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In addition, some studies suggest that wearing hearing aids may help prevent dementia, though one study was recently voluntarily retracted due to methodological errors.
Given the overall evidence, how robust are these associations? And what guidance should clinicians provide to their patients?
Frank Lin, MD, PhD, a clinician and professor of otolaryngology and epidemiology at Johns Hopkins University School of Medicine, Baltimore, emphasized that the evidence from the past 10-15 years strongly links hearing loss to cognitive decline.
While quantifying the exact increase in risk is challenging, Dr. Lin said, “there’s no doubt about it; it’s not trivial.”
With respect to the potential link between hearing aids and dementia prevention, Dr. Lin is involved in the ongoing ACHIEVE randomized trial. Results presented at the 2023 Alzheimer’s Association International Conference and simultaneously published in The Lancet revealed participants who used hearing aids experienced a significant slowing of cognitive decline compared with those who received health education.
“It’s a no-risk intervention that can benefit social function, and for people at risk for cognitive decline, it can actually benefit cognitive health,” Dr. Lin said.
Potential Mechanisms
Dr. Lin pointed out that the Lancet Commission on Dementia identifies hearing impairment as one of the most significant risk factors for dementia. Overall, the consensus from most studies is that hearing loss definitely increases the risk for cognitive decline and dementia, he said.
Several hypotheses may explain this connection, and Dr. Lin believes that a combination of three key mechanisms is likely to be central to understanding this link.
The first theory focuses on cognitive load. As people experience age-related hearing changes, “the inner ear is no longer sending signals clearly to the brain,” Dr. Lin explained. This forces the brain to work harder, increasing its cognitive load as it reallocates resources to assist with hearing.
Dr. Lin emphasized that this is a hypothesis and does not prove hearing loss directly causes cognitive decline or dementia. Rather, it suggests that hearing loss accelerates the “unmasking” of cognitive issues. Brain resources that might otherwise buffer against dementia’s pathologic triggers are consumed earlier due to the demands of managing hearing loss.
The second potential mechanism suggests that hearing loss may have detrimental effects on brain structure and function over time — a theory supported by several recent studies.
These studies show that individuals with more severe hearing loss experience faster rates of brain atrophy. The reduced stimulation from poor auditory signals accelerates brain atrophy, Dr. Lin explained.
The third hypothesis focuses on social isolation. Individuals with hearing loss may engage less in social activities, reducing cognitive stimulation and overall social interaction. It’s well-known that social engagement and cognitive stimulation are crucial for maintaining cognitive health over time, Dr. Lin said.
Overall, Dr. Lin believes that the association between hearing loss and an increased risk for cognitive decline likely involves a combination of all three potential mechanisms. It’s not a matter of one theory being right and the others being wrong, he said.
The Role of Hearing Aids
However, the jury is out on the role of hearing aids in preventing dementia.
A large observational study published in 2023 in Lancet Public Health was hailed by its investigators as providing “the best evidence to date” that hearing aids could mitigate the impact of hearing loss on dementia (Lancet Public Health. 2023 May;8[5]:e329-e338. doi: 10.1016/S2468-2667[23]00048-8). However, the authors voluntarily retracted the paper in December 2023 due to a coding error.
Despite this, a large meta-analysis published in JAMA Neurology suggested that hearing aids might reduce cognitive decline and dementia risk and even enhance short-term cognitive function.
Additionally, the ACHIEVE study, the first randomized trial to investigate these issues, included nearly 1000 older participants from two populations — those from the ARIC study and healthy volunteers. Participants were randomly assigned to receive either a hearing intervention or education on healthy aging.
Although the primary endpoint of change in standardized neurocognitive scores at year 3 showed no significant difference between the hearing intervention and health education groups, the ARIC cohort experienced a notable 48% reduction in cognitive decline with hearing aids compared with education.
Dr. Lin explained that, due to the study’s design, the control group was healthier than the ARIC cohort, which was at higher risk for cognitive decline due to factors such as age and diabetes. This is where they observed a strong effect of hearing intervention in reducing cognitive decline within just 3 years, Dr. Lin said.
Conversely, the hearing aids had minimal impact on the healthy controls, likely because they had not experienced cognitive decline to begin with. Essentially, the benefits of hearing aids were more apparent once cognitive issues were already present.
“It seems sort of obvious. In a group of people who aren’t at risk for cognitive decline, a hearing intervention isn’t going to benefit their cognition” in the short term, Dr. Lin noted. That said, the investigators are continuing to follow the healthy controls to determine whether hearing aids lower dementia risk over the long term.
