Project Details
Projekt
SOMACROSS.2. Targeting Mechanisms to Reduce Persistent Somatic Symptoms in Patients with Somatic Symptom Disorder: An Experimental Randomised Controlled Trial (SOMA.SSD.2)
Applicants
Dr. Kerstin Maehder; Anne Toussaint, Ph.D.
Subject Area
Public Health, Healthcare Research, Social and Occupational Medicine
Personality Psychology, Clinical and Medical Psychology, Methodology
Personality Psychology, Clinical and Medical Psychology, Methodology
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 445297796
Background: Somatic Symptom Disorder (SSD) is a prevalent condition characterised by persistent somatic symptoms accompanied by excessive symptom-related distress. Despite its widespread impact on individuals and healthcare systems, effective psychological interventions for SSD remain limited. This gap highlights an urgent need for research on targeted interventions to improve patient outcomes. Results of first funding phase: SOMA.SSD investigated risk factors for somatic symptom persistence in SSD in a 12-month cohort (n=240) with embedded ecological momentary assessment (EMA). Longitudinal analyses showed that higher symptom severity expectations, somatic comorbidity, and somatosensory amplification predicted future somatic symptom severity, with depression and physical inactivity emerging as further risk factors. EMA confirmed strong short-term links between symptom expectations and symptom severity. Objectives: SOMA.SSD.2 will test an experimental psychological intervention directly targeting the identified mechanisms of somatic symptom persistence in a cohort of patients with SSD. The trial is designed to investigate the efficacy and patient evaluation of a mechanism-based, personalised and adaptive intervention compared to care as usual (CAU). To understand the microlevel dynamics of symptoms and mechanisms, EMA and wearables will be used in embedded single-case studies. Work programme: Within a two-arm randomised controlled trial with 172 participants (86 intervention, 86 control) a mechanism-based, personalised and adaptive intervention in addition to CAU will be compared to CAU only. The intervention is CBT-based, therapist-guided, and delivered online, with 1 to 3 modules comprising 4 sessions each. After the obligatory SOMA.EXPECT module (targeting dysfunctional expectations), up to 2 out of 3 further modules are offered, based on symptom persistence and individual risk factors assessed after each module: SOMA.SYMP (symptom-related distress), SOMA.COPE (depression), and SOMA.ENGAGE (avoidance, including physical inactivity). Outcomes will be assessed at baseline, and at 1, 2, 3 (primary outcome), 6 and 12 months. A single-case subsample (n=12) will undergo intensive monitoring with EMA and wearables to capture the dynamics of symptoms, targeted mechanisms, and physiological parameters. Intervention, symptom, and healthcare experiences will be evaluated via qualitative interviews. Expected impact: SOMA.SSD.2 will provide urgently needed evidence on the efficacy of a mechanism-based, personalised, and adaptive psychological intervention for reducing somatic symptom severity in patients with SSD. It will not only examine the modifiability of targeted mechanisms but also generate in-depth insights through its embedded single-case studies and qualitative analysis. As part of SOMACROSS.2, the project adds to the transdiagnostic comparisons by uniquely targeting a mental disorder with burdensome somatic symptoms.
DFG Programme
Research Units
