Predictors of Functional and Anatomic Outcomes in Patients with Diabetic Macular Edema Treated with Ranibizumab

ObjectiveTo investigate baseline predictors of month 24 best-corrected visual acuity (BCVA) and central foveal thickness (CFT) in patients with diabetic macular edema (DME) treated monthly with ranibizumab or sham.DesignPost hoc analysis of DME patients in 2 identical phase 3 studies.ParticipantsPatients randomized to ranibizumab (n = 502) or sham (n = 257).MethodsMultivariate regression on predictors with P < 0.20 in univariate logistic regression using backward selection to retain predictors with P < 0.05.Main Outcome MeasuresPatient characteristics correlating with month 24 BCVA in Early Treatment Diabetic Retinopathy Study letter score ≥70 (20/40) or ≤50 (20/100), gain or loss from baseline BCVA of ≥15, or CFT ≤250 μm.ResultsBaseline predictors of BCVA ≥20/40 in ranibizumab-treated patients were good BCVA, submacular fluid, no cardiovascular disease, no scatter photocoagulation, and male gender, whereas in sham-treated patients, they were mild increase in CFT, presence of hard exudates in center subfield, and absence of renal disease. Predictors of improvement in BCVA letter score ≥15 in ranibizumab-treated patients were poor BCVA, submacular fluid, young age, and short diabetes duration, and those in sham-treated patients were poor BCVA, young age, and mild increase in CFT. Predictors of resolution of edema (CFT ≤250 μm) in ranibizumab-treated patients were mild foveal thickening and prominent subfoveal fluid, and those in sham-treated patients were poor BCVA, mild foveal thickening, and statin usage. Month 24 BCVA ≤20/100 was predicted by poor baseline BCVA in ranibizumab-treated patients, and by poor baseline BCVA, large intraretinal cystoid spaces, renal disease, and absence of hypercholesterolemia in sham-treated patients. Loss of BCVA ≥15 letters was predicted in sham-treated patients by submacular fluid, intraretinal cystoid spaces, and renal disease.ConclusionsPatients with DME and submacular fluid, intraretinal cysts, severe thickening, or renal disease respond poorly when untreated and respond well to ranibizumab treatment. Elimination of submacular fluid, intraretinal cysts, and severe thickening are important goals of DME treatment, and in patients with renal disease, treatment should be very aggressive, with a goal of eliminating all macular fluid.