Tinnitus has been linked to dementia in several large studies, but when UK Biobank researchers accounted for measured hearing loss, the link weakened or vanished. Hearing loss is the established risk factor; the case against tinnitus itself is thin.
The worry usually arrives in a particular order: someone reads that hearing loss raises the risk of dementia, notices the ringing they have had for years, and wonders whether it is an early warning. Two bodies of evidence get blurred in that moment. The hearing-loss evidence is large, recent and taken seriously by the 2024 Lancet Commission on dementia. The tinnitus evidence is a handful of observational studies that point in different directions, and the most careful of them point away from tinnitus.
Why hearing loss is the established risk factor
The 2024 update of the Lancet Commission on dementia lists 14 potentially modifiable risk factors, hearing impairment among them, and estimates that together they account for nearly half of dementia, which in theory could be prevented or delayed by removing them. Tinnitus is not one of the 14.
For hearing loss, the Commission ran its own meta-analysis of six cohort studies, 666,370 participants in all, chosen because they measured hearing objectively and followed people for more than five years. People with hearing loss had a higher risk of dementia than people with normal hearing (hazard ratio 1.37, 95% CI 1.00 to 1.87). The lower bound touches no effect and the studies disagreed considerably (I² = 80%), but the Commission calls it a conservative estimate, because hearing aid users were counted alongside everyone else. All four studies that looked at severity found risk rising as hearing worsened, by between 4% and 24% for every 10 dB of hearing lost.
How hearing loss might raise the risk is still hypothesised. The Commission's candidates include loneliness, depression and social isolation, less stimulation for the brain, the extra mental effort of listening, and cardiovascular disease damaging both ear and brain. Its practical recommendation is that hearing aids be accessible to people with hearing loss, and that hearing loss be reduced by lowering harmful noise exposure.
Age-related hearing loss and tinnitus covers why a population risk factor is not a prognosis for any one person.
What the tinnitus studies found
The studies that test tinnitus directly against later dementia are few, and the main ones come from two sources: Taiwan's national health insurance records and UK Biobank.
- Taiwan, 2020, cohort. 12,657 people with a recorded tinnitus diagnosis and 25,314 matched controls were followed for a median of about 7.4 years. Alzheimer's disease was diagnosed in 3.1% of the tinnitus group and 2.0% of controls, an adjusted hazard ratio of 1.54. The model did not include hearing loss, and the authors note that education and depression were not available.
- Taiwan, 2021, case-control. Among 1,308 people diagnosed with dementia before 65 and 1,308 matched controls, 21.5% of cases had an earlier tinnitus diagnosis against 14.5% of controls (adjusted odds ratio 1.63). Hearing loss was counted only as a recorded diagnosis, and the authors note that no hearing test results were available.
- Taiwan, 2024, case-control. In 7,843 people with dementia and 7,843 controls, adjusted for recorded hearing loss, a history of tinnitus was linked with dementia diagnosed between 50 and 64 (adjusted odds ratio 2.68, 95% CI 1.19 to 6.05). It was not linked with dementia diagnosed at 65 or older (1.17, 95% CI 0.90 to 1.51).
- UK Biobank, 2024. Analysing a cohort of 502,382 people aged 40 to 70 at recruitment, the researchers found tinnitus on its own was associated with dementia. When hearing loss, age and other covariates were added, the effect vanished. Hearing loss, measured as a speech-reception threshold, was linked with dementia: each 1 dB worse raised the risk by 14.0%.
- UK Biobank, 2025. Among 160,032 participants followed for a median of 12.8 years, 2,219 developed dementia. Reporting tinnitus carried a hazard ratio of 1.10 (95% CI 1.00 to 1.20), a 10% higher risk whose lower bound sits at no effect. The main model did not include hearing loss. When it was added, the authors write, the association "became weak".
Every one of these is observational, so none can show that tinnitus causes anything. The UK Biobank tinnitus study explains what that cohort can and cannot tell you about the wider population.
Why measuring hearing changes the answer
Tinnitus and hearing loss travel together. In a 2026 German population study, self-reported hearing loss was strongly associated with tinnitus (odds ratio 7.5, 95% CI 6.0 to 9.3). Tinnitus and hearing loss explains why: the leading account of tinnitus starts with damage to the inner ear.
That makes tinnitus a marker of hearing loss. A study that cannot see hearing loss will find tinnitus "predicting" dementia whether or not tinnitus contributes anything, because it is standing in for the hearing loss behind it. The two UK Biobank analyses are the ones that measured hearing directly, and they are the ones where the tinnitus signal faded.
The 2025 authors raise a fair counterpoint: adjusting for hearing loss may be over-adjustment, since the two conditions are so closely related. That is possible. It also means these data cannot show that tinnitus adds anything hearing loss does not.
The same German study, from the Study of Health in Pomerania, looked at 4,420 adults aged 20 to 84, including 874 who reported tinnitus. Self-reported hearing loss went with worse memory scores and unfavourable measures on brain MRI. Tinnitus alone was associated with neither. It is cross-sectional and self-reported, a snapshot rather than a follow-up, but it points the same way.
Does bothersome tinnitus matter more than the sound?
