A Randomized Trial Testing a Novel Mind and Body Intervention for Depression: Cognitive Behavioral Therapy (CBT) and...

To assess the acceptability of a randomized single-blind trial of cognitive behavioral therapy (CBT) and whole-body hyperthermia (WBH) treatment for major depressive disorder (MDD).

All participants (N = 30) with MDD received CBT for depression and were randomized to also receive either: (1) WBH that raised core body temperature using an infrared sauna device, or (2) sham WBH of a similar duration that did not significantly raise core body temperature.

Study acceptability was the primary outcome: of participants who completed the final assessment (n = 29; 96.7%), 22 (75.9%) reported that they would recommend participation to a friend or family member with MDD. Twenty-five (86.2%) participants reported that they would be likely or extremely likely to enroll in this study, given the experience they had in the study. All participants randomized to WBH correctly believed they received WBH, and 6 (43%) of participants randomized to sham WBH correctly believed they received sham WBH. Both arms achieved clinically meaningful and statistically significant reductions in depression symptoms. The average decreases in the Beck Depression Inventory-II (BDI-II) were -19.07 (SE = 2.69, P < 0.0001) in the WBH arm (80.0% no longer meeting DSM-5 criteria, 60.0% achieving 50% or greater reduction in BDI-II) and -21.10 (SE = 2.41, P<0.0001) in the sham WBH arm (92.9% no longer meeting DSM-5 criteria, 78.6% achieving 50% or greater reduction in BDI-II).

Study procedures were acceptable. Participants in the WBH and sham WBH groups had substantial reductions in depressive symptoms that were greater than typically seen with CBT alone. The sham WBH arm was not fully credible and may have exerted antidepressant effects, thus raising concerns about its use in future trials. Further research to test whether adding WBH to CBT results in additional antidepressant effects is warranted.