Which Comes First?
Some experts have questioned the directionality of the link between hearing aids and dementia — do hearing aids reduce dementia risk or are individuals with dementia simply less likely to use them?
Dr. Lin noted that observational studies often have confounders. For instance, people who use hearing aids are often healthier and better educated. This makes it difficult to distinguish the effect of the intervention from the factors that led people to use it, he said.
In contrast, the ACHIEVE trial, a randomized study, was designed to separate these factors from the hearing intervention, Dr. Lin explained.
However, he added that ACHIEVE was not specifically powered to assess dementia development, focusing instead on cognitive decline. The investigators plan long-term follow-up of participants to evaluate the impact on dementia in the future.
So, given the current evidence, what should clinicians tell their patients?
Because all people experience some degree of hearing changes as they age, which can gradually affect communication and social engagement, it’s important for everyone to be aware of their hearing health, Dr. Lin said.
He noted there are apps available that allow individuals to measure their hearing with their phones, including determining their “hearing number.”
With respect to hearing aids, Dr. Lin noted that if individuals have trouble participating in everyday activities, addressing hearing issues and considering a hearing intervention is crucial.
There’s no medical risk associated with hearing aids, he said. Even if they only improve social activities and engagement, that’s a benefit. If they also have potential positive effects on cognitive health, “even better,” he added.
Dr. Lin noted that as of 2022, hearing aids are now available over the counter, a move that has improved accessibility. In addition, new technologies, such as stylish “hearing aid glasses,” are being developed to offer more appealing options and reduce the stigma associated with traditional devices.
People often view hearing loss as a significant life event and are reluctant to admit they need hearing aids. However, focusing on “what’s your hearing?” as a neutral tracking metric could make it easier to adopt new technologies in the future, Lin said.
Alzheimer’s Association Weighs in
Heather Snyder, PhD, vice president, Medical & Scientific Relations at the Alzheimer’s Association, echoed Dr. Lin, noting that there has been substantial research showing a link between hearing loss and cognitive decline.
“This association is something that we have seen repeated and replicated in a number of different studies. What we don’t know is the cause and effect,” Dr. Snyder said.
She noted it is unknown whether there is a causal link between hearing loss and cognitive decline and/or whether cognitive decline may contribute to hearing loss. These are some of the “big questions” that remain, said Dr. Snyder.
Still, she noted that hearing health is an important part of quality of life and overall brain health and “should be part of the conversation” between clinicians and their patients.
Discussing the results of the ACHIEVE study, Dr. Snyder highlighted that while the subgroup at higher risk for cognitive decline did experience significant improvement, the overall population did not show a benefit from the intervention.
The brain “is complex,” and it’s unlikely that a single intervention or target will provide all the benefits, Dr. Snyder said.
She emphasized that addressing hearing loss with hearing aids, combined with managing other modifiable risk factors — such as heart and metabolic health, physical activity, and a balanced diet — appears to offer the greatest potential for synergy and preserving cognition.
Drs. Lin and Snyder reported no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.
In addition, some studies suggest that wearing hearing aids may help prevent dementia, though one study was recently voluntarily retracted due to methodological errors.
Given the overall evidence, how robust are these associations? And what guidance should clinicians provide to their patients?
Frank Lin, MD, PhD, a clinician and professor of otolaryngology and epidemiology at Johns Hopkins University School of Medicine, Baltimore, emphasized that the evidence from the past 10-15 years strongly links hearing loss to cognitive decline.
While quantifying the exact increase in risk is challenging, Dr. Lin said, “there’s no doubt about it; it’s not trivial.”
With respect to the potential link between hearing aids and dementia prevention, Dr. Lin is involved in the ongoing ACHIEVE randomized trial. Results presented at the 2023 Alzheimer’s Association International Conference and simultaneously published in The Lancet revealed participants who used hearing aids experienced a significant slowing of cognitive decline compared with those who received health education.
“It’s a no-risk intervention that can benefit social function, and for people at risk for cognitive decline, it can actually benefit cognitive health,” Dr. Lin said.
Potential Mechanisms
Dr. Lin pointed out that the Lancet Commission on Dementia identifies hearing impairment as one of the most significant risk factors for dementia. Overall, the consensus from most studies is that hearing loss definitely increases the risk for cognitive decline and dementia, he said.
Several hypotheses may explain this connection, and Dr. Lin believes that a combination of three key mechanisms is likely to be central to understanding this link.
