Early signs of auditory aging: Hearing declines faster in individuals with extended high frequency hearing loss.

Hearing loss, particularly age-related hearing loss, significantly impacts health and quality of life worldwide. While much of the research has focused on older adults, the early stages of hearing decline remain relatively unexplored. Longitudinal studies examining hearing changes across the adult lifespan, especially at extended high frequencies (EHFs), are scarce. This prospective longitudinal study aimed to explore the rate of hearing threshold shift in young adults with clinically normal audiograms and to assess whether EHF hearing loss could predict future hearing decline in the standard audiometric range. Hearing thresholds were measured at standard audiometric frequencies (0.25 to 8 kHz) and EHFs (10, 12.5, 14, and 16 kHz) in 71 participants (24 females) aged 19 to 38 years (mean age = 27.8 years). Two testing sessions were conducted nearly 24 months apart. Results revealed that the annual rate of threshold shift was significantly higher for EHFs compared to standard audiometric frequencies. A higher EHF threshold, measured in the initial test session, was associated with a greater rate of threshold shift at standard audiometric frequencies, suggesting that EHF hearing loss may serve as an early marker for subsequent hearing decline. Even with a normal audiogram, individuals with EHF hearing loss are at an increased risk of accelerated hearing deterioration. These findings show preclinical, age-related changes in young adults with normal audiograms and underscore the importance of early detection and monitoring of EHF hearing loss to mitigate the impact of future hearing loss on their overall health and well-being.