xml: <clinical_study>
    <!-- This xml conforms to an XML Schema at:
      https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
    <required_header>
      <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
      <link_text>Link to the current ClinicalTrials.gov record.</link_text>
      <url>https://clinicaltrials.gov/ct2/show/NCT06006715</url>
    </required_header>
    <id_info>
      <org_study_id>DanFunD Psychiatric disorders</org_study_id>
      <nct_id>NCT06006715</nct_id>
    </id_info>
    <brief_title>Psychiatric Disorders and Functional Somatic Disorders</brief_title>
    <official_title>Psychiatric Disorders as Risk Factor for Functional Somatic Disorders. DanFunD - a Population-based Study</official_title>
    <sponsors>
      <lead_sponsor>
        <agency>Aarhus University Hospital</agency>
        <agency_class>Other</agency_class>
      </lead_sponsor>
      <collaborator>
        <agency>Center for Clinical Research and Prevention</agency>
        <agency_class>Other</agency_class>
      </collaborator>
    </sponsors>
    <source>University of Aarhus</source>
    <oversight_info>
      <has_dmc>No</has_dmc>
      <is_fda_regulated_drug>No</is_fda_regulated_drug>
      <is_fda_regulated_device>No</is_fda_regulated_device>
    </oversight_info>
    <brief_summary>
      <textblock>
        The objectives of this study are: Firstly, to investigate the association between psychiatric&#xD;
        disorders and functional somatic disorder (FSD). Secondly, to investigate whether psychiatric&#xD;
        disorders are risk factors for newly developed (incident) FSD after a 5-year follow-up&#xD;
        period.&#xD;
      </textblock>
    </brief_summary>
    <detailed_description>
      <textblock>
        Functional somatic disorder (FSD) is a common condition characterized by a persistent pattern&#xD;
        of impairing physical symptoms. Our knowledge about what causes the development and&#xD;
        perpetuating of these disorders is still sparse, however, it is well accepted that they have&#xD;
        a multifactorial aetiology, comprising both biological, psychological, and social factors.&#xD;
  &#xD;
        The relationship between FSD and other conditions have been investigated in different&#xD;
        manners: A study in patients with severe FSD have shown an increased number of other physical&#xD;
        diagnoses compared to healthy controls. A general population-based study has shown FSD to be&#xD;
        associated with other self-reported physical diseases, depression, and anxiety. Further,&#xD;
        psychopathology has shown to predict irritable bowel syndrome and fibromyalgia, while&#xD;
        irritable bowel syndrome has shown to predict common mental disorders (5). However, for some&#xD;
        diagnoses, e.g. whiplash associated disorders, the relationship with psychiatric disorders is&#xD;
        more inconsistent.&#xD;
  &#xD;
        The previous research may carry some limitations: Clinical studies into highly selected&#xD;
        patient samples may carry risk of selection bias, and most population-based studies have used&#xD;
        self-report for establishing FSD diagnoses and psychiatric diagnoses which may bring risk of&#xD;
        misclassification. Hence, more studies with a sound methodology into these aspects are&#xD;
        needed.&#xD;
  &#xD;
        The proposed longitudinal study includes data from two investigations of the same cohort from&#xD;
        the general Danish population. Both validated symptom questionnaires and diagnostic&#xD;
        interviews will be used for the establishment of FSD diagnoses and psychiatric discharge&#xD;
        diagnoses and prescription medication will be obtained from the comprehensive Danish Central&#xD;
        Registries.&#xD;
  &#xD;
        Objective&#xD;
  &#xD;
        The objective of this study is twofold:&#xD;
  &#xD;
          1. To investigate the association between psychiatric disorders and FSD&#xD;
  &#xD;
          2. To investigate whether psychiatric disorders are risk factors for development of&#xD;
             incident FSD in a 5-year follow-up period&#xD;
  &#xD;
        Hypotheses:&#xD;
  &#xD;
          1. Psychiatric disorders (across all included diagnoses) are positively associated with FSD&#xD;
  &#xD;
          2. Anxiety disorder, depression, bipolar disorder, personality disorder, and stress-related&#xD;
             disorder as individual diagnoses are positively associated with FSD&#xD;
  &#xD;
          3. Psychiatric disorders (across all included diagnoses) are associated with newly&#xD;
             developed (incident) FSD (FSD negative at baseline and FSD positive at follow-up)&#xD;
  &#xD;
          4. Anxiety disorder, depression, bipolar disorder, personality disorder, and stress-related&#xD;
             disorder as individual diagnoses are associated with newly developed (incident) FSD (FSD&#xD;
             negative at baseline and FSD positive at follow-up)&#xD;
  &#xD;
        Data from the DanFunD (Danish Study of Functional Disorders) baseline and 5-year follow-up&#xD;
        investigations will be included. The baseline cohort is a random sample selected through the&#xD;
        National Civil Registration system among people living in 10 municipalities in the western&#xD;
        part of greater Copenhagen, Denmark, aged 18 to 76 years. The baseline cohort constitutes&#xD;
