The Association Between Early Age-Related Hearing Loss and Brain β-Amyloid.

OBJECTIVES/HYPOTHESIS To analyze the association between early audiometric age-related hearing loss and brain β-amyloid, the pathologic hallmark of Alzheimer's disease (AD). STUDY DESIGN Cross-sectional analysis of a prospective cohort study. METHODS A cross-sectional analysis was performed on 98 participants in a cohort study of hearing and brain biomarkers of AD. The primary outcome was whole brain β-amyloid standardized uptake value ratio (SUVR) on positron emission tomography (PET). The exposure was hearing, as measured by either pure-tone average or word recognition score in the better ear. Covariates included age, gender, education, cardiovascular disease, and hearing aid use. Linear regression was performed to analyze the association between β-amyloid and hearing, adjusting for potentially confounding covariates. RESULTS The mean age ± standard deviation was 64.6 ± 3.5 years. In multivariable regression, adjusting for demographics, education, cardiovascular disease, and hearing aid use, whole brain β-amyloid SUVR increased by 0.029 (95% confidence interval [CI]: 0.003-0.056) for every 10 dB increase in pure-tone average (P = .030). Similarly, whole brain β-amyloid SUVR increased by 0.061 (95% CI: 0.009-0.112) for every 10% increase in word recognition score (P = .012). CONCLUSIONS Worsening hearing was associated with higher β-amyloid burden, a pathologic hallmark of AD, measured in vivo with PET scans. LEVEL OF EVIDENCE 3 Laryngoscope, 2020.