MODERATE-TO-SEVERE DIABETIC-RETINOPATHY IS MORE PREVALENT IN MEXICO-CITY THAN IN SAN-ANTONIO, TEXAS

OBJECTIVE - To compare the prevalence of diabetic retinopathy (DR) bet ween low-income Mexicans from Mexico City and Mexican-Americans from S an Antonio, Texas. RESEARCH DESIGN AND METHODS - We designed a cross-s ectional population-based study in low-income neighborhoods of Mexico City and San Antonio. The men and nonpregnant women included in the st udy had NIDDM and were between 35 and 64 years of age. Ophthalmologic evaluation was performed in 414 patients, 204 in San Antonio and 210 i n Mexico City. Seven field standard stereophotographs of each eye were obtained, adapting the Early Treatment Diabetic Retinopathy Study pro tocol, and graded at the Fundus Photograph Reading Center of the Unive rsity of Wisconsin. RESULTS - Early nonproliferative DR occurred in 37 (17.6%) and 39 (19.1%) patients in Mexico City and San Antonio, respe ctively. Moderate-to-severe nonproliferative DR occurred in 55 (26.2%) and 37 (18.1%) patients in Mexico City and San Antonio, respectively, and proliferative DR occurred in 12 (5.7%) and 7 (3.4%) patients in M exico City and San Antonio, respectively. Using univariate and multiva riate logistic regression analysis with DR as the dependent variable, age, duration of disease, and fasting glucose concentration were posit ively and significantly associated with retinopathy, whereas city, sys tolic blood pressure, and other selected metabolic variables were not. We defined moderate-to-severe DR to include the categories of moderat e-to-severe nonproliferative and proliferative DR. For this combined c ategory, Mexico City patients with diabetes had a significantly higher prevalence (P < 0.01) than those from San Antonio when analyzed by mu ltiple logistic regression analysis (odds ratio for Mexico City/San An tonio, 1.72; 95% CI 1.10-2.70). CONCLUSIONS - Overall prevalence of DR is similar in both cities. However, moderate-to-severe DR is signific antly higher in Mexico City.