Objectives: The aim of study is to find conditions that aggravate auditory deprivation in patients with symmetric hearing loss after unilateral digital, non-linear hearing aid (HA).
Methods: In the retrospective case-comparison study, we assessed 47 patients with symmetric sensorineural hearing loss (SNHL), wearing unilateral conventional HAs. Audiological outcomes were assessed >1 year after HA fitting (mean duration, 31.0 months). Pure-tone audiometry in HA-aided and HA-unaided conditions was performed over time. Word recognition score (WRS) was evaluated at the most comfortable listening level.
Results: The initial pure tone average of four frequency thresholds at 500, 1,000, 2,000, and 4,000 Hz (PTA4) did not show a difference of >5 dB HL between HA-aided and HA-unaided ears. WRS progressively decreased for both HA-aided and HA-unaided ears although the extent of decrease was significantly greater for HA-unaided (7.6%) than for HA-aided ears (5.1%, P<0.05). Notably, auditory deprivation in HA-unaided ears was significantly greater in patients with an initial PTA4 ≥53 dB HL (P<0.001).
Conclusion: Bilateral HAs are strongly recommended, particularly for patients with moderate to severe SNHL to prevent auditory deprivation in the contralateral ear.
Keywords: Auditory Deprivation; Sensorineural Hearing Loss; Speech Intelligibility; Unilateral Hearing Aid.