisciplinary expert consultation revealed five themes for service improvement and pathway development: time/access, communication, barrier-free care, choice and governance. Service users identified four meta-themes for best practice recommendations: focus on healthcare professional communication and listening skills as well as professional attributes and knowledge base to help patients being both believed and understood in order to accept their condition; systemic and care pathway issues such as stronger emphasis on primary care as the first point of contact for patients, resources to reduce the length of the patient journey from initial assessment to diagnosis and treatment. CONCLUSION: We propose a novel, integrated care pathway for patients with 'functional somatic disorder', which delivers care according to and working with patients' explanatory beliefs. The therapeutic model should operate based upon an understanding of the embodied nature of patient's complaints and provide flexible access points to the care pathway.

[Psychocorporal approach to functional somatic disorders]. / Prise en charge psychocorporelle des troubles somatiques fonctionnels.

Functional somatic disorders (FSD) are common conditions that result in a significant deterioration of the quality of life. Their origin is multifactorial and poorly understood, and their management is often inadequately defined. Medications typically show limited effectiveness, while mind-body approaches play a central role, guided by three key principles: establishing an empathetic, respectful, and sincere doctor-patient relationship; promoting regular and gradual physical activity; and implementing cognitive behavioral therapy (CBT). Special attention must be devoted to establishing a trustworthy relationship between the physician and the patient. Recognizing the reality and severity of symptoms and providing a positive diagnosis as well as an explanatory model to account for them rationally are fundamental aspects of patient management. Cognitive and behavioral maintenance factors should be investigated and constitute therapeutic targets. Cognitive factors include focused attention on body functioning and catastrophizing. Patients frequently display avoidance behaviors, particularly in relation to physical exertion, and it is crucial to motivate them to reintroduce gradual physical activity customized to their abilities. This approach has demonstrated efficacy in improving fatigue, pain, and the physical and mental quality of life for patients with FSD. Among psychotherapeutic approaches, the benefit of CBT is well-established. The combination of gradual physical activity and CBT appears to be complementary. Other mind-body approaches such as mindfulness meditation might help although their level of evidence is weaker. Given the prevalence of FSD in the general population, it seems necessary for all physicians to be trained in managing this condition.

Somatic symptom disorder symptoms in individuals at risk for heart failure: A cluster analysis with cross-sectional data from a population-based cohort study.

OBJECTIVE: Identifying whether experienced symptom burden in individuals with medical predisposition indicates somatic symptom disorder (SSD) is challenging, given the high overlap in the phenomenology of symptoms within this group. This study aimed to enhance understanding SSD in individuals at risk for heart failure. SUBJECTS AND METHODS: Cross-sectional data from the Hamburg City Health Study was analyzed including randomly selected individuals from the general population of Hamburg, Germany recruited from February 2016 to November 2018. SSD symptoms assessed with the Somatic Symptom Scale-8 and the Somatic Symptom Disorder-12 scale were categorized by applying cluster analysis including 412 individuals having at least 5% risk for heart failure-related hospitalization within the next ten years. Clusters were compared for biomedical and psychological factors using ANOVA and chi-square tests. Linear regressions, adjusting for sociodemographic, biomedical, and psychological factors, explored associations between clusters with general practitioner visits and quality of life. RESULTS: Three clusters emerged: none (n = 215; 43% female), moderate (n = 151; 48% female), and severe (n = 46; 54% female) SSD symptom burden. The SSS-8 mean sum scores were 3.4 (SD = 2.7) for no, 6.4 (SD = 3.4) for moderate, and 12.4 (SD = 3.7) for severe SSD symptom burden. The SSD-12 mean sum scores were 3.1 (SD = 2.6) for no, 12.2 (SD = 4.2) for moderate, and 23.5 (SD = 6.7) for severe SSD symptom burden. Higher SSD symptom burden correlated with biomedical factors (having diabetes: p = .005 and dyspnea: p ≤ .001) and increased psychological burden (depression severity: p ≤ .001; anxiety severity: p ≤ .001), irrespective of heart failure risk (p = .202). Increased SSD symptoms were associated with more general practitioner visits (ß = 0.172; p = .002) and decreased physical quality of life (ß = -0.417; p ≤ .001). CONCLUSION: Biomedical factors appear relevant in characterizing individuals at risk for heart failure, while psychological factors affect SSD symptom experience. Understanding SSD symptom diversity and addressing subgroup needs could prove beneficial.

