By Max S. Chartrand
From the archives of Hearing Health Magazine:
Alzheimer's is predicted to afflict almost epidemic proportions of the elderly in the coming decades, yet the medical community in general still ignores the cognitive and health impact of unmitigated hearing loss.
Alzheimer's Tidal Wave A Hearing Connection?
There's a tidal wave coming all right – the exponential growth of an aging population. Since risk of developing Alzheimer's disease (AD) increases with age, it has the potential to become the epidemic of the new century. Worldwide, the number of people with AD is projected to increase to 22 million by 2025 and 45 million by 2050.
Making matters worse, mental processing difficulties among older adults are so strongly identified with AD that many seniors are either unaware or in deep denial about the most pervasive forces behind cognitive disconnection: hearing loss and central auditory processing disorders.
When considering the mental health of the elderly, the measurement of hearing and auditory deficits is sorely neglected. Instead, these should be explored before other possible contributing factors to perceived problems with mental processing. Unfortunately, without these considerations, the feared cognitive disconnect will become self-fulfilling reality.
The Demographics of Aging
An alarming increase in the number of people living past the age of 65 in the U.S. is imminent. This is the age where most AD cases occur. Further, in the 85+ age group, an even greater demographic advance will be seen.
Matching the growth of these age groups with increased incidence of hearing loss, we find startling parallels between uncorrected hearing loss and the number of clinically suspected cases of AD.
Because the symptoms of uncorrected hearing loss mimic outward behavior characteristics of early onset Alzheimer's, only a team that includes hearing and mental health professionals would be able to ascertain overlay components.
The predicted increase of AD also tracks the aging of America. In 1999 there were 36 million people over age 65 in the U.S., 4.2 million of whom were diagnosed with AD. By 2020, 52 million people will be over 65, with 8.9 million AD cases.
Lack of Professional Awareness
Hearing impairment among the AD population is twice that of the non-AD population, when matched for age and gender. This has been found in study after study. Yet fewer than 10 percent of hearing-impaired AD patients utilize amplification, compared to six in 10 hearing-impaired persons in the non-AD population. This means that those who most need aural rehabilitation tend to be the least likely to receive it.
Substantial professional and institutional barriers prevent people with AD and hearing loss from receiving hearing care. Among them are:
- Lack of medical referral
- Difficult-to-test stereotype
- Lack of effective data
- Inappropriate diagnosis and technology
- Lack of access to ongoing care
Public Awareness
Only four percent of people with mild hearing loss use hearing aids. Few are aware that they have an impairment because they typically respond normally to the low-frequency vowel sounds of speech. High-frequency consonants, however, present more problems, particularly in noise or at distances. Professionals tend to underrate mild impairments, not realizing that this is where a marked cognitive disconnect begins in the older adult.
Still more tragic is the fact that in the moderate loss ranges, only 36 percent are using hearing technology. People in this category often find their lives dramatically altered through broken social bonds, reduced vocational and personal aspirations and, in many cases, depression, hypertension and underlying anxiety. Far too many are treated pharmacologically rather than receiving aural rehabilitation.
But the real tragedy is that only 54 percent of people with severe and profound hearing impairment in the U.S. utilize hearing aids, cochlear implants, and assistive devices. For the remaining 46 percent, lack of public and professional awareness of recent technological and clinical advancements has fostered dependence upon society and prevented achievement of their true potential.
The Devil is in the Details
A 1996 study at the University of South Florida found that 49 of 52 elderly persons diagnosed with memory disorders also had unmitigated severe hearing loss (called "serious hearing loss" in the study).
Their conclusion:
"Undiagnosed hearing loss interferes with learning, and makes people seem distracted, confused, disoriented and unresponsive, traits that might suggest Alzheimer's disease."
Other studies of elderly patients with uncorrected hearing loss indicate "feelings of helplessness, depression, passivity, and negativism." Rapid and accelerated decline in various dementias were found due to uncorrected hearing loss in older adults. Social isolation and depression are found in yet other studies too numerous to cite here.
Hearing deficits, when uncorrected, can exacerbate memory and cognitive disorders. For instance, the memory pathways of the brain allow one to remember at the end of a sentence what was said at the beginning, a mental acrobatic feat that only humans can perform.
Putting Aural Rehab into the Picture
Nursing and administrative personnel who care for the majority of AD cases in institutions for the elderly claim that nearly all of their patients suffer from dementias of various etiologies. When queried about hearing aid use in their facilities, most respond that a few of their patients have hearing aids.
Upon closer examination, however, it is found that the "few" really don't benefit from their instruments because of dead batteries, wax in the receivers or inappropriate control settings. "It's just too much trouble to keep up with," comes the refrain of those who most often must spend their finite resources regulating medication, meals and basic life care. Yet most individuals with AD would be on fewer medications, enjoy more independence in daily activities and, most of all, lead happier, more productive lives if their hearing health were on par with their other health needs.
Allow me to propose a more logical and effective pathway in the clinical protocols during the early stages of symptoms that point to AD and other dementias:
Individuals come first to their primary physician because of attentional and/or mild memory problems. The doctor performs the appropriate physical to exclude obvious physical/pharmacological contributors.
Physician refers the patient to a hearing health professional for a full hearing and speech evaluation. If a hearing loss is detected, treatment with hearing aids and aural rehabilitation is instituted.
If cognitive symptoms persist after a 90-day interval of aural rehabilitation, the patient is referred to a mental or neurological health professional trained in diagnosing and treating dementia.
The mental health professional refers the patient for nutritional analysis and counseling in tandem with the work of the other professionals.
Perhaps a speech-language pathologist is also indicated for treatment of possible perceptive or expressive aphasia, central auditory processing or other communicative problems. The services of a geriatrician or occupational therapist might also be warranted and enlisted.
Through a team approach, these professionals then work together for the benefit of the patient, recognizing the important contribution each will make in the rehabilitative process.
Conclusion
Hearing and mental health are intricately interconnected. The sense of "hearing" actually occurs in the brain, not the periphery apparatus. Hearing requires normal communication function in the brain in order to process appropriately. Likewise, in order for the human brain to function normally, good hearing health is required.
There is a glaring oversight in today's clinical and medical model when diagnosing and treating AD. The most pervasive sensory filter of all, the vital sense of hearing, is totally ignored in current protocols. Meanwhile, billions of dollars are wasted, uncountable hours of medical resources squandered and millions of lives are held hostage. Needlessly so.
