DISTRESS Trial Functional Disorders - the DISTRESS Trial

Functional Somatic Disorders (FSD) are conditions where patients present with characteristic patterns of physical symptoms, accompanied by impairment or disability. FSD is a clinical diagnosis for which no clinical or paraclinical tests at present have been found useable for establishing the diagnosis. The disorders range from mild and transient to severe, chronic and disabling, and are common in all medical settings, both in primary and secondary care. FSD is costly for society due to high health care use, and the reduction of patients' labor market participation. Arguably, insufficient diagnostic availability is part of the reason some patients develop more severe, chronic and disabling FSD. The Diagnostic Clinic for FSD was set up at Regionshospitalet to alleviate this diagnostic need in the secondary care setting.

The DISTRESS trial is a pragmatic randomized clinical trial. After referral by their GP, patients are randomized 1:1 into two study arms: Intervention and Control. The referring GP must specify which diagnostic evaluations he/she requests both in the intervention and in the control group.

Intervention arm: Patients in this arm shall be examined by an internal medicine specialist trained in FSD diagnostic evaluation at The Diagnostic Clinic for FSD. After parallel evaluation for FSD and other physical conditions, patients are given their diagnosis, along with patient education in what FSD is, as well as a letter to their GP regarding recommended management and treatment options.

Control arm: The comparison group in the randomized clinical trial will receive diagnostic as usual at the Diagnostic center or elsewhere in the secondary sector in The Central Denmark Region.

In this clinical trial, the investigators aim to evaluate the effectiveness in terms of health-related utility improvement for the patients as well as the healthcare and societal costs and cost-effectiveness of the clinic, compared to diagnostic as usual.

Study population:

Participants were drawn from the population of the Central Denmark Region. To be considered for inclusion, patients had to be referred by their GP.

Inclusion criteria

• Being referred to the clinic by their GP due to symptoms consistent with a possible diagnosis of moderate or severe FSD.
• Symptoms having been present for at least 6 months and no more than 3 years.
• Having undergone at least 2 diagnostic evaluations (e.g. imaging studies or specialist evaluations) at physical specialty clinics or hospitals in the past year.
• Age 18-60.
• Being of ethnic western cultural upbringing.
• Understands and speaks Danish fluently.

Exclusion criteria

• Having another severe chronic disease which explains the reduced level of functioning.
• Having been previously referred to or evaluated for FSD at this or another clinic specializing in functional disorders.
• Previous diagnosis of FSD.
• Alcohol or other substance-dependency or -abuse.
• Emergent psychiatric illness or emergent elevated risk of harm to self or others requiring psychiatric evaluation for possible need of acute or sub-acute psychiatric hospitalization.
• Current or prior diagnosis of psychosis (ICD10 F2x diagnosis), bipolar affective disorder (ICD10 F31.x diagnosis) or depression with psychotic symptoms (ICD10 F32.3 or F33.3 diagnosis).
• Currently pregnant.