Aflibercept in clinical practice; visual acuity, injection numbers and adherence to treatment, for diabetic macular oedema in 21 UK hospitals over 3 years

Introduction: Randomised controlled trials provide evidence that a treatment works. Real world evidence is required to assess if proven treatments are effective in practice. Method: Retrospective data collection on patients given aflibercept for diabetic macular oedema over 3 years from 21 UK hospitals: visual acuity (VA); Index of multiple deprivation score (IMD); injection numbers; protocols used, compared as a cohort and between sites. Results: Complete data: 1742 patients (from 2196 eligible) at 1 year, 860 (from 1270) at 2, 305 (from 506) at 3 years. The median VA improved from 65 to 71, 70, 70 (ETDRS letters) at 1, 2 and 3 years with 6, 9 and 12 injections, respectively. Loss to follow-up: 10% 1 year, 28.8% at 3. Centres varied: baseline: mean age 61-71 years (p < 0.0001); mean IMD score 15-37 (p < 0.0001); mean VA 49-68 (p < 0.0001). Only four centres provided a loading course of five injections at monthly intervals and one 6. This did not alter VA outcome at 1 year. Higher IMD was associated with younger age (p = 0.0023) and worse VA at baseline (p < 0.0001) not total number of injections or change in VA. Lower starting VA, higher IMD and older age were associated with lower adherence (p = 0.0010). Conclusions: The data showed significant variation between treatment centres for starting age, VA and IMD which influenced adherence and chances of good VA. Once treatment was started IMD did not alter likelihood of improvement. Loading dose intensity did not alter outcome at one year.