Sensory Changes   5  

Pamela Z. Cacchione

OVERVIEW

Understanding how to assess for and manage sensory deficits is essential to holistic nursing. A goal of Healthy People 2020 is to decrease the prevalence and severity of disorders of vision, hearing, balance, smell, and taste, as well as voice, speech, and language (USDHHS, 2010). This chapter on sensory changes addresses common age-related changes associated with the senses as well as disease states and injuries to the senses that occur more commonly with aging. Nursing care related to the Healthy People 2020 goals regarding sensory changes are also addressed.

BACKGROUND AND STATEMENT OF PROBLEM

Individuals experience and interact with their environments through their senses. Vision, hearing, smell, taste, and peripheral sensation allow us to safely experience and enjoy the world around us. Changes in sensory function (vision, hearing, smell, taste, and peripheral sensation) are common as people age. These sensory changes can negatively impact the older adult’s ability to interact with his or her environment, decreasing quality of life. For example, changes in hearing can impact an older person’s communication skills; changes in vision can impact his or her health literacy by limiting the ability to take medications safely. Researchers have determined that sensory impairment is more dangerous than previously thought (Cacchione, 2014). More recent, sensory impairment, particularly vision and hearing impairment, has been linked to increased mortality (Cugati et al., 2007; Gopinath et al., 2013; Karpa et al., 2010). Healthy People 2020 emphasizes the importance of healthy senses, including vision, hearing, balance, smell, and taste. Vision and hearing abilities are essential to language, whether spoken, signed, or read (U.S. Department of Health and Human Services [USDHHS], 2010). Decreases in sense of smell can interfere with an older adult’s ability to smell smoke in a fire or recognize spoiled food. Many adults report a decrease in taste that impacts their desire to eat. Decreased peripheral sensation sets up an individual for falls.

NORMAL CHANGES OF AGING SENSES

The senses—vision, hearing, taste, smell, balance, and peripheral sensation—change with aging, usually presenting primarily with a slowing of function. A summary table is presented describing the changes that occur and the functional outcomes for each sense (Table 5.1).

Vision

There are several changes that occur with vision as people age. The eyelids start lagging, potentially obscuring vision; the pupil takes longer to dilate and contract, slowing accommodation; and presbyopia is widespread.

Presbyopia

A loss of elasticity in the lens and stiffening of the muscle fibers of the lens of the eye leads to a decrease in the eyes’ ability to change the shape of the lens to focus on near objects, such as fine print, and decreases ability to adapt to light (National Eye Institute [NEI], 2010; Whiteside, Wallhagen, & Pettengill, 2006).

Hearing

Normal changes of aging impacting hearing acuity include the decrease in function of the hair fibers in the ear canal that normally aid in the natural removal of cerumen and the protection of the ear canal from external elements. Conduction of sound is limited by the ossification of the stapes, decreasing the vibration of the stapes and thickening of the tympanic membrane making it less flexible (Wallhagen, Pettengill, & Whiteside, 2006).

TABLE 5.1

Normal Changes of Aging

Adapted from Bromley (2000); Linton (2007); Murphy et al. (2002); Schiffman (1997); Seiberling and Conley (2004); Wallhagen et al. (2006); Whiteside et al. (2006).

Presbycusis

Presbycusis is the most common form of hearing loss in the United States (Bagai, Thavendiranathan, & Detsky, 2006). This high-frequency sensorineural hearing loss is a multifactorial process that varies in severity and is associated with aging (Gates & Mills, 2005). Presbycusis usually has a bilateral progressive onset and is caused by gradual loss of hair cells and fibrous changes in the small blood vessels that supply the cochlea. Risk factors include heredity, environmental exposure, free radicals, and mitochondrial deoxyribonucleic acid (DNA) damage (Huang & Tang, 2010). Clinical presenting symptoms of this irreversible condition include high-frequency hearing loss and difficulty hearing high-pitched sounds such as /t/, /p/, /k/, /s/, /z/, /sh/, and /ch/ (Huang & Tang, 2010; Wallhagen, Strawbridge, Shema, & Kaplan, 2004). Background noise further aggravates this hearing deficit.

Smell

Changes in smell are common as we age, but are not considered a normal part of aging. Frequently, older adults complain of distortions of smell. Factors associated with loss of sense of smell include age and gender, with older males being more prone to smell loss (Hoffman, Cruickshanks, & Davis, 2009). The environment, trauma, diseases, or illness can diminish the sense of smell (Hoffman et al., 2009). Changes in the sense of smell have also been found to correlate with neurological conditions, such as Parkinson’s disease, and genetically with Alzheimer’s disease (Albers, Tabert, & Devanand, 2006; Oleson & Murphy, 2015; Wilson, Arnold, Schneider, Tang, & Bennett, 2007).

Taste

Common changes in taste include a decreased ability to detect the intensity of taste but not somatic sensations, such as touch and burning pain in the tongue, when compared with younger adults (Fukunaga, Uematsu, & Sugimoto, 2005). However, complete loss of taste is rare and changes in taste are more often related to dental concerns; diseases or illness, such as rhinitis, allergies, or infections; and medications or cancer treatments to the head and neck (Fukunaga et al., 2005; Hoffman et al., 2009).

Peripheral Sensation

Peripheral nerve function that controls the sense of touch declines slightly with age. Two-point discrimination and vibratory sense both decrease with age. The ability to perceive painful stimuli is preserved in aging. However, there may be a slowed reaction time for pulling away from painful stimuli with aging (Linton, 2007).

