It is de rigueur in publications on hearing loss to commence with statistics on worldwide hearing loss and disease burden, followed invariably by a sentence on the association between hearing loss and dementia.
Like Lewis Caroll’s Alice in Wonderland, we may be in danger of going down a professional rabbit hole: the attention devoted to hearing loss and dementia may become a distraction from the evidence-based importance of healthy hearing for healthy ageing, an important social responsibility.
“In our experience, public-facing documents and websites containing statements such as, ‘hearing loss is the single greatest risk factor for dementia’ are misleading because the public generally assume this is referring to personal risk.”
Where did this potentially unhelpful focus come from? The Lancet, a world-leading general medical journal, commissioned a report into dementia prevention, intervention and care has been cited over 6000 times and has further been reviewed and updated in 2020 and now 2024.
What we know and what we don’t know
We know that:
- Hearing loss is a marker of brain health (as is vision, balance, smell, touch and taste) and there is consistent evidence of an association with cognitive decline / dementia.
- Current estimates of individual risk of dementia associated with hearing loss are lower than with depression, traumatic brain injury, diabetes, low education and social isolation. Individual risk for dementia with hearing loss is generally like the risk associated with untreated vision loss, obesity, high LDL cholesterol and smoking.
- Hearing loss is important in its own right: (i) it ranks third for Years Lived with a Disability (YLD), (ii) first for sensory loss in over 70-year-olds, and (iii) impacts Quality of Life.
- Hearing aids have proven benefits for improving communication and social interactions. They facilitate wellbeing and an active, engaged, independent and healthier older age.
- Negative messaging that links hearing loss to risk of dementia is not socially responsible and may result in stigma and discourage help seeking.
We do not know:
- Whether hearing loss causes dementia because any mechanisms linking peripheral hearing loss and cortical degeneration are unknown.
- We do not know if hearing aids reduce the risk of dementia, although low-quality evidence (from observational studies) suggests interventions for hearing loss may reduce the risk of dementia. population.
From Commentary: dementia, hearing loss, and the danger of professional rabbit holes.