Purpose
The purpose of the study was to evaluate temporal changes in age- and sex-stratified incidence rates of retinal vein occlusion (RVO) commenced in anti-vascular endothelial growth factor (anti-VEGF) treatment, proportion of patients remaining in active anti-VEGF therapy over time, and to develop a forecasting model for future number of patients with RVO in active anti-VEGF therapy.

Methods
This was a registry-based study of patients with RVO in the Capital Region of Denmark from commenced in anti-VEGF therapy from 1 January 2007 to 30 June 2022. Census data were extracted from Statistics Denmark for incidence rate analyses and forecasting data of future demographics.

Results
A total of 2641 patients with RVO were commenced in anti-VEGF therapy, of which 2192 were later discontinued. Number of patients rose dramatically during the first years of introduction of anti-VEGF therapy, after which growth was slower and followed the demographic changes. Trend analyses revealed that the COVID-19 epidemics impacted with fewer referrals and more aggressive discontinuation practices. Annual incidence of RVO in 2012–2021 was 13.1 per 100 000 (95% CI: 12.6–13.6 per 100 000). Proportion of patients with RVO remaining in active anti-VEGF treatment was 55.0%, 40.1%, 30.8% and 12.1% after Years 1, 2, 3 and 8, respectively. According to our forecast, number of patients with RVO in active anti-VEGF therapy will grow slowly but continually at least until year 2035.

Conclusion
Our study reports incidence rates and provides prognostic modelling of number of patients with RVO in anti-VEGF therapy.