ASSESSMENT OF THE PROBLEM

Vision

The prevalence of visual impairment increases with age and the settings in which older adults live, with vision impairment affecting approximately 2.6 million adults older than 65 years in the United States (Prevent Blindness America, 2012). According to data from the National Health and Nutrition Examination Survey (NHANES; Dillon, Gu, Hoffman, & Ko, 2010; Schiller, Lucas, & Peregoy, 2012; Swenor, Ramulu, Willis, Friedman, & Lin, 2013), in older adults aged 70 to 79 years, 3.4%, and in older adults 80 years and older, 15.9% were found to be visually impaired (Swenor et al., 2013), but this varied by race and ethnicity with non-Hispanic Whites (13.8%), non-Hispanic Blacks (21.1%), and Mexican Americans (24%). Additionally, a study investigating socioeconomic factors in vision found that increasing age and lower socioeconomic status were associated with vision impairment (Zheng et al., 2012). Adults aged 80 years and older accounted for 7.7% of one study’s participants but were 69% of the cases of blindness (Congdon et al., 2004). This is worrisome because this is the fastest growing segment of our population.

Studies evaluating older adults in long-term care settings demonstrate prevalence rates of visual impairment from 27% to 57% of older adults (Bron & Caird, 1997; Cacchione, Culp, Dyck, & Laing, 2003; Swanson, McGwin, Elliott, & Owsley, 2009). Uncorrected refractive error was also found to be common in visually impaired older adults. In one study, of the 8.8% of the older adults found to be visually impaired, 59% were impaired because of an uncorrected refractive error (Vitale, Cotch, & Sperduto, 2006). Leading causes of blindness by race and ethnicity were found to be macular degeneration in Whites, cataracts and open-angle glaucoma in Blacks, and open-angle glaucoma in Hispanic persons (Congdon et al., 2004). Cataracts, one of the leading causes of blindness, are unilateral or bilateral clouding of the crystalline lens that presents as painless, progressive loss of vision (NEI, 2009).

The definition of visual impairment varies by different groups and by country (Agency for Healthcare Research and Quality [AHRQ], 2004). The United States defines low vision as best corrected visual acuity:

Low vision can also be defined based on visual field limitations. Severe visual impairment is defined as best corrected field less than or equal to 20° (legal blindness). Profound visual impairment is defined as visual field less than or equal to 10 degrees (AHRQ, 2004).

Nursing Assessment of Vision

The health history is an essential part of vision assessment. Several health conditions predispose older adults to visual impairment. In the United States, diabetes is a common cause of disease-related blindness associated with diabetic retinopathy, with 40% to 45% of diabetics having some stage of diabetic retinopathy (NEI, 2015b). Hypertension carries with it the risk of hypertensive retinopathy. Ascertaining a thorough baseline health history with yearly reviews and updates is essential in maintaining visual health. Health questions related to visual health include the questions shown in Table 5.2 (Cacchione, 2007; Wallhagen et al., 2006).

Examination of the Eye

The external structures can cause decreased vision if the lids lag because of laxity of the skin of the upper eyelid. Lid lag can interfere with visual acuity and fields, which may require surgery. A decreased level of tear function can negatively impact visual acuity. In severe cases, cataracts can be visible with the naked eye and appear as a whitish gray pupil instead of black. Cloudiness of the whole cornea of the eye is indicative of a corneal problem, not a cataract. If the person has had cataract surgery, the lens implant may be visible on close inspection.

TABLE 5.2

Vision History Questions

Adapted from Cacchione (2007); Whiteside et al. (2006).

Fundus Exam. Using an ophthalmoscope, a nurse can visualize the red reflex and, with experience and practice, the fundus of the eye. This is often difficult with small pupils. Darkening the room may help with dilating the pupils. Optometrists and ophthalmologists dilate the pupils to allow for a better view of the fundus. Cataracts will appear as a dark shadow in the anterior portion of the lens in front of the retina.

Vision Testing. Vision testing should be completed before the eyes are dilated and assessed in each eye, then both eyes together for both uncorrected and corrected (with glasses) vision.

Distance Vision. The “gold standard” in eye charts, the Snellen chart, is one of the most commonly used to assess distance vision. Visual acuity is tested at 20 feet. The individual is asked to read the letters on the chart until he or she misses more than two on a line of acuity. Acuity equals the line above the line with more than two errors. Acuity measures range from 20/10 to 20/800 on the Snellen chart.

Early Treatment Diabetic Retinopathy Study. The Early Treatment Diabetic Retinopathy Study (ETDRS; Ferris, Kassoff, Bresnick, & Bailey, 1982) eye chart is also used frequently and can be used at a distance of 4 meters. At this distance, the greatest visual acuity measured is 20/200—the equivalent of legal blindness.

Pin-Hole Test. With best vision, with or without glasses, a card with a small pin hole or a multiple pin-hole occluder can be placed in front of the eye, and the vision is tested again at the last line the individual was able to read. This test identifies refractive error of the peripheral cornea of the lens of the eye by allowing only perpendicular light into the lens (Kalinowski, 2008). If the individual can read farther down the chart with the pin hole, his or her vision may be improved with better refraction of his or her eyeglasses or, if he or she does not have glasses, vision could be improved with eyeglasses.

Near Vision. Near vision is important for health literacy, especially regarding reading food or medication labels. There are several ways to assess near vision. Two commonly used tools are the Rosenbaum Pocket Eye Screener and the Lighthouse for the Blind Near Vision Screener. The Rosenbaum Pocket Eye Screener is a noncopyrighted tool based on the Snellen chart that can be useful in assessing near vision in the acute care and primary care settings. The Rosenbaum is true to scale when compared with the Snellen chart at the 20/200, 20/400, and 20/800 acuity levels. However, the other levels are slightly too large, causing an overestimation of visual acuity (Horton & Jones, 1997).

