Does poor hearing increase my risk of dementia?
Poor hearing is associated with a modest but real increased risk of dementia. Have hearing loss assessed and treated in good time, but do not automatically expect a hearing aid to protect you directly against dementia.
Poor hearing does raise your risk of dementia, but not dramatically. Many large studies following people for years consistently find a modest but repeatedly observed elevated risk. An older study suggested up to five times the risk with severe hearing loss, but more recent, larger studies do not confirm this.
The more severe the hearing loss, the higher the estimated risk. However, the majority of people with hearing loss do not develop dementia. The link is an association, not a proven cause. Other factors that affect both your hearing and your brain may explain part of the connection.
Hearing loss in middle age is one of the larger risk factors for dementia worldwide that you can actually do something about. Estimates attribute roughly 9% of all dementia cases to it. The elevated risk begins before the age of 65, so acting early is in theory worthwhile.
Whether a hearing aid can genuinely prevent dementia is still unclear. Studies in people suggest that hearing aid users have a lower risk than people with hearing loss who do not use one. But in the largest study where this was actually tested, involving 977 participants, a hearing aid did not reduce the decline in thinking ability over three years in most people. Only older adults who already had more risk factors appeared to gain some benefit. A hearing aid is therefore not a proven way to broadly prevent dementia.
Why the link exists is not yet certain. It is possible that the brain has to work harder to process sounds, or that sensory input decreases. Hearing loss also tends to go hand in hand with social isolation and depression, which themselves raise the risk of dementia. This makes it difficult to determine what is a direct cause and what is a consequence.
The claims are based on several large studies following people over time (including UK Biobank, n=356,052), many studies combined looking at such long-term studies, and one study where hearing aids were actually tested against a control condition (ACHIEVE, n=977). The evidence for the association is strong; the evidence for causation and for the effect of hearing aids is moderate.
Does hearing loss increase your risk of dementia, and does a hearing aid help?
Hearing loss demonstrably increases the risk of dementia, and a hearing aid appears to help, but proven protection for everyone has not yet been established. Have your hearing assessed regardless, if only because of the other health risks associated with hearing loss.
What can I concretely do to prevent dementia?
Studies show that keeping blood pressure under control, exercising regularly, quitting smoking and having your hearing checked together have the greatest influence on your dementia risk.
Is there a link between depression and a higher risk of dementia?
Depression is strongly associated with a higher risk of dementia, though it remains uncertain whether depression causes dementia or is sometimes an early sign of it. Treating depression appears to lower the risk, so if you or someone close to you is experiencing depressive symptoms, it is worth taking them seriously and discussing them with a doctor.
Does a lithium deficiency increase the risk of dementia?
People in areas with higher lithium levels in drinking water develop dementia less often, but whether a deficiency actually causes dementia has not been proven. If you are concerned about your dementia risk, discuss it with your doctor rather than taking lithium on your own initiative.
Does poor sleep cause dementia sooner?
Poor sleep probably increases your risk of dementia, but ordinary insomnia does not make dementia inevitable. One exception: if you physically act out your dreams while sleeping, discuss that with a doctor.
Can high blood pressure in your 40s cause dementia later in life?
High blood pressure in your forties demonstrably increases your risk of dementia later in life, and early treatment appears to reduce that risk. Get your blood pressure checked and discuss with your GP whether treatment is worthwhile.