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4
eDUcATIOnAL OBjecTIVes
On completion of this chapter, the reader should be able to:
1. describe the normal changes of aging that affect the senses in the older adult 2. identify common disorders that impact the senses in the older adult
3. determine how best to assess sensory status in the older adult
4. identify nursing strategies to manage sensory impairment in the older adult
5. collaborate with interprofessional team members who can assist the older adults with sensory impairment
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. As people age, they often experience changes in their sensory func- tion (vision, hearing, smell, taste, and peripheral sensation). These sensory changes can negatively impact the older adults’ ability to interact with their environment, decreasing their quality of life. For example, changes in hearing can impact an older person’s com- munication skills; changes in vision can impact their health literacy limiting their ability to take medications safely. 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.
Understanding how to assess the senses as well as manage sensory deficits is essen- tial to holistic nursing. A goal of Healthy People 2020 is to decrease the prevalence and
Pamela Z. Cacchione
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 will also be addressed.
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 4.1).
Vision
There are several changes that occur with vision as people age. The eyelids start to lag, 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], 2004a; Whiteside, Wallhagen, & Pettengill, 2006).
Hearing
Normal changes of aging impacting hearing 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.
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 radical, and mitochondrial deoxy- ribonucleic acid (DNA) damage (Huang & Tang, 2010). Presenting clinical symptoms of this irreversible condition includes 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 sex with older males being more prone to smell loss (Hoffman, Cruickshanks, & Davis, 2009). The environment, trauma, diseases, or illness can diminish
TABLE 4.1
Normal Changes of Aging
Sense Change of Aging Functional Outcome
Vision n Decreased dark adaptation
n Decreased upward gaze
n Eyes become drier and produce less tears
n Cornea becomes less sensitive
n Pupils decrease in size
n Visual fields become smaller
n Increased safety risk in changing environmental light
n Decreased field of vision
n Dry irritated eyes
n Slow to recognize injury to the cornea
n Inability to adjust to glare and change in lighting conditions
n Safety risk for driving and maneuvering in the environment
Hearing n Ear drum thickens
n Loss of high-frequency hearing acuity
n Decreased ability to process sounds after age 50
n Increased cerumen impactions
n Thickened ear drum decreases sound moving across the ear canal
n Decreased ability to hear sounds, such as /p/, /w/, /f/, /sh/, and women’s and children’s voices
n Requires more time to process and respond to auditory stimuli
n Decreased hearing because of blockage of sound Smell n Decreased ability to identify odors
n Impacts ability to taste
n Inability to identify spoiled food or smoke
n Limits enjoyment in eating Taste n Decreased number of taste buds
n Limited decrease in taste supported by studies
n Less saliva production
n Decreased sensitivity to flavors
n Dry mouth affecting ability to swallow
Sensation n Decreased vibratory sense
n Decreased two-point discrimination
n Decreased temperature sensitivity
n Decreased balance
n Decreased proprioception
n Changed pain sensation
n Increases risk for injury
n Decreased ability to sense pressure
n Decreased protective response to withdraw from hot objects
n Risk of falls
n Risk of falls
n Decreased protective mechanism
Note. Adapted from: Bromley, S. M. (2000). Smell and taste disorders: A primary care approach. American Family Physician, 61(2), 427–436, 438. Evidence Level VI. Linton, A. D. (2007). Age-related changes in the special senses.
In A. D. Linton & H. W. Lach (Eds.), Matteson & McConnell’s gerontological nursing, concepts and practice (3rd ed., pp. 600–630). St. Louis, MO: Saunders Elsevier. Evidence Level V. Murphy, C., Schubert, C. R., Cruickshanks, K. J., Klein, B. E., Klein, R., & Nondahl, D. M. (2002). Prevalence of olfactory impairment in older adults. Journal of the American Medical Association, 288(18), 2307–2312. Evidence Level III. Schiffman, S. S. (1997). Taste and smell losses in normal aging and disease. Journal of the American Medical Association, 278(16), 1357–1362. Evidence Level V. Seiberling, K. A., & Conley, D. B. (2004). Aging and olfactory and taste function. Otolaryngologic Clinics of North America, 37(6), 1209–1228. Evidence Level V. Wallhagen, M. I., Pettengill, E., & Whiteside, M. (2006). Sen- sory impairment in older adults: Part 1: Hearing loss. The American Journal of Nursing, 106(10), 40–48. Evidence Level VI. Whiteside, M. M., Wallhagen, M. I., & Pettengill E. (2006). Sensory impairment in older adults: Part 2: Vision loss. The American Journal of Nursing, 106(11), 52–61. Evidence Level V.