Phenomenology of Somatization in Immigrants: An Idealtypical Approach.

INTRODUCTION: Somatization in immigrants is frequent but standard studies do not differentiate between various forms of somatization. In this qualitative study, we used an idealtypical approach with the aim of phenomenologically differentiating between different forms of somatization in immigrants. METHODS: The clinical description of the ideal types was based on seven levels: medical examination; description of somatization symptoms; the patients' own interpretation of their somatic experience; concomitant psychopathological phenomena; genetic understanding; clinician's interpretation; and course and treatment. RESULTS: Five different ideal typologies of patients emerged: anxious hypochondriasis, somatization with cultural features playing a pathogenetic role, culturally shaped somatization (through pathoplastic effects), somatization as part of adjustment reactions due to migratory living difficulties, and somatization as post-traumatic reaction. CONCLUSION: These differences are useful to highlight the complex interrelationship between socioeconomic, migratory, cultural, and value factors in the construction of somatization among immigrants. Implications for research methodology, nosology, clinical management, and organization of medical facilities are also discussed.

Medical and psychiatric comorbidities, somatic and cognitive symptoms, injuries and medical procedure history in patients with functional seizures from a public and a private hospital.

PURPOSE: Patients with functional seizures (FS), otherwise known as psychogenic non-epileptic seizures (PNES), from different socioeconomic backgrounds may differ, however, this remains a gap in current literature. Comorbidities can play both a precipitating and a perpetuating role in FS and are important in the planning of individual treatment for this condition. With this study, we aimed to describe and compare the reported medical and psychiatric comorbidities, injuries, somatic and cognitive symptoms, and medical procedures among patients with FS from a private and a public epilepsy monitoring unit (EMU) in Cape Town, South Africa. METHODS: This is a retrospective case-control study. We collected data on the comorbidity and medical procedure histories, as well as symptoms and clinical signs reported by patients with video-electroencephalographically (video-EEG) confirmed FS without comorbid epilepsy. We used digital patient records starting with the earliest available digital record for each hospital until the year 2022. RESULTS: A total of 305 patients from a private hospital and 67 patients from a public hospital were included in the study (N = 372). Public hospital patients had higher odds of reporting intellectual disability (aOR=15.58, 95% CI [1.80, 134.95]), circulatory system disease (aOR=2.63, 95% CI [1.02, 6.78]) and gait disturbance (aOR=8.52, 95% CI [1.96, 37.08]) compared to patients with FS attending the private hospital. They did, however, have fewer odds of reporting a history of an infectious or parasitic disease (aOR=0.31, 95% CI [0.11, 0.87]), respiratory system disease (aOR=0.23, 95% CI [0.06, 0.82]), or medical procedures in the past (aOR=0.32, 95% CI [0.16, 0.63]). CONCLUSION: The study presents prevalence and comparative data on the medical profiles of patients with FS from different socioeconomic backgrounds which may inform future considerations in FS diagnosis and treatment.

An integrated mental health video consultations model for patients with somatic symptom disorder in primary care: The randomized VISION pilot trial.

OBJECTIVE: Symptoms of somatic symptom disorder (SSD) are one of the most common reasons for consultations in primary care. However, specialized psychological services are mostly unavailable. This pilot trial aimed to determine the feasibility, acceptability, and safety of the integrated mental health video consultations VISION model for patients with SSD in primary care. METHODS: We conducted a parallel group, randomized controlled pilot trial involving fifty-one patients with SSD from ten primary care practices in Germany, who we randomized to the VISION model or enhanced treatment-as-usual (eTAU). The VISION model comprised five video consultations which featured diagnostic clarification, psychoeducation (acknowledging and legitimizing of symptoms), and brief psychological therapy. eTAU included training primary care practice teams on the DSM-5 concept of SSD and on current guideline recommendations for its treatment in primary care. We assessed feasibility as the primary outcome at 6-months, measuring efficiency of recruitment, intervention acceptability, and safety. RESULTS: Recruitment was efficient reflected in an overall recruitment yield (number randomized per number screened) of 55% (51/92) and a consent rate (number randomized per number eligible) of 94% (51/54). Acceptability of the intervention was high with 98% (123/125) of the video consultations conducted as planned. No serious adverse events were reported in either group. CONCLUSION: An integrated mental health video consultations VISION model for patients with SSD presenting to primary care is feasible, acceptable, and safe. Potential clinical effectiveness of the model should be evaluated in confirmatory trial implementing the multifaceted approach tailored to the individual patient with SSD directly into primary care practice. TRIAL REGISTRATION: The trial protocol was registered at German Clinical Trials Register (number: DRKS00026075, https://www.drks.de).

