Hearing aids could help cut the risk of dementia, study finds

Wearing hearing aids could help cut the risk of dementia, according to a large decade-long study, which suggests that tackling hearing loss early may help reduce the global burden of the disease.

Dementia is one of the world’s biggest health threats. The number of people living with the condition worldwide is forecast to nearly triple to 153 million by 2050, and experts have said it presents a major and rapidly growing threat to future health and social care systems in every community, country and continent.

People with hearing loss who are not using a hearing aid may have a higher risk of dementia than people without hearing loss, research suggests. But according to the new study, using a hearing aid could reduce this risk to the same level as people without hearing loss.

The findings were published in The Lancet public health journal. It comes after the Lancet Commission on dementia prevention, intervention, and care, published in 2020, suggested hearing loss may be linked to about 8% of worldwide dementia cases.

“The evidence is building that hearing loss may be the most impactful modifiable risk factor for dementia in mid-life, but the effectiveness of hearing aid use on reducing the risk of dementia in the real world has remained unclear,” said Prof Dongshan Zhu, of Shandong University, China.

“Our study provides the best evidence to date to suggest that hearing aids could be a minimally invasive, cost-effective treatment to mitigate the potential impact of hearing loss on dementia.”

The researchers looked at data from 437,704 people taking part in the UK Biobank study. The average age was 56, and the average follow-up time was 12 years.

The researchers found that compared with people with normal hearing, those with hearing loss not using hearing aids had a 42% higher risk of all-cause dementia. There was no increased risk in people who used hearing aids.

This is approximately equivalent to a 1.7% risk of dementia in people with hearing loss who are not using hearing aids, compared with 1.2% among those without hearing loss or who are experiencing hearing loss but using the devices, the researchers said.

“Close to four-fifths of people experiencing hearing loss do not use hearing aids in the UK,” said Zhu. “Hearing loss may begin early in one’s 40s, and there is evidence that gradual cognitive decline before a dementia diagnosis can last 20 to 25 years.

“Our findings highlight the urgent need for the early introduction of hearing aids when someone starts to experience hearing impairment.

“A group effort from across society is necessary, including raising awareness of hearing loss and the potential links with dementia, increasing accessibility to hearing aids by reducing cost, and more support for primary care workers to screen for hearing impairment, raise awareness, and deliver treatment such as fitting hearing aids.”

Robert Howard, professor of old age psychiatry, at University College London, who was not involved in the study, said: “This is a large and well-conducted study, but we should always remember that association is not the same as causation.”

“I’m sceptical that use of hearing aids can be considered to prevent dementia. It seems more plausible to me that the association reflects that individuals on their way to developing dementia struggle to take up or use hearing aids.

“But hearing aids are important in reducing isolation and increasing quality of life, so we should encourage their use anyway.”