Skip to main content
OpenTrials
Completed

NCT Number: NCT04511286

Exposure-Based Treatment for Undifferentiated Somatic Symptom Disorder

This study investigates the feasibility of a general exposure-based treatment protocol that is intended to work for a large variety of patient groups with a clinically significant preoccupation with physical symptoms. This is a prospective single-group study based at Karolinska Institutet, Stockholm, Sweden, where 40 adults with DSM-5 somatic symptom disorder are enrolled in 8 weeks of therapist-guided exposure-based treatment via the Internet. Exposure is based on general principles but tailored to suit the needs of each patient. Outcomes include patient-reported credibility and expectancy, adherence to the treatment protocol, client satisfaction, and negative events. Within-group effects will also be quantified and discussed in relation to the existing literature.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Somatic Symptom Disorder

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Karolinska Institutet

Stockholm, 17165, Sweden

About this study

Background:

A substantial portion of patients in routine care suffer from a recurrent preoccupation with physical symptoms, which often leads to substantial suffering and impairment. Exposure-based treatment - where the patient systematically seeks out that which gives rise to unwanted sensations, cognitions, or behavior - has been found to lead to beneficial effects in several types of symptom preoccupation. Yet, this form of treatment is rarely offered in routine care. This may be partially because existing treatment protocols have been developed for specific symptom clusters (e.g., functional somatic syndromes such as irritable bowel syndrome and fibromyalgia) or specific unwanted responses to symptoms (e.g., the fear of having a severe illness), and that many clinics do not have the resources to offer all these specialized protocols in parallel. An alternative approach could be to base exposure treatment on a more general protocol that may be tailored to suit a larger variety of patient groups who suffer from a recurrent preoccupation with physical symptoms. However, it is yet unclear if the use of such a general treatment protocol for symptom preoccupation would be feasible, for example in terms of patient-reported credibility, adherence, identification with the rationale, and general client satisfaction.

Aim:

To investigate the feasibility of delivering exposure-based treatment using a general protocol for clinically significant symptom preoccupation, without selecting patients based on any specific symptom cluster (such as a functional somatic syndrome) or specific unwanted response to physical symptoms (such as a frequent fear of illness).

Design:

This is a prospective single-group feasibility study based at Karolinska Institutet, Stockholm, Sweden, where 40 adults with somatic symptom disorder according to the Diagnostic and statistical manual of mental disorders 5 (DSM-5) are enrolled in 8 weeks of therapist-guided exposure-based treatment that is delivered via the Internet. Various aspects of feasibility are assessed; most notably: patient-reported credibility and expectancy, adherence to the treatment protocol, client satisfaction, and negative events. Within-group effects are also quantified.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • DSM-5 somatic symptom disorder
  • Interest in 8-week intensive psychological treatment to reduce distress and the impact of physical symptoms
  • At least 18 years old
  • Living in Sweden
  • Fluent in Swedish
  • Complete pre-treatment assessment

Exclusion criteria

  • Preoccupation with physical symptoms better explained by another psychiatric condition such as illness anxiety disorder, panic disorder, or obsessive-compulsive disorder
  • Severe psychiatric condition, such as bipolar disorder, suicidal ideation, or psychosis
  • Medical risks associated with participating in exposure-based treatment, or somatic condition - or treatment for somatic condition - that is an obstacle to participating in exposure-based treatment
  • Non-stable continuous pharmacotherapy (dosage changed during the past 4 weeks) and the drug is likely to affect outcome measures (primarily: antidepressants, anticonvulsants, benzodiazepines, nonbenzodiazepines, opioids)
  • Alcohol or substance use that is a clear obstacle to therapy
  • Planned absence for more than 1 week of the treatment period

Treatment and study plan

Exposure

Behavioral

Systematic confrontation with stimuli associated with symptom-related distress, to achieve therapeutic changes in cognitions or behavior

Primary outcomes

  1. Feasibility 1: Distribution of Physical Symptoms

    Time frame: Pre-treatment assessment (within 2 weeks before treatment)

    According to the Patient Health Questionnaire-15 (PHQ-15, theoretical range: 0-30, higher score indicates more distressing physical symptoms)

  2. Feasibility 2: Credibility/Expectancy Based on the Credibility/Expectancy Scale

    Time frame: Week 3 of treatment

    Theoretical range: 0-50, higher score indicates higher credibility/expectancy

  3. Feasibility 3: Adherence to the Protocol #1: Percentage Completed Modules in the Sample as a Whole

    Time frame: Adherence data collected over the entire course of the treatment, up to 8 weeks.

    Preregistered target: at least 60% completed modules in the sample as a whole. In this study, all participants were enrolled in the same type of treatment and were thus offered to work with the same treatment modules. This outcome was the proportion of modules completed in total by all participants, out of the total modules available to all participants.

