Research Gives Urgency to Treating Hearing Loss
Studies Show Possible Link to Accelerated Brain Tissue Loss + Dementia
Brain shrinkage seems to be fast-tracked in older adults with hearing loss, according to the results of a study by researchers from Johns Hopkins and the National Institute on Aging. The findings add to a growing list of health consequences associated with hearing loss.
This study compounds research collected from a previous study (by the same group), released in February 2011, that showed seniors with hearing loss are significantly more likely to develop dementia over time than those who retain their hearing.
The report states that although the reason for the link between the two conditions is unknown, the investigators suggest that a common pathology may underlie both or that the strain of decoding sounds over the years may overwhelm the brains of people with hearing loss, leaving them more vulnerable to dementia. They also speculate that hearing loss could lead to dementia by making individuals more socially isolated, a known risk factor for dementia and other cognitive disorders.
The report also states that whatever the cause, their finding may offer a starting point for interventions — even as simple as hearing aids — that could delay or prevent dementia by improving patients’ hearing.
Solutions at Pindrop
“We see the profound effect hearings aids have on our patients every day,” said Doctor of Audiology, David Patterson, Au.D., R.Aud, Aud(c) and Director of Audiology for Pindrop Hearing Centres across Canada. “This study provides information on possible health consequences associated with hearing loss, including dementia and brain shrinkage.”
To assist patients across Canada, Pindrop Hearing Centres delivers solutions that make it easier on the brain. Oticon Opn BrainHearing™ Technology, delivers 30% better speech understanding* and 20% less listening effort* so users remember 20% more**
“Oticon Opn™ is the first hearing aid proven to make it easier on the brain,” said Patterson. “Testing consistently shows that Oticon Opn increases speech understanding, the parameter most important to users, by 30% over other Oticon hearing solutions. Oticon Opn users experienced 20% less listening effort when trying to understand speech. Additional studies show that because Oticon Opn users have freed up brain capacity, they are able to remember 20% more of what was said.”
As a result of this and other leading research, “we are continually educating our patients about the connection between hearing, hearing solutions and cognition,” said Patterson.
Brain Tissue Loss
This most recent study regarding brain tissue loss, released in January 2014, was also completed by Frank Lin, M.D., Ph.D., at Johns Hopkins and the National Institute on aging. He and his colleagues used information from the ongoing Baltimore Longitudinal Study of Aging to compare brain changes over time between adults with normal hearing and adults with impaired hearing. The Baltimore Longitudinal Study of Aging was started in 1958 by the National Institute on Aging to track various health factors in thousands of men and women.
The report states previous research from other studies had linked hearing loss with marked differences in brain structure compared to those with normal hearing, both in humans and animals. In particular, structures that process information from sound tended to be smaller in size in people and animals with impaired hearing. Frank Lin, M.D., Ph.D., an assistant professor at the Johns Hopkins University schools of medicine and public health, says it was unknown, however, whether these brain structural differences occurred before or after hearing loss.
As part of the Baltimore Longitudinal Study of Aging, 126 participants underwent yearly magnetic resonance imaging (MRI) to track brain changes for up to 10 years. After analyzing their MRIs over the following years, Lin and his colleagues, reported participants whose hearing was already impaired at the start of the sub-study had accelerated rates of brain atrophy compared to those with normal hearing.
Overall, the scientists report, those with impaired hearing lost more than an additional cubic centimeter of brain tissue each year compared with those with normal hearing. Those with impaired hearing also had significantly more shrinkage in particular regions, including brain structures responsible for processing sound and speech.
However, according to Dr. Lin, these structures don’t work in isolation, and their responsibilities don’t end at sorting out sounds and language. The middle and inferior temporal gyri, for example, also play roles in memory and sensory integration and have been shown to be involved in the early stages of mild cognitive impairment and Alzheimer’s disease. “Our results suggest that hearing loss could be another ‘hit’ on the brain in many ways,” Lin explains.
The study also gives some urgency to treating hearing loss rather than ignoring it. “If you want to address hearing loss well,” Lin says, “you want to do it sooner rather than later. If hearing loss is potentially contributing to these differences we’re seeing on MRI, you want to treat it before these brain structural changes take place.”
To see the full results of each study please see:
For more information about BrainHearing Solutions please contact Pindrop Hearing Centres.