Abstract
Purpose:
Determine the long-term real-world effectiveness of intravitreal anti-VEGF therapy in patients with newly diagnosed diabetic macular edema (DME) treated in clinical practice.
Methods:
Patients with DME were identified from Kaiser Permanente’s 350,000 patients with diabetes mellitus treated between 2008 and 2013. Patients were eligible if they had a new diagnosis of DME and received an intravitreal bevacizumab injection within 12 months of initial diagnosis. Patients with AMD or vein occlusion were excluded. Visual acuity (VA), number of intravitreal injections and patient characteristics were abstracted from the electronic record. The main outcome measure was change in VA at 3, 6, 9, 12, and 24 months of follow-up. Snellen visual acuities were converted to ETDRS letter equivalents using a published algorithm. Missing VA data was imputed using the last observation carried forward (LOCF) method.
Results:
A total of 366 patients met all inclusion criteria and had 2 years of follow-up after their first bevacizumab injection. At baseline, 20.8% of patients had VA better than or equal to 20/40 and 12.3% had a VA worse than 20/200. In this cohort, patients had a mean of 3.1 injections (range, 1-17) during the 2-year follow-up. Mean VA improvement was 4.1 letters at 12 months, and 4.9 letters at 24 months. Only 29.8% of patients (ETDRS score of ≤ 70 at baseline, N = 325) demonstrated > 3 lines of improvement from baseline in their vision; while 12.3% of all patients reported > 3 lines of vision loss from baseline.
Conclusions:
The current study is the largest long-term US clinical practice based study of anti-VEGF use for diabetic macular edema. The frequency of injection was low, with less average VA improvement than in anti-VEGF trials. Significant visual acuity improvement was achieved in about 30% of patients. There is opportunity for greater vision improvement with more frequent injections or treatments with longer duration of action. Future studies will look at more recent data using other agents.