Visual impairment and frailty: Examining an understudied relationship

Background: Older adults with visual impairments are at increased risk of negative health outcomes. Here, we investigate the association between visual impairment and frailty. Methods: Cross-sectional and longitudinal relationships between visual impairment (distance visual acuity) and frailty (frailty phenotype criteria) were examined using data from the National Health and Nutrition Examination Survey (NHANES, 1999-2002, ≥60 years) and the Women's Health and Aging Studies (WHAS III). Imbalance of potential confounders, particularly age, was addressed using propensity score-based adjustment. Multinomial logistic regression determined the odds of prefrailty and frailty at baseline in NHANES and ordinal logistic regression examined the odds of baseline and incident frailty over 3 years in WHAS III after adjustment for confounders and probability weighting (survey weights × inverse propensity scores). Results: In NHANES (n = 2,639, 9% vision impairment), participants with visual impairment were more likely to be prefrail (odds ratio [OR] = 3.2; 95% confidence interval [CI]: 1.9-5.3) and frail (OR = 3.7; 95% CI: 1.5-9.2) than those without visual impairment. In WHAS III (n = 796, 26% mild, 37% moderate/severe vision impairment), participants with mild and moderate/severe vision impairment were more likely to be frail (OR = 2.0; 95% CI: 1.5-2.5; OR = 5.5; 95% CI: 4.2-7.2, respectively). A one-line worse visual acuity (0.1 logMAR increase) was associated with greater odds of frailty (OR = 1.5; 95% CI: 1.4-1.7). Of those non-frail at baseline (n = 549), moderate/severe visual impairment and one-line worse visual acuity was associated with greater odds of incident frailty (OR = 3.5; 95% CI: 1.4-8.4; OR = 1.3; 95% CI: 1.1-1.5, respectively) over 3 years. Conclusions: Visual impairment may be an important, yet understudied risk factor for frailty.