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 retinopathy in 120 digoxin-taking vs. 867 non-digoxin-taking diabetic participants in the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) and in 117 digoxin-taking vs. 1,883 non-digoxin-taking diabetic subjects in the Early Treatment Diabetic Retinopathy Study (ETDRS). In both studies, retinopathy was detected by grading stereoscopic color photographs using the modified Airlie House classification scheme, and a two-step difference in baseline retinopathy grade was considered significant. RESULTS- After controlling for other risk factors, we found no statistically significant association with either dr-year incidence 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 does not adversely affect the course of diabetic retinopathy.