Abstract
Purpose: :
To examine four-year incidence of diabetic retinopathy (DR) and clinically significant macular edema (CSME).
Methods: :
The Los Angeles Latino Eye Study (LALES) is a population-based cohort study of primarily Mexican-Americans. Participants were considered at risk for DR or CSME if both diabetes was present and they were free of DR and CSME at baseline. LALES categorized incidence by 1st eye (both eyes free of ocular disease at baseline) and 2nd eye (only one eye free of ocular disease at baseline). Definite diabetes was defined as either having 1) a self-reported history of diabetes or 2) levels of hemoglobin A1C (HbA1c) and random blood glucose of at least 7.0% and 200 mg%, respectively. All participants underwent a standardized ophthalmic examination. DR and CSME were detected by grading of stereoscopic fundus photographs using the Modified Airlie House classification scheme. Chi-square and trend tests were done to assess differences in incidence when stratifying by age, gender, HbA1c, and duration of diabetes (defined at baseline).
Results: :
Of the 533 participants with diabetes who were seen at follow up and were free of retinopathy at baseline, 529 had gradable photographs. The four-year incidence of DR in the 1st eye, 2nd eye, and 1st or 2nd eye were 28.1% (112/399), 53.1% (69/130), and 34.2% (181/529), respectively. Significant increases in incidence were seen with increasing age (p=0.01), HbA1c (p<0.001), and duration of diabetes (p<0.001). Of the 717 individuals at risk for CSME, 711 had gradable photographs. Incidence of CSME in the 1st eye, 2nd eye, and 1st or 2nd eye were 6.2% (41/657), 16.7% (9/54), and 7.0% (50/711), respectively. Significant trends were seen across increasing duration (p=0.002) and HbA1c subgroups (p<0.001), but not age (p=0.658). No gender differences in incidence were found for DR and CSME.
Conclusions: :
Four-year incidence of DR and CSME in Latinos is high. Results indicate that this may be due to poor glycemic control (measured by HbA1c) and/or longer duration of diabetes among Latinos. High incidence of DR and CSME suggest the need for conducting epidemiologic studies to examine factors associated with long-term complications in Latinos.
Keywords: diabetic retinopathy • clinical (human) or epidemiologic studies: prevalence/incidence • clinical (human) or epidemiologic studies: risk factor assessment