Can Hearing Aids Prevent Dementia? What the ACHIEVE Trial Actually Found

No. Current evidence does not show hearing aids prevent dementia for everyone. In the ACHIEVE trial, hearing aids did not slow cognitive decline across the whole group. But in a higher-risk older subgroup, cognitive decline was slower. Treating hearing loss is a low-risk, supportable step — not a guaranteed shield.

What did the ACHIEVE trial actually find?

ACHIEVE randomised older adults with untreated hearing loss to either a hearing intervention (hearing aids plus audiologist support) or a health-education control, then followed them over time. Across the full study population, the hearing intervention did not reduce cognitive decline.

That headline matters. It means the honest answer to "can hearing aids prevent dementia?" is that we cannot claim they do.

The nuance sits inside the trial. ACHIEVE included both older adults who already carried more health risk factors and healthier community volunteers. In the higher-risk group, hearing aids were associated with a slower rate of cognitive decline. In the healthier group, there was little measurable difference.

Why did results differ between the two groups?

People with more risk factors simply had more cognitive change to slow down over the follow-up. In the healthier group, decline was so gradual that any effect was hard to detect in a shorter window.

This is a signal worth taking seriously, but it is a subgroup finding, not proof for the population as a whole. Subgroup results generate strong hypotheses; they do not settle them. The researchers were clear that the effect might apply to higher-risk older adults and needs confirmation.

So is treating hearing loss still worth it for the brain?

Yes, as part of a bigger picture. The 2024 Lancet Commission on dementia lists hearing loss among 14 modifiable risk factors that together account for a large share of potentially preventable dementia cases. Alzheimer Europe's summary of that report groups hearing loss with factors that could, in theory, reduce dementia risk if addressed across a population (Alzheimer Europe, 2024).

"Modifiable risk factor" means association plus biological plausibility — untreated hearing loss increases listening effort and social withdrawal, both linked to brain health. It does not prove that fixing hearing removes the risk. Association is not causation.

There are also plain, day-one reasons to treat hearing loss: clearer conversations, less fatigue, and staying socially connected. Age-related hearing loss is common and typically gradual (NIDCD). In the United States, about one in eight people aged 12 and older have hearing loss in both ears (NIDCD statistics), and the World Health Organization estimates that around 430 million people worldwide live with disabling hearing loss (WHO). Those benefits are real regardless of the dementia question.

Should I get hearing aids specifically to protect my memory?

Buy hearing aids to hear better first. Treat any cognitive benefit as a possible bonus, not the reason.

If you or a family member has noticed difficulty following conversations, turning the TV up, or missing speech in noise, the right next step is a diagnostic hearing test — not an online purchase. Many people underestimate their loss, and undiagnosed medical causes (such as wax, fluid, or one-sided loss) need ruling out first.

You can book a full assessment through our hearing test service, and we offer a home visit if travelling to the clinic is difficult. If a device is appropriate, our audiologists fit and fine-tune it during follow-up — the same audiologist-supported model used in ACHIEVE, which is quite different from buying an unadjusted amplifier.

For the wider evidence on hearing, the brain, and what you can actually do, read our pillar guide: Hearing Loss and Dementia: What the 2024 Lancet Commission Really Says (and What You Can Do).

When to seek urgent care: sudden hearing loss in one or both ears should be treated as urgent. Do not wait for a routine appointment — seek prompt medical or ENT assessment.