  4. Feasibility 4: Patient-reported Adequacy of Rationale as Assessed Using a Questionnaire Developed Specifically for This Purpose (Theoretical Range: 0-10)

    Time frame: Post-treatment assessment (immediately after treatment, completed within 45 days)

    From 0 ("not at all relevant") to 10 ("extremely relevant"). Was originally intended to be administered at week 3, but was administered post-treatment due to an administrative error

  5. Feasibility 5: Adequacy of the Measurement Strategy

    Time frame: Post-treatment assessment (immediately after treatment, completed within 45 days)

    Preregistered target: less than 30% missing data at post-treatment, and at least 75% finding the measurement strategy acceptable (less than 7 on a scale from 0 ["Not at all stressful/bothering"] to 10 ["Extremely stressful/bothering"])

  6. Feasibility 6: Satisfaction With Treatment as Indicated by a Mean Client Satisfaction Questionnaire (CSQ-8) Score of at Least 22

    Time frame: Post-treatment assessment (immediately after treatment, completed within 45 days)

    Theoretical range: 8-32, higher score indicates higher satisfaction. This sum score is based on 8 items, each scored 1-4.

  7. Feasibility 7a: Adverse Events Measured Using Free-text Items #1: Total Number of Reported Events

    Time frame: Post-treatment assessment (immediately after treatment, completed within 45 days)

    The respondent was instructed to describe up to three adverse events.

  8. Feasibility 7b: Adverse Events Measured Using the 20-item Negative Effects Questionnaire (NEQ-20)

    Time frame: Post-treatment assessment (immediately after treatment, completed within 45 days)

    Theoretical range: 0-80, higher score indicates more severe adverse events

  9. Feasibility 3: Adherence to the Protocol #2: Percentage of Participants Completing at Least 2 Exposure Exercises

    Time frame: Adherence data collected over the entire course of the treatment, up to 8 weeks.

    Preregistered target: at least 50% of participants completing at least 2 exposure exercises

  10. Feasibility 7a: Adverse Events Measured Using Free-text Items #2: Number of Participants Who Reported at Least One Adverse Event

    Time frame: Post-treatment assessment (immediately after treatment, completed within 45 days)

    The respondent was instructed to describe up to three adverse events.

Secondary outcomes

  1. Patient Health Questionnaire-15 (PHQ-15)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), weekly during treatment, Post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-30, higher score indicates more distressing physical symptoms

  2. Somatic Symptom Disorder-B Criteria Scale (SSD-12)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), weekly during treatment, Post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-48, higher score indicates higher degree of preoccupation with symptoms

  3. Symptom Preoccupation Scale (Preliminary Scale)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), weekly during treatment, Post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Under development, higher score indicates higher degree of preoccupation with symptoms. This is to be regarded as an item pool that will be further analyzed in 2024-2025, and in conjunction with data from other clinical trials. As of September 2023, it is therefore not yet possible to provide a theoretical range for this scale, and it is also not possible to provide outcomes.

  4. 14-item Health Anxiety Inventory (HAI-14)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), Post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-42, higher score indicates more health anxiety

  5. Anxiety Sensitivity Index (ASI)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), post-treatment assessment Post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-64, higher score indicates more anxiety sensitivity

  6. GAD-7

    Time frame: Pre-treatment assessment (within 2 weeks before treatment), post-treatment assessment Post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-21, higher score indicates more general anxiety

  7. Patient Health Questionnaire (PHQ-9)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), weekly during treatments (suicidality), post-treatment assesment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-27, higher score indicates more symptoms of depression

  8. 12-item WHO Disability Assessment Schedule 2.0 (WHODAS 2.0)

    Time frame: Screening, pre-treatment assessment (within 2 weeks before treatment), post-treatment assessment (immediately after treatment, completed within 45 days), 3 months after treatment

    Change pre-post, as derived from linear mixed effects regression models fitted by maximum likelihood estimation using data from all 33 participants, and fitted on all 11 measurement points over the treatment phase (from pre-treatment to post-treatment). Theoretical range: 0-100, higher score indicates more disability

  9. Alcohol Use Disorders Identification Test (AUDIT)

    Time frame: Screening only

    Theoretical range: 0-40, higher score indicates more problematic alcohol use

  10. Drug Use Disorders Identification Test (DUDIT)

    Time frame: Screening only

    Theoretical range: 0-44, higher score indicates more problematic substance use

  11. Working Alliance Inventory (WAI)

    Time frame: Week 3 of treatment

    Theoretical range: 6-42, higher score indicates better relationship with the therapist

Sponsors and collaborators

Lead sponsor

Karolinska Institutet

Other

Registry information

Official study title

Single-Arm Feasibility Study of Exposure-Based Treatment for Undifferentiated Somatic Symptom Disorder

Acronym: SOMEX0

Important dates

Study start
2020
Primary completion
2021
Study completion
2021
First posted
Aug 13, 2020
Registry last updated
Mar 19, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.