Changes in interoceptive accuracy related to emotional interference in somatic symptom disorder.

OBJECTIVE: The somatic symptom disorder (SSD) is characterized by one or more distressing or disabling somatic symptoms accompanied by an excessive amount of time, energy and emotion related to the symptoms. These manifestations of SSD have been linked to alterations in perception and appraisal of bodily signals. We hypothesized that SSD patients would exhibit changes in interoceptive accuracy (IA), particularly when emotional processing is involved. METHODS: Twenty-three patients with SSD and 20 healthy controls were recruited. IA was assessed using the heartbeat perception task. The task was performed in the absence of stimuli as well as in the presence of emotional interference, i.e., photographs of faces with an emotional expression. IA were examined for correlation with measures related to their somatic symptoms, including resting-state heart rate variability (HRV). RESULTS: There was no significant difference in the absolute values of IA between patients with SSD and healthy controls, regardless of the condition. However, the degree of difference in IA without emotional interference and with neutral facial interference was greater in patients with SSD than in healthy controls (p = 0.039). The IA of patients with SSD also showed a significant correlation with low-frequency HRV (p = 0.004) and high-frequency HRV (p = 0.007). CONCLUSION: SSD patients showed more significant changes in IA when neutral facial interference was given. These results suggest that bodily awareness is more affected by emotionally ambiguous stimuli in SSD patients than in healthy controls.

Association of categorical diagnoses and psychopathologies with quality of life in patients with depression, anxiety, and somatic symptoms: A cross-sectional study.

OBJECTIVE: Major depressive disorder (MDD), anxiety disorders, and somatic symptom disorder (SSD) are associated with quality of life (QoL) reduction. This cross-sectional study investigated the relationship between these conditions as categorical diagnoses and related psychopathologies with QoL, recognizing their frequent overlap. METHODS: We recruited a total of 403 clinical patients and healthy individuals, administering diagnostic interviews based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. QoL and psychopathologies were assessed using the WHO Quality of Life-BREF (WHOQOL-BREF) and several self-administered questionnaires, respectively. Multiple linear regression analyses examined the associations between psychiatric diagnoses, psychopathologies, and QoL. RESULTS: SSD and MDD were independently associated with impaired global (ß = -0.318 and - 0.287) and all QoL domains (ß = -0.307, -0.150, -0.125, and - 0.133, in physical, psychological, social, and environmental domains respectively for SSD; ß = -0.278, -0.344, -0.275, and - 0.268 for MDD). The Beck Depression Inventory-II score showed pervasive associations with QoL (ß = -0.390, -0.408, -0.685, -0.463, and - 0.420, in global, physical, psychological, social, and environmental domains). The Patient Health Questionnaire-15 and Health Anxiety Questionnaire scores were associated with global (ß = -0.168 and - 0.181) and physical (ß = -0.293 and - 0.121) QoL domain, while the Cognitions About Body and Health Questionnaire score was only associated with environmental QoL domain (ß = -0.157). CONCLUSION: SSD and MDD were independently associated with QoL impairment. Depressive symptoms were associated with all QoL domains, whereas somatic symptom burden and health anxiety primarily affected the physical QoL domain. Clinicians should consider concomitant psychopathologies when managing patients with depression, anxiety, or somatic symptoms.

Psychological flexibility in somatic symptom and related disorders: A case control study.

A key diagnostic criterion of Somatic Symptom and related Disorders (SSD) comprises significant distress and excessive time-and-energy consuming thoughts, feelings, and behavior pertaining to somatic symptoms. This diagnostic criterion is lacking in central sensitivity syndromes (CSS), such as fibromyalgia, irritable bowel syndrome, and chronic fatigue syndrome. This strong emphasis on disturbed psychological processing of somatic symptoms, suggests that psychological flexibility is low in SDD. Psychological flexibility is defined as the ability to approach difficult or challenging internal states (thoughts, emotions, and bodily sensations) in a non-judgmental, mindful way, and being committed to pursue one's values. To clarify the potential significance of psychological flexibility in SSD, we examined its levels in 154 people referred to specialized treatment for SDD, as compared to reference groups from the general population encompassing 597 people with CSS and 1422 people without SSD or CSS (controls). Mean levels of psychological flexibility (adjusted for demographic covariates) were lowest for SSD and highest for controls (F = 154.5, p < 0.001, pη2 = 0.13). Percentages of people with low psychological flexibility (<0.8 SD below the mean of controls) were: SSD 74%, CSS 42%, controls 21%. In SSD, higher psychological flexibility was associated with better mental health (ß = 0.56, p < 0.001), but interaction analysis rejected that psychological flexibility preserved health when having more severe somatic symptoms (ß ≤ 0.08, p ≥ 0.10). The results indicate that lower psychological flexibility is a prevalent problem in SSD that is associated with lower mental health. This suggests that it is worthwhile to take account of psychological flexibility in SSD in screening, monitoring, and therapy.