The first theory focuses on cognitive load. As people experience age-related hearing changes, “the inner ear is no longer sending signals clearly to the brain,” Dr. Lin explained. This forces the brain to work harder, increasing its cognitive load as it reallocates resources to assist with hearing.
Dr. Lin emphasized that this is a hypothesis and does not prove hearing loss directly causes cognitive decline or dementia. Rather, it suggests that hearing loss accelerates the “unmasking” of cognitive issues. Brain resources that might otherwise buffer against dementia’s pathologic triggers are consumed earlier due to the demands of managing hearing loss.
The second potential mechanism suggests that hearing loss may have detrimental effects on brain structure and function over time — a theory supported by several recent studies.
These studies show that individuals with more severe hearing loss experience faster rates of brain atrophy. The reduced stimulation from poor auditory signals accelerates brain atrophy, Dr. Lin explained.
The third hypothesis focuses on social isolation. Individuals with hearing loss may engage less in social activities, reducing cognitive stimulation and overall social interaction. It’s well-known that social engagement and cognitive stimulation are crucial for maintaining cognitive health over time, Dr. Lin said.
Overall, Dr. Lin believes that the association between hearing loss and an increased risk for cognitive decline likely involves a combination of all three potential mechanisms. It’s not a matter of one theory being right and the others being wrong, he said.
The Role of Hearing Aids
However, the jury is out on the role of hearing aids in preventing dementia.
A large observational study published in 2023 in Lancet Public Health was hailed by its investigators as providing “the best evidence to date” that hearing aids could mitigate the impact of hearing loss on dementia (Lancet Public Health. 2023 May;8[5]:e329-e338. doi: 10.1016/S2468-2667[23]00048-8). However, the authors voluntarily retracted the paper in December 2023 due to a coding error.
Despite this, a large meta-analysis published in JAMA Neurology suggested that hearing aids might reduce cognitive decline and dementia risk and even enhance short-term cognitive function.
Additionally, the ACHIEVE study, the first randomized trial to investigate these issues, included nearly 1000 older participants from two populations — those from the ARIC study and healthy volunteers. Participants were randomly assigned to receive either a hearing intervention or education on healthy aging.
Although the primary endpoint of change in standardized neurocognitive scores at year 3 showed no significant difference between the hearing intervention and health education groups, the ARIC cohort experienced a notable 48% reduction in cognitive decline with hearing aids compared with education.
Dr. Lin explained that, due to the study’s design, the control group was healthier than the ARIC cohort, which was at higher risk for cognitive decline due to factors such as age and diabetes. This is where they observed a strong effect of hearing intervention in reducing cognitive decline within just 3 years, Dr. Lin said.
Conversely, the hearing aids had minimal impact on the healthy controls, likely because they had not experienced cognitive decline to begin with. Essentially, the benefits of hearing aids were more apparent once cognitive issues were already present.
“It seems sort of obvious. In a group of people who aren’t at risk for cognitive decline, a hearing intervention isn’t going to benefit their cognition” in the short term, Dr. Lin noted. That said, the investigators are continuing to follow the healthy controls to determine whether hearing aids lower dementia risk over the long term.
Which Comes First?
Some experts have questioned the directionality of the link between hearing aids and dementia — do hearing aids reduce dementia risk or are individuals with dementia simply less likely to use them?
Dr. Lin noted that observational studies often have confounders. For instance, people who use hearing aids are often healthier and better educated. This makes it difficult to distinguish the effect of the intervention from the factors that led people to use it, he said.
In contrast, the ACHIEVE trial, a randomized study, was designed to separate these factors from the hearing intervention, Dr. Lin explained.
However, he added that ACHIEVE was not specifically powered to assess dementia development, focusing instead on cognitive decline. The investigators plan long-term follow-up of participants to evaluate the impact on dementia in the future.
So, given the current evidence, what should clinicians tell their patients?
Because all people experience some degree of hearing changes as they age, which can gradually affect communication and social engagement, it’s important for everyone to be aware of their hearing health, Dr. Lin said.
He noted there are apps available that allow individuals to measure their hearing with their phones, including determining their “hearing number.”
With respect to hearing aids, Dr. Lin noted that if individuals have trouble participating in everyday activities, addressing hearing issues and considering a hearing intervention is crucial.
There’s no medical risk associated with hearing aids, he said. Even if they only improve social activities and engagement, that’s a benefit. If they also have potential positive effects on cognitive health, “even better,” he added.
Dr. Lin noted that as of 2022, hearing aids are now available over the counter, a move that has improved accessibility. In addition, new technologies, such as stylish “hearing aid glasses,” are being developed to offer more appealing options and reduce the stigma associated with traditional devices.
