The Impact of Daily Hours of Sound Therapy on Tinnitus Relief for People With Chronic Tinnitus: A Randomized Controlled Study

Purpose: Tinnitus is defined as the perception of sounds in the absence of extrinsic sound stimuli. Sound therapy is an option for tinnitus rehabilitation, which aims to mitigate the functional and emotional effects of tinnitus. Several studies have reported that a longer duration of sound therapy may result in a greater tinnitus relief effect. However, the relationship between the daily hours of sound therapy and the tinnitus relief effect remains unclear. Thus, we aimed to evaluate the tinnitus relief effect according to the time spent in daily perform-ing sound therapy.Method: Fifty-eight chronic tinnitus participants were randomly assigned to three groups according to their daily hours of sound therapy (1-hr, 3-hr, and 5-hr groups), and mixing point-based sound therapy, which adjusts the volume of the external stimulus to blend with the participant's tinnitus sound, was admin-istered for 3 months. The effectiveness of sound therapy was determined based on changes in the tinnitus loudness level, visual analog scale for loudness score, and the Korean version of the Tinnitus Primary Function Questionnaire (K-TPFQ) score between the baseline and 3-month time points.Results: Longer daily sound therapy hours were associated to a greater effect of sound therapy in the tinnitus loudness level and the total K-TPFQ scores, including the emotion and hearing subcategories. Particularly, the 3-hr and 5-hr groups showed a greater tinnitus relief than the 1-hr group.Conclusion: An increase in the daily sound therapy hours may increase the possibility of improving tinnitus relief effects.