        data from self-reported validated symptom questionnaires and diagnostic interviews. The&#xD;
        follow-up cohort consists of participants all born in Denmark, between 24 and 84 years of&#xD;
        age. The follow-up cohort also constitutes data from self-reported validated symptom&#xD;
        questionnaires and diagnostic interviews.&#xD;
  &#xD;
        Psychiatric diagnoses will be obtained from the Danish National Patient Registry according to&#xD;
        the International Classification of Diseases, 10th Revision (ICD-10). In order to obtain&#xD;
        cases with more 'mild' psychiatric disorders that do not require hospital admission,&#xD;
        prescriptions for relevant pharmacological treatment of these disorders will be obtained from&#xD;
        the Danish National Prescription Registry.&#xD;
  &#xD;
        Primary outcome (dependent variables):&#xD;
  &#xD;
        Participants with FSD will be defined as follows:&#xD;
  &#xD;
          -  Participants with FSD operationalised by the Bodily Distress Syndrome single- and&#xD;
             multi-organ type will be defined with both questionnaires and diagnostic interviews&#xD;
  &#xD;
          -  Participants with a functional somatic syndrome, i.e. irritable bowel, chronic&#xD;
             widespread pain, and chronic fatigue will be defined with questionnaires&#xD;
  &#xD;
        Primary explanatory/independent variables:&#xD;
  &#xD;
        Psychiatric disorders will be identified by means of&#xD;
  &#xD;
          1. inpatient and outpatient hospital diagnoses (both primary and secondary diagnoses) coded&#xD;
             in the Danish National Patient Registry according to ICD-10, and&#xD;
  &#xD;
          2. prescriptions for relevant pharmacological treatment of these disorders from the Danish&#xD;
             National Prescription Registry.&#xD;
  &#xD;
        The time frame will be 10 years before the DanFunD baseline investigation and the 5-year&#xD;
        period between the baseline and follow-up investigation.&#xD;
  &#xD;
        All analyses will be performed using STATA version 17.0. Descriptive tables will be performed&#xD;
        with number and percentages of individuals with psychiatric diagnoses (overall psychiatric&#xD;
        diagnosis and specific categories: anxiety disorder, depression, bipolar disorder,&#xD;
        personality disorder, and stress-related disorder) and use of prescription medication across&#xD;
        FSD diagnoses and controls.&#xD;
  &#xD;
        Hypothesis 1:&#xD;
  &#xD;
        Relevant regression models with FSD obtained at baseline as primary outcome (baseline FSD&#xD;
        positive = 1, baseline FSD negative = 0) and a dichotomous variable constituting overall&#xD;
        psychiatric diagnoses and/or prescription medicine (at least one: yes = 1, no = 0) received&#xD;
        within a period of 10 years before baseline as primary explanatory variable will be&#xD;
        performed.&#xD;
  &#xD;
        Hypothesis 2:&#xD;
  &#xD;
        Relevant regression models with FSD obtained at baseline as primary outcome (baseline FSD&#xD;
        positive = 1, baseline FSD negative = 0) and a dichotomous variable constituting each&#xD;
        specific diagnosis and prescription medication for the specific diagnoses (anxiety disorder,&#xD;
        depression, bipolar disorder, personality disorder, and stress-related disorder) (yes = 1, no&#xD;
        = 0) received within a period of 10 years before baseline as primary explanatory variable&#xD;
        will be performed.&#xD;
  &#xD;
        As some of the prescription medication may be prescribed for several of the included&#xD;
        diagnoses, a sub analysis will be performed for hypothesis 2, where only the specific&#xD;
        diagnoses will constitute the primary outcome variable, i.e. without prescription medication.&#xD;
  &#xD;
        For the analyses of hypotheses 1 and 2, prevalence odds ratios (POR) with 95% confidence&#xD;
        intervals (CI) will be used as measure of association. A POR &gt; 1 supports the hypotheses.&#xD;
        Depending on number of cases, the analyses will be adjusted for as many of the following&#xD;
        covariates (prioritized order) as possible without over fitting the data: 1. Sex, 2. age, 3.&#xD;
        social status, and 4. severe physical disease (measured with the Charlson comorbidity index).&#xD;
  &#xD;
        Hypothesis 3:&#xD;
  &#xD;
        Relevant regression models with newly developed FSD at follow-up as primary outcome&#xD;
        (follow-up FSD positive = 1, baseline FSD negative = 0) and a dichotomous variable&#xD;
        constituting overall psychiatric diagnoses and/or prescription medicine (at least one: yes =&#xD;
        1, no = 0) received within a period of 10 years before baseline as primary explanatory&#xD;
        variable will be performed.&#xD;
  &#xD;
        Hypothesis 4:&#xD;
  &#xD;
        Relevant regression models with newly developed FSD at follow-up as primary outcome&#xD;
        (follow-up FSD positive = 1, baseline FSD negative = 0) and a dichotomous variable&#xD;
        constituting each specific diagnosis and prescription medication for the specific diagnoses&#xD;
        (anxiety disorder, depression, bipolar disorder, personality disorder, and stress-related&#xD;
        disorder) (yes = 1, no = 0) received within a period of 10 years before baseline as primary&#xD;
