Dementia-related hearing loss in older adults
Abstract: Older adults with more severe hearing loss are more likely to suffer from dementia, but those who use hearing aids are less likely to develop dementia.
Source: Johns Hopkins University
A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health found that older adults with more severe hearing loss are more likely to have dementia, but the likelihood of dementia is lower among hearing aid users compared to non-users.
The findings, obtained from a nationally representative sample of more than 2,400 older adults, are consistent with previous studies showing that hearing loss may be a factor that contributes to the risk of dementia over time, and that treating hearing loss can reduce the risk of dementia.
The findings are highlighted in a research letter published online Jan. 10 in the Journal of the American Medical Association.
“This study clarifies what we have observed about the link between hearing loss and dementia and builds support for public health actions to improve access to hearing care,” says lead author Alison Huang, PhD, MPH, senior research fellow in the Bloomberg School’s Department of Epidemiology and the Cochlear Center. for Hearing and Public Health, also at the Bloomberg School.
Hearing loss is a critical public health problem affecting two-thirds of Americans over the age of 70. The growing realization that hearing loss may be associated with the risk of dementia, which affects millions, and other adverse outcomes has drawn attention to the implementation of possible strategies to treat hearing loss.
For the new study, Huang and colleagues analyzed a nationally representative data set from the National Health and Aging Trends Study (NHATS). Funded by the National Institute on Aging, NHATS has been conducted since 2011 and uses a national sample of Medicare beneficiaries age 65 and older, with a focus on the 90-and-older group, as well as blacks.
The analysis included 2,413 people, about half of whom were older than 80, and showed a clear link between the severity of hearing loss and dementia. The prevalence of dementia among participants with moderate/severe hearing loss was 61 percent higher than the prevalence among participants who had normal hearing. Hearing aid use was associated with a 32 percent lower prevalence of dementia in 853 participants who had moderate/severe hearing loss.
The authors note that many previous studies were limited in that they relied on in-clinic data collection, leaving out vulnerable populations who did not have the means or capacity to reach a clinic. For their study, researchers collected data from participants through home testing and interviews.
How hearing loss is related to dementia is not yet clear, and studies point to several possible mechanisms. Huang’s research builds on work from the Cochlear Center for Hearing and Public Health examining the relationship between hearing loss and dementia.
The study authors expect to get a more complete picture of the effect of hearing loss treatment on cognition and dementia from their Aging and Cognitive Health in the Elderly (ACHIEVE) study. The results of the three-year randomized trial are expected this year.
“Hearing Loss and Prevalence of Dementia in Older Adults in the United States” is co-authored by Alison Huang, Kening Jiang, Frank Lin, Jennifer Deal, and Nicholas Reed.
Financing: The research was supported by the National Institute on Aging (K23AG065443, K01AG054693).
Reported findings of co-authors: Nicholas Reed, AuD, is a member of Neosensory’s scientific advisory board. Frank Lin, MD, PhD, is a consultant for Frequency Therapeutics and Apple and director of a research center funded in part by a philanthropic gift from Cochlear Ltd to the Johns Hopkins Bloomberg School of Public Health. Lin also serves on the board of the nonprofit organization Access HEARS.
About this hearing loss and dementia research news
Original research: Closed access.
“Hearing loss and the prevalence of dementia in the elderly in the United States” Alison Huang et al. PIT
Hearing loss and the prevalence of dementia in the elderly in the United States
Hearing loss accounts for 8% of global dementia cases, making it the largest modifiable risk factor for dementia at the population level. However, there are few nationally representative estimates of the association between hearing loss and dementia among older adults in the US.
Previous estimates have been susceptible to selection bias and have typically used self-reported data, which may underestimate hearing and dementia and may not reflect the true association at the national level. In addition, the use of hearing aids may potentially reduce the risk of dementia among older people with hearing loss, but the evidence is limited and mixed.
We assessed the cross-sectional association of audiometric hearing loss and hearing aid use with dementia among community-dwelling older adults using a nationally representative dataset of US Medicare beneficiaries.