FR-taVNS Tinnitus Tria

Overview

Tinnitus is a common neurosensory symptom affecting 12-30% of adults and is closely associated with anxiety, sleep disturbance, and autonomic dysregulation. Current pharmacologic treatments offer limited efficacy and notable side effects, prompting interest in non-pharmacological approaches. This randomized, single-blind, sham-controlled trial evaluates whether foot reflexology (FR), transcutaneous auricular vagus nerve stimulation (ta-VNS), and auricular acupressure (AA) improve tinnitus severity, psychological distress, sleep quality, and autonomic indicators (heart rate variability and salivary cortisol) in non-cancer adults with tinnitus, compared with usual care. Participants are randomized to a foot reflexology group, an auricular vagus nerve stimulation group (each with true and sham subgroups), or a usual-care control group, and are followed at baseline and weeks 2, 4, and 8.

This is a three-arm parallel, repeated-measures randomized controlled trial conducted in the otolaryngology outpatient and inpatient settings of Hualien Tzu Chi Hospital. Eligible non-cancer adults with tinnitus as the sole chief complaint and normal pure-tone thresholds are stratified by age and sex, then randomized by computer-generated random number tables to the FR group, the ta-VNS group, or the usual-care control group; the FR and ta-VNS groups are further randomized to true or sham subgroups. The foot reflexology intervention is delivered once weekly for 20 minutes over four sessions (one month) and comprises a relaxation phase, an inner-ear/autonomic regulation phase, and a circulation/detoxification phase; the sham condition applies light, non-specific touch. The ta-VNS intervention stimulates the left tragus, cymba conchae, and cavum conchae (pulse width 250 µs, 25 Hz, 0.5-5 mA individualized to a tingling sensation, 30 s on/off) once weekly for 20 minutes over four weeks; the sham condition stimulates the left earlobe at 0.5 mA. Auricular acupressure with magnetic beads is self-administered three times daily. Outcomes are assessed at T0 (baseline), T1 (week 2), T2 (week 4), and T3 (week 8). Data are analyzed with generalized estimating equation (GEE) models.