Applying hypnotic associative - dissociative techniques in psychotherapy for psychosomatic symptoms.

Patients experiencing psychosomatic symptoms frequently have difficulty obtaining correct treatment. They are often reluctant to partially attribute their symptoms to psychological factors and, as a result, delay referrals to mental health professionals. Furthermore, the dropout rate from therapy is high and relapses are common. Hypnosis is a complex psycho-physiological phenomenon. Hence, hypnotic psychotherapy may play an important role in managing and treating psychosomatic symptoms and disorders that involve both the mind and body. In the current study, we propose a clinically oriented, four-phase, hypnotic approach, the hypnotic associative-dissociative approach (HADA), which may be useful in encouraging more patients with psychosomatic problems to engage in psychotherapy, thereby achieving effective long-term effects.

Reliability and Validity of the Korean Version of the Somatic Symptom Disorder-B Criteria Scale in a Clinical Population.

OBJECTIVE: This study aimed to develop and validate the Korean version of the Somatic Symptom Disorder-B Criteria Scale (SSD-12) in outpatients at a psychiatric clinic and assess its diagnostic accuracy. METHODS: A total of 207 patients completed SSD-12. For the diagnostic accuracy of SSD-12, the somatic symptom disorder (SSD) section of the structured clinical interview for DSM-5 disorders-research version (SCID-5-RV) was used. The SSD-12 construct and concurrent validity were assessed by examining the correlations with Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-9 (PHQ-9), PHQ-15, 5-level EQ-5D version (EQ-5D-5L), and World Health Organization Quality of Life Brief Version (WHOQOL-BREF). RESULTS: The SSD-12 had excellent internal consistency (Cronbach α=0.90). Confirmatory factor analysis revealed good fit indices for a general factor model (comparative fit index [CFI]=0.92, Tucker-Lewis index [TLI]=0.88, root mean square error of approximation [RMSEA]=0.10; 95% confidence interval [CI], 0.08-0.11) and a three-factor model (CFI=0.94, TLI=0.91, RMSEA=0.08; 95% CI, 0.07-0.10). The total SSD-12 score was significantly correlated with anxiety (GAD-7: r=0.53, p<0.001), depression (PHQ-9: r=0.52, p<0.001), physical symptom burden (PHQ-15: r=0.36, p<0.001), and quality of life (EQ-5D-5L: r=-0.40, p<0.001; WHOQOL-BREF: r=-0.51, p<0.001). SSD-12 demonstrated good accuracy (area under the curve=0.75, standard error=0.04; 95% CI, 0.68-0.82) with an optimal cut-off of 29. CONCLUSION: The Korean SSD-12 demonstrates reliability and validity for diagnosing SSD in clinical setting.

Psychobehavioral B-Criteria of Somatic Symptom Disorder Are Associated with Somatic Symptom Reporting in a Large Sample of Psychosomatic Outpatients.

Introduction: Somatic symptom disorder (SSD) as introduced by the DSM-5 is characterized by chronic somatic symptoms not fully explained by underlying pathology and accompanied by psychological factors, the diagnostic B-criteria. These cognitive, affective, and behavioral disturbances are related to increased attention to somatic symptoms. However, there is a lack of empirical evidence regarding the association between the B-criteria and high symptom reporting in clinical settings. Methods: This 12-year retrospective, cross-sectional, observational study examined 6,491 patients from a German psychosomatic outpatient center. The somatoform subscale of HEALTH-49 was used to evaluate somatic symptom reporting. Excessive health concerns and other potential criteria associated with symptom reporting were determined using the ICD-10-Symptom Rating and other HEALTH-49 subscales. Results: Regression analysis revealed that the established B-criteria for SSD were the strongest factors associated with somatic symptom reporting, with a standardized beta-coefficient of ß = 0.31 (R2 = 0.428, df = 24, F = 187.886). Other psychobehavioral factors were clearly less associated with somatic symptom reporting, such as depressive symptoms with ß = 0.15 and impaired activity and participation with ß = 0.12. Sociodemographic factors, such as age (ß = 0.16) and gender (ß = 0.12), were also independently associated with somatic symptom reporting. Conclusion: This study provides evidence for the concept of SSD related to specific B-criteria associated with somatic symptom reporting, based on a large patient sample. These results point to an important role of psychological symptomatology in patients with somatic symptoms. The findings also suggest that additional factors contribute to the reporting of somatic symptoms. Our results may inform future diagnostic criteria for SSD.

