Visual/anatomical outcome of diabetic macular edema patients lost to follow-up for more than 1 year.

To investigate the visual/anatomical outcome of diabetic macular edema (DME) patients lost to follow-up (LTFU) for more than 1 year during intravitreal anti-VEGF treatment. A retrospective review of 182 treatment-naïve DME patients was performed. Among them, we identified patients LTFU for more than 1 year during anti-VEGF treatment. Visual acuity and anatomic outcomes at the first visit, last visit before being LTFU, return visit, and after re-treatment were analyzed and compared with those of DME patients with regular follow-up. Patients who had continuous follow-up visits were assigned to the control group. Sixty patients (33%) with DME were LTFU for more than 1 year during anti-VEGF treatment. Multivariate analysis revealed that the ratio of male (p = 0.004), diabetes mellitus (DM) duration less than 5 years (p = 0.015), and poor early anatomic response (p = 0.012) were higher compared to the control group. Eighteen patients returned to the clinic and received re-treatment. After re-treatment with anti-VEGF, central subfield thickness (CST) was significantly improved to the CST of before LTFU. However, visual acuity did not recover to the level before LTFU (0.63 ± 0.26 vs. 0.45 ± 0.28, p = 0.003). About thirty percent of DME patients were LTFU for more than 1 year. Permanent visual loss was observed in these LTFU patients. Patients with a high risk of LTFU such as male, early DM, and poor response after initial injections should be treated more aggressively to improve the visual outcomes.