Acupuncture for chronic tinnitus: study protocol for a clinical trial with auditory brainstem response outcomes.

Background: Chronic tinnitus is a common clinical condition with no universally accepted effective treatment option. Increasing evidence suggests that dysfunction within the auditory pathway may contribute to tinnitus pathophysiology, and auditory brainstem response (ABR) has been proposed as a potential objective measure of auditory neurophysiological function. Acupuncture is widely used for tinnitus management; however, the relationship between acupuncture-associated symptom changes and objective electrophysiological alterations remains unclear. Objective: This study aims to investigate differences in ABR parameters between patients with chronic tinnitus and healthy controls and to explore whether clinical changes following acupuncture intervention are accompanied by alterations in auditory neurophysiological measures. Methods: This study is designed as a prospective two-part hybrid study protocol consisting of a matched case-control observational component and a longitudinal self-controlled intervention component. A total of 36 patients with bilateral chronic tinnitus and 36 age- and sex-matched healthy controls will be recruited. Both groups of participants will undergo auditory brainstem response (ABR) assessments at baseline and after treatment timepoint; in order to assess test-retest variability, the healthy control group will undergo two ABR measurements. Patients with tinnitus will receive 10 acupuncture treatments over a 4-week period. Clinical outcome measures, including the Tinnitus Handicap Inventory (THI), the Tinnitus Impact Questionnaire (TEQ), and the Tinnitus-Related Visual Analog Scale, will be assessed at baseline, after treatment, and at the 8-week follow-up. Expected results: This study will characterize baseline differences in ABR parameters between individuals with chronic tinnitus and healthy controls and will examine whether acupuncture-associated improvements in tinnitus symptoms are accompanied by changes in auditory neurophysiological measures. The findings will provide preliminary data regarding the feasibility of ABR as an objective outcome measure for future tinnitus intervention studies. Conclusion: This protocol describes an exploratory clinical study designed to evaluate clinical and neurophysiological changes associated with acupuncture intervention in chronic tinnitus. The results may contribute to a better understanding of objective electrophysiological assessment in tinnitus research and provide preliminary evidence to support future controlled clinical trials. Trial registration: https://clinicaltrials.gov/, identifier [NCT07522567].