Lighthouse for the Blind Near Vision Screener (Lighthouse for the Blind). This handheld vision screener has a cord that can be used at 40 and 20 centimeters to measure the proper distance for testing near vision. This near vision screener mimics the ETDRS eye chart in a smaller version but is not pocket size. It does not, however, have the concern over the scale matching of the ETDRS distance acuity level. For research purposes, it has the added feature of the cord for measuring a consistent distance.

Contrast Sensitivity. Contrast sensitivity is often compromised by aging and diseases or conditions of the eye. Decreases in contrast sensitivity occur with cataracts, glaucoma, and retinopathies (Mäntyjärvi & Laitinen, 2001; Owsley, 2011). Contrast sensitivity provides information on how well an individual may perform in real-life conditions. Decline in contrast sensitivity impacts one’s ability to distinguish when one step ends and another begins, identify light switches on the wall, read materials not made in high-contrast font, or identify the buttons on the remote. Intact contrast sensitivity is important for day-to-day safety and function within the environment. Impaired contrast sensitivity has been associated with falls, decreased physical function, and nursing home placement in older adults (Swanson et al., 2009).

The Pelli–Robson Contrast Sensitivity Chart (Pelli, Robson, & Wilkins, 1988) is read at the 1- or 3-meter distance. All letters are presented at the 20/200 acuity level but in decreasing shades of black to gray. The Pelli–Robson Contrast Sensitivity Chart is widely used in practice and works well for older adults who are experienced in recognizing letters (Hirvelä & Laatikainen, 1995; Morse & Rosenthal, 1997). The Vistech Contrast Sensitivity Test, another contrast sensitivity measure, has four patches of gray circles with lines in different directions (Kennedy & Dunlap, 1990). The person being examined points to the direction in which the lines within the circle are pointed (Morse & Rosenthal, 1997).

Visual Fields. Fields of vision refers to the area of peripheral vision visible when the individual is focusing straight ahead (Cassin & Rubin, 2001). The vision in visual fields can be affected by many eye conditions, specifically glaucoma, macular degeneration, and retinopathies (Jessa, Evans, Thomson, & Rowlands, 2007), as well as neurological disorders that inhibit eye movement or affect the blood supply to the optic nerve. Intact visual fields are necessary to function safely in one’s environment. In assessing visual fields by confrontation, a gross clinical measure of visual fields, the examiner faces the patient and determines whether the patient can identify the examiner’s moving fingers as they are moving into their field of view (Seidel, Dains, Ball, & Benedict, 2003). Although subjective and dependent on the examiner having normal fields of vision, the confrontation test is useful in quickly identifying large losses in visual fields.

The Humphrey Visual Field Test is completed by an ophthalmologist and assesses visual fields using a static type of perimetry (Gianutsos & Suchoff, 1997). This instrument provides a more reliable measure of functional visual fields. The Goldman VI4e kinetic perimetry visual field testing, on the other hand, assesses kinetic type of functional visual fields (Gillmore, 2002). Kinetic perimetry entails the introduction of a moving stimulus, moving from a nonvisible area toward the fixed point of view. The Goldman VI4e kinetic perimetry visual field testing is hard to standardize because it is operator dependent (Gillmore, 2002). Because these automated methods are more widely used, the location of the visual field deficit may clue the examiner about the type of eye condition. For example, unilateral visual field deficits may be related to a cerebral vascular accident, glaucoma will affect the peripheral fields, and macular degeneration has associated loss of central field of vision.

Stereopsis. Stereopsis is the process in which humans have the ability to use the different viewpoints provided by their eyes to produce a vivid perception of depth and three-dimensional shapes (Norman et al., 2008; Read, Phillipson, Serrano-Pedraza, Milner, & Parker, 2010). There are multiple methods of measuring stereopsis and it is not thought to be affected by aging but may be negatively impacted by distance acuity and eye diseases (Norman et al., 2008).

Visual Function Questionnaire

The NEI Visual Function Questionnaire (VFQ-25) is a 25-item survey that assesses the functional impact of visual impairment. It provides a subjective report on 12 functional subscales: general vision, near vision, distance vision, driving, peripheral vision, color vision, ocular pain, general health, vision-specific role difficulties, dependency, social function, and mental health (Revicki, Rentz, Harnam, Thomas, & Lanzetta, 2010). The NEI VFQ-25 has sound psychometric properties in cognitively intact older adults (Mangione et al., 2001).

Conditions of the Eye

Diseases That Alter Vision Seen More Frequently as People Age

Cataracts. Cataracts are clouding of the crystalline lens that presents either unilaterally or bilaterally as painless, progressive loss of vision (NEI, 2009). Cataracts are usually age related but they can be secondary to glaucoma, diabetes, Alzheimer’s disease; congenital; injury related; or related to medications or sunlight exposure (NEI, 2009). The management of cataracts includes early identification and monitoring followed by surgical extraction and lens implantation once vision is affected.

Macular Degeneration. This involves the development of drusen deposits in the retinal pigmented epithelium and is the leading cause of central vision loss and legal blindness in older adults (Revicki et al., 2010). Macular degeneration is more common in fair-haired, blue-eyed individuals. Other risk factors include smoking and excessive sunlight exposure. There are wet and dry forms of macular degeneration. The wet form of macular degeneration is more easily treated than the dry form. Newer treatments of expensive injectable medications are available to slow the progression of dry macular degeneration (NEI, 2015a).

