Abstract
Purpose: :
To describe the relationship of change in retinal arteriolar and venular diameters to the incidence and progression of diabetic retinopathy (DR) and incidence of proliferative DR (PDR) and macular edema (ME) in persons with diabetes mellitus (DM) in the WESDR.
Methods: :
There were 610 persons with type 1 DM and 465 persons with type 2 DM who participated in a baseline and follow-up examinations in 1980-82, 1984-86 and 1990-92, had DR graded from 30° stereoscopic color fundus photos using the Airlie House Classification scheme and had computer-assisted measurements of the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE).
Results: :
Over the first 4-year period of the study, the mean change in CRAE and CRVE was -0.45 µm and 2.41 µm, respectively. The 6-year incidence and progression of DR by 2 or more steps and the incidence of PDR and ME from 1984-86 to 1990-92 were 58%, 53%, 17%, and 14%, respectively. In multivariate analyses, while controlling for duration of DM and changes in HbA1c, mean arterial blood pressure, DR severity and proteinuria, an increase of 5% in CRAE from 1980-82 to 1984-86 was associated (odds ratio; 95% confidence interval) with an increase in the 6-year progression of DR (1.16; 1.02-1.33) and the incidence of ME (1.19; 1.00-1.41) while a 5% increase in CRVE controlling for the above variables was associated with the progression of DR (1.18; 1.04-1.34). Neither changes in CRAE nor CRVE were associated with the 6-year incidence of retinopathy or PDR.
Conclusions: :
These data show that independent of DR severity level, glycemic control and other factors, widening of the retinal venules and arterioles are associated with the progression of DR. Therefore, including change in retinal vessel diameters is likely to improve the ability to predict change in the severity of DR.
Keywords: diabetic retinopathy • clinical (human) or epidemiologic studies: outcomes/complications • clinical (human) or epidemiologic studies: risk factor assessment