        explanatory variable will be performed.&#xD;
  &#xD;
        As some of the prescription medication may be prescribed for several of the included&#xD;
        diagnoses, a sub analysis will be performed for hypothesis 4, where only the specific&#xD;
        diagnoses will constitute the primary outcome variable, i.e. without prescription medication.&#xD;
  &#xD;
        For the analyses of hypotheses 3 and 4, odds ratios (OR) with 95% CI will be used as measure&#xD;
        of association. An OR &gt; 1 supports the hypotheses.&#xD;
  &#xD;
        Depending on number of cases, the analyses will be adjusted for as many of the following&#xD;
        covariates (prioritized order) as possible without over fitting of the data: 1. Sex, 2. age,&#xD;
        3. social status, and 4. severe physical disease (measured with the Charlson comorbidity&#xD;
        index).&#xD;
      </textblock>
    </detailed_description>
    <overall_status>Completed</overall_status>
    <start_date type="Actual">November 10, 2011</start_date>
    <completion_date type="Actual">August 30, 2022</completion_date>
    <primary_completion_date type="Actual">January 4, 2021</primary_completion_date>
    <study_type>Observational</study_type>
    <has_expanded_access>No</has_expanded_access>
    <study_design_info>
      <observational_model>Cohort</observational_model>
      <time_perspective>Prospective</time_perspective>
    </study_design_info>
    <primary_outcome>
      <measure>Questionnaire-defined Functional somatic disorder at baseline</measure>
      <time_frame>At the DanFunD baseline investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with self-reported questionnaires.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Interview-based Functional somatic disorder at baseline</measure>
      <time_frame>Time Frame: At the DanFunD baseline investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with diagnostic interviews.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Questionnaire-defined Functional somatic disorder at 5-year follow-up</measure>
      <time_frame>Time Frame: At the DanFunD 5-year follow-up investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with self-reported questionnaires.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Interview-based Functional somatic disorder at 5-year follow-up</measure>
      <time_frame>Time Frame: At the DanFunD 5-year follow-up investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with diagnostic interviews.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Irritable bowel at baseline</measure>
      <time_frame>Time Frame: At the DanFunD baseline investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria for irritable bowel will be identified with self-reported questionnaires</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Irritable bowel at 5-year follow-up</measure>
      <time_frame>Time Frame: At the DanFunD 5-year follow-up investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria for irritable bowel will be identified with self-reported questionnaires</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Chronic widespread pain at baseline</measure>
      <time_frame>Time Frame: At the DanFunD baseline investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria for chronic widespread pain will be identified with self-reported questionnaires</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Chronic widespread pain at 5-year follow-up</measure>
      <time_frame>Time Frame: At the DanFunD 5-year follow-up investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria for chronic widespread pain will be identified with self-reported questionnaires.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Chronic fatigue at baseline</measure>
      <time_frame>Time Frame: At the DanFunD baseline investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria for chronic fatigue will be identified with self-reported questionnaires.</description>
    </primary_outcome>
    <primary_outcome>
      <measure>Chronic fatigue at 5-year follow-up</measure>
      <time_frame>Time Frame: At the DanFunD 5-year follow-up investigation</time_frame>
      <description>Participants fulfilling the diagnostic criteria for chronic fatigue will be identified with self-reported questionnaires.</description>
    </primary_outcome>
    <other_outcome>
      <measure>Presence of psychiatric disorders (overall): Yes/no</measure>
      <time_frame>Time frame: Given within 10 years before the DanFunD baseline investigation.</time_frame>
      <description>Defined as having at least one of the following psychiatric diagnoses: Alcohol and drug abuse, anxiety disorders, depression and bipolar disorders, developmental and behavioural disorders, eating disorders, schizophrenia spectrum disorders, and stress-related disorders.</description>
    </other_outcome>
    <other_outcome>
      <measure>Presence of anxiety disorders: Yes/no</measure>
      <time_frame>Time frame: Given within 10 years before the DanFunD baseline investigation.</time_frame>
      <description>Defined as having at least one of the ICD-10 codes F40, F41, and F42 or ATC-codes N06A.</description>
    </other_outcome>
    <other_outcome>
      <measure>Presence of depression: Yes/no</measure>
      <time_frame>Time frame: Given within 10 years before the DanFunD baseline investigation.</time_frame>
