Risk factors for type II diabetes and diabetic retinopathy in a Mexican-American population: Proyecto VER

PURPOSE: Risk factors for type II diabetes and diabetic retinopathy were determined in a population-based study of Mexican-Americans. DESIGN: Proyecto VER (Vision, Evaluation, and Research) is a cross-sectional study in a random sample of the self-described Hispanic populations in Tucson and Nogales, Arizona, age 40 and older. METHODS: Of 6,659 eligible subjects, 4,774 (72%) participated in the home questionnaire and clinic visit. Diabetes was defined as self-report of a physician diagnosis or hemoglobin A_1c value of ≥ 7.0%. Only type II diabetes was included. Diabetic retinopathy was assessed on stereo fundus photographs of all persons with diabetes. Questions were asked about demographic, personal, socioeconomic, and diabetes related variables. RESULTS: 1023 (21.4%) of the sample had type II diabetes, and 68% were in the low-income group (annual income less than $20,000). Diabetes was associated with Native-American ancestry, higher acculturation, low income, less education, and increasing body mass index after age and gender adjustment. Persons with previously undiscovered diabetes were more likely to have no regular source of care, no insurance, and currently smoke compared with persons with known diabetes. Only low income was related to proliferative retinopathy, once adjusted for other factors (odds ratio [OR] = 3.93, 95%, confidence limitations [CL] = 1.31-11.80). CONCLUSIONS: Several socioeconomic and other factors were associated with diabetes, but few were related to diabetic retinopathy. Persons in the low-income group appeared to be at greater risk of diabetes and the ocular complications of diabetes compared with those with more income. Further longitudinal studies in this population are needed to confirm the associations.