This is the one tinnitus finding in UK Biobank that survived adjustment for measured hearing loss. In the 2025 UK Biobank study, among people with tinnitus, those slightly bothered by it had a hazard ratio for dementia of 1.23, and those moderately or severely bothered had 1.64, compared with people not bothered at all. After further adjustment for hearing loss, sleep disturbance and depression, severity was still associated with dementia (hazard ratio 1.57, 95% CI 1.27 to 1.94).
Why that would be is not known. Depression is itself one of the Commission's 14 risk factors, but severity kept its association after depression was adjusted for. The finding rests on one study and on a single self-reported question about how much the noises worry, annoy or upset people, and the authors acknowledge that self-report introduces some information bias.
On thinking tests rather than dementia, there is more evidence. A 2020 meta-analysis of 38 study records with 1,863 participants found that people with tinnitus scored worse on executive function, processing speed, short-term memory, and learning and retrieval. The authors add their own cautions: the short-term memory result was driven by two studies and appeared confounded by hearing loss, and depression may explain part of the processing-speed result. These are scores on thinking tests, not diagnoses of dementia.
Distress may be the more important variable. In a 2021 study of 107 people with chronic tinnitus, distress was the strongest predictor of attention and interference test scores, and the authors report no meaningful relationship between hearing loss and performance; they call the link with distress currently non-causal. And not every study finds a deficit: a US analysis of adults aged 60 to 69 found no association between tinnitus and cognition in most groups, and in one subgroup tinnitus went with better scores. Tinnitus and focus covers the attention side, and tinnitus and depression the mood side.
A meta-analysis worth reading past the abstract
A 2024 meta-analysis of 17 studies concluded that tinnitus has the potential to increase the risk of cognitive impairment, and its discussion describes a strong association between tinnitus and dementia. Its own pooled estimate for dementia, from five studies, was an odds ratio of 1.27 (95% CI 0.97 to 1.65, p = 0.08), a result that does not rule out no effect at all. Several of the studies in its table of included research measured hearing impairment rather than tinnitus.
It is a clear example of why the numbers matter more than the headline.
Do hearing aids protect against dementia?
The most direct test is the ACHIEVE trial, published in The Lancet in 2023. It randomised 977 adults aged 70 to 84 with untreated hearing loss to a hearing intervention, meaning audiological counselling and hearing aids, or to health education. Over 3 years, cognition declined by the same amount in both groups: −0.200 and −0.202 standard deviations, a difference of 0.002 (p = 0.96).
A prespecified sensitivity analysis found the effect differed between the two populations the trial recruited. In participants drawn from a long-running heart-health study, who were older and had more risk factors, the Lancet Commission reads the result as a 48% protective effect. A 2025 secondary analysis found that in the quarter of participants at highest predicted risk, decline was 61.6% slower with the hearing intervention. These are subgroup findings inside a trial whose main result was null, which makes them a lead worth following rather than a conclusion.
The observational evidence is more favourable. A 2023 meta-analysis of 8 studies with 126,903 participants, followed for 2 to 25 years, found hearing aid users had a 19% lower risk of cognitive decline than people with uncorrected hearing loss (hazard ratio 0.81, 95% CI 0.76 to 0.87). Its authors say a cognitive benefit should be investigated further in randomised trials, and with reason: an observational comparison cannot rule out that people who choose hearing aids differ in other ways from people who do not. The 2024 Commission judges the evidence that treating hearing loss lowers dementia risk to be stronger than before.
None of this research treated tinnitus. ACHIEVE and the observational studies were about hearing loss.
What this means if you have tinnitus
- Get your hearing tested. Hearing loss commonly comes with tinnitus, it is the part of the picture with an established dementia link, and it can be treated. What a first audiology appointment involves describes the tests, and how tinnitus is diagnosed sets out the wider workup.
- Treat hearing loss for its own sake. Hearing aids often help tinnitus that comes with hearing loss, and the Commission recommends they be accessible to people with hearing loss. Buying them as dementia prevention goes further than ACHIEVE supports.
- Protect the hearing you have. In the 2025 UK Biobank study, more than 5 years of noise exposure carried a hazard ratio for dementia of 1.12 (95% CI 1.00 to 1.26), and the Commission recommends reducing harmful noise. Noise-induced tinnitus covers prevention.
- If tinnitus bothers you, treat the distress. Distress, more than the sound, tracked poorer thinking scores in the study of 107 people above, and it responds to treatment such as CBT for tinnitus. The treatment comparison sets the options side by side.
- Keep the absolute numbers in view. Even in the Taiwanese cohort that found a link, 3.1% of people with tinnitus were diagnosed with Alzheimer's disease during follow-up, so almost 97% were not.
Some early dementia symptoms the NHS lists, such as difficulty concentrating and struggling to follow a conversation, overlap with what tinnitus and hearing loss can do, which is one more reason not to diagnose yourself. The NHS stresses that dementia is not a natural part of ageing and advises talking to a GP sooner rather than later if you are worried about memory problems or other symptoms. For tinnitus symptoms that need prompt attention, such as sudden hearing loss or tinnitus in only one ear that persists, the when to seek care checker sets out how quickly to be seen.