      <description>Defined as having at least one of the ICD-10 codes F32 and F33 or ATC-codes N06A and N05AN01.</description>
    </other_outcome>
    <other_outcome>
      <measure>Presence of bipolar disorder: Yes/no</measure>
      <time_frame>Time frame: Given within 10 years before the DanFunD baseline investigation.</time_frame>
      <description>Defined as having at least one of the ICD-10 codes F30 and F31 or ATC-codes N06A and N05AN01.</description>
    </other_outcome>
    <other_outcome>
      <measure>Presence of personality disorder: Yes/no</measure>
      <time_frame>Time frame: Given within 10 years before the DanFunD baseline investigation.</time_frame>
      <description>Defined with the ICD-10 code F6.</description>
    </other_outcome>
    <other_outcome>
      <measure>Presence of stress-related disorders: Yes/no</measure>
      <time_frame>Time frame: Given within 10 years before the DanFunD baseline investigation.</time_frame>
      <description>Defined with the ICD-10 code F43.</description>
    </other_outcome>
    <number_of_groups>2</number_of_groups>
    <enrollment type="Actual">7493</enrollment>
    <condition>Irritable Bowel</condition>
    <condition>Fibromyalgia</condition>
    <condition>Chronic Fatigue Syndrome</condition>
    <condition>Bodily Distress Syndrome</condition>
    <condition>Medically Unexplained Syndrome</condition>
    <arm_group>
      <arm_group_label>DanFunD baseline</arm_group_label>
      <description>The baseline cohort (gathered in the years 2012-2015) is a random sample selected through the National Civil Registration system among people living in 10 municipalities in the western part of greater Copenhagen, Denmark, ages 18 to 76 years. The baseline cohort constitutes data from self-reported questionnaires (n=7,493) and diagnostic interviews data (n=1,590).</description>
    </arm_group>
    <arm_group>
      <arm_group_label>DanFunD 5-years follow-up investigation</arm_group_label>
      <description>The follow-up cohort (gathered in the years 2018-2020) consists of participants all born in Denmark, between 24 and 84 years of age. The follow-up cohort constitutes data from self-reported questionnaires (n=4,288) and diagnostic interviews data (n=1,094).</description>
    </arm_group>
    <eligibility>
      <study_pop>
        <textblock>
          A total of 25,368 participants were randomly drawn from the adult general Danish population&#xD;
          by means of the the Danish Civil Registration system.&#xD;
  &#xD;
          The DanFunD baseline cohort comprises a total of 7,493 (29.5% of invited participants) men&#xD;
          and women aged 18-76 years, born in Denmark, and living in the Western part of greater&#xD;
          Copenhagen.&#xD;
  &#xD;
          The follow-up cohort (gathered in the years 2018-2020) consists of participants all born in&#xD;
          Denmark, between 24 and 84 years of age. The follow-up cohort constitutes data from&#xD;
          self-reported questionnaires (n=4,288) and diagnostic interviews data (n=1,094).&#xD;
        </textblock>
      </study_pop>
      <sampling_method>Probability Sample</sampling_method>
      <criteria>
        <textblock>
          Inclusion Criteria:&#xD;
  &#xD;
            -  None&#xD;
  &#xD;
          Exclusion Criteria:&#xD;
  &#xD;
            -  Not born in Denmark&#xD;
  &#xD;
            -  Not being a Danish citizen&#xD;
  &#xD;
            -  Pregnancy&#xD;
        </textblock>
      </criteria>
      <gender>All</gender>
      <minimum_age>18 Years</minimum_age>
      <maximum_age>84 Years</maximum_age>
      <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
    </eligibility>
    <overall_official>
      <last_name>Per Fink, DMSc</last_name>
      <role>Study Chair</role>
      <affiliation>Aarhus University Hospital</affiliation>
    </overall_official>
    <verification_date>August 2023</verification_date>
    <study_first_submitted>August 17, 2023</study_first_submitted>
    <study_first_submitted_qc>August 22, 2023</study_first_submitted_qc>
    <study_first_posted type="Actual">August 23, 2023</study_first_posted>
    <last_update_submitted>September 5, 2023</last_update_submitted>
    <last_update_submitted_qc>September 5, 2023</last_update_submitted_qc>
    <last_update_posted type="Actual">September 8, 2023</last_update_posted>
    <responsible_party>
      <responsible_party_type>Sponsor</responsible_party_type>
    </responsible_party>
    <condition_browse>
      <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
      <mesh_term>Fibromyalgia</mesh_term>
      <mesh_term>Fatigue Syndrome, Chronic</mesh_term>
      <mesh_term>Syndrome</mesh_term>
      <mesh_term>Mental Disorders</mesh_term>
      <mesh_term>Problem Behavior</mesh_term>
      <mesh_term>Somatoform Disorders</mesh_term>
    </condition_browse>
    <patient_data>
      <sharing_ipd>No</sharing_ipd>
      <ipd_description>Restrictions apply to the availability of data according to Danish law, which means that data cannot be made publicly available. A request for collaboration or access to data can be sent to ckff@regionh.dk. An application for data should consist of a short synopsis of the study planned. Please see our website (www. danfund.org) for more information.</ipd_description>
    </patient_data>
    <!-- Results have not yet been posted for this study                                          -->
  </clinical_study>
  