This scientific study examines the association between psychobehavioral factors and somatic symptom reporting in a large sample of psychosomatic outpatients. We investigated the association of established and possible additional psychobehavioral criteria for somatic symptom disorder (SSD) as defined in the DSM-V. The study included 6,491 patients from a psychosomatic outpatient center over a 12-year period. The participants completed self-report questionnaires to assess somatic symptom reporting and psychobehavioral factors. The results showed that the B-criteria of SSD were associated with somatic symptom reporting, indicating the validity of these criteria in clinical practice. Other psychobehavioral factors, such as depressive symptoms and impaired activity and participation, as well as sociodemographic factors such as age and gender were also associated with somatic symptom reporting but to a much lesser extent. This study has limitations, including its retrospective and cross-sectional design, reliance on self-report measures, and the need for further research using longitudinal data and clinician-rated assessments to complement self-report data. However, our research highlights the importance of psychological symptomatology in individuals who report somatic symptoms. These findings may inform future diagnostic criteria and treatment approaches for individuals with SSD and improve treatment and patient outcomes.

[Health anxiety: Another epidemic to prepare for]. / L'anxiété centrée sur la santé : une autre épidémie à laquelle il faut se préparer.

Health anxiety (HA) is a frequent problem (up to 20% of consultants in the context of secondary care) responsible for decreased well-being, disability, somatic and psychiatric complications, which contributes to high healthcare expenditures at the population level. It is likely, if not definitely established, that the prevalence of ACS is increasing, and this can partly be explained by the growing medicalization of society in general, the appetite of Media for health issues, and the uncontrolled use of the Internet (which can lead certain vulnerable subjects to cyberchondria). The pandemic of COVID-19 could have contributed to it, at least by the significant increase in the overall level of psychological distress in the population it has caused, although this has not formally been demonstrated to date. The diagnosis of ACS is easy, as soon as its assessment is considered as a mandatory part of any medical consultation. Certain intuitive attitudes of doctors, such as reassurance, prove to be iatrogenic for the patient with HA. The management of HA can be facilitated by an acculturation of physicians to cognitive conceptions of anxiety in general and HA in particular. HA is effectively treatable by certain psychotherapy and in the first place cognitive and behavioral therapies (CBT), but the availability of trained therapists and accessible at a lower cost is sorely lacking, particularly in France.

Autistic Traits and Somatic Symptom Disorders: What Is the Link?

Alterations in sensory processing, a key component of autism spectrum disorder (ASD), have recently attracted increasing attention as they result in peculiar responses to sensory stimuli, possibly representing a risk factor for the development of somatic symptom disorder (SSD). Contextually, other features also associated with ASD, such as alexithymia, camouflaging and altered verbal, and non-verbal communication, have been suggested to represent risk factors for the occurrence and worsening of somatic symptomatology. The aim of this work was to review the available literature about the association between SSD and the autism spectrum. The results highlighted not only a higher prevalence of autistic features in patients suffering from SSD and a higher prevalence of reported somatic symptomatology in subjects with ASD but also how ASD subjects with co-occurrent somatic symptoms exhibit more severe autism-linked symptomatology. From the paper reviewed also emerged many shared features between the two conditions, such as alexithymia, altered sensitivity to sensory stimuli, cognitive inflexibility, intolerance of uncertainty, and an increased risk of experiencing stressful life events, which may provide an explanation for the correlation reported. Even though studies on the topic are still scant, the evidence reported suggests the importance of further assessing the correlation between the two disorders.

Psychological risk factors of somatic symptom disorder: A systematic review and meta-analysis of cross-sectional and longitudinal studies.

