Does hearing loss raise the risk of dementia, and do hearing aids help?
Answered November 2, 202612 sources
EvidenceDPreliminaryVery uncertain: animal or cell studies, or studies in people with several serious weaknesses.
Hearing loss is linked to a higher chance of dementia, roughly one and a third times as high. Whether hearing aids lower that risk is unproven, because the main trial found no benefit overall.
Who it's for
Anyone with hearing loss may want it treated; dementia protection isn't shown.
What to expect
Hearing aids did not slow thinking decline over 3 years in the main trial.
Watch out for
Links in observational studies may reflect other factors, not cause and effect.
Hearing loss goes with a higher chance of dementia
Each dot is a pooled result with a line for its range, and a value above 1 means higher risk than normal hearing.
← BetterWorse →
No difference
Dementia1.35 (1.26 to 1.45)Clear worsening
Mild cognitive impairment1.29 (1.11 to 1.5)Clear worsening
Alzheimer's disease1.56 (1.3 to 1.87)Clear worsening
Vascular dementia1.3 (0.83 to 2.05)No clear difference
11.52
risk of dementia vs. normal hearing, 1 = same
Hearing loss goes with a higher chance of dementia
A clinical practice guideline for age-related hearing loss strongly recommends that clinicians offer properly fitted hearing aids to patients with this condition7Guideline · 2024Clinical Practice Guideline: Age-Related Hearing Loss.It is… PURPOSE: The purpose of this clinical practice guideline is to identify quality improvement opportunities and provide clinicians trustworthy, evidence-based… ACTION STATEMENTS: The GDG made strong recommendations for the following key action statements (KASs): (KAS 4) If screening suggests hearing loss,…Otolaryngol Head Neck Surg. It doesn't base that advice on dementia prevention in the excerpt available.
What the studies show
A review that pooled 50 studies following about 1.5 million adults found hearing loss linked to a 35% higher relative risk How much more or less likely something is in one group than another, as a ratio. A big relative change can still be a small change for any one person. of dementia. Each 10-decibel worsening of hearing was linked to a 16% higher risk4Meta-analysis · 2024 · 1,548,754 peopleAdult-onset hearing loss and incident cognitive impairment and dementia - A systematic review and meta-analysis of cohort studies.Cohort studies consistently support that adult-onset hearing loss increases the risk of incident cognitive decline, dementia, MCI, and ADD.Ageing Res Rev. Other reviews found similar links, with 49% to 59% higher relative risk5Meta-analysis · 2018 · 37,898 peopleHearing loss and the risk of dementia in later life.This is an important finding, particularly in light of recent suggestions that mid-life hearing loss may account for up to 9. 1% of dementia cases worldwide, and efforts to reduce its impact should continue to be explored.Maturitas,6Meta-analysis · 2021 · 726,900 peopleHearing Loss and Dementia: A Meta-Analysis of Prospective Cohort Studies.Hearing loss may increase the risk of dementia in the adult population. Whether effective treatment for hearing loss could reduce the incidence of dementia should be explored in the future.Front Aging Neurosci. These figures compare groups, so the gain for one person depends on their starting risk.
The strongest test of hearing aids is a randomized trial People are assigned by chance to the treatment or a comparison, so a difference in results is likely caused by the treatment itself. of 977 adults aged 70 to 84 with untreated hearing loss. After 3 years, thinking decline was the same with a hearing intervention as with health education3Randomized trial · 2023 · 3,004 peopleHearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE): a multicentre, randomised controlled trial.The hearing intervention did not reduce 3-year cognitive decline in the primary analysis of the total cohort. However, a prespecified sensitivity analysis showed that the effect differed between the two study populations that comprised the cohort. These findings suggest that a hearing intervention might reduce…Lancet.
That trial's two groups differed. The effect may have varied between participants at higher risk of decline and those at lower risk. This was a sensitivity analysis, so it is a hint, not a result3Randomized trial · 2023 · 3,004 peopleHearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE): a multicentre, randomised controlled trial.The hearing intervention did not reduce 3-year cognitive decline in the primary analysis of the total cohort. However, a prespecified sensitivity analysis showed that the effect differed between the two study populations that comprised the cohort. These findings suggest that a hearing intervention might reduce…Lancet.
A review of mostly observational Studies that watch what happens to people rather than assigning a treatment. They can show links, not cause and effect. studies found hearing aid users had a 19% lower relative risk of long-term thinking decline than people with untreated hearing loss. Short-term test scores were about 3% better2Meta-analysis · 2023 · 903 peopleAssociation of Hearing Aids and Cochlear Implants With Cognitive Decline and Dementia: A Systematic Review and Meta-analysis.In this meta-analysis, the usage of hearing restorative devices by participants with hearing loss was associated with a 19% decrease in hazards of long-term cognitive decline. Furthermore, usage of these devices was significantly associated with a 3% improvement in cognitive test scores that assessed general cognition…JAMA Neurol. Healthier people may be more likely to use aids, which can explain this.