Glaucoma. Glaucoma is a progressive, serious form of eye disease that can damage the optic nerve and result in vision loss and blindness (NEI, 2014). Primary open-angle glaucoma is the most common form of glaucoma in older adults (Linton, 2007). Increased intraocular pressure causes atrophy and cupping of the optic nerve head, which leads to visual field deficits that can progress to blindness. Vision changes include loss of peripheral vision, intolerance to glare, decreased perception of contrast, and decreased ability to adapt to the dark. Treatments are available to delay vision loss, but no cure is available. Glaucoma is the leading cause of blindness all over the world (NEI, 2014). African Americans and Mexican Americans are five times more likely to develop glaucoma (NEI, 2014).

Diabetic Retinopathy. This results from end-organ damage from diabetes causing retinopathy and spotty vision. The risk can be reduced by tight blood sugar control. Almost 9% of diabetics older than 65 years develop diabetic retinopathy (Prevent Blindness America, 2012). Diabetic retinopathy starts as mild nonproliferative retinopathy with microaneurysms on the retina and progresses as moderate to severe nonproliferative retinopathy in which blood vessels in the retina are blocked, depriving the retina of adequate blood supply, then progresses to proliferative retinopathy in which the growth of new abnormal fragile blood vessels that leak can cause blindness (NEI, 2012).

Hypertensive Retinopathy. Similar to diabetic retinopathy, hypertensive retinopathy is caused by end-organ damage from poorly controlled hypertension causing background and, eventually, proliferative retinopathy. Hypertensive retinopathy is usually treated with laser photocoagulation and tight blood pressure control.

Temporal Arteritis. This is an autoimmune disorder that causes inflammation of the temporal artery, also known as giant cell arteritis. It presents as malaise, scalp tenderness, unilateral temporal headache, jaw claudication, and sudden vision loss (usually unilateral). This vision loss is a medical emergency but is potentially reversible if identified immediately. The client should see an ophthalmologist or go to the emergency room immediately if symptoms develop.

Detached Retina. This is a condition that can occur in patients with cataracts or recent cataract surgery, trauma, or it can occur spontaneously. A detached retina presents as a curtain coming down across a patient’s line of vision. An individual experiencing this should see an ophthalmologist or proceed to the closest emergency room immediately. See Table 5.3 for implications of vision changes on an older adult’s function.

TABLE 5.3

Implications of Vision Changes in Older Adults

INTERVENTIONS AND CARE STRATEGIES

Vision

The nurse should obtain a past medical history to avoid disruption in the management of chronic eye conditions, ensuring continuation of ongoing regimens, such as eye drops for glaucoma. Without the continuation of the individual’s eye drops, eye pressures could precipitously increase causing an acute exacerbation of the glaucoma, potentially dramatically limiting vision. If an acute change in an individual’s vision occurs, the primary care provider should be notified immediately. Depending on the signs and symptoms present, the individual may need to see an ophthalmologist or go to the emergency room to receive treatment to restore the vision or limit the deterioration. Many cities have ophthalmological emergency rooms.

Lighting is important in an individual’s environment. Too little light can limit an individual’s vision. Too much light, depending on the individual’s eye condition, such as cataracts or macular degeneration, may cause eye pain and glare. It is important to ascertain whether an individual is sensitive to light. If he or she is sensitive to light, indirect light and night lights may be helpful to provide a safe environment. The majority of older adults benefit from improved lighting. To avoid glare, directing incandescent lamps directly on a task, such as sewing or reading, often improves visual acuity and is well tolerated. Glare occurs when a light shines directly into the eye or reflects off a shiny surface. Low-vision specialists recommend trying different positions and wattage of lighting to find what works best for each individual (Community Services for the Blind and Partially Sighted, 2004).

Encourage the use and proper fitting of the person’s eyeglasses. Older adults’ eyeglasses should be labeled with the person’s name so they can be returned to the owner if they are set down and left behind. Even with eyeglasses, magnification may be helpful. Have family provide lighted magnification if needed (large lighted magnifiers are available from low-vision centers). A low-vision optometrist or specialist can assist in recommending the appropriate level of magnifier.

Contrast sensitivity is a problem with several eye conditions, including cataracts, glaucoma, and macular degeneration. Adding contrast to the edge of each step, fixtures in the home, light switches that blend into the wall, or faucets that blend into the sink can create a safer and more functional environment.

Annual screening is not recommended in the older adult (Chou, Dana, & Bougatsos, 2009). However, nurses should encourage an annual dilated eye exam either with an optometrist or ophthalmologist (Robinson, Mairs, Glenny, & Stokes, 2012). More frequent eye exams may be needed for older adults with diabetes or hypertension, glaucoma, and macular degeneration (American Academy of Ophthalmology Preferred Practice Patterns Committee, 2010). Nurses are members of the interprofessional team responsible for preventing unnecessary disability. Therefore, nurses should make sure that there is a mechanism in place to trigger these visits on an annual basis.

