Age-related hearing loss and Alzheimer?s disease dementia (Alzheimer?s) are distinct neurologic conditions that affect millions of older adults worldwide. Age-related hearing loss is the third most common, chronic condition and the most common sensory deficit among older adults. From prior work, we have identified hearing loss as a risk factor for dementia through epidemiologic studies. The mechanisms of how age-related hearing loss cause Alzheimer?s or whether treating hearing loss decreases the risk for Alzheimer?s, however, are unknown. For patients on the extreme end of the hearing loss spectrum with severe-profound hearing loss, the most effective form of hearing restoration is with a cochlear implant (CI). It is unknown how an intervention to restore hearing via cochlear implantation will have any cognitive benefit or will decrease the risk of developing Alzheimer?s. We hypothesize that restoring hearing via cochlear implantation in older adults with severe-to-profound sensorineural hearing loss will mitigate the risk of AD. We also hypothesize CI will improve neuropsychological well-being, as determined by clinical and social metrics, in older adults with hearing loss, thus reducing risk for Alzheimer?s. To evaluate whether CI can mitigate the risk and decrease the incidence of AD, we propose using the Utah Population Database (UPDB) to answer this important question. The Utah Population Database (UPDB) is a unique database that contains records of over 11 million individuals linked with health histories, and genealogies, spanning from the 1800?s to current day. It serves as a powerful epidemiologic tool that can be used to look at trends of incidence and prevalence of disease over time. The UPDB has not yet been utilized to evaluate cochlear implant outcomes in older adults. Using the UPDB is an innovative and novel way to evaluate the impact of hearing loss on cognition and Alzheimer?s. This project will evaluate the largest cohort of older CI recipients to be studied to answer important questions relating to aging research. Utilizing this database could provide new insights into the pathology and management of how treating hearing loss may prevent dementia. The significance of this work is to determine if hearing restoration via a CI can prevent AD in older adults with hearing loss. Completion of this study will better inform future studies looking at how hearing health can benefit older adults.
This proposal is significant to public health because of the high prevalence of severe-profound age-related hearing loss in older adults. Little is known about the collateral effects of this degree of hearing loss on non- hearing aspects of life, such as hearing loss causing Alzheimer?s disease dementia. By understanding the cognitive and quality of life impact of cochlear implantation in older adults, there is the potential to decrease Alzheimer?s disease in this patient population.
