Prevalence of diabetic retinopathy in adult Latinos

Objective To estimate age- and gender-specific prevalence of diabetic retinopathy (DR) and to determine the association of type, duration, and treatment of diabetes with the prevalence of DR in adult Latinos. Design Population-based cross-sectional study. Participants Six thousand three hundred fifty-seven Latinos aged 40 years and older from 6 census tracts in Los Angeles, California. Methods The study cohort consisted of all self-identified Latinos of primarily Mexican ancestry aged 40 years and older residing in 6 census tracts in La Puente, Los Angeles County, California. All participants diagnosed with diabetes underwent a complete ophthalmologic examination, including stereoscopic fundus photography (7 standard Early Treatment Diabetic Retinopathy Study fields). Photographs were graded in a masked manner using a modified Airlie House Grading System to assess presence and severity of DR. Main outcome measures Prevalence of nonproliferative DR, proliferative DR, and macular edema. Results Of 1263 participants with definite diabetes mellitus, gradable fundus photographs were available in 1217 participants (96%). Of those 1217 participants, 46.9% had DR. Severe nonproliferative DR and proliferative DR were present in 4.4% and 6.1% of diabetics, respectively. Macular edema was observed in 10.4% and clinically significant macular edema was observed in 6.2% of all diabetics. No age- or gender-related differences were present. After adjusting for duration of diabetes, the prevalence of DR was similar in persons with type 1 and type 2 diabetes. Conclusions Our data suggest that the prevalence of DR is high among Latinos of primarily Mexican ancestry. The increase in prevalence of DR with longer duration of diabetes emphasizes the public health importance of early diagnosis and management in Latinos. Further data on incidence and progression are required to understand better the natural history of DR in Latinos.