STOCKHOLM: A retrospective analysis of real-world data found that greater improvements in visual acuity were associated with receiving more anti-VEGF injections over a 5-year period for the treatment of macular edema caused by retinal vein occlusion (RVO). The study team concluded that this demonstrated the need for more long-term therapies and continued observation to preserve vision.
The results were presented at the 2024 American Society of Retina Specialists (ASRS) Annual Meeting.
According to Christiana Dinah, MBBS, MRes, London North West University Healthcare NHS Trust, London, UK, RVO is the second most common retinal vascular disease. RVO is a significant cause of visual impairment. Future projections indicate that its prevalence will increase due to an ageing population and an increase in cardiovascular disease.
“We know that there is very little data on the long-term outcomes of treatment of retinal vein occlusion“Our study analyzed anti-VEGF treatment patterns for macular oedema secondary to retinal vein occlusion in the UK and visual outcomes in this population over a 5-year period.”
The study
The researchers analyzed Medisoft electronic medical record data from 2013 to 2023, collected by 16 organizations in the U.K. National Health Service, for this retrospective, observational analysis.
Patients with macular edema due to hemi-RVO (HRVO), central RVO (CRVO), or branch RVO (BRVO) were included in the study. Inclusion criteria: patients had to have their visual acuity assessed at the time of the index injection, at least one intravitreal anti-VEGF injection had to be administered at or after diagnosis, and follow-up had to occur for three to sixty months after the index injection.
The analysis included 3,511 eyes of 3,465 patients with OBRV and 3,568 eyes of 3,514 patients with OBRV or OBRV. After index injection, more than half (57.4%) of eyes were observed for at least 24 months and 19.1% were observed for up to 60 months.
During the first half of the year, eyes with BRVO received an average of 4.3 anti-VEGF injections, while eyes with CRVO and HRVO received an average of 4.1 injections. This suggests a high treatment frequency at this early stage.
In contrast, BRVO eyes received a mean of 2.1 injections, while CRVO and HRVO eyes received a mean of 2.0 injections over the next six months. The mean number of injections decreased over time. BRVO and C/HRVO eyes received 3.4 and 3.2 injections, respectively, during the second year of follow-up, and 2.5 and 2.4 injections during the fifth year.
More is better
Changes in visual acuity were also monitored; three months after injection, there was a mean improvement of 11.1 letters for OBRV and 13.8 letters for OBRV and OBRV. At sixty months, the mean improvement had fallen to 8.3 and 7.0 letters, respectively.
“We saw rapid and substantial visual gain within 3 months,” she said. “Until about 18 months ago, when the gain started to decline, it remained stable. By year 5, the visual gain in the CRVO group is at least half of what it was at baseline.”
The researchers observed a smaller increase in visual acuity in patients who received fewer injections. The average changes in the groups who received low injections (< 4), moyennes (4-8) et élevées (> 8) at 12 months revealed the following trend: According to Dinah, there is a correlation between a higher number of injections and better visual outcomes. This underlines the importance of persistent treatment to maximize vision recovery.
Clear results with a caveat
One of the major limitations of the study, according to Yasha S. Modi, MD, a vitreoretinal surgeon at New York University in New York City who moderated the Retinal Vascular Disease Symposium 2 panel at ASRS24, is the loss of follow-up data.
He questioned how selection bias affected the interpretation of the results, saying: “When you have data on 3,500 patients initially, and then after 60 months you have only 500, you only have about 15% of your original data set.”
“We have to take these results with that caveat,” Dinah said. The study results, she added, should be interpreted in light of the fact that randomized controlled trials have shown that patients who receive injections every 4 to 8 weeks, rather than every 3 months, experience greater visual gains. “This suggests that the number of injections matters and that we need longer-lasting treatments to maintain the initial vision gain.”
