Promising effects of treatment with flotation-REST (restricted environmental stimulation technique) as an intervention for generalized anxiety disorder (GAD): a randomized controlled pilot trial

Kristoffer Jonsson, Anette Kjellgren

During Flotation-REST a person is floating inside a quiet and dark tank, filled with heated salt saturated water. Deep relaxation and beneficial effects on e.g. stress, sleep difficulties, anxiety and depression have been documented in earlier research. Despite that treatments for generalized anxiety disorder (GAD) are effective; it is till the least successfully treated anxiety disorder, indicating that treatment protocols can be enhanced. The use of Flotation-REST as a treatment of GAD has not been researched. The aim of the present study was to conduct an initial evaluation of the effects in a self-diagnosed GAD sample. This study was a randomized, parallel group, non-blinded trial with 1:1 allocation ratio to waiting list control group (n = 25) or to a twelve session treatment with flotation-REST (n = 25). Inclusion criteria's were: 18-65 years and GAD (as defined by self-report measures). The primary outcome was GAD-symptomatology, and secondary outcomes were depression, sleep difficulties, emotion regulation difficulties and mindfulness. Assessments were made at three time points (baseline, four weeks in treatment, post-treatment), and at six-month follow-up. The main data analyses were conducted with a two-way MANOVA and additional t-tests. Forty-six participants (treatment, n = 24; control, n = 22) were included in the analyses. A significant Time x Group interaction effect for GAD-symptomatology [F (2,88) = 2.93, p < .001, η p (2)  = .062] was found. Further analyses showed that the GAD-symptomatology was significantly reduced for the treatment group (t (23) = 4.47, p < .001), but not for the waiting list control group (t(21) = 0.98, p > .05), when comparing baseline to post-treatment scoring. Regarding clinical significant change, 37 % in the treatment group reached full remission at post-treatment. Significant beneficial effects were also found for sleep difficulties, difficulties in emotional regulation, and depression, while the treatment had ambiguous or non-existent effects on pathological worry and mindfulness. All improved outcome variables at post-treatment, except for depression, were maintained at 6-months follow. No negative effects were found. The findings suggest that the method has potential as a complementary treatment alongside existing treatment for GAD. More studies are warranted to further evaluate the treatments efficacy. Australian New Zealand Clinical Trial Registry: ACTRN12613001105730 , Date of registration: 03/10/2013.