BetterConduct

According to the American Nurses Credentialing Center (ANCC), normal changes in vision with aging include:

Decreased dark adaptation to changes in light

Decreased field of vision

Drier eyes and fewer tears

Decreased pupil size

Less sensitivity in cornea

Increase in presbyopia (loss of elasticity in the lens)

 (ANCC Course:  Geriatric Special Topics: Sensory Changes, September 21, 2017)

 

In elders without dementia, pupils take longer to adjust to changes in light.  There is a decrease in the ability to focus on near objects such as the words on a page (National Eye Institute, 2010 in AANC September 21, 2107; Whiteside et al, 2006). According to a 2004 study, more adults aged 80 and over accounted for almost 70% of the cases of blindness (Congdon et al., 2004). Diabetes can also be a source of disease-related blindness, as can glaucoma.  Glaucoma is an increase in eye pressure that results in atrophy of the optic nerve head, and no cure is available.  Glaucoma is the world’s leading cause of blindness (National Eye Institute, 2014). 

 

One very impactful aspect of vision change in the aged is contrast sensitivity.  Contrast sensitivity is the ability to discern changes in surface area elevations, such as stairsteps or door frames. Objects may look closer than they appear, or an image of an object could be confused with the actual object (a picture might be mistaken for the real thing).   It can also affect the ability to distinguish items that are of similar color.  An adaptation to increased contrast would be to include colored painter’s tape where surfaces change elevation or use a shaded sandpaper skid tape on stairs.  Light switches and buttons on phones or remotes may need colored dots to be seen more easily.  Nail polish or stickers can work well for this. 

 

Field of vision, especially peripheral vision, can be limited in the elderly.  It is always best to approach the dementia client on the dominant side (which side of the body they prefer to use; it will usually be the strongest side of their body), and to address the client while in front of them so you are in their field of vision.  My father frequently does not get close enough to a chair to sit down or moves past the chair before it could be moved behind him.  This would occur both at his easy chair and at the dining room table.  Prompting him to step farther past the area where he thought he should be resulted in agitation and associated grumbling.  We decided to cut out footprints from adhesive felt and place these on the floor to indicate where his feet needed to be before he sat down.  This worked best when we allowed enough time for him to respond to our request to ‘step on the feet’. 

 

If the individual is sensitive to light, particular attention should be paid to issues of glare and reflectivity.  Night lights and indirect lighting may be used.  More time should be given for the client to adjust to changes in light when going outside or coming into the house.  Even getting into the automobile may require more time for adjustment as the car provides a shadow inside and many interiors have dark toned upholstery and dashboards.  Natural sunlight is best for visual acuity (Johnson, 2017). 

 

Of particular interest is the presence of mirrors and dementia.  Some experts hypothesize that mirrors can be feared by clients with dementia because they might not recognize their own reflection and mistakenly interpret that a “stranger” is in the room (Peterson, 2019).  Mirrors can be covered or removed, and shades or curtains can be drawn in the early evening to avoid a reflection of the interior of the room. In my father’s instance, he has always been wary and afraid of falling in the bathroom, which is where most mirrors are located.  He also does not like to see a reflection of himself being dressed or changed as this accentuates his feelings of helplessness and dependence on others. 

 

Dementia clients may have difficulty discerning color.  Per Johnson (2017), dementia clients have difficulty discriminating between yellow and blue, among light colors, and between close colors on the color wheel such as blue and green or blue and violet.  Colors with the same intensity, like dark green and bright red or yellow against white provide poor contrast and may not be seen as different.  Close colors can become an issue when dinner plates and tablecloth/ tabletop are close in hue or bathrooms are predominantly white.  Use contrasting plates and tablecloth and a bright shower curtain with light bathroom tile. Vinyl bath stickers can be placed on tile or in the shower.  Johnson also stated that kelly or emerald green is the last color Alzheimer’s patients can perceive (Johnson, 2017). 

 

Sources:

American Association of Colleges of Nursing. (2017, September 21).  Geriatric special topics:  Sensory changes.  Retrieved from https://www.elitecme.com. 

 

Congdon N, O’Colmain B, Klaver C, Klein R, Munoz B, Friedman D, Kempen J, Taylor H, Mitchell P.  Causes and prevalence of visual impairment among adults in the United States.  Archives of Ophthalmology 2004;122(4),477-485.

 

Johnson PR (2017, March).  Dementia: Cognitive Rehabilitation Strategies for Effective Evaluation & Treatment, PESI Seminar, Dallas, Texas.

 

Peterson S. (2019, January).  Understanding Dementia. Lecture presented at Willowbend Assisted Living and Memory Care, Denton, TX.

 

Whiteside M, Wallhagen M, Pettengill E.  Sensory impairment in older adults:  part 2: vision loss.  Am J of Nursing, 2006;106(11):52-61.