Hearing Impairment

Surveys to identify older adults with hearing impairment often suffer from underreporting on self-report instruments. The latest version of the NHANES included audiometric testing in older adults and found a prevalence rate of 25% in those between 65 and 74 years, and 50% of adults older than 75 years have disabling hearing loss (Dillon et al., 2010; National Institute on Deafness and Other Communication Disorders [NIDCD], 2015a). Hearing loss has been found to be greater in men and progresses more quickly than in women (Chao & Chen, 2009; NIDCD, 2015a). Yet, less than a third of those who could benefit from a hearing aid have ever used them (NIDCD, 2015a). This dramatic increase in prevalence rates is magnified in the nursing home population. Prevalence rates of hearing impairment in the nursing home are similar to rates of visual impairment, at approximately 24% (Warnat & Tabloski, 2006). When hearing is tested through audiometry, the prevalence rates increase to 42% to 90% (Bagai et al., 2006; Cacchione et al., 2003; Tolson, Swan, & Knussen, 2002). The American Academy of Audiology defines hearing loss based on decibels or loudness and the Hertz or the pitch of sound. Normal speech is in the 0- to 25-dB level, mild hearing loss is defined as hearing in the 25- to 40-dB level. Hearing between 40 and 70 dB is considered moderate hearing loss. Severe hearing loss is between 70 and 90 dB; greater than 90 dB is considered profound hearing loss (Mehr, 2007). Aging impairs the processing of sound through the ear canal as well as the central nervous system processing of sounds, making it more difficult to hear the higher frequencies, including women’s and children’s voices (Huang & Tang, 2010).

Assessment of Hearing

Despite the U.S. Preventive Services Task Force not having sufficient evidence to recommend routine hearing screening in older adults, it is essential that older adults are assessed for hearing impairment (Bainbridge & Wallhagen, 2014). Often, it is easy to determine when an older adult is hard of hearing just by having a conversation with him or her. The older adult may lean in closer an attempt to hear better, turn the head to the “good ear,” or cup a hand behind the ear. Older adults may have to ask for things to be repeated; they may report having trouble hearing their grandchildren’s or other’s high-pitched voices. Older adults often complain that people are mumbling. Any or all of these signs may be present. Regardless of whether any of these signs are present, all older adults should have their hearing screened annually at their primary care visit (Bagai et al., 2006). Primary care providers play an important role in screening for hearing loss and making appropriate referrals for older adults (Bainbridge & Wallhagen, 2014). Methods of screening are described herein.

Hearing Handicap Inventory for the Elderly—Screen

The Hearing Handicap Inventory for the Elderly—Screen (HHIE-S; Ventry & Weinstein, 1983) is a 10-item scale used to determine how hearing is impacting an older adult’s daily life and to assist in identifying who might benefit from a hearing aid and an audiology referral. The scale takes approximately 5 minutes to complete and is targeted for community-dwelling older adults. This scale is available online through the Hartford Foundation Institute for Geriatric Nursing “Try This Best Practices in Care for Older Adults” (Demers, 2001). The HHIE-S has reported excellent sensitivity and specificity for severe hearing loss, but the sensitivity and specificity decrease as the level of hearing impairment lessens (Adams-Wendling, Pimple, Adams, & Titler, 2008).

Whisper Test

The whisper test involves covering or rubbing one ear canal, and, from a distance of 2 feet, whispering a three-syllable word on an exhale that the patient either correctly or incorrectly repeats back. An incorrect response triggers a repeat attempt to see whether the older adult can identify a different three-syllable word. The consistency of the level of the whispered word makes this test difficult to compare from examiner to examiner. However, despite this difficulty, it has been found to be a valid and reliable test to screen for hearing loss (Bagai et al., 2006).

Handheld Audioscope

The handheld audioscope is a device developed to specifically screen for hearing impairment. It has a test tone that is presented at the 60-dB level. The decibel levels that may be tested include the 20-, 25-, and 40-dB levels at the 500-, 1,000-, 2,000-, and 4,000-Hz levels (Yueh et al., 2007). The audioscope has an otoscope that allows for the direct inspection of the tympanic membrane or cerumen impactions, which can result in conductive hearing loss present in up to 30% of older adults (Lewis-Cullinan & Janken, 1990; Yueh, Shapiro, MacLean, & Shekelle, 2003). Testing using the audioscope should be performed in a quiet setting and may not be as useful in the long-term care environment with high noise levels. Bagai et al. (2006) recommends a basic algorithm for primary care providers to ask whether the individual has any difficulty with his or her hearing; if yes, then refer for audiometry. If he or she denied difficulty with hearing, then screen with an audioscope, if one is available; if not, the whisper test, which is not as reliable as the audioscope. If the question response, whisper test, or audioscope are positive for a hearing impairment, referral is made for full audiometry.

Pure Tone Audiometry

Pure tone audiometry is the gold standard of hearing tests, particularly if completed in a soundproof booth with 92% sensitivity and 94% specificity in detecting sensorineural hearing loss (Frank & Petersen, 1987). Pure tone audiometry allows for testing of a wide range of decibels and Hertz levels, or loudness and pitch or frequencies, allowing for testing at the 5- to 120-dB level and 250 to 4,000 Hz. Portable pure tone audiometers with noise-reduction earphones are available and can be used in the community, outpatient, and long-term care settings when access to an audiologist is limited. This wide range of tones allows for a better understanding of the individual’s functional hearing. Pure tone audiometry by an audiologist is the next step after screening has identified a hearing deficit (Yueh et al., 2003).

Tuning Fork Tests

Two tuning fork tests have been used in hearing screenings, although one systematic review discouraged their use because they were found to be unreliable with limited accuracy (Bagai et al., 2006). The tuning fork should be either 256 or 512 Hz (M. I. Wallhagen, personal communication, November 18, 2006). The Rinne test is meant to differentiate whether an older adult hears better by bone or air conduction and can help determine whether an individual had sensorineural or conductive hearing loss. The Weber test is used to help identify unilateral hearing loss.

