Mild-Gain Hearing Aids as a Treatment for Adults with Self-Reported Hearing Difficulties.

Abstract

There is a growing body of evidence demonstrating self-reported hearing difficulties (HD; i.e., substantial difficulty in understanding speech in complex listening situations) in adults with normal pure-tone sensitivity. Anecdotally, some audiologists have tried personal mild-gain amplification as a treatment option for adults with HD. In 2008, Kuk and colleagues reported positive results of a mild-gain hearing aid trial for children with auditory processing disorders. To date, however, there have been no studies investigating the benefit of mild-gain amplification to treat HD in adults with normal audiograms. The effectiveness of a four-week trial with mild-gain amplification for adults with self-reported HD and clinically normal hearing sensitivity was investigated. Two participant groups with normal pure-tone audiograms (thresholds ≤20 dB HL 250-8000 Hz) were recruited to study the effects of self-reported HD on hearing handicap, self-perceived auditory processing difficulties, and performance on a speech-in-noise task. Furthermore, the benefit of mild-gain amplification was examined after a four-week hearing aid trial on self-perceived hearing handicap and auditory processing difficulties, and performance on an aided speech-in-noise task. Effects were analyzed using a mixed-model repeated measures analysis of variance. Posthoc analyses were performed for each significant main effect. Thirty-nine participants participated in two groups. Twenty normal hearing adults (19-27 yr) without complaints of HD were recruited as a control group. Nineteen normal hearing adults (18-58 yr) with self-reported HD were recruited for the mild-gain hearing aid trial. Subjective complaints of HD were assessed with two questionnaires (the Hearing Handicap Inventory for Adults [HHIA] and the Auditory Processing Questionnaire [APQ]) and an auditory processing test battery (SCAN:3-A, dichotic digit recognition, gaps-in-noise test, and the 500-Hz masking level difference). Speech-in-noise abilities were assessed before and after hearing aid trial using the Revised Speech Perception in Noise Test (R-SPIN) at multiple signal-to-noise ratios. Hearing aid use and impressions during the hearing aid trial were recorded. Results demonstrated that participants with HD perceived significantly greater hearing handicap (HHIA) and greater self-perceived auditory processing difficulties (APQ) than the control group. Participants with HD performed significantly poorer on the R-SPIN relative to controls, especially for low-predictability items. Results of the hearing aid trial for participants with HD revealed significant improvements in hearing handicap, self-perceived auditory processing difficulties, and speech-in-noise performance relative to prehearing aid trial measures. The hearing aids were well tolerated by the majority of participants with HD , with most of them wearing the hearing aids an average of 1-4 h per day. The results from the present study suggest that adults who present with complaints of HD even in the presence of normal hearing sensitivity represent a unique population that warrants further evaluation beyond the standard hearing test. Furthermore, results from the hearing aid trial suggest that mild-gain amplification is a viable treatment option for at least some individuals with HD.