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 Alzheimer’s disease (Albers, Tabert, & Devanand, 2006; 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
to 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. Data from the National Health and Nutrition Examination Survey (NHANES; Dillon, Gu, Hoffman, & Ko, 2010) in older adults aged 70 years and older identified, 15.4% were found to be visually impaired but this varied by race and ethnicity with non-Hispanic Whites (13.8%), non-Hispanic Blacks (21.1%), and Mexican Americans (24%). In adults aged 80 years and older, 24.6% were found to be visually impaired (Dillon et al., 2010). In another study, adults aged 80 years and older are 7.7% of one study but accounted 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 from 27% to 54% of older adults with visual impairment (Bron & Caird, 1997;
Cacchione, Culp, Dyck, & Laing, 2003). 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% of those were impaired because of an uncor- rected refractive error (Vitale, Cotch, & Sperduto, 2006). Leading causes of blindness by race and ethnicity was found to be macular degeneration in Whites, cataracts and open-angle glaucoma in Blacks, and open-angle glaucoma in Hispanic persons (Con- gdon 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, 2004a).
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:
n Normal vision: visual acuity of 20/20 or better
n Mild vision impairment: 20/25 to 20/50
n Moderate visual impairment: 20/60 to 20/160
n Severe visual impairment (legally blind): 20/200 to 20/400
n Profound vision impairment: 20/400 to 20/1,000
n Near-total vision loss: less than or equal to 20/1,250
n Total blindness: no light perception
Low vision can also be defined based on visual field limitations. Severe visual impair- ment is defined as best corrected field less than or equal to 20 degrees (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 pre- dispose older adults to visual impairment. Diabetes is a common cause of disease-related blindness related to diabetic retinopathy, with 6% of diabetics older than the age of 65 years developing diabetic retinopathy (Baker, 2003; NEI, 2004b). Hypertension car- ries 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 4.2 ( Cacchione, 2007; Wallhagen, Pettengill, & Whiteside, 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.
Cataracts in severe cases 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 cor- neal problem, not a cataract. If the person has had cataract surgery, the lens implant may be visible on close inspection.
Fundus Exam. Using an ophthalmoscope, a nurse can visualize the red reflex and, with expe- rience and practice, the fundus of the eye. This is often difficult with small pupils. Dark- ening the room may help with dilating the pupils. Optometrists and ophthalmologists
TABLE 4.2
Vision History Questions
n When was your last eye exam?
n How would you describe your eyesight?
n Any change in your eyesight?
n When did you notice this change?
n Are you experiencing any blurred vision?
n Are you having any double vision?
n Are you bothered by glare?
n Are you experiencing any eye pain?
n Are you using any eye drops for any reason?
n Any history of trauma or injury to your eyes?
n Have you had any eye surgeries?
n Do you have cataracts?
n Any family history of eye problems?
Note. Adapted from: Cacchione, P. Z. (2007). Nursing care of older adults with age-related vision loss. In S. Crocker- Houde (Ed.), Vision loss in older adults: Nursing assessment and care management (pp. 131–148). New York, NY:
Springer Publishing. Evidence Level VI. Whiteside, M. M., Wallhagen, M. I., & Pettengill E. (2006). Sensory impairment in older adults: Part 2. Vision loss. The American Journal of Nursing, 106(11), 52–61. Evidence Level V.
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 com- pleted with 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 ft. The individual is asked to read the letters on the chart until he or she miss 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 m. 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 to 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 do not have glasses, 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 non-copyrighted 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 cm 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 con- ditions of the eye. Decreases in contrast sensitivity occur with cataracts, glaucoma, and retinopathies (Mäntyjärvi & Laitinen, 2001; Wilensky & Hawkins, 2001). Contrast sensitivity provides information on how well an individual may perform in real-life con- ditions. 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.
The Pelli–Robson Contrast Sensitivity Chart (Pelli, Robson, & Wilkins, 1988) is read at the 1- or 3-m 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 recog- nizing 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 the lines within the circle are pointed (Morse & Rosen- thal, 1997).
Visual Fields. Fields of vision refers to the area of peripheral vision visible when the indi- vidual is focusing straight ahead (Cassin & Rubin, 2001). The vision in visual fields can be affected by many eye conditions, as well as neurological disorders that inhibit eye movement or affect the blood supply to the optic nerve. Intact visual fields are impor- tant 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 if 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 measure 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 con- dition. For example, unilateral visual field deficits may be related to a cerebral vascular accident, glaucoma will affect the peripheral fields, and macular degeneration has asso- ciated central field of vision loss.
Stereopsis. Stereopsis is the process where 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 dis- eases (Norman et al., 2008).
Visual function Questionnaire-25
The NEI Visual Function Questionnaire (VFQ) is a 25-item survey that assesses the functional impact 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, Depen- dency, 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).