The most common cause of gait instability in the elderly is the “multiple sensory deficit” syndrome. That means that disturbances of proprioception, vision, vestibular function, and maybe even hearing, each of which may not be enough to affect gait become severe enough collectively to affect gait. So, as a neurologist, we are often recommending to our patients with gait disturbances that they get their vision corrected.
But in our June 2010 What’s New in the Patient Safety World column “Seeing Clearly a Common Sense Intervention” we noted that sometimes new glasses may paradoxically result in increased falls.
Recently we came across an outstanding paper in the optometry literature (Elliott 2014) that nicely summarizes the physiological links between vision and gait, the epidemiology of falls and vision disturbances, and the evidence base linking falls to changes in patients’ corrective lenses.
The author notes that 57% of falls in older adults are due to trips, slips, and stumbles and that steps, stairs and curbs are the most common environmental hazards contributing to falls. He also notes that falls with injury are 3 times more likely when descending stairs compared to ascending them. He goes on to describe how corrections to vision that involve magnification and/or changes in astigmatism may affect their function during such activities as descending stairs.
Elliott describes the literature linking visual impairment to falls and notes this is likely an underestimate. But he then goes on to describe the literature on the impact of optometric interventions and/or cataract surgery on the fall rate. One of the most striking studies cited was a randomized controlled trial (RCT) in which community-dwelling patients aged 70 and older were given an optometric intervention (most often new glasses) compared to those receiving just usual care (Cumming 2007). Surprisingly, the fall rate was higher in the intervention group in the first year (65% vs. 50%).
Elliott also notes the literature on the relationship between bifocals and progressive lenses and falls (see also our June 2010 What’s New in the Patient Safety World column “Seeing Clearly a Common Sense Intervention” regarding bifocals).
Elliott concludes with several practical recommendations for optometrists:
We don’t expect that you’ll read through all the optometric details in the paper. But you should be cognizant of the practical recommendations in the paper to be conservative with any changes made to correct your patients’ vision. We’d actually go as far as recommending that, for your patients who have multiple fall risk factors, you provide them a copy of this paper to take with them to their ophthalmologist or optometrist visit!
Elliott DB. The Glenn A. Fry Award Lecture 2013: Blurred Vision, Spectacle Correction, and Falls in Older Adults. Optometry & Vision Science 2014; 91(6): 593-601
Cumming RG, Ivers R, Clemson L, Cullen J, Hayes MF, Tanzer M, Mitchell P . Improving vision to prevent falls in frail older people: a randomized trial. J Am Geriatr Soc. 2007; 55: 175–81
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