Exposure Therapy vs. Standardized Education for Distress Related to Somatic Symptoms

The annual societal cost of medically unexplained symptoms in Sweden is approximately 40 billion SEK, i.e., similar to the annual cost of cancer. Prevalent chronic diseases like asthma and diabetes are also commonly associated with somatic symptoms that lead to significant distress and pervasive behavioral changes that result in functional impairment and place added strain on the health care system. Exposure-based treatment, where the patient willingly engages with stimuli that give rise to unwanted physical sensations or distress, has shown promise in reducing somatic symptom load and increasing quality of life in several conditions where patients commonly report substantial distress related to somatic symptoms, such as in asthma, musculoskeletal pain, and functional gastrointestinal syndromes. In routine care, however, access to such exposure-based treatment is limited. One reason for this is probably that there exists no flexible exposure-based treatment protocol that can be easily tailored to suit a wide spectrum of patient groups who suffer from distress related to recurrent somatic symptoms. In a recent single group feasibility trial (N=33) at Karolinska Institutet, Sweden, the investigators found that such a tailored exposure-based treatment delivered in an online text-based format can be acceptable, with high treatment adherence, adequate treatment satisfaction, large and lasting within-group improvement, and no serious adverse events. This is a randomized controlled trial (N=160) where the investigators aim to test if the same tailored internet-delivered exposure-based treatment is more efficacious than a standardized education control for adult patients with clinically significant distress related to somatic symptoms in a primary care setting. Primary outcome is change in self-rated somatic symptom burden as modelled using linear mixed models fitted on weekly Patient Health Questionnaire 15 sum scores over the treatment period. Long-term efficacy is assessed up to one year after treatment and cost-effectiveness is investigated based on the incremental cost-effectiveness ratio.

Inclusion Criteria: * (i) Either much bothered by at least one somatic symptom (2 points on at least one item of the PHQ-15) or at least a moderate overall somatic symptom burden (PHQ-15 sum ≥10), with (ii) recurrent distress related to somatic symptoms ≥4 months * Interested in completing an intense psychological treatment with the aim of reducing distress associated with physical symptoms * Adult (≥18 years old) * Living in Stockholm County * Can read and write in Swedish * Complete baseline assessment Exclusion Criteria: * Symptoms best explained by, or clinical picture dominated by, severe health anxiety or a non-somatoform psychiatric disorder such as depression, panic disorder, primary insomnia, a chronic stress disorder, or an acute stress disorder * Severe psychiatric condition or suicidal ideation * Clear medical risk in taking part in exposure-based treatment (e.g., pregnancy) or somatic condition (e.g., recent cancer diagnosis), or treatment for somatic condition (e.g., recent chemotherapy), makes treatment unfeasible * Continuous psychotropic medication (antidepressants, anticonvulsants, mood-stabilizers, antipsychotics) not stable in past 4 weeks, or not expected to remain stable over the main phase of the trial * Severe alcohol or substance use disorder likely to interfere with treatment * Planned absence for more than 1 week during the intended main phase