Beyond the auditory system: cognitive implications of age-related hearing loss

Age-related hearing loss (ARHL) is one of the most common causes of disability in older adults. It is also frequently associated with neurological and neurodegenerative disorders, including dementia, as well as with stress, anxiety, depression, and social isolation. These observations suggest that ARHL should be considered not merely as a sensory dysfunction, but rather as a complex disease involving extra-auditory domains. Namely, identifying shared pathogenic determinants between hearing loss and neurodegenerative diseases remains a significant challenge. Increasing research in this field has highlighted common molecular mechanisms underlying age-related hearing and cognitive vulnerability, as well as potential overlapping neuronal networks involved in both cognitive and auditory neurodegeneration. In this review, we first outline the clinical features, risk factors, and molecular pathways involved in ARHL. We then examine the molecular mechanisms underlying ARHL at both peripheral (cochlea) and central level (auditory cortex), and subsequently discuss the cognitive comorbidities of ARHL, with a particular focus on cognitive impairment and affective disorders. From a translational point of view, exploring the extra-auditory consequences of ARHL will be crucial, as it will enable the identification of risk factors for both auditory and cognitive vulnerability and support the development of effective therapeutic interventions.