People often view hearing loss as a significant life event and are reluctant to admit they need hearing aids. However, focusing on “what’s your hearing?” as a neutral tracking metric could make it easier to adopt new technologies in the future, Lin said.
Alzheimer’s Association Weighs in
Heather Snyder, PhD, vice president, Medical & Scientific Relations at the Alzheimer’s Association, echoed Dr. Lin, noting that there has been substantial research showing a link between hearing loss and cognitive decline.
“This association is something that we have seen repeated and replicated in a number of different studies. What we don’t know is the cause and effect,” Dr. Snyder said.
She noted it is unknown whether there is a causal link between hearing loss and cognitive decline and/or whether cognitive decline may contribute to hearing loss. These are some of the “big questions” that remain, said Dr. Snyder.
Still, she noted that hearing health is an important part of quality of life and overall brain health and “should be part of the conversation” between clinicians and their patients.
Discussing the results of the ACHIEVE study, Dr. Snyder highlighted that while the subgroup at higher risk for cognitive decline did experience significant improvement, the overall population did not show a benefit from the intervention.
The brain “is complex,” and it’s unlikely that a single intervention or target will provide all the benefits, Dr. Snyder said.
She emphasized that addressing hearing loss with hearing aids, combined with managing other modifiable risk factors — such as heart and metabolic health, physical activity, and a balanced diet — appears to offer the greatest potential for synergy and preserving cognition.
Drs. Lin and Snyder reported no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.
In addition, some studies suggest that wearing hearing aids may help prevent dementia, though one study was recently voluntarily retracted due to methodological errors.
Given the overall evidence, how robust are these associations? And what guidance should clinicians provide to their patients?
Frank Lin, MD, PhD, a clinician and professor of otolaryngology and epidemiology at Johns Hopkins University School of Medicine, Baltimore, emphasized that the evidence from the past 10-15 years strongly links hearing loss to cognitive decline.
While quantifying the exact increase in risk is challenging, Dr. Lin said, “there’s no doubt about it; it’s not trivial.”
With respect to the potential link between hearing aids and dementia prevention, Dr. Lin is involved in the ongoing ACHIEVE randomized trial. Results presented at the 2023 Alzheimer’s Association International Conference and simultaneously published in The Lancet revealed participants who used hearing aids experienced a significant slowing of cognitive decline compared with those who received health education.
“It’s a no-risk intervention that can benefit social function, and for people at risk for cognitive decline, it can actually benefit cognitive health,” Dr. Lin said.
Potential Mechanisms
Dr. Lin pointed out that the Lancet Commission on Dementia identifies hearing impairment as one of the most significant risk factors for dementia. Overall, the consensus from most studies is that hearing loss definitely increases the risk for cognitive decline and dementia, he said.
Several hypotheses may explain this connection, and Dr. Lin believes that a combination of three key mechanisms is likely to be central to understanding this link.
The first theory focuses on cognitive load. As people experience age-related hearing changes, “the inner ear is no longer sending signals clearly to the brain,” Dr. Lin explained. This forces the brain to work harder, increasing its cognitive load as it reallocates resources to assist with hearing.
Dr. Lin emphasized that this is a hypothesis and does not prove hearing loss directly causes cognitive decline or dementia. Rather, it suggests that hearing loss accelerates the “unmasking” of cognitive issues. Brain resources that might otherwise buffer against dementia’s pathologic triggers are consumed earlier due to the demands of managing hearing loss.
The second potential mechanism suggests that hearing loss may have detrimental effects on brain structure and function over time — a theory supported by several recent studies.
These studies show that individuals with more severe hearing loss experience faster rates of brain atrophy. The reduced stimulation from poor auditory signals accelerates brain atrophy, Dr. Lin explained.
The third hypothesis focuses on social isolation. Individuals with hearing loss may engage less in social activities, reducing cognitive stimulation and overall social interaction. It’s well-known that social engagement and cognitive stimulation are crucial for maintaining cognitive health over time, Dr. Lin said.
Overall, Dr. Lin believes that the association between hearing loss and an increased risk for cognitive decline likely involves a combination of all three potential mechanisms. It’s not a matter of one theory being right and the others being wrong, he said.
The Role of Hearing Aids
However, the jury is out on the role of hearing aids in preventing dementia.
A large observational study published in 2023 in Lancet Public Health was hailed by its investigators as providing “the best evidence to date” that hearing aids could mitigate the impact of hearing loss on dementia (Lancet Public Health. 2023 May;8[5]:e329-e338. doi: 10.1016/S2468-2667[23]00048-8). However, the authors voluntarily retracted the paper in December 2023 due to a coding error.
