At the ASRS 39th Annual Scientific Meeting, Dr W. Lloyd Clark discusses retinal nonperfusion and leakage areas when managing patients with nonproliferative diabetic retinopathy in context of the results of the PANORAMA study.
Retinal nonperfusion and leakage areas are important variables to consider when managing patients with nonproliferative diabetic retinopathy (NPDR), according to the results of the PANORAMA study. The data showed that increases in the areas of those characteristics are associated with increased rates of centre-involved diabetic macular oedema (DMO) and vision-threatening complications in the sham-treated group. Dr W. Lloyd Clark from Palmetto Retina, West Columbia, SC, presented the results on behalf of the PANORAMA investigators.
The goal of the PANORAMA study was to identify the factors that increase the risk of complications in patients with NPDR to aid in treatment choices. In this trial, the patients received intravitreal aflibercept injections (Eylea, Regeneron Pharmaceuticals) or sham treatment through the 100-week study course.
The PANORAMA study included patients with moderately severe to severe NPDR based on the Diabetic Retinopathy Severity Scale (DRSS) 47–53 without baseline DMO. After receiving initial loading doses, 135 patients were randomized to receive 2-mg intravitreal aflibercept injections every 16 weeks, and 133 patients were randomized to the same dose every 8 weeks (with as-needed dosing in year 2 in 134 patients); 133 patients were randomized to sham treatment.
For the post-hoc analysis, the data from the 2 groups treated with intravitreal aflibercept injections were combined. The baseline nonperfusion areas in mm2 were analyzed in 4 groups: group 1, without nonperfusion (201 patients); group 2, >0–≤0.24 (52 patients); group 3, >0.24–≤0.66 (53 patients); and group 4, >0.66 (51 patients).
The baseline leakage area in mm2 was analyzed by quartile: quartile 1, ≤10.20 (98 patients); quartile 2, >10.20–≤19.76 (97 patients); quartile 3, >19.76–≤30.41 (97 patients); and quartile 4, >30.41 (97 patients).
Dr Clark reported, “Higher proportions of sham-treated patients, compared with those treated with aflibercept injections, had centre-involved DMO or vision-threatening complications as the baseline nonperfusion or leakage areas increased. The risk of centre-involved DMO increased with the baseline nonperfusion area (per 1-mm2 increase) with sham treatment (hazard ratio, 1.32; 95% confidence interval [CI], 1.04, 1.67), but this was not the case with the injections (hazard ratio, 0.95; CI, 0.68, 1.33).”
He also reported that similar results were seen with the risk of vision-threatening complications: sham, hazard ratio, 1.44; CI,1.08, 1.92; and injections, hazard ratio, 1.10; CI, 0.89, 1.38.
The risks of centre-involved DMO with increasing leakage area (per 1-mm2 increase) were 1.02 (CI, 0.99, 1.05) with sham and 1.03 (CI, 1.00, 1.07) with injections. The risks of vision-threatening complications were 1.08 (CI, 1.04, 1.12) with sham and 1.00 (CI, 0.96, 1.04) with injections. Sham treatment but not injections was associated with decreased improvement in the DRSS by 2 or more steps and increased worsening of the DRSS by 2 or more steps with increasing baseline nonperfusion and leakage areas; the finding was not significant for the nonperfusion area.
Dr Clark concluded, “Increasing baseline retinal nonperfusion and leakage areas were associated with increased rates of centre-involved DMO or vision-threatening complications in the sham group, and this was not observed in the patients treated with intravitreal aflibercept injections. Retinal nonperfusion and leakage areas are important variables to consider when managing patients with NPDR.”