  
text: download date: ClinicalTrials.gov processed this data on September 20, 2023
  link text: Link to the current ClinicalTrials.gov record.
  url: https://clinicaltrials.gov/ct2/show/NCT06006715
  org study id: DanFunD Psychiatric disorders
  nct id: NCT06006715
  lead sponsor: 
  collaborator: 
  has dmc: No
  is fda regulated drug: No
  is fda regulated device: No
  The objectives of this study are: Firstly, to investigate the association between psychiatric
        disorders and functional somatic disorder (FSD). Secondly, to investigate whether psychiatric
        disorders are risk factors for newly developed (incident) FSD after a 5-year follow-up
        period.
  Functional somatic disorder (FSD) is a common condition characterized by a persistent pattern
        of impairing physical symptoms. Our knowledge about what causes the development and
        perpetuating of these disorders is still sparse, however, it is well accepted that they have
        a multifactorial aetiology, comprising both biological, psychological, and social factors.
  
        The relationship between FSD and other conditions have been investigated in different
        manners: A study in patients with severe FSD have shown an increased number of other physical
        diagnoses compared to healthy controls. A general population-based study has shown FSD to be
        associated with other self-reported physical diseases, depression, and anxiety. Further,
        psychopathology has shown to predict irritable bowel syndrome and fibromyalgia, while
        irritable bowel syndrome has shown to predict common mental disorders (5). However, for some
        diagnoses, e.g. whiplash associated disorders, the relationship with psychiatric disorders is
        more inconsistent.
  
