Abstract
Purpose :
Metabolic alterations in diabetes can affect retinal blood flow. In this study, we investigate whether metformin use is associated with changes on retinal blood flow in diabetic retinopathy (DR) patients regardless of HbA1c level.
Methods :
This is a retrospective study of patients with longstanding type 2 diabetes. Patients with type 2 diabetes for more than 15 years were included. Patients were included if they never used metformin or used metformin for at least 5 years prior to onset of diabetic retinopathy. Patients without ophthalmic or primary care records were excluded. Fluorescein angiography records were reviewed and analyzed for artery, vein and capillary perfusion time, and the distribution of microaneurysms.
Results :
Eighty patients with diabetic retinopathy are included in the current analysis, 53 patients on metformin and 27 patients not on metformin. In the metformin group, there are 34, 3, and 16 of patients with mild, moderate, and severe diabetic retinopathy, while in the non-metformin group, there are 12, 3, and 12, respectively. Preliminary analysis of venous perfusion time in 15 patients with mild and moderate non-proliferative DR from each group revealed faster average venous filling time in metformin group comparing with that in non-metformin group (8.35 seconds versus 10.2 seconds). A gross estimate of microaneurysm distribution in 4 quadrants showed less microaneurysms in metformin group (3.26) versus in non-metformin group (3.86).
Conclusions :
These preliminary results suggest that metformin treatment may improve retinal venous perfusion, and reduce microaneurysm distributions in diabetic retinopathy patients.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.