Which Came First, Age-Related Hearing Loss with Tinnitus or Cognitive Impairment? What are the Potential Pathways?

Author: Qingwei Ruan1,2, Bing Chen3,4, Francesco Panza5,6
Affiliation: <sup>1</sup> Laboratory of Aging, Anti-aging &amp; Cognitive Performance, Shanghai Institute of Geriatrics and Gerontology, Fudan University, 200040 Shanghai, China. <sup>2</sup> Shanghai Key Laboratory of Clinical Geriatrics, Huadong Hospital, Shanghai Medical College, Fudan University, 200040 Shanghai, China. <sup>3</sup> ENT Institute and Department of Otorhinolaryngology, Eye &amp; ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, 200031 Shanghai, China. <sup>4</sup> NHC Key Laboratory of Hearing Medicine, Fudan University, 200032 Shanghai, China. <sup>5</sup> Department of Translational Biomedicine and Neuroscience &quot;DiBraiN&quot;, University of Bari Aldo Moro, 70121 Bari, Italy. <sup>6</sup> Unit of Research Methodology and Data Sciences for Population Health, National Institute of Gastroenterology &quot;Saverio de Bellis&quot; Research Hospital, Castellana Grotte, 70121 Bari, Italy.
Conference/Journal: J Integr Neurosci
Date published: 2023 Aug 4
Other: Volume ID: 22 , Issue ID: 5 , Pages: 109 , Special Notes: doi: 10.31083/j.jin2205109. , Word Count: 206


Research on the causal relationship between age-related hearing loss (ARHL) and/or tinnitus and dementia is an important and fast-moving field. In this opinion paper, the up-to-date evidence and potential mechanisms for the bidirectional relationship are reviewed. We also present several critical factors that increase the challenges of understanding the causal relationship. These factors include common causes (such as aging, frailty, vascular impairment, and chronic inflammation), auditory and cognitive reserves, and the difficulty in distinguishing central auditory processing disorder (CAPD) from cognitive impairment. Finally, based on cumulative evidence, we propose an integrated mechanism in which the central auditory system might be the common target of both peripheral auditory impairment and dementia or its precursor. There is a bidirectional interaction between the peripheral and central auditory systems and between the central auditory systems and the cognitive brain. CAPD causes the depletion of auditory and cognitive reserves, and indirectly affects the peripheral auditory system via the auditory efferent system. According to the proposal, multimodal intervention might be beneficial for patients with ARHL and/or tinnitus and cognitive impairment, apart from hearing restoration by hearing aids or cochlear implants.

Keywords: auditory reserve; cognitive impairment; cognitive reserve; dementia; frailty; hearing loss; hearing restoration; multimodal intervention; tinnitus.

PMID: 37735130 DOI: 10.31083/j.jin2205109