Hearing Changes Common in Older Adults

Conductive hearing loss usually involves abnormalities of the middle or external ear, including the ear canal, tympanic membrane, and ossicular chain of bones in the middle ear (Marcincuk & Roland, 2002; Yueh et al., 2003). Causes of conductive hearing impairment include cerumen impactions or foreign bodies, ruptured eardrum, otitis media, and otosclerosis (Wallhagen et al., 2006; Yueh et al., 2003).

Sensorineural hearing loss is the most common form of hearing loss in older adults (Linton, 2007); it involves damage to the inner ear, the cochlea, or the fibers of the eighth cranial nerve. Sensorineural hearing loss is usually a bilateral progressive onset and is caused by gradual loss of hair cells, and fibrous changes in the small blood vessels that supply the cochlea. Risk factors include heredity, environmental exposure, free radical, and mitochondrial DNA damage (Huang & Tang, 2010). Additional causes of sensorineural hearing loss include viral or bacterial infections, trauma, tumors, noise exposure, cardiovascular conditions, ototoxic drugs, and Ménière’s disease (Wallhagen et al., 2006).

Central auditory processing disorder is an uncommon disorder with prevalence ranging from 0.75% to 14.3% (Gates, Cooper, Kannel, & Miller, 1990; Quaranta et al., 2014) that includes an inability to process incoming signals and is often found in patients with stroke and older adults with neurological conditions such as Alzheimer’s disease and Parkinson’s disease (Pekkonen et al., 1999). The person’s hearing is intact but his or her ability to process the sound is impaired, resulting in impaired speech understanding (Quaranta et al., 2014).

Tinnitus, otherwise known as ringing in the ear, is of two types: subjective and objective. Subjective tinnitus is a condition in which there is perceived sound in the absence of acoustic stimulus (Ahmad & Seidman, 2004; Lockwood, Salvi, & Burkard, 2002). Objective tinnitus is considered rare and presents as ringing in the ear that is audible by the individual and others. It is thought to have a vascular or neurological condition or Eustachian tube dysfunction (Crummer & Hassan, 2004). Subjective ringing in the ears may fluctuate and can be caused by noise-induced damage to the hair receptors of the cochlear nerve and age-related changes in the organs of hearing and balance. Tinnitus can also be caused by hormonal changes, thyroid disorders, and tumors (NIDCD, 2014c). Patients with tinnitus should be referred to an ear, nose, and throat (ENT) specialist.

Ménière’s disease is characterized by fluctuating hearing loss, dizziness, vertigo, tinnitus, and a sensation of pressure in the affected ear (NIDCD, 2010). Ménière’s disease typically begins between ages 40 and 60 years, and sometimes it resolves on its own (NIDCD, 2010). Unfortunately, the fluctuating hearing loss can become permanent hearing loss over time. Possible causes of Ménière’s disease include vascular constriction similar to that found in migraines; viral infections, allergies, and autoimmune disorders and may have a genetic component as Ménière’s disease tends to run in families (NIDCD, 2010).

Implications of Hearing Changes

Older adults who have hearing impairment experience a decreased quality of communication, social isolation, low self-esteem, and generally lower quality of life. More recent, older adults with hearing impairment have been identified as at higher risk of dementia and higher mortality rates (Karpa et al., 2010; Lin et al., 2013). Decreased hearing impacts an individual’s word recognition, decreasing the ability to communicate. This, in turn, can lead to significant safety issues. For example, if patient education about medication administration is provided only verbally, key information can be misheard and misinterpreted. Difficulty understanding the spoken word can lead to fatigue and speech paucity of friends and loved ones.

Speech paucity is described as decreased attempts to have meaningful conversations because of the difficulty in getting the message through to a hearing-impaired loved one. Speech paucity (Wallhagen et al., 2006) leads to social isolation of the hearing impaired because only the necessary information is transferred and no everyday social information is shared (Wallhagen et al., 2004). This can lead to depression and low self-esteem in the hearing-impaired individual and the partner. Other factors that lead to social isolation in hearing-impaired older adults include the inability to hear the phone or the doorbell ringing or knocking at the door.

Ideally, older adults who develop hearing loss will see an audiologist and obtain unilateral or bilateral hearing aids to improve their ability to communicate with the people around them. Unfortunately, the stigma, cost, and delay in pursuing hearing aids are barriers to their success. Hearing aids should be pursued early in the course of hearing impairment. For example, hearing aids can be very helpful when hearing is impaired to the point that background noise interferes with understanding the spoken word. Success in using hearing aids at this level of hearing improves the chance that older adults will continue with hearing aids. Once an individual is offered a hearing aid, hearing rehabilitation should accompany the hearing-aid dispensing; this will increase the use of the hearing aid and positively impact his or her independent living and quality of life (Bainbridge & Wallhagen, 2014; Yueh & Shekelle, 2007). Once older adults become used to the silence, it is hard to adapt to the increased ambient noise heard with hearing aids. Often, older adults require extensive coaching from an audiologist to get through the transition phase of wearing hearing aids. Technology has improved to the point of analog hearing aids that can be finely tuned to the individual’s needs (Bainbridge & Wallhagen, 2014). In one intervention group of older adults fitted with hearing aids, 98% experienced benefit and their caregivers perceived significant benefit as well (Tolson et al., 2002). University settings are often the most cost-effective locations to pursue hearing aids. The cost of hearing aids is an important factor because most insurance plans, including Medicare, do not cover hearing aids, but will cover cochlear implants.

