Vision and Falls in the Elderly
Over 50% of patients in a long term care facility have a fear of falling. (1) Many find themselves in long term care facilities as the result of falls, Accidental falls are the second leading cause of death after traffic accidents.(2) As therapists, we see first hand the effects of falls and are on the front lines helping to prevent falls.
With poor balance being one of the more frequently cited problems related to falls in the elderly, the link between vision and balance should also be considered.
Visual causes of falls
Visual acuity problems, reduced contrast sensitivity, and reduced depth perception are all sited as correlating with the incidence of falls. These visual skills are easily assessed and should a part of the fall survivor’s assessment.
Acuity can be assessed using a Snellen Chart, where patients read letters as they would do in the eye doctor’s office. One should assess each eye separately then both together. *
Even small visual acuity reductions, as little as 20/30, was shown to increase fall risk with the risk increasing as the acuity becomes poorer.
Contrast sensitivity is a visual skill * that allows a person to discern an object from its background. Reduced contrast sensitivity can occur as a result of several common visual diseases including:
- Macular degeneration
- Diabetic retinopathy
It is easily tested using the Pelli Robson contrast sensitivity chart.
Depth perception is the third most common visual problem associated with falls in the elderly*. Depth perception requires good acuity and binocular vision skills for a person to perceive three-dimensional space accurately. Depth perception is most easily assessed using the RanDot Stereo test, but this can be expensive.
Assessing these skills should be a part of the fall survivor’s assessment, as one would assess range of motion and strength.
Vision and Balance
The magnocellular tract of the brain gives input to the cerebellum and parietal lobes. This visual information, collected from the peripheral, sends signals to these areas to allow for the adjustment of posture and gait based on visual information. The reduced acuity and contrast sensitivity is often seen in the elderly population can affect the accuracy of this information as can conditions like glaucoma which affects peripheral vision.
Some studies have suggested even the use of multifocal lens (bifocals and “no line” bifocals), because of the distortion of the walking surface during ambulation, could be contributing to falls. (3)
What can we do?
Ask about your patient’s visions and assess their visual skills. Ask about the type of glasses they are wearing and recommend single vision glasses for those patients with a history of fall s that are using a multifocal lens. Vision Mechanic.Net has some great videos and articles produced by Dr. Charles Boulet and Robert Constantine, Occupational therapist.
* These brief assessments, while helpful, are no replacement for a complete eye exam. Every patient needs regular eye exams.
(1)Lach, H. W., & Parsons, J. L. (2013, August). Impact of fear of falling in long term care: An integrative review. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/23602257
(2)Saftari, L. N., & Kwon, O. (2018, April 23). Aging vision and falls: A review. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5913798/
(3)Lord, S. R., Dayhew, J., & Howland, A. (2002, November). Multifocal glasses impair edge-contrast sensitivity and depth perception and increase the risk of falls in older people. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/12410892