OBJECTIVE: Current diagnostic concepts of somatic symptom disorder (SSD) in DSM-5 and bodily distress disorder (BDD) in ICD-11 require certain psychological criteria, but researchers have called for further specification. Therefore, in a first step, this systematic review and meta-analysis aimed to summarize the current evidence on psychological factors associated with SSD/BDD and/or disorder-relevant clinical outcomes such as symptom severity and impairment. METHODS: Psychological factors were systematically searched using Pubmed, Cochrane Library and Psycinfo via EBSCO. Studies providing original data in English or German, after 2009 were included. Cross-sectional, cohort and case-control studies investigating at least one psychological factor in individuals with SSD/BDD in the context of disorder-relevant outcomes were included. RESULTS: Forty-three eligible studies (n = 3760 patients) in SSD (none in BDD) provided data on at least one psychological factor, 37 in case-control format, 10 cross-sectional and 5 longitudinal. Meta-analyses of the case-control studies found patients with SSD to be more impaired by depression (SMD = 1.80), anxiety (SMD = 1.55), health anxiety (SMD = 1.31) and alexithymia (SMD = 1.39), compared to healthy controls. Longitudinal results are scarce, mixed, and require refining, individual studies suggest self-concept of bodily weakness, anxiety and depression to be predictive for persistent SSD and physical functioning. CONCLUSION: This review provides a detailed overview of the current evidence of psychological factors in relation to SSD/BDD. Future studies on SSD and BDD should include under-studied psychological factors, such as negative affect, fear avoidance, or emotion regulation. More longitudinal studies are needed to assess the predictive value of these factors.

Affective dysfunction mediates the link between neuroimmune markers and the default mode network functional connectivity, and the somatic symptoms in somatic symptom disorder.

OBJECTIVE: Somatic symptom disorder (SSD) is characterized by physical symptoms and associated functional impairments that are often comorbid with depression and anxiety disorders. In this study, we explored relationships between affective symptoms and the functional connectivity of the default mode network (DMN) in SSD patients, as well as the impact of peripheral inflammation. We employed mediation analyses to investigate the potential pathways between these factors. METHODS: We recruited a total of 119 individuals (74 unmedicated SSD patients and 45 healthy controls), who were subjected to comprehensive psychiatric and clinical evaluations, blood tests, and resting-state functional magnetic resonance imaging scanning. We assessed neuroimmune markers (interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), tryptophan, serotonin, and 5-hydroxyindoleacetic acid (5-HIAA)), clinical indicators of somatic symptoms, depression, anxiety, anger, alexithymia, and functional connectivity (FC) within the DMN regions. Data were analyzed using correlation and mediation analysis, with a focus on exploring potential relations between clinical symptoms, blood indices, and DMN FCs. RESULTS: Patients with SSD had higher clinical scores as well as IL-6 and TNF-α levels compared with those in the control group (P < 0.05). The SSD group exhibited lower FC strength between the left inferior parietal lobule and left prefrontal cortex (Pfalse discovery rate (FDR) < 0.05). Exploratory correlation analysis revealed that somatic symptom scores were positively correlated with affective symptom scores, negatively correlated with the FC strength between the intra prefrontal cortex regions, and correlated with levels of IL-6, TNF- α, and tryptophan (uncorrected P < 0.01). Mediation analysis showed that levels of anxiety and trait anger significantly mediated the relations between DMN FC strength and somatic symptoms. In addition, the DMN FC mediated the level of trait anger with respect to somatic symptoms (all PFDR < 0.05). The levels of depression and trait anger exhibited significant mediating effects as suppressors of the relations between the level of 5-HIAA and somatic symptom score (all PFDR < 0.05). Further, the level of 5-HIAA had a mediating effect as a suppressor on the relation between DMN FC and state anger. Meanwhile, the levels of hs-CRP and IL-6 had full mediating effects as suppressors when explaining the relations of DMN FC strengths with the level of depression (all PFDR < 0.05). The patterns of valid mediation pathways were different in the control group. CONCLUSIONS: Affective symptoms may indirectly mediate the associations between DMN connectivity, somatic symptoms, and neuroimmune markers. Inflammatory markers may also mediate the impact of DMN connectivity on affective symptoms. These results emphasize the importance of affective dysregulation in understanding the mechanisms of SSD and have potential implications for the development of tailored therapeutic approaches for SSD patients with affective symptoms. Furthermore, in SSD research using DMN FC or neuroimmune markers, considering and incorporating such mediating effects of affective symptoms suggests the possibility of more accurate prediction and explanation.