Troublesome Duo: Alzheimer
’s Disease and Hearing Loss
Julie Eckhardt, M.A., L.P.C
Michigan Association for Deaf and Hard of Hearing
“I am worried about my mother,” the 50-something woman explained to the social worker. “She used to be
active and alert. Now she is withdrawn and anxious. When we all get together, she sits back and barely says a
word. When someone asks her a question she either stares blankly or answers something so off the wall… And
she seems really depressed. I
’m afraid we are losing her. Do you think she has Alzheimer’s?”
While no professional would make a diagnosis based on this information alone, there is growing evidence that
the woman in question could be misdiagnosed as having dementia, or that the severity of her condition would
be misinterpreted or exacerbated due to untreated hearing loss.
The number of people in North America over 65 years of age is skyrocketing. According to the U.S. Census
Bureau, 12.6 percent of North American citizens were over 65 in the year 2000. The percentage is expected to
be 14.9 percent by 2015, and 20.3 percent by 2030.i As the population ages, so does the incidence of age related
conditions such as Alzheimer
’s Disease (AD) and hearing loss. According to Chartrand, there is a strikingsimilarity between the age distribution of those with AD and those with hearing loss.ii There is also a shocking
similarity in symptoms. Unfortunately, this correlation is widely overlooked by medical practitioners.
There are three reasons why this issue needs to be addressed by those who work with a geriatric population.
These reasons will be outlined, and then elaborated upon in this brief article.
1. The early symptoms of late onset Alzheimer’s disease are very similar to the symptoms of untreated
hearing loss.
2. Commonly used dementia screening instruments are administered verbally and assume normal hearing
acuity and central auditory processing. Untreated hearing loss may result in a misdiagnosis.
3. Evidence suggests that untreated hearing loss may contribute to cognitive dysfunction, and that treating
hearing loss may reduce the symptoms of dementia.
Similarity of Symptoms
In the following chart, courtesy of Max Stanley Chartrand, Ph.D., the symptoms of late onset Alzheimer’s
Disease are compared to the symptoms of untreated hearing loss:
Alzheimer
’s Disease Untreated Hearing Loss
Depression, anxiety, disorientation Depression, anxiety, social isolation
Reduced language compr ehension Reduced speech discr imination
Impaired memory (esp. short-term) Reduced cognitive input into memory
Inappropriate psychosocial responses Inappropriate psychosocial responses
Loss of recognition (agnosia) Reduced mental scor es (cognitive dysfunction)
Denial, defensiveness, negativi ty Denial, defensiveness, negativi ty
Distrust, suspicious of other
’s motives Distrust, paranoia (belief that others are talking about them)
Because there tends to be much more fear about the symptoms of dementia, hearing loss is often overlooked as
a common consequence of aging and not adequately addressed. This oversight can be devastating to the person
with hearing loss. People with hearing loss often find communication to be so difficult that they simply
withdraw from interaction and activities, leading to isolation and depression. People with hearing loss may
appear to be out of touch with reality when they do not accurately hear the topic of question and answer
inappropriately. In a study of normal elderly volunteers, it was discovered that the presence of hearing
impairment increased the effort required to recognize speech. This level of effort reduced the mental reserve for
rehearsal and later recall.
iii Hearing loss induced recall difficulties may be misdiagnosed as dementia.
Screening for Dementia
The Mini Mental State Examination (MMSE), the Sternberg Memory Scan and California Verbal Learning Test
use a series of verbal (spoken) questions for administration.iv Even more in-depth instruments such as the
WAIS-R rely heavily upon verbal directions. These measures all assume normal hearing and auditory
processing and are routinely administered without a prior audiological assessment. This is in spite of the fact
that 1 in 3 people over 65 years of age has a hearing loss.v As reported in an article by Amanda Nichols, “When
furnished with hearing amplification, residents with dementia score better on cognitive screening tests than
those without amplification.”vi The risk of misclassification of the severity of senile dementia in people with
undetected hearing loss has been well documented
vii and could have devastating affects on a person’s life.
Treating Hearing Loss to Reduce Symptoms of Dementia
According to an article in the Journal of the American Medical Association, severity of hearing loss correlates
significantly with the level of cognitive decline in older adults, even after consideration of variables such as
depression, medication, and age. The researchers concluded that the results of the case-control study of 100
people with Alzheimer’s-type dementia, “demonstrates an association between hearing impairment and
dementia and lends support to the hypothesis that hearing impairment contributes to cognitive dysfunction in
older adults.
viii
After discovering that 83% of a sample of institutionalized patients with a diagnosis of senile dementia had
hearing loss that exceeded 25 dB, the patients were retested for dementia while using an auditory trainer for
amplification.ix Ten of the subjects (33%) were reclassified to a less severe category of dementia.
In a study on the effects of improving hearing on dementia, researchers found that nearly half of the mildly
hearing impaired subjects with dementia improved when hearing loss was treated.x Furthermore, these
researchers found that patients with dementia could benefit from hearing aids and tolerated audiological
procedures well.
Conclusion
Screening for and treating hearing loss can have a profound impact on the cognitive functioning and quality of
life of elderly people. Even those already diagnosed with dementia may benefit significantly from the use of
amplification. Screening tools such as the Hearing Handicap Inventory for the Elderly may be used to determine
if assessment by a licensed audiologist is in order. Even low cost assistive listening devices (such as the
Pocketalker for about $150.00) may provide improved comprehension and more accurate diagnosis for a person
with hearing loss.
i Kinsella, K. and Vokoff, V. An Aging World: 2001. U.S. Census Bureau Report.
ii
Chartrand, M. The Absence of Hearing Healthcare in a so-called “Tidal Wave of Alzhimer’s Cases.” AudiologyOnline 2002. Available at: www.audiologyonline.comiii Allen, N., Burns, A., Newton, V., Hickson, F., Ramsden, R., Rogers, J., Butler, S., Thistlewaite, G., Morris, J. The effects of improving hearing in dementia. Age and
Ageing 2003:32:189-193
iv
Chartrand, M. Undiagnosed Pre-Existing Hearing Loss in Alzheimer’s Disease Patients? HealthyHearing 2005. Available at www.healthyhearing.com
v
Facts on Hearing Loss. Distributed by the Hearing Loss Association of America: www.hearingloss.org
vi
Nichols, A. Hearing Loss: Perceptions and Solutions. Nursing Homes Long Term Care Management: 2006. Available at www.nursinghomesmagazine.com
referencing a study by Weinstein, B. E., Amsel, L. Hearing loss and senile dementia in the Institutionalized elderly. Clinical Gerontologist 1986:4:3-15.
vii
Newman, D. and Sandridge, S. Hearing Loss is often undiscovered but screening is easy. Cleveland Clinic Journal of Medicine 2004:71:3:225-232.viii Uhlmann, R., Larson El., Rees T., Koepsell, T., DuckertL Relationship of hearing impairment to dementia and cognitive dysfunction in older adults. JAMA 1989;
161:1916-1919.
ix
Dancer, J. Watkins, P. Remember Me? A Guide to Alzheimer’s Disease and Hearing Loss. HealthyHearing.com: 2005. Available at www.healthyhearing.com
x
Allen, N., et al 2003.