Mie L. Jørgensen1,2, Petteri Hyvärinen1, Sueli Caporali2, Torsten Dau1
1Hearing Systems Section, Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
2WS Audiology, Lynge, Denmark

The objective of the study was to investigate the effect of broadband amplification (125 Hz to 10 kHz) as tinnitus treatment for subjects with high-frequency hearing loss and compare these effects with an active placebo condition using band-limited amplification (125 Hz to 3-4 kHz). The study was a double-blinded crossover study. 22 subjects with a high-frequency (≥ 3 kHz) hearing loss and chronical tinnitus were included in the study and 17 completed the full treatment protocol. Two different hearing aid treatments were provided for 3 months each: broadband amplification that provided gain in the frequency range from 125 Hz to 10 kHz and band-limited amplification that only provided gain in the low frequency range (≤ 3-4 kHz). The effect of the two treatments on tinnitus distress was evaluated with the tinnitus handicap inventory (THI) and the tinnitus functional index (TFI) questionnaires. The effect of the treatment on tinnitus loudness was evaluated with a visual analog scale (VAS) for loudness and a psychoacoustic loudness measure. Furthermore, the tinnitus annoyance was evaluated with a VAS for annoyance. A statistically significant difference was found between the two treatment groups (broadband vs. band-limited amplification) for the treatment-related change in THI and TFI with respect to baseline. Furthermore, a statistically significant difference was found between the two treatment conditions for the annoyance measure. Regarding the loudness measure, no statistically significant differences were found between the treatments, although there was a trend towards lower VAS-based loudness measure resulting from the broadband amplification. No changes were observed for the tinnitus pitch between the different conditions. Overall, the results from the present study suggest that, tinnitus patients with high-frequency hearing loss can experience a decrease in the tinnitus related distress, annoyance and loudness from high-frequency amplification.