Hearing in Sickle Cell Disease: Cochlear and Subcortical Dysfunction without Cortical Impairment

To simultaneously evaluate peripheral and central auditory pathways in individuals with sickle cell disease (SCD), identifying patterns of auditory impairment and potential initial sites of lesion.

This cross-sectional study included 107 participants (aged 7-49 years), 54 with SCD (HbSS or HbSC) and 53 controls (HbAA). Participants with abnormal otoscopic findings, comorbidities, or auditory risk exposures were excluded. Assessments included pure-tone audiometry, tympanometry, contralateral acoustic reflex testing, brainstem auditory evoked potentials (BAEP), and cortical auditory evoked potentials (P300). Clinical data, hydroxyurea use, and transfusion history were collected. Statistical analyses included association tests and binary logistic regression.

Sensorineural hearing loss (SNHL) was present in 29.6% of the SCD group, significantly higher than in controls (p < 0.001). Among participants without SNHL, elevated contralateral acoustic reflex thresholds were more frequent, particularly at 2 and 4 kHz in both ears (p < 0.05). No significant differences were observed in BAEP absolute or interpeak latencies, nor in P300 latency between groups. Logistic regression did not identify independent clinical predictors of SNHL.

Individuals with SCD exhibit a high prevalence of SNHL and subclinical auditory dysfunction. Although BAEP and P300 responses did not differ between groups, alterations in contralateral acoustic reflex thresholds suggest early and localized dysfunction at the level of brainstem auditory circuits, even in individuals with normal hearing thresholds. These subclinical findings highlight the importance of regular audiological monitoring using sensitive objective measures to enable early detection and longitudinal follow-up of auditory changes in this population.