Despite this, a large meta-analysis published in JAMA Neurology suggested that hearing aids might reduce cognitive decline and dementia risk and even enhance short-term cognitive function.
Additionally, the ACHIEVE study, the first randomized trial to investigate these issues, included nearly 1000 older participants from two populations — those from the ARIC study and healthy volunteers. Participants were randomly assigned to receive either a hearing intervention or education on healthy aging.
Although the primary endpoint of change in standardized neurocognitive scores at year 3 showed no significant difference between the hearing intervention and health education groups, the ARIC cohort experienced a notable 48% reduction in cognitive decline with hearing aids compared with education.
Dr. Lin explained that, due to the study’s design, the control group was healthier than the ARIC cohort, which was at higher risk for cognitive decline due to factors such as age and diabetes. This is where they observed a strong effect of hearing intervention in reducing cognitive decline within just 3 years, Dr. Lin said.
Conversely, the hearing aids had minimal impact on the healthy controls, likely because they had not experienced cognitive decline to begin with. Essentially, the benefits of hearing aids were more apparent once cognitive issues were already present.
“It seems sort of obvious. In a group of people who aren’t at risk for cognitive decline, a hearing intervention isn’t going to benefit their cognition” in the short term, Dr. Lin noted. That said, the investigators are continuing to follow the healthy controls to determine whether hearing aids lower dementia risk over the long term.
Which Comes First?
Some experts have questioned the directionality of the link between hearing aids and dementia — do hearing aids reduce dementia risk or are individuals with dementia simply less likely to use them?
Dr. Lin noted that observational studies often have confounders. For instance, people who use hearing aids are often healthier and better educated. This makes it difficult to distinguish the effect of the intervention from the factors that led people to use it, he said.
In contrast, the ACHIEVE trial, a randomized study, was designed to separate these factors from the hearing intervention, Dr. Lin explained.
However, he added that ACHIEVE was not specifically powered to assess dementia development, focusing instead on cognitive decline. The investigators plan long-term follow-up of participants to evaluate the impact on dementia in the future.
So, given the current evidence, what should clinicians tell their patients?
Because all people experience some degree of hearing changes as they age, which can gradually affect communication and social engagement, it’s important for everyone to be aware of their hearing health, Dr. Lin said.
He noted there are apps available that allow individuals to measure their hearing with their phones, including determining their “hearing number.”
With respect to hearing aids, Dr. Lin noted that if individuals have trouble participating in everyday activities, addressing hearing issues and considering a hearing intervention is crucial.
There’s no medical risk associated with hearing aids, he said. Even if they only improve social activities and engagement, that’s a benefit. If they also have potential positive effects on cognitive health, “even better,” he added.
Dr. Lin noted that as of 2022, hearing aids are now available over the counter, a move that has improved accessibility. In addition, new technologies, such as stylish “hearing aid glasses,” are being developed to offer more appealing options and reduce the stigma associated with traditional devices.
People often view hearing loss as a significant life event and are reluctant to admit they need hearing aids. However, focusing on “what’s your hearing?” as a neutral tracking metric could make it easier to adopt new technologies in the future, Lin said.
Alzheimer’s Association Weighs in
Heather Snyder, PhD, vice president, Medical & Scientific Relations at the Alzheimer’s Association, echoed Dr. Lin, noting that there has been substantial research showing a link between hearing loss and cognitive decline.
“This association is something that we have seen repeated and replicated in a number of different studies. What we don’t know is the cause and effect,” Dr. Snyder said.
She noted it is unknown whether there is a causal link between hearing loss and cognitive decline and/or whether cognitive decline may contribute to hearing loss. These are some of the “big questions” that remain, said Dr. Snyder.
Still, she noted that hearing health is an important part of quality of life and overall brain health and “should be part of the conversation” between clinicians and their patients.
Discussing the results of the ACHIEVE study, Dr. Snyder highlighted that while the subgroup at higher risk for cognitive decline did experience significant improvement, the overall population did not show a benefit from the intervention.
The brain “is complex,” and it’s unlikely that a single intervention or target will provide all the benefits, Dr. Snyder said.
She emphasized that addressing hearing loss with hearing aids, combined with managing other modifiable risk factors — such as heart and metabolic health, physical activity, and a balanced diet — appears to offer the greatest potential for synergy and preserving cognition.
Drs. Lin and Snyder reported no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.