Visual impairment and risk of hip fracture

As part of a case-control study, the Auckland Hip Fracture Study (1991-1994), the authors examined associations between impaired vision and risk of hip fracture. Subjects (911 cases and 910 controls aged 60 years or older) completed a questionnaire and had vision measurements taken, including measurements of visual acuity and stereopsis (depth perception). Binocular visual acuity worse than 20/60 was statistically significantly associated with increased risk of hip fracture after adjustment for age, sex, proxy response, hours of activity per week, and height (odds ratio (OR) = 1.5; 95% confidence interval (CI): 1.1, 2.0), as was having poor vision (less than 20/100) in both eyes (OR = 2.4; 95% CI: 1.0, 6.1). Having no depth perception was ;associated with increased risk (OR = 6.0 95% CI: 3.2, 11.1), as were categories of decreasing stereopsis (trend p = 0.0001), self-reported poor vision (OR = 1.4; 95% CI: 1.0, 1.9), not wearing glasses at the time of the fall (OR = 1.2; 95% CI: 1.0, 1.6), and increasing time since the last eye examination (trend p = 0.03). The population attributable risk of hip fracture due to poor visual acuity or stereopsis was 40%. Visual factors are important fall-related factors which influence risk of hip fracture. Risk of hip fracture may be decreased by correcting refractive error, improving stereopsis, and administering regular eye examinations.