        The previous research may carry some limitations: Clinical studies into highly selected
        patient samples may carry risk of selection bias, and most population-based studies have used
        self-report for establishing FSD diagnoses and psychiatric diagnoses which may bring risk of
        misclassification. Hence, more studies with a sound methodology into these aspects are
        needed.
  
        The proposed longitudinal study includes data from two investigations of the same cohort from
        the general Danish population. Both validated symptom questionnaires and diagnostic
        interviews will be used for the establishment of FSD diagnoses and psychiatric discharge
        diagnoses and prescription medication will be obtained from the comprehensive Danish Central
        Registries.
  
        Objective
  
        The objective of this study is twofold:
  
          1. To investigate the association between psychiatric disorders and FSD
  
          2. To investigate whether psychiatric disorders are risk factors for development of
             incident FSD in a 5-year follow-up period
  
        Hypotheses:
  
          1. Psychiatric disorders (across all included diagnoses) are positively associated with FSD
  
          2. Anxiety disorder, depression, bipolar disorder, personality disorder, and stress-related
             disorder as individual diagnoses are positively associated with FSD
  
          3. Psychiatric disorders (across all included diagnoses) are associated with newly
             developed (incident) FSD (FSD negative at baseline and FSD positive at follow-up)
  
          4. Anxiety disorder, depression, bipolar disorder, personality disorder, and stress-related
             disorder as individual diagnoses are associated with newly developed (incident) FSD (FSD
             negative at baseline and FSD positive at follow-up)
  
        Data from the DanFunD (Danish Study of Functional Disorders) baseline and 5-year follow-up
        investigations will be included. The baseline cohort is a random sample selected through the
        National Civil Registration system among people living in 10 municipalities in the western
        part of greater Copenhagen, Denmark, aged 18 to 76 years. The baseline cohort constitutes
        data from self-reported validated symptom questionnaires and diagnostic interviews. The
        follow-up cohort consists of participants all born in Denmark, between 24 and 84 years of
        age. The follow-up cohort also constitutes data from self-reported validated symptom
        questionnaires and diagnostic interviews.
  
        Psychiatric diagnoses will be obtained from the Danish National Patient Registry according to
        the International Classification of Diseases, 10th Revision (ICD-10). In order to obtain
        cases with more 'mild' psychiatric disorders that do not require hospital admission,
        prescriptions for relevant pharmacological treatment of these disorders will be obtained from
        the Danish National Prescription Registry.
  
        Primary outcome (dependent variables):
  
        Participants with FSD will be defined as follows:
  
          -  Participants with FSD operationalised by the Bodily Distress Syndrome single- and
             multi-organ type will be defined with both questionnaires and diagnostic interviews
  
          -  Participants with a functional somatic syndrome, i.e. irritable bowel, chronic
             widespread pain, and chronic fatigue will be defined with questionnaires
  
        Primary explanatory/independent variables:
  
        Psychiatric disorders will be identified by means of
  
          1. inpatient and outpatient hospital diagnoses (both primary and secondary diagnoses) coded
             in the Danish National Patient Registry according to ICD-10, and
  
          2. prescriptions for relevant pharmacological treatment of these disorders from the Danish
             National Prescription Registry.
  
        The time frame will be 10 years before the DanFunD baseline investigation and the 5-year
        period between the baseline and follow-up investigation.
  
        All analyses will be performed using STATA version 17.0. Descriptive tables will be performed
        with number and percentages of individuals with psychiatric diagnoses (overall psychiatric
        diagnosis and specific categories: anxiety disorder, depression, bipolar disorder,
        personality disorder, and stress-related disorder) and use of prescription medication across
        FSD diagnoses and controls.
  
