Hearing & Cognition-Evaluating the link between hearing loss and Alzheimer's disease neuropathology (Chandra et al 2025)

Evaluating the link between hearing loss and Alzheimer's disease neuropathology (Chandra et al 2025)

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This systematic review and meta-analysis examined whether hearing loss is associated with Alzheimer’s disease (AD) neuropathology, particularly amyloid-beta (Aβ) and tau. Researchers reviewed 22 studies identified from 6,224 records, including in-vivo biomarker studies and post-mortem research. Quantitative analyses focused on cross-sectional studies.<br /><br />Hearing loss was weakly associated with greater Aβ burden (correlation r = 0.09) and more strongly associated with greater tau burden (r = 0.16). For Aβ, significant associations appeared in studies using PET imaging and tests of central auditory processing, but not in studies using cerebrospinal-fluid measures or peripheral and subjective hearing assessments. Findings from longitudinal and post-mortem studies were mixed.<br /><br />The results suggest that AD-related pathology may be linked particularly to difficulties processing sound in the brain, rather than simply to impaired hearing in the ear. However, hearing loss could contribute to pathology, result from neurodegeneration, or share causes with it. Because most pooled evidence was cross-sectional, causality cannot be established; variation among Aβ studies and possible publication bias in tau studies also warrant caution. The authors recommend longitudinal research to clarify the direction and mechanisms of the relationship.

Keywords

hearing loss

Alzheimer’s disease

amyloid-beta

tau pathology

neuropathy

meta-analysis

systematic review

PET imaging

auditory processing

biomarkers