A Danish study of 573,088 people found dementia risk was 20% higher in untreated hearing loss, against 6% higher in aid users, compared with normal hearing. Both figures are small and observational8Observational study · 2024 · 88 peopleHearing Loss, Hearing Aid Use, and Risk of Dementia in Older Adults.The results of this cohort study suggest that hearing loss was associated with increased dementia risk, especially among people not using hearing aids, suggesting that hearing aids might prevent or delay the onset and progression of dementia. The risk estimates were lower than in previous studies, highlighting the…JAMA Otolaryngol Head Neck Surg.
Smaller studies also link hearing loss to dementia9Observational study · 2011 · 639 peopleHearing loss and incident dementia.Hearing loss is independently associated with incident all-cause dementia. Whether hearing loss is a marker for early-stage dementia or is actually a modifiable risk factor for dementia deserves further study.Arch Neurol,10Observational study · 2017Hearing Impairment and Incident Dementia and Cognitive Decline in Older Adults: The Health ABC Study.HI is associated with increased risk of developing dementia in older adults. Randomized trials are needed to determine whether treatment of hearing loss could postpone dementia onset in older adults.J Gerontol A Biol Sci Med Sci. Hearing loss could also be an early sign of dementia rather than a cause9Observational study · 2011 · 639 peopleHearing loss and incident dementia.Hearing loss is independently associated with incident all-cause dementia. Whether hearing loss is a marker for early-stage dementia or is actually a modifiable risk factor for dementia deserves further study.Arch Neurol.
Key studies
Study
Who
What it found
Review of 50 cohort studies Researchers follow a group of people over time without giving them a treatment. It can show links, not cause and effect., 20244Meta-analysis · 2024 · 1,548,754 peopleAdult-onset hearing loss and incident cognitive impairment and dementia - A systematic review and meta-analysis of cohort studies.Cohort studies consistently support that adult-onset hearing loss increases the risk of incident cognitive decline, dementia, MCI, and ADD.Ageing Res Rev
About 1.5 million adults
Hearing loss linked to 35% higher dementia risk
Trial, 20233Randomized trial · 2023 · 3,004 peopleHearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE): a multicentre, randomised controlled trial.The hearing intervention did not reduce 3-year cognitive decline in the primary analysis of the total cohort. However, a prespecified sensitivity analysis showed that the effect differed between the two study populations that comprised the cohort. These findings suggest that a hearing intervention might reduce…Lancet
977 adults aged 70 to 84
No difference in 3-year thinking decline overall
Review of observational studies and trials, 20232Meta-analysis · 2023 · 903 peopleAssociation of Hearing Aids and Cochlear Implants With Cognitive Decline and Dementia: A Systematic Review and Meta-analysis.In this meta-analysis, the usage of hearing restorative devices by participants with hearing loss was associated with a 19% decrease in hazards of long-term cognitive decline. Furthermore, usage of these devices was significantly associated with a 3% improvement in cognitive test scores that assessed general cognition…JAMA Neurol
Adults with hearing loss
Hearing aid use linked to 19% lower decline risk
Study following people, 20248Observational study · 2024 · 88 peopleHearing Loss, Hearing Aid Use, and Risk of Dementia in Older Adults.The results of this cohort study suggest that hearing loss was associated with increased dementia risk, especially among people not using hearing aids, suggesting that hearing aids might prevent or delay the onset and progression of dementia. The risk estimates were lower than in previous studies, highlighting the…JAMA Otolaryngol Head Neck Surg
573,088 Danish adults
Dementia risk higher without hearing aids than with them
Safety
No significant side effects attributed to the hearing intervention were reported in the main trial3Randomized trial · 2023 · 3,004 peopleHearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE): a multicentre, randomised controlled trial.The hearing intervention did not reduce 3-year cognitive decline in the primary analysis of the total cohort. However, a prespecified sensitivity analysis showed that the effect differed between the two study populations that comprised the cohort. These findings suggest that a hearing intervention might reduce…Lancet.
What we don't know
Whether treating hearing loss lowers dementia risk. The main trial ran only 3 years, and dementia develops over many more.
Whether people at higher risk of decline benefit more. Trials are under way11Registered trial · 2024Early Age-Related Hearing Loss Investigation (EARHLI)ClinicalTrials.gov.
Written by AI from the studies listed, without review by a clinician, and graded with the GRADE method. It can be wrong, so check the studies it cites. Education, not medical advice.