DIGOXIN DOES NOT ACCELERATE PROGRESSION OF DIABETIC-RETINOPATHY

OBJECTIVE- To test the hypothesis that digoxin, an inhibitor of Na+-K-ATPase activity, accelerates the progression of diabetic retinopathy. RESEARCH DESIGN AND METHODS- We compared the incidence and risk of re tinopathy in 120 digoxin-taking vs. 867 non-digoxin-taking diabetic pa rticipants in the Wisconsin Epidemiologic Study of Diabetic Retinopath y (WESDR) and in 117 digoxin-taking vs. 1,883 non-digoxin-taking diabe tic subjects in the Early Treatment Diabetic Retinopathy Study (ETDRS) . In both studies, retinopathy was detected by grading stereoscopic co lor photographs using the modified Airlie House classification scheme, and a two-step difference in baseline retinopathy grade was considere d significant. RESULTS- After controlling for other risk factors, we f ound no statistically significant association with either dr-year inci dence of retinopathy (WESDR) or progression of retinopathy (WESDR and ETDRS) in patients laking digoxin at baseline compared with those not taking digoxin. CONCLUSIONS- These data suggest that digoxin therapy d oes not adversely affect the course of diabetic retinopathy.