People experiencing hearing loss who are not using a hearing aid may have a higher risk of dementia than people without hearing loss, suggests a new study published in The Lancet Public Health journal. However, using a hearing aid may reduce this risk to the same level as people without hearing loss.
Dementia and hearing loss are common conditions among older adults. The Lancet Commission on dementia prevention, intervention, and care, published in 2020, suggested that hearing loss may be linked to around 8% of worldwide dementia cases, therefore, addressing hearing impairment may be an important way to reduce the global burden of dementia.
“Evidence is building that hearing loss may be the most influential modifiable risk factor for dementia in midlife, but the effectiveness of hearing aid use in reducing the risk of dementia in the real world remains unclear. clear. Our study provides the best evidence to date to suggest that hearing aids may be a minimally invasive, cost-effective treatment to mitigate the potential impact of hearing loss in dementia,” said the corresponding author Prof. Dongshan Zhu, Shandong University (China).
The researchers looked at data from 437,704 people who were part of the UK Biobank database. Information about the presence of hearing loss and use of hearing aids was collected through self-reported questionnaires, and dementia diagnoses were determined using hospital records and death register data. The average age of study participants at recruitment was 56 years, and the average follow-up time was 12 years.
Around three-quarters of the participants (325,882/437,704) had no hearing loss, and the remaining one-quarter (111,822) had some degree of hearing loss. Of those with hearing loss, 11.7% (13,092 / 111,822) used a hearing aid.
After controlling for other factors, the study suggests that, compared to participants with normal hearing, people with hearing loss who did not use hearing aids had a 42% higher risk of all-cause dementia, while no increased risk was found in people with hearing loss who used hearing aids.
This is estimated to equate to a 1.7% risk of dementia in people with hearing loss who do not use a hearing aid, compared to 1.2% in those who have no hearing or experience hearing loss but use a hearing aid.
“Nearly four-fifths of people experiencing hearing loss do not use hearing aids in the UK. Hearing loss can begin as early as age 40, and there is evidence that gradual cognitive decline before a diagnosis of dementia can take 20 to 25 years. Our findings highlight the urgent need for early introduction of hearing aids when a person begins to experience hearing impairment. A team effort from across society is needed, including raising awareness of hearing loss and its potential links to dementia, increasing accessibility to hearing aids by reducing cost, and greater support for primary care workers to diagnose hearing impairment, raise awareness, and deliver treatment such as appropriate hearing aids,” said Dongshan Zhu.
The researchers also examined how other factors, including loneliness, social isolation, and depressive symptoms, might affect the relationship between hearing loss and dementia. Study analysis suggests that less than 8% of the association between hearing aid use and decreased risk of dementia could be eliminated by improving psychosocial problems. The authors say this suggests that the association between hearing aid use and protection from increased dementia is likely mostly due to direct effects from hearing aids rather than the investigated indirect ones. reason.
“The underlying pathways that may link hearing aid use and reduced risk of dementia are unclear. Further research is needed to establish a causal relationship and the existence of underlying pathways,” said the study author Dr. Fan Jiang, Shandong University (China).
The authors acknowledge some study limitations, including that self-reporting is at risk of bias and that, because this study was observational, the relationship between hearing loss and dementia may be due to reverse causation through neurodegeneration or other shared mechanisms. Additionally, although many cofactors are considered, there may be unmeasured factors, such as those who use hearing aids may also be more health conscious than those who do not. Finally, the majority of participants in the UK Biobank were white, and very few participants were born deaf or experienced hearing loss before acquiring spoken language, which may limit the generalizability of the findings to other ethnicities and people with disabilities. hearing using sign language.
Writing in a Linked Comment, Prof Gill Livingston and Dr. Sergi Costafreda, University College London, who was not involved in this research: “Adding to the work of Jiang and colleagues, the evidence that hearing aids are a powerful tool to reduce the risk of dementia in people with hearing loss hearing, is as good as possible without randomized controlled trials, which may not be practically possible or ethical because people with hearing loss should not be stopped from using effective treatments. Dementia is not only a disease that affects the individual and their family but can also be costly. However, the use of hearing aids to prevent dementia has been found to be cost-effective and cost-saving. In the USA, over-the-counter hearing aids have become available, making them more accessible. The evidence is compelling that treating hearing loss is a promising way of reducing the risk of dementia. Now is the time to increase awareness and detection of hearing loss, as well as the acceptability and usability of hearing aids.”
- “Dementia prevention, intervention, and care: 2020 report of Lancet Commission” by Prof Gill Livingston, MD; Jonathan Huntley, PhD; Andrew Sommerlad, PhD; Prof David Ames, MD; Prof Clive Ballard, MD; Prof Sube Banerjee, MD; Prof Carol Brayne, MD; Prof Alistair Burns, MD; Prof Jiska Cohen-Mansfield, PhD; Prof Claudia Cooper, PhD; Sergi G Costafreda, PhD; Amit Dias, MD; Prof. Nick Fox, MD; Prof Laura N Gitlin, PhD; Prof Robert Howard, MD; Prof Helen C Kales, MD; Prof Mika Kivimäki, FMedSci; Prof Eric B Larson, MD; Prof Adesola Ogunniyi, MBChB; Vasiliki Orgeta, PhD; Prof Karen Ritchie, PhD; Prof Kenneth Rockwood, MD; Prof Elizabeth L Sampson, MD; Quincy Samus, PhD; Prof Lon S Schneider, MD; Prof Geir Selbæk, MD; Prof Linda Teri, PhD and Naaheed Mukadam, PhD, 30 July 2020, The Lancet.
- “Correlates of Hearing Aid Use in UK Adults: Self-Reported Hearing Difficulties, Social Participation, Living Situation, Health, and Demographics” by Chelsea S Sawyer, Christopher J Armitage, Kevin J Munro, Gurjit Singh and Piers D Dawes, September /October 2019, Ear and Hearing.
Reference: “Association between hearing aid use and all-cause and cause-specific dementia: an analysis of the UK Biobank cohort” by Fan Jiang, PhD; Shiva Raj Mishra, PhD; Nipun Shrestha, PhD; Prof Akihiko Ozaki, PhD; Prof Salim S Virani, PhD; Tess Bright, PhD; Prof Hannah Kuper, ScD; Prof Chengchao Zhou, PhD and Prof Dongshan Zhu, PhD, 13 April 2023, The Lancet Public Health.
This study was funded by the National Natural Science Foundation of China and Shandong Province, Taishan Scholars Project, China Medical Board and China Postdoctoral Science Foundation. See Article for full list of author affiliations.