Flotation Restricted Environmental Stimulation Therapy for Chronic Pain
Authors: Leonie F. Loose, Jorge Manuel, Matthias Karst, Laura K. Schmidt, Florian Beissner
Journal: JAMA Network Open (2021)

<h3>Importance</h3> Flotation restricted environmental stimulation therapy (REST) is an emerging therapeutic intervention that, to our knowledge, has never been directly compared with an indistinguishable placebo in patients with chronic pain. <h3>Objective</h3> To determine whether 5 flotation-REST sessions alleviate chronic pain. <h3>Design, Setting, and Participants</h3> This single-blind, randomized clinical trial compared flotation-REST as an intervention for the treatment of chronic pain with indistinguishable placebo and wait-list control conditions at Hannover Medical School, Hannover, Germany. Men and women aged 18 to 75 years who had been diagnosed with chronic pain disorder with psychological and somatic factors (<i>International Statistical Classification of Diseases and Related Health Problems, 10th Revision, German Modification</i>, code F45.41) by physicians at the study center were randomly assigned to 1 of the 3 groups. Data were collected from June 26, 2018, to June 18, 2020. <h3>Interventions</h3> Patients in the intervention and placebo groups underwent 5 treatment sessions lasting 60 to 90 minutes, each session separated by 4 days. The placebo treatment was delivered in the same floating tank but controlled for effortless floating and environmental stimulus restriction. Patients in the wait-list control group did not receive any additional treatment but were asked to continue any ongoing treatments at the time of enrollment. <h3>Main Outcomes and Measures</h3> The primary outcome was a change in pain intensity 1 week after the last treatment session. The assessment was repeated at 12 and 24 weeks. Secondary outcomes included pain-related disability, pain area, pain widespreadness (number of body regions affected by pain), anxiety, depression, and quality of life, as well as several other short-term outcomes. <h3>Results</h3> A total of 99 patients (mean [SD] age, 51.7 [12.3] years; 80 women [81%]) were included in the study. No differences were found among the groups in the primary outcomes (mean [SD] change in maximum pain: −7.6 [19.7] for the intervention group, −5.8 [12.7] for the placebo group, and 0.4 [14.0] for the wait-list control group; mean [SD] change in mean pain: −2.1 [19.4] for the intervention group,−4.2 [16.2] for the placebo group, and 2.0 [12.6] for the wait-list control group). Long-term secondary outcomes did not show significant differences. In the short term, patients in the intervention group showed significant improvements in pain intensity (−17.0 [17.1];<i>P</i> &lt; .001), relaxation (23.9 [22.6];<i>P</i> &lt; .001), anxiety (−10.1 [8.4];<i>P</i> &lt; .001), pain area (−3.6% [7.4%];<i>P</i> &lt; .001), and widespreadness (−2.0 [3.0];<i>P</i> &lt; .001), and similar changes where observed in the placebo group. <h3>Conclusions and Relevance</h3> Patients with chronic pain experienced no long-term benefits from the 5 flotation-REST interventions. Clinically relevant short-term changes in pain in the placebo group suggest that improvements may not be caused by environmental stimulus restriction or effortless floating as previously thought. <h3>Trial Registration</h3> ClinicalTrials.gov Identifier:NCT03584750