Purpose
To examine whether or not breathing relaxation, using a huggable human-shaped device, improves poor sleep quality in adults.

Methods
We conducted a randomized controlled trial using outpatients with sleep problems from two clinics in Japan. The intervention group conducted three minutes of breathing relaxation using a huggable human-shaped device before going to bed every night for four weeks. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), at pre-intervention, mid-intervention (2 weeks after pre-intervention), and post-intervention (4 weeks after pre-intervention). We employed intention-to-treat analysis.
 

Results
A total of 68 participants (mean [SD] age, 41.7 [11.4] years; 64 female [95%]) were randomly assigned to the intervention group (n = 29, mean [SD] age, 43.6 [9.5] years; 28 female [97%]) and the control group (n = 36, mean [SD] age, 40.3 [12.7] years; 36 female [95%]). The intervention group showed a significant decrease in the PSQI score compared to the control group (F = 3.81, p = 0.025, effect size (η²) = 0.057). Furthermore, we found the intervention to be more effective in participants without suicide risk and with a lower number of adverse childhood experiences (effect size (η²) = 0.080 and 0.160, respectively).
 

Conclusions
A novel psychological intervention, breathing relaxation using a huggable human-shaped device, may be effective to improve sleep quality among people with sleep problems, especially those without severe psychological symptoms.

Trial Registration: UMIN000045262. (Registration Date: September 28th, 2021).

•  
• Takeo Fujiwara, Professor
  
  Department of Global Health Promotion,
  Graduate School of Medical and Dental Sciences, 
  Tokyo Medical and Dental University (TMDU)
  E-mail：fufujiwara.hlth(at)tmd.ac.jp
  
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