Hearing loss charity RNID has called on the Government to include hearing in the NHS Health Check "to help millions of people in the UK identify hearing loss earlier and potentially reduce their risk of developing dementia".
Hearing loss increases the risk of dementia up to fivefold, the charity said, with hazard ratios in one study of 1.89 for mild hearing loss, 3.00 for moderate hearing loss, and 4.94 for severe hearing loss, and was responsible for up to 8.2% of dementia cases globally.
Hearing 'an Essential Part of Brain Health'
Jason Warren, professor of neurology at the Dementia Research Centre at University College London, said: "Hearing loss and dementia are linked in complex ways, but it's clear that hearing is an essential part of brain health. The impact of dementia may be delayed or reduced if hearing loss is diagnosed and treated effectively, so it's important that people get their hearing checked regularly. I strongly support this call from RNID to have a hearing check added to the NHS Health Check."
The check is offered to healthy adults aged 40-74 in England and aims to spot early signs of stroke, kidney disease, heart disease, type 2 diabetes, or dementia. But RNID said that unaddressed hearing loss in midlife was"the largest potentially modifiable risk factor for dementia", and identifying hearing loss earlier would enable people to access support and management.
According to the Office for Health Improvement and Disparities (OHID), dementia currently affects around 850,000 people in the UK, including more than 40,000 under age 65, and is the leading cause of death in England. The cost to society in the UK was estimated at £34.77 billion a year.
Hearing Loss Doubles Dementia Risk
A 2017 Lancet Commission on the prevention and management of dementia noted the nexus of hearing loss and dementia risk, and the potential for hearing aids to reduce the risk. Its 2020 report identified 12 potentially modifiable dementia risk factors, of which hearing loss in mid-life (ages 45-65) imparted an overall relative risk of 1.9 (95% CI 1.4 to 2.7), with a weighted population attributable fraction of 8.2% – higher than that of any other factor, including educational level, smoking, depression, social isolation, and traumatic brain injury.
Each 10 dB of worsening of hearing loss imparted an odds ratio (OR) for dementia of 1.3 (95% CI 1.0 to 1.6). The report further noted that midlife hearing impairment measured by audiometry was associated with steeper temporal lobe volume loss on MRI brain scans. In addition, long-term studies had found that hearing loss associated with worse cognition, but only among people not using hearing aids. "Hearing aid use was the largest factor protecting from decline," the report said.
Hearing aids have been demonstrated to mitigate the cognitive decline associated with hearing loss and to reduce the risk of progression to mild cognitive impairment, the RNID said. "Hearing aids help people with hearing loss to hear better and communicate more confidently. It is well established that they significantly improve people's ability to take part in everyday life, improving the ability to listen to others and take part in everyday situations, which could in turn delay the onset of dementia.
"Hearing aids have positive effects on a person's physical, social, emotional and mental well‐being, and are significantly associated with lower odds of depression for adults with hearing loss."
Important to Prioritise Hearing Health in Mid-life
RNID's Director of Health Crystal Rolfe said: "It's time to prioritise our hearing health, and it's especially important to do this in mid-life. Having hearing loss at a relatively young age isn't unusual: In fact, more than 40% of people over 50 have hearing loss. RNID want to see a hearing check included in the NHS Health Check to help us all look after our hearing and enable us to act quickly if there’s a problem."
OHID already recommends that as part of their support for healthy ageing, health professionals should be "aware of age related visual impairment and hearing impairment, which has been identified as a risk factor for dementia", and take action to signpost those affected to relevant services and support.
The NHS Health Check, run by local authorities and usually carried out by GP practice staff or in local pharmacies, does include explaining the early signs and symptoms of dementia to those over age 65, and aims to raise awareness of risk factors. However advice to professionals does not currently include assessment of hearing loss or test hearing specifically.
Asked by Medscape News UK how a hearing test might be incorporated, a spokesperson for RNID said: "We want to see a hearing check included in national health checks, and we suggest that integrating a hearing check within the NHS Health Check is one potential way to do this.
Hearing Test 'Achievable Way' to Reduce Dementia Risk
"While currently there is a section within the NHS Health Check on dementia risk reduction, we believe the NHS Health Check could be significantly strengthened by the addition of a hearing check. An online hearing check such as the one on RNID's website, which already features on the hearing loss page of the NHS website, could be added within a digital health check, and would support the improved access to hearing checks.
"We believe this is one achievable way of signalling a more ambitious approach to dementia risk reduction and better brain health, though other avenues must also be explored with urgency.
The RNID's free online hearing check measures ability to hear speech against background noise. It takes around 3 minutes, does not need professional input and can be done at home with a computer and a pair of headphones. Although not a full hearing test, if the results suggest possible hearing loss the person is advised to seek a formal test and given a letter to take to their GP.
Ms Rolfe added: "There is increasing evidence that acting on hearing loss when you identify it may delay cognitive decline, so it's important that we all value our hearing in the same way that we value our eyes and our teeth, and get it checked regularly."