Observation versus Treatment in Diabetic Macular Edema with Very Good Visual Acuity – The OBTAIN study

Purpose : To describe and compare the functional and anatomical 12-month outcomes of untreated and treated diabetic macular edema (DME) in eyes with very good baseline visual acuity (VA) in a real-world setting. Methods : To be included in this retrospective, multicenter, observational cohort study, eyes were required to have DME with baseline visual acuity (VA) ≤ 0.1 logMAR (≥ 20/25 Snellen) and central subfield thickness (CST) > 250 µm with intra- and/or subretinal fluid seen on optical coherence tomography. Patients charts were reviewed for demographic data and baseline characteristics, prior DME treatment, VA and CST at baseline, month 3, 6, 9, 12, and DME treatment during the 12-month follow-up. Main outcome measures were change in VA and CST at 12 months in treaed vs. observed eyes. Statistical analyses were performed by generalized estimating equations procedure. Results : A total of 249 eyes from 211 patients were included, of which 155 eyes were treated during follow up and 94 eyes were observed. The majority of eyes maintained vision (VA loss < 5 letters or VA gain) at 12 months (treated: 58.1%; observed: 73.4%). In the vast majority of observed eyes (63/73 eyes, 86.3%) with stable VA within the first 6 months, VA was maintained throughout the follow-up (-0.1 ± 3.8 letters, p=0.889). In 54 of 147 eyes (36.7%), that were initially observed, a VA loss ≥ 5 letters within 6 months was experienced. Within those eyes, further observation (n=21) led to worse visual outcome than treatment (n=33) (-4.2 vs. -7.8 letters, p=0.013). In eyes in which treatment was initiated at baseline (n=102), intensive treatment (8-12 anti-VEGF injections during the 12 months follow up) led to CST improvement (-85.9 vs.+11.3 µm, p=0.003), but there was no significant difference in visual acuity (-0.3 vs. -1.8 letters, p=0.137) compared with observation. Conclusions : In a real-world setting, the majority of DME patients with very good VA maintained vision at 12 months, regardless of whether the DME was treated or not. This study supports close observation of eyes with DME and very good VA with consideration of treatment when a one line drop in vision is observed.