A respondent was considered to have diabetes if he or she had a self-reported previous diagnosis of the disease (excluding gestational diabetes mellitus). Age was categorized as 20 to 64 years and 65 years and older. Race/ethnicity was categorized as non-Hispanic white, non-Hispanic black, Mexican American, and other (including those who selected multiple races and non–Mexican American Hispanic). Other factors included in the analysis were sex, marital status, educational level (<high school, high school, and >high school), income (poverty income ratio<1 [ie, below the poverty threshold], 1 to <2, and ≥2), health insurance, high blood pressure, smoking, and body mass index (BMI) (calculated as weight in kilograms divided by height in meters squared). High blood pressure affects the development of age-related macular degeneration,23 diabetic retinopathy,24,25 and other retinal vascular diseases.26 We defined high blood pressure as an average (based on 4 readings) systolic blood pressure of 140 mm Hg or higher or an average diastolic blood pressure of 90 mm Hg or higher. Smoking is associated with age-related macular degeneration,23,27- 29 cataract,30- 32 and diabetic retinopathy.15,33 We defined smoking status as current smoker, previous smoker, and those who never smoked. We controlled for BMI because some of the studies suggested a possible association between BMI and several ocular conditions, such as age-related maculopathy34- 37 and cataract.38,39 We divided respondents into 3 groups based on their BMI: normal/underweight (<25), overweight (25 to <30), and obese (≥30).