Multicentre, 3-armed, randomised, controlled study on the rapid antidepressant efficacy and safety of hyperthermic baths in depression

• Applicants: Professor Dr. Ulrich Hegerl; Professor Dr. Roman Huber
• Subject Area: Clinical Psychiatry, Psychotherapy, Child and Adolescent Psychiatry
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 500383239

Depression is the most common cause of disability worldwide. It takes several weeks for antidepressants or psychotherapy to be effective, and not all patients respond. There is a need for readily available, easily implemented adjunctive treatment options with high acceptability. Hyperthermic baths (HTB), could be a viable adjunctive treatment option with rapid symptom relief and would offer ease of implementation into routine care. HTBs have good acceptance and do not have a stigma attached to them. There would be significant public health implications if the positive results of our previous pilot randomized controlled trials could be replicated in a confirmatory study. Patients: The confirmatory study will include 348 outpatients aged 18-65 years with depression (ICD-10 F32/F33) present for at least 2 weeks and a MADRS total score ≥ 20. Suicidality, change in antidepressants ≤ 4 weeks before study entry, other mental illness, contraindications to hot baths, serious organic illness, and secondary illness gain (eg, unemployment > 6 months, pension application) are exclusion criteria. Intervention and Controls: In the multicenter, observer-blinded study, patients will be randomized 1:1:1 over 8 weeks to either HTB 2x per week plus guideline-oriented treatment (GOT) or GOT alone or thermoneutral baths 2x per week plus GOT. The latter two represent the control treatments, and the first 8 baths are performed under supervision in small groups in thermal baths or medical facilities. Our two hypotheses are that HTB plus GOT will improve depressive symptoms within 2 weeks compared with GOT alone and that HTB plus GOT will improve depressive symptoms within 2 weeks compared with thermoneutral baths plus GOT. Target parameters are primarily the MADRS score at 2 weeks and secondarily various established questionnaire scores (MADRS, self-reported depression (PHQ-9), sleep quality (PSQI), and patient satisfaction (CSQ-8) at 2, 4, and 8 weeks and 4 months after the end of the intervention. In addition, health care utilization (physician contacts, hospitalization, need for medication), work disability days, costs, and acceptability (drop-out rate) and safety (side effects) will be recorded and evaluated in the three groups. The duration of the study is planned to be four years, with 20 months for recruitment at the participating centers (commitments from 6 centers have been received).

• DFG Programme: Clinical Trials
• Co-Investigator: Dr. Gunver Kienle