Delayed follow-up of medical retina patients due to COVID-19: impact on disease activity and visual acuity.

ABSTRACT

PURPOSE: The coronavirus pandemic has prompted unprecedented delays to treatment with anti-VEGF intravitreal injections due to the need to reduce hospital attendances and prioritise the patients at highest risk of vision loss. This study aims to quantify the effect of these delays on visual acuity (VA) outcomes and optical coherence tomography (OCT) features for patients receiving treatment for neovascular age-related macular degeneration (nAMD), retinal vein occlusions (RVO) and diabetic macular oedema (DMO) and correlate to the Royal College of Ophthalmologists guidelines (RCOphth). METHODS: A retrospective data analysis of an electronic medical record was performed on a random sample of eyes receiving anti-VEGF injections for nAMD, RVO or DMO. Data collected included age, sex, reason for injection, number of weeks delay if > 8 weeks from that planned, VA at baseline and follow-up and the OCT features, if delayed. For those eyes not delayed, a visual acuity at 20 weeks was recorded to provide a control group. RESULTS: A sample of 981 eyes (858 patients) were analysed. There was a delay in review of 8 weeks or more in 39.6% of patients of which 30.4% had since returned for review (28.4% nAMD, 37.6% RVO and 30.0% DMO). There was no demographic difference identified between the delayed and non-delayed patients; however, the delayed group was significantly more likely to have better vision in their non-treated eye (p = 0.0003). A statistically significant difference was found in the change in VA between the delayed and the not-delayed group for eyes with nAMD (p = 0.001) but not for RVO or DMO. For the delayed group, mean CMT increased by 33 and 100 µm, respectively, for nAMD and RVO and decreased by 7.8 µm for DMO. The VA of 89.7% of DMO eyes returned to baseline, compared to 74.6% and 76.9% of nAMD and RVO eyes. CONCLUSION: The RCOphth guidance to prioritise intravitreal injections for nAMD over DMO appears appropriate in this cohort but not for RVO. Eyes with nAMD experienced the greatest loss of vision with treatment delay, and nAMD and RVO eyes were less likely to return to baseline on restarting treatment.