Article summary
People with hearing loss who used devices such as hearing aids and cochlear implants had a 19% lower risk of long-term cognitive decline and a 3% improvement in short-term general cognition test scores.
A new meta-analysis published online Dec. 5 found that individuals who used hearing aids and cochlear implants for hearing loss had a reduced risk of cognitive decline. Department of Neurology, JAMA.
Researchers found that using these hearing aids was significantly associated with a 19% lower risk of long-term cognitive decline and a 3% improvement in short-term general cognition test scores. I discovered that
“Hearing loss is recognized as the greatest modifiable risk factor for dementia, accounting for 8% of dementia cases. Neurology Today.
“However, it remained unclear prior to our study whether treatment of hearing loss could prevent dementia,” Dr. Tan added. After years of research, there is still no cure and prevention is the best weapon.”
A meta-analysis by Dr. Tan and his collaborators included observational studies of randomized clinical trials and peer-reviewed journals on the effects of hearing interventions on cognitive function, cognitive decline, cognitive impairment, and dementia in patients with hearing loss. It was
Other studies have shown that hearing aids may prevent accidental cognitive impairment by correcting hearing loss. Several observational studies suggest that hearing aids may reduce the onset of dementia. However, not all observational studies have shown benefits from hearing aid use, and “may be due to inconsistent wearing of hearing aids in social situations or delayed implementation of these hearing aids.” There is,” the authors wrote.
They said: Some studies may have insufficient sample sizes, so a pooled analysis may help increase statistical power. Their study therefore aimed to “analyze both cognitive scores and longitudinal data to determine long-term associations between hearing restoration devices and cognitive impairment and incidental dementia.” bottom.
The strengths of this meta-analysis include a rigorous systematic search and a large number of studies from around the world, said Dr. Tan, making the findings more generalizable. Neurology TodayHowever, “based on the available data, we were unable to determine whether the severity of hearing loss affects the potential cognitive benefits obtained from using hearing aids,” he said. , cited this as a limitation of the study.
Nonetheless, it was encouraging that even patients who started with mild cognitive impairment in the pooled analysis benefited from hearing aid use, as their risk of progressing to dementia was approximately 20% lower.
“This means it’s never too late to start using hearing aids,” he said.
Dr. Tang and his colleagues recommended that clinicians consider performing a hearing assessment for all new patients with early-stage dementia and as part of regular health screenings for older adults. . It’s easy, fast, harmless and cheap.
“All neurologists, geriatricians, psychiatrists, otolaryngologists, and family physicians should strongly recommend hearing aids or cochlear implants for patients with hearing loss.
Methodology and results
The analysis included studies from the PubMed, Embase and Cochrane databases (to 23 July 2021), focusing on the effects of hearing interventions on cognitive decline and dementia in people with hearing loss.
A total of 3243 studies were screened for this review, including 31 studies (25 observational studies and 6 trials) involving 137,484 participants, of which 19 studies (15 observational and 4 trials) were included in the quantitative analysis.
In a meta-analysis of eight studies with a total of 126,903 participants, follow-up ranged from 2 to 25 years. We assessed the long-term association between hearing aid use and cognitive decline and showed that hearing aid users had a significantly lower risk of cognitive decline compared to participants with uncorrected hearing loss (HR , 0.81).
Another meta-analysis of 11 studies with a total of 568 participants examined the association between hearing recovery and changes in short-term cognitive test scores and found a 3% improvement in short-term cognitive test scores after hearing aid use. (mean ratio, 1.03). ).
Expert commentary
Accompanying editorial Department of Neurology, JAMA He said the meta-analysis underscored the wealth of evidence supporting an association between hearing loss and cognitive decline/dementia.
While researchers await the results of randomized clinical trials, the editorial authors recommend that “physicians consider hearing assessments part of the standard dementia work-up.”
Justin S. Golub, MD, MS, lead author of the editorial, recently noted that hearing loss is recognized as one of the greatest potentially modifiable risk factors for dementia.
