Non-standard Vision Measures Predict Mortality in Elders: The Smith-Kettlewell Institute (SKI) Study

Purpose—To determine which vision tests predict mortality within 10 years in a communitybased elderly sample. Methods—Nine hundred residents of Marin County, CA, aged 58 to 101 (mean 75 years at baseline), underwent a battery of tests, including high contrast acuity, low contrast acuity, low contrast/low luminance acuity, acuity in glare, contrast sensitivity, color vision, stereopsis, standard and attentional fields. The association between the vision tests and mortality within 10 years of baseline was assessed with Cox Proportional Hazards models controlling for age, sex, education level, depression, cognitive status and self-reported medical conditions. Results—Forty-three percent of the sample died within 10 years of baseline. When controlling for mortality-related covariates, impairment in any of the vision measures was associated with increased risk of death. However, non-standard vision measures (i.e. impairment in low contrast/low luminance acuity, standard field integrity and the impact of the attentional task on field integrity) were more highly associated with mortality than standard high contrast acuity. Conclusions—In agreement with other studies, we find that visual impairment is a significant predictor of death. However, the strongest relationship was found for measures other than high contrast acuity. These results suggest that non-standard vision measures may be more sensitive indicators of generalized aging in the oldest-old.