Hearing loss can increase the risk of developing dementia and mild cognitive impairment, research shows.
The research published in Ageing Neuropsychology and Cognition, and based on a six-year Australian study, indicates that up to nine per cent of new dementia cases could be prevented by addressing midlife hearing loss.
That’s the highest of any potentially modifiable dementia risk factor.
Hearing loss affects 74 per cent of Australians aged over 70 and it’s estimated that people with severe hearing loss are up to five times more likely to develop dementia.
The six-year study used data from the Sydney Memory and Ageing Study involving 1,037 men and women aged between 70 and 90.
People with moderate-to-severe hearing difficulties performed worse in cognitive tasks and had a 1.5 times greater risk of developing dementia or mild cognitive decline over the next six years.
This may be because hearing loss can “increase cognitive load”, the researchers say.
Lead researcher Dr Paul Strutt from Macquarie University’s Department of Cognitive Science, says the research could point to ways of reducing dementia risk.
“The presence of hearing loss is an important consideration for neuropsychological case formulation in older adults with cognitive impairment,” he writes.
Co-author Professor Henry Brodaty, co-director of the University of NSW’s Centre for Healthy Brain Ageing (CHeBA), says it’s the first study of its kind to identify the relationship between hearing loss and dementia.
Dr Brodaty says the study suggests that hearing aids could help improve cognitive function and advocates further investigation.
“Studies are now emerging that hearing aids may reduce this risk. Large, multi-centre trials examining the wide-ranging benefits of hearing interventions in older adult populations with hearing loss could determine the potential for risk reduction associated with this significant and modifiable risk factor for MCI and dementia in older age,” he said.