        Hypothesis 1:
  
        Relevant regression models with FSD obtained at baseline as primary outcome (baseline FSD
        positive = 1, baseline FSD negative = 0) and a dichotomous variable constituting overall
        psychiatric diagnoses and/or prescription medicine (at least one: yes = 1, no = 0) received
        within a period of 10 years before baseline as primary explanatory variable will be
        performed.
  
        Hypothesis 2:
  
        Relevant regression models with FSD obtained at baseline as primary outcome (baseline FSD
        positive = 1, baseline FSD negative = 0) and a dichotomous variable constituting each
        specific diagnosis and prescription medication for the specific diagnoses (anxiety disorder,
        depression, bipolar disorder, personality disorder, and stress-related disorder) (yes = 1, no
        = 0) received within a period of 10 years before baseline as primary explanatory variable
        will be performed.
  
        As some of the prescription medication may be prescribed for several of the included
        diagnoses, a sub analysis will be performed for hypothesis 2, where only the specific
        diagnoses will constitute the primary outcome variable, i.e. without prescription medication.
  
        For the analyses of hypotheses 1 and 2, prevalence odds ratios (POR) with 95% confidence
        intervals (CI) will be used as measure of association. A POR > 1 supports the hypotheses.
        Depending on number of cases, the analyses will be adjusted for as many of the following
        covariates (prioritized order) as possible without over fitting the data: 1. Sex, 2. age, 3.
        social status, and 4. severe physical disease (measured with the Charlson comorbidity index).
  
        Hypothesis 3:
  
        Relevant regression models with newly developed FSD at follow-up as primary outcome
        (follow-up FSD positive = 1, baseline FSD negative = 0) and a dichotomous variable
        constituting overall psychiatric diagnoses and/or prescription medicine (at least one: yes =
        1, no = 0) received within a period of 10 years before baseline as primary explanatory
        variable will be performed.
  
        Hypothesis 4:
  
        Relevant regression models with newly developed FSD at follow-up as primary outcome
        (follow-up FSD positive = 1, baseline FSD negative = 0) and a dichotomous variable
        constituting each specific diagnosis and prescription medication for the specific diagnoses
        (anxiety disorder, depression, bipolar disorder, personality disorder, and stress-related
        disorder) (yes = 1, no = 0) received within a period of 10 years before baseline as primary
        explanatory variable will be performed.
  
        As some of the prescription medication may be prescribed for several of the included
        diagnoses, a sub analysis will be performed for hypothesis 4, where only the specific
        diagnoses will constitute the primary outcome variable, i.e. without prescription medication.
  
        For the analyses of hypotheses 3 and 4, odds ratios (OR) with 95% CI will be used as measure
        of association. An OR > 1 supports the hypotheses.
  
