Importance: Further research is crucial to better understand the reason for falls in individuals with visual impairment (VI) and to develop appropriate fall prevention strategies.
Objective: To compare balance measures in individuals with normal vision, VI, and uncorrected refractive error (URE).
Design and setting: Cross-sectional study based on a national survey sample.
Participants: A total of 4590 adults, 40 years or older, participating in the 2001 through 2004 National Health and Nutrition Examination Survey.
Main outcome measures: Participants completed tests of standing balance with eyes open or eyes closed on a firm or compliant (foam) surface. Eyes-closed testing on a foam surface primarily assessed vestibular balance by minimizing visual and proprioceptive inputs. The main outcome measure was time to balance failure on firm and foam surface testing. Participants also self-reported difficulty with falling during the last year.
Results: Failure during eyes-open balance testing conditions or eyes-closed balance testing on a firm surface was not more common among participants with VI-associated or URE-associated vision loss (P > .22). In eyes-closed foam surface balance testing, multivariable models demonstrated higher rates of balance loss with VI-associated vision loss (P = .02) and with URE-associated vision loss (P = .04) (hazard ratio, 1.7 per logarithm of the minimum angle of resolution [logMAR] unit change [10 lines] for both). Self-reported falling difficulty was associated with worse VI (odds ratio, 3.7 per logMAR unit change; P = .03) but not with worse URE (odds ratio, 3.4 per logMAR unit change; P = .14).
Conclusions and relevance: The vestibular contribution to balance (measured with eyes closed on a foam surface) was worse for individuals with VI or URE. Reduced visual inputs may weaken the vestibulo-ocular reflex, an important system that maintains the effectiveness of vestibular balance. Alternately, common degenerative pathways or lower physical activity levels may affect balance, particularly among those with VI.