Cochlear implants are another technological advancement that has demonstrated positive outcomes in profoundly deaf or severely hard-of-hearing older adults in the areas of speech recognition (NIDCD, 2014a). A cochlear implant works by bypassing the damaged parts of the ear and stimulating the auditory nerve. These impulses are sent to the brain through the auditory nerve and the brain recognizes them as sound (NIDCD, 2014a). Severe hearing impairment must be present unilaterally or bilaterally before this surgical intervention is considered. In one study, cochlear implants were found to improve word recognition and health-related quality of life (Francis, Chee, Yeagle, Cheng, & Niparko, 2002). At this time, there is only evidence for unilateral cochlear implants in profoundly deaf adults rather than bilateral cochlear implants because of cost and limited functional gain (Bond et al., 2009). Despite these improvements, relatively few adults have received this new technology. As of 2012, according to the U.S. Food and Drug Administration, nearly 58,000 adults have received cochlear implants (NIDCD, 2014a). Technological advances will continue to improve our options for hearing-impaired older adults.

Smell and Taste

Smell and taste are two senses that are difficult to separate because they overlap, particularly, when food is involved. Both these senses are dependent on chemosensation, the ability of the nose, mouth, and throat to identify tastes and smells based on chemical reactions that occur when odors or tastes are present in the environment (American Academy of Otolaryngology–Head and Neck Surgery, 2001). Often when people go to their primary care provider as a result of having lost their sense of taste they are surprised to learn that they have a smell disorder instead (NIDCD, 2014b). The sense of smell and ability to identify odors decrease because of normal changes in aging. Up to 50% of octogenarians have smell disorders (Murphy et al., 2002). This can be problematic for safety reasons. An inability to smell smoke, for instance, could put an older adult at risk. Studies have also linked the loss of smell to Alzheimer’s disease and Parkinson’s disease (Mesholam, Moberg, Mahr, & Doty, 1998; Müller, Reichmann, Livermore, & Hummel, 2002; Oleson & Murphy, 2015; Vasavada et al., 2015). Taste problems are rare, ranging from 0.72% in those aged 65 years and older to 1.7% in those aged 85 years and older (Hoffman et al., 2009).

Changes in Smell and Taste Common to Older Adults

There are four types of olfactory disorders: (a) hyposmia is the reduction of the sense of smell, (b) parosmia is the distortion in the sense of smelling the presence of an odor, (c) anosmia is no sense of smell, and (d) phantosmia is the perception of an odor when no odor source is present (Albers et al., 2006; NIDCD, 2015b). Olfactory disorders impact quality of life, and increase mortality in older adults (Pinto, Wroblewski, Kern, Schumm, & McClintock, 2014). Common complaints from people with olfactory disorders include difficulty with cooking, decreased appetite, eating spoiled food, too little perception of body odor, and inability to detect gas leaks or smoke (Albers et al., 2006; Murphy et al., 2002).

Because of the impact on quality of life and mortality, it is important to take a complete history and physical examination with older adults. A thorough cranial nerve exam and head and neck examination should be included. If an older adult has a subjective complaint of decreased sense of smell or if an olfactory disorder is identified, the individual should be referred to an otorhinolaryngologist by the primary care provider (Miwa et al., 2001; NIDCD, 2015b).

Most changes in taste are thought to occur because of an oral condition, xerostomia (dry mouth), decreased sense of smell, medications, diseases, and tobacco use (Seiberling & Conley, 2004). Dysgeusias or taste disorders may resolve spontaneously. The taste sensory system has the capacity to recover function after being damaged (Hoffman et al., 2009; NIDCD, 2014b). Dysgeusia is defined as a condition in which a foul, salty, rancid, or metallic taste sensation persists in the mouth and can be associated with burning mouth syndrome (NIDCD, 2014b). Additional taste disorders include hypogeusia, which is the decreased ability to taste sweet, sour, bitter, salty, or savory tastes; and ageusia, which is the inability to detect any tastes (NIDCD, 2014b). However, because of the poor outcomes for older adults with taste disorders, referral for treatment is indicated either to an otolaryngologist, neurologist, or a subspecialist at a smell and taste center (Bromley, 2000; Hoffman et al., 2009).

As with olfactory disorders, disorders of taste are often identified on history, not by physical examination. There are very few tests to assess for taste disorders. Therefore, the history is essential. Substance abuse, including tobacco, alcohol, and cocaine, should be reviewed. The individual’s dietary habits should be reviewed. Questions regarding recent dental work or procedures should also be asked. Ascertaining whether the individual has a history of gastric reflux could reveal manageable conditions impacting taste. Other potential causes of taste disorders include upper respiratory and middle ear infections, radiation therapy for head and neck cancers, exposure to chemical and certain medications, head injury, and poor oral hygiene (NIDCD, 2014b). A thorough review of medications is fundamental in the evaluation of a taste disorder (Bromley, 2000).

Diseases That Alter Taste Seen More Frequently as People Age

Burning Mouth Syndrome

Burning mouth syndrome produces a sensation that one’s tongue is tingling or burning. This syndrome is most common in middle-aged and older women (NIDCD, 2014b). There may be several contributing factors: vitamin B deficiencies, local trauma, gastrointestinal disorders causing reflux, allergies, salivary dysfunction, and diabetes.

Xerostomia

Dry mouth is common with many medications used to treat disorders common to older adults, including anticholinergic medications, antidepressants, antihistamines, angiotensin-converting enzyme (ACE) inhibitors, lipid-lowering agents, antiparkinsonian medications, and anticonvulsants, to name a few (Bromley, 2000; Seiberling & Conley, 2004).

