Among the elderly, both hearing loss and dementia are highly prevalent and considered to be related. In a large new study, a team of international researchers set out to find out how the two are related.
By 2050, it is predicted that 150 million people worldwide will have dementia. Hearing loss of 20 dB or more affects 10% of those aged 40-69, 30% of those aged 65 and over, and 70%-90% of those aged 85 and over. For context, a whisper heard from 5 feet (1.5 m) away produces a sound of 20 dB.
Studies have demonstrated an association between the two conditions, suggesting that hearing loss is a modifiable risk factor for dementia. 2020 lancet A report from the Commission on Dementia Prevention found that hearing loss may be associated with about 8% of dementia cases worldwide. Therefore, addressing hearing problems in older adults, such as using hearing aids, may be a way to reduce the risk of dementia.
Several studies have investigated the relationship between hearing aid use and dementia, but the results are inconsistent. A new study by an international team of researchers explores the link between hearing aid use and dementia in middle-aged and older adults.
“Evidence is building that hearing loss may be the most influential modifiable risk factor for middle-aged dementia, but the effectiveness of hearing aid use in reducing dementia risk remains limited. It remains unknown,” said the study’s corresponding author, Dongshan Zhu. “Our study is the best yet, suggesting that hearing aids may be a minimally invasive and cost-effective treatment to mitigate the potential impact of hearing loss on dementia. We provide evidence of.”
Using the UK Biobank, researchers self-reported risk of dementia from hearing aid use and all-cause dementia versus dementia by cause, ie, Alzheimer’s disease, vascular dementia, age 40 We looked at data from 437,704 people aged between 1 and 69. , and non-Alzheimer’s nonvascular dementia.
About three-quarters of the participants had no hearing loss. The remaining quarter of them were deaf and 11.7% of them used hearing aids.
Researchers found that hearing-impaired people without hearing aids had a higher risk of dementia from all causes compared to participants with normal hearing. They found no increased risk among hearing aid users.
This means that people with hearing loss who do not use hearing aids have a risk of developing dementia of about 1.7%, compared to a risk of 1.2% for people with normal hearing or hearing aids. To do.
“Nearly four-fifths of people with hearing loss in the UK do not use hearing aids,” says Zhu. “There is evidence that hearing loss can begin as early as the 40s and that the gradual cognitive decline leading to a diagnosis of dementia can last 20-25 years. highlights the urgent need for early introduction of hearing aids when someone begins to experience hearing loss.”
The study also examined how other factors, such as loneliness, social isolation, and depression, influence the relationship between hearing loss and dementia. The data suggests that less than 8% of her in two relationships can be removed by addressing psychosocial issues. This indicates that the reduced risk of dementia is primarily due to hearing aid use rather than an indirect cause, the researchers said.
The researchers note limitations of their study, namely that self-reporting risks introducing bias, and that the association between hearing loss and dementia may be due to neurodegeneration. , US Biobank participants were Caucasian, and given that few were born deaf, the generalizability of this study may be limited.
Nonetheless, it highlights the need for a society-wide push to raise awareness of the potential link between hearing loss and dementia, in addition to improving the accessibility of hearing aids.
Further research is needed to clarify the causal relationship between hearing loss and dementia.
“The underlying pathways linking hearing aid use with reduced risk of dementia are unknown,” said Huang Jiang, the study’s lead author. “Further studies are needed to establish causality and the existence of underlying pathways.”
The study was published in a journal lancet public health.
Source: University of Melbourne/University of Sydney/Shandong University via Simex