This study is one of the highest quality reviews looking at the relationship between hearing interventions and the prevention of dementia/dementia symptoms, said Otolaryngology – Head and Neck Surgery Otology, Neurology, and Skull Base Surgery. Associate Professor Dr. Golub said. Columbia University Bagueros College of Physicians and Surgeons and New York Presbyterian/Columbia University Irving Medical Center.
Dr. Golub said the meta-analysis is more powerful than a single survey, with included studies coming from multiple geographic regions around the world. The study also adjusted for confounding variables, he said.
“The field is at a crossroads where randomized controlled trials are needed,” he said, noting that the study did not include high-quality randomized controlled trials. Only such trials can establish a definitive causal link between hearing loss and cognitive decline/dementia.
Dr. Golub pointed out that hearing loss is largely ignored among healthcare professionals other than otolaryngologists and audiologists. Unlike many other medical treatments, hearing aids have few risks.
Noting that over-the-counter hearing aids will become available in the fall, Dr. Golub said, “I hope this research will encourage people to use these wonderful, more affordable devices.” said.
Hearing restoration techniques (hearing aids and cochlear implants) should be recommended for patients with bilateral hearing loss, even when one ear is significantly worse than the other, says Terry D. Fife, MD , FAAN, FANS, oto- Director Director of Neurology and Balance Disorders and Graduate Medical Education at the Barrow Institute of Neurology, Phoenix, Arizona.
“The results of this study support the idea that hearing aids and cochlear implants may offer more than just enjoyment in improving hearing,” he said, adding that these devices could “maintain cognitive health.” It may also offer additional benefits for
However, “hearing aids are often not covered by insurance because they are not considered essential medical devices, they are considered luxuries,” says Dr. Fife, who is also a professor of neurology at the University of Arizona School of Medicine. says. Phoenix.
“Hearing from both ears is fused in the brain into a unified perception, which is important for quality of life, engagement in social interactions, and delayed or diminished cognitive function,” said Dr. Fife. .”
He added that binaural hearing improves language comprehension. Sounds that are barely audible in one ear 10 feet away are much more audible in both ears up to 40 feet away. The directional localization of sound sources is also improved in bilateral hearing, reducing hearing “deprivation” and reducing and improving hearing loss in situations with background noise.
“The brain is wired to hear from both ears, enhancing social interaction and cognitive stimulation,” said Dr. Phife. “Studies show that hearing loss is associated with cognitive impairment, and hearing improvement reverses the effects of cognitive decline in patients with functionally significant hearing loss.”
Dr. Fife pointed out that the current meta-analysis has some limitations. “Definitions of hearing loss severity and clear educational level were limited,” he said. “We did not have enough data to understand how important hearing loss is and whether people without cognitive impairment at baseline would lose ground without improvement in hearing quality.”
A major missing point in these published papers was that the treatment of hearing loss results from returning an audible signal across input levels and frequencies, says Catherine V. Palmer, Ph.D. University of Pittsburgh.
This occurs when an audiologist measures the output of a hearing aid in the user’s ear and adjusts the device based on the measured characteristics of the individual’s hearing and ear canal, affecting the amount of sound delivered to the ear. “By simply focusing on the ‘device,’ the authors imply that any device will regain audibility, but that is not the case,” she said.
Dr. Palmer, who is also chair of the Department of Audiology at the University of Pittsburgh Medical Center, said: As such, future studies should describe hearing aid fitting and resulting audibility in order to actually evaluate treatments on cognition. Knowing someone has an amplifier is not enough to interpret the research. ”
Still, Dr. Palmer said, “These findings from the meta-analysis provide a compelling argument for referral of patients with concerns about cognitive decline for auditory assessment and treatment.” Given that it reduced the risk of cognitive decline.”
Disclosure:
Dr. Golub receives consulting fees from Alcon. Doctor.Tan, Fife and Palmer had no disclosures.