Hearing
Loss Linked to Dementia and Alzheimer’s Disease
On
April 7, 1989, in the 261 volume of The
Journal of the American Medical Association,
five American scientists published a paper “Relationship
of Hearing Impairment to Dementia and Cognitive Dysfunction in Older
Adults“.
The authors demonstrated an association between hearing impairment
and dementia. Since then, more research in this area has been
conducted at numerous leading US and world universities. More
recently, the relationship between a hearing impairment and
Alzheimer's disease has been confirmed. The February 14, 2011
bulletin by the AARP (American Association of Retired Persons)
carried the article by Elizabeth Agnvall “Hearing Loss Linked to
Dementia. Even a mild hearing loss doubles the risk “. Excerpt
reads:
“Adults
with hearing loss are significantly more likely than adults with
normal hearing to
develop
dementia, according to a new study out today from researchers at
John's Hopkins and the National Institute on Aging. The study --
which finds the greater the hearing loss, the higher the risk – may
open a new avenue of research into dementia and Alzheimer's disease.
Man
and woman in the study who experienced severe hearing loss were five
times more likely to develop dementia than those with normal hearing.
But even mild hearing loss doubled the risk of dementia.”
A
new study published in the February 2011 issue of ARCHIVES
OF NEUROLOGY
(Vol. 68) confirmed what a lot of physicians who deal with hearing
loss and dementia had suspected before: adults with hearing loss have
a greater chance of developing dementia, and this risk increases as
their hearing impairment worsens.
“This
work suggests that there is a strong predictive association between
hearing loss as an adult and the likelihood of developing cognitive
decline with aging.”
According
to study lead author Dr. Luigi Ferrucci, Chief of the U.S. National
Institute on Aging Longitudinal Studies Section. The “COMMENT“
part of this paper states as follows:
“In
this study, hearing loss was independently associated with all-cause
dementia after adjustment for sex, age, race, education, diabetes,
smoking, and hypertension, and our findings were robust to multiple
sensitivity analyses. The risk of all-cause dementia increased log
linearly with hearing loss severity, and for individuals older than
60 years in our cohort, more
than one third of the risk of incident all cause dementia was
associated with hearing loss.”
“According
to several major studies, older adults with hearing loss are more
likely to develop Alzheimer's
disease and dementia, compared to those with normal hearing. Further,
the risk escalates,
as person's hearing loss grows worse. Those with mild hearing
impairment are nearly
twice as likely to develop dementia compared to those with normal
hearing. The risk increases three-fold for those with moderate
hearing loss, and five-fold for those with severe impairment.“
And
also:
“In
response to these findings, further studies found that hearing aids
can delay, or prevent, dementia and Alzheimer's disease by improving
patients' hearing. Further, treating hearing loss with hearing aids
can reduce many Alzheimer's symptoms for people with the disease.”
Should
you require more information, we will be happy to provide people
interested in this area of research with copies of the papers,
articles, used for this issue of our newsletter as well as any new
studies results published.
Alicja
and Janusz Tobola from Metro Hearing Clinic Mississauga and
Scarborough
905
273 7717