Implications of Taste and Smell Changes

Inability to smell limits some of the pleasures of everyday life, decreasing quality of life. The smell of a spring rain, of a Christmas tree, of flowers, or of coffee brewing may not be detectable. Taste is diminished because of the inability to smell. Of significant concern in older adults who have smell and taste disorders is malnutrition. Appetite is detrimentally affected because of the inability to smell and taste the food. Inability to smell is a safety hazard because of the inability to smell smoke in a fire or a gas leak. Decreased sense of taste may also result in inability to recognize spoiled food, resulting in nausea, vomiting, or infectious diarrhea. Because decreased sense of smell is associated with neurodegenerative diseases and increased mortality (Pinto et al., 2014; Vasavada et al., 2015), it is important to investigate potential reversible causes for a person’s decreased sense of smell.

Peripheral Sensation

Two percent to 7% of all patients presenting with symptoms of neuropathy in a general medical practice will have peripheral neuropathy (Smith & Singleton, 2004). In older adults in an NHANES study, older than 70 to 79 years, 28% reported the loss of feeling in their feet; this increased to 35% in adults older than 80 years (Dillon et al., 2010). This is important because poor nerve function can impact late-life disability (Ward et al., 2014). A prospective study evaluating older adults for peripheral sensory neuropathy found prevalence rates of 26% for those 65 to 74 years old and 54% for those 85 years and older (Mold, Vesely, Keyl, Schenk, & Roberts, 2004). Common disorders that increase the risk of peripheral neuropathy include diabetes; alcoholism; osteoporosis with compression fractures; peripheral vascular disease; infections; nutritional deficiencies, particularly of vitamins (e.g., thiamine and B₁₂); and malignancies (Mold et al., 2004). Because of the multitude of risk factors for peripheral neuropathy, a neurology consultation is recommended for complicated presentations of peripheral neuropathy to help determine the appropriate evaluation and management of the condition.

Changes in Peripheral Sensation Common to Older Adults

Conditions that alter peripheral sensation are seen more frequently as people age and include peripheral neuropathy, diabetic neuropathy, phantom limb pain, and acute sensory loss.

Peripheral Neuropathy. This is a heterogenous group of disorders (Merkies, Faber, & Lauria, 2015) that present with nerve pain in the distal extremities related to nerve-fiber damage in the motor, large sensory, small sensory, and autonomic nerve fibers from underlying systemic illnesses, neurotoxic drugs, primary disorders of the immune system, and hereditary disorders (Merkies et al., 2015). The most commonly suspected causes are circulatory problems (peripheral vascular disease and diabetes) or vitamin deficiencies. Common vitamin deficiencies that impact peripheral nerves include thiamine and B₁₂.

Diabetic Neuropathy. This is end-organ damage to the peripheral nerves from microvascular changes that occur with diabetes. It often leads to loss of sensation in the feet of diabetics, contributing to undetected trauma to the extremities and subsequent refractory infections because of poor vascular supply to the extremity. It is extremely important to teach diabetics and patients with peripheral neuropathy to provide special attention and care to their feet.

Phantom Limb Pain. This is the experience of pain that can range from dull ache to crushing pain where an amputated limb once was. The sensory cortex of the brain has influence in this mechanism. This pain is often chronic and requires special interventions for control and management, including electronic prosthetics, analgesics, and psychosocial support.

Acute Sensory Loss. Acute sensory loss may be caused by a stroke, acute nerve entrapment in the spine, traumatic nerve damage, or compartment syndrome resulting from trauma to a limb. This sensory loss presents with acute onset of numbness, tingling, severe nerve pain, or lack of sensation and function in the affected extremity.

Implications of Peripheral Sensation Changes

Inability to recognize position sense, pressure, or to ascertain where feet are positioned on the floor can lead to falls, burns, lacerations, calluses, and pressure ulcers. Intact peripheral sensation is essential for remaining safe in the environment.

Nursing Assessment and Care Strategies of Peripheral Sensation

Nurses should take appropriate health histories to ascertain the presence of decreased sensation or pain in limbs. Physical examination should always include a thorough inspection and physical examination of the individual’s legs and feet (Hellman, 2002) or the affected extremity. Diabetics and people known to have peripheral neuropathy should have thorough neurological exams, including vibratory sense with a tuning fork over bony prominences and Semmes–Weinstein monofilament testing of the feet along with testing proprioception (Boike & Hall, 2002). A referral to neurology may be necessary for nerve conduction testing, which is the most important tool in the diagnostic workup of older adults with suspected peripheral neuropathy (Merkies et al., 2015).

Semmes–Weinstein Monofilament Test

This inexpensive simple procedure is used to screen for decreased sensation in several plantar sites on the foot. The Semmes–Weinstein monofilament is placed against the sole of the foot in eight different areas on the foot. The individual is asked to report when he or she perceives any sensations (Boike & Hall, 2002). The Semmes–Weinstein nylon monofilament 5.04 gauge buckles at a pressure of 10 g. Loss of sensation at this level of pressure indicates a risk for ulcer development. Identification of this risk is important for improving the vigilance of foot care (Armstrong & Lavery, 1998).

Vibratory Sense

This is assessed by using a 128-Hz vibrating tuning fork on a lower extremity bony prominence. The examiner places the vibrating tuning fork on the bony prominence and asks the individual whether he or she feels any vibration (Boike & Hall, 2002). Older adults should be able to feel the vibration.

Proprioception

This is the ability of individuals to determine where they are in space. To assess for deficits in proprioception in the feet that may set the older adult up for falls and local trauma, the examiner has the individual close his or her eyes, then the examiner holds the large toe on the sides and moves the toe up or down and asks the individual to identify which direction the toe was moved. Inability to correctly identify the direction is an indication of decreased proprioception.

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