Association between hearing loss and hereditary ATTR amyloidosis.

Background

Hereditary transthyretin (TTR) related amyloidosis (ATTRv) is a life-threatening condition, which can potentially affect all organs. The objective was to identify the hearing status of patients with cardiac ATTRv and describe their audiological pattern.

Methods

Nineteen patients with confirmed diagnosis of ATTRv cardiac amyloidosis (CA) underwent otoscopy and audiological tests, including pure tone and speech audiometry.

Results

74% were male, with a mean age of 72 ± 1.8 years. The main mutations were Val122Ile (n = 7) and Val30Met (n = 6). Objective hearing loss was detected in 17 patients (89%), whereas only 37% complained of hearing loss. ATTRv patients presented a different audiometric profile compared to patients of the same age with presbycusis: a higher prevalence and worse hearing thresholds compared to age-related expectations (ISO). Hearing loss affected all frequencies with, unexpectedly, mixed or conductive hearing loss (35%). According to the type of mutation, there was an increased rate of sensorineural or mixed/conductive hearing loss.

Conclusions

the present study indicates that hearing loss is more prevalent and worse in patients with ATTRv amyloidosis than in the general population, while mostly clinically under-estimated. It suggests that ATTRv deposits could infiltrate the various anatomical structures of the inner and mild ear.