Validation of a novel combination hearing aid and tinnitus therapy device

Most patients with tinnitus also have hearing loss. Hearing aids have been well-documented to provide amelioration for both hearing and tinnitus problems. Some hearing aids have built-in noise/sound generators that are intended to provide added benefit to patients with tinnitus. It has not been proven, however, whether these "combination instruments" are more effective for tinnitus management than hearing aids alone. The purpose of this study was to collect initial data addressing this question.

Thirty individuals meeting study requirements (bothersome tinnitus, hearing aid candidate, and no use of hearing aids for the previous 12 months) were enrolled. All participants initially completed the primary outcome questionnaire (Tinnitus Functional Index [TFI]) and then returned to be fitted with combination instruments. The hearing aid portion of the devices was adjusted to optimize hearing ability. Participants were then randomized to either the experimental group (n = 15) or the control group (n = 15). The experimental group had the noise feature of the instruments activated and adjusted to achieve optimal relief from tinnitus. The control group did not have the noise portion activated. Following the hearing aid fitting, all study participants also received brief tinnitus counseling. Participants returned 1 to 2 weeks later for a follow-up appointment to confirm proper fit of the instruments and to make any necessary programming adjustments. Additionally, they returned 3 months after the fitting to complete the TFI, which also concluded their participation in the study.

Both groups revealed significant improvement, as indicated by reductions in mean TFI index scores. Differences between groups at 3 months were not statistically significant. However, the experimental group showed a mean reduction in the TFI score that was 6.4 points greater than that for the control group. The difference approached significance (p = 0.09), suggesting that a larger group of participants may have resulted in a significant difference between groups. This possibility is tempered by the fact that effect sizes, which control for variation, were very similar between groups.

Results of this study suggest that the use of hearing aids alone or hearing aids plus the use of sound generators both provide significant benefit with respect to alleviating effects of tinnitus. A larger controlled clinical trial is needed to obtain more definitive results regarding the two configurations of hearing aids.