        Depending on number of cases, the analyses will be adjusted for as many of the following
        covariates (prioritized order) as possible without over fitting of the data: 1. Sex, 2. age,
        3. social status, and 4. severe physical disease (measured with the Charlson comorbidity
        index).
  observational model: Cohort
  time perspective: Prospective
  measure: Questionnaire-defined Functional somatic disorder at baseline
  time frame: At the DanFunD baseline investigation
  description: Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with self-reported questionnaires.
  measure: Interview-based Functional somatic disorder at baseline
  time frame: Time Frame: At the DanFunD baseline investigation
  description: Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with diagnostic interviews.
  measure: Questionnaire-defined Functional somatic disorder at 5-year follow-up
  time frame: Time Frame: At the DanFunD 5-year follow-up investigation
  description: Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with self-reported questionnaires.
  measure: Interview-based Functional somatic disorder at 5-year follow-up
  time frame: Time Frame: At the DanFunD 5-year follow-up investigation
  description: Participants fulfilling the diagnostic criteria of the unifying diagnostic concept Bodily Distress Syndrome single- and multi-organ type will be defined with diagnostic interviews.
  measure: Irritable bowel at baseline
  time frame: Time Frame: At the DanFunD baseline investigation
  description: Participants fulfilling the diagnostic criteria for irritable bowel will be identified with self-reported questionnaires
  measure: Irritable bowel at 5-year follow-up
  time frame: Time Frame: At the DanFunD 5-year follow-up investigation
  description: Participants fulfilling the diagnostic criteria for irritable bowel will be identified with self-reported questionnaires
  measure: Chronic widespread pain at baseline
  time frame: Time Frame: At the DanFunD baseline investigation
  description: Participants fulfilling the diagnostic criteria for chronic widespread pain will be identified with self-reported questionnaires
  measure: Chronic widespread pain at 5-year follow-up
  time frame: Time Frame: At the DanFunD 5-year follow-up investigation
  description: Participants fulfilling the diagnostic criteria for chronic widespread pain will be identified with self-reported questionnaires.
  measure: Chronic fatigue at baseline
  time frame: Time Frame: At the DanFunD baseline investigation
  description: Participants fulfilling the diagnostic criteria for chronic fatigue will be identified with self-reported questionnaires.
  measure: Chronic fatigue at 5-year follow-up
  time frame: Time Frame: At the DanFunD 5-year follow-up investigation
  description: Participants fulfilling the diagnostic criteria for chronic fatigue will be identified with self-reported questionnaires.
  measure: Presence of psychiatric disorders (overall): Yes/no
  time frame: Time frame: Given within 10 years before the DanFunD baseline investigation.
  description: Defined as having at least one of the following psychiatric diagnoses: Alcohol and drug abuse, anxiety disorders, depression and bipolar disorders, developmental and behavioural disorders, eating disorders, schizophrenia spectrum disorders, and stress-related disorders.
  measure: Presence of anxiety disorders: Yes/no
  time frame: Time frame: Given within 10 years before the DanFunD baseline investigation.
  description: Defined as having at least one of the ICD-10 codes F40, F41, and F42 or ATC-codes N06A.
  measure: Presence of depression: Yes/no
  time frame: Time frame: Given within 10 years before the DanFunD baseline investigation.
  description: Defined as having at least one of the ICD-10 codes F32 and F33 or ATC-codes N06A and N05AN01.
  measure: Presence of bipolar disorder: Yes/no
  time frame: Time frame: Given within 10 years before the DanFunD baseline investigation.
  description: Defined as having at least one of the ICD-10 codes F30 and F31 or ATC-codes N06A and N05AN01.
  measure: Presence of personality disorder: Yes/no
  time frame: Time frame: Given within 10 years before the DanFunD baseline investigation.
  description: Defined with the ICD-10 code F6.
  measure: Presence of stress-related disorders: Yes/no
  time frame: Time frame: Given within 10 years before the DanFunD baseline investigation.
  description: Defined with the ICD-10 code F43.
  arm group label: DanFunD baseline
  description: The baseline cohort (gathered in the years 2012-2015) is a random sample selected through the National Civil Registration system among people living in 10 municipalities in the western part of greater Copenhagen, Denmark, ages 18 to 76 years. The baseline cohort constitutes data from self-reported questionnaires (n=7,493) and diagnostic interviews data (n=1,590).
  arm group label: DanFunD 5-years follow-up investigation
  description: The follow-up cohort (gathered in the years 2018-2020) consists of participants all born in Denmark, between 24 and 84 years of age. The follow-up cohort constitutes data from self-reported questionnaires (n=4,288) and diagnostic interviews data (n=1,094).
  study pop: 
  sampling method: Probability Sample
  criteria: 
  gender: All
  minimum age: 18 Years
  maximum age: 84 Years
  healthy volunteers: Accepts Healthy Volunteers
  last name: Per Fink, DMSc
  role: Study Chair
  affiliation: Aarhus University Hospital
  responsible party type: Sponsor
  mesh term: Fibromyalgia
  mesh term: Fatigue Syndrome, Chronic
  mesh term: Syndrome
  mesh term: Mental Disorders
  mesh term: Problem Behavior
  mesh term: Somatoform Disorders
  sharing ipd: No
  ipd description: Restrictions apply to the availability of data according to Danish law, which means that data cannot be made publicly available. A request for collaboration or access to data can be sent to ckff@regionh.dk. An application for data should consist of a short synopsis of the study planned. Please see our website (www. danfund.org) for more information.