Pathophysiological and Clinical Aspects of Hearing Loss Among 85-Year-Olds.

ABSTRACT

PURPOSE: This study aimed to identify the prevalence of conductive/mixed and sensorineural hearing loss, with an attempt to differentiate between sensory and neural components in 85-year-olds. METHOD: A comprehensive auditory test protocol, including pure-tone audiometry, speech audiometry, auditory brainstem response (ABR), and distortion product otoacoustic emission (DPOAE), was used to identify different types of hearing loss in 85-year-olds. This study comprised a subsample (n = 125) selected from an unscreened cohort of 85-year-olds born in 1930, within the Gothenburg H70 Birth Cohort Studies in Sweden. RESULTS: Test results were reported descriptively. Sensorineural hearing loss was present in one or both ears in almost all participants (98%), and the majority had absent DPOAEs. Only approximately 6% had additional conductive hearing loss, that is, mixed hearing loss. Approximately 20% of the participants with a pure-tone average at 0.5-4 kHz < 60 dB HL had worse word recognition scores compared with predicted scores by the Speech Intelligibility Index (SII), whereas only two participants were classified with neural dysfunction with the use of ABR. CONCLUSIONS: Sensorineural hearing loss, likely related to outer hair cell loss, was present in the vast majority of 85-year-olds. Conductive/mixed hearing loss appears to be relatively rare in advanced age. Poor word recognition scores in relation to SII-predicted scores were relatively common (20%) in 85-year-olds, whereas auditory neuropathy was only rarely identified (1.6%) by the use of ABR latencies. To explain abnormal word recognition and to identify the neural component of hearing loss among the older-old population, future research should consider factors such as listening effort and cognition among the older-old population.