Anti-VEGF treatment for wet AMD has changed the disease paradigm for the better, no doubt. However, case reports exist warning of the rare possibility of ischemic optic neuropathy (ION). Although researchers have yet to uncover the underlying pathogenesis of the association between anti-VEGF and the risk of subsequent ION, a new population-based study from Taiwan now provides some guidance, suggesting the number of injections is linked to the risk.

The researchers included the records of neovascular AMD patients treated with anti-VEGF between 2007 and 2013, numbering a total of 77,210 patients. They divided them into three groups based on the number of injections: level 1 had fewer than 10 injections (26,520 patients), level 2 had between 10 and 15 (38,010 patients), while level three had more than 15 (12,680).

The team followed patients for approximately 3.5 years and found 0.23% of the entire study group developed ION—0.15% of level one patients, 0.26% of level two and 0.32% of level three. They noted that the cumulative hazard ratios of ION rose significantly with the number of injections. After adjusting for age, sex and comorbidities (such as diabetes, glaucoma, hypertension, hyperlipidemia and ischemic heart disease), the hazard ratios for ION were 1.91 and 2.20 for second and third level patients compared with first level patients.

“Our recommendation is not to oppose treatment or change the protocols, which require more time and additional studies,” the researchers concluded in their paper.

“At present, our study is simply a reminder for ophthalmologists to check optic nerve changes following anti-VEGF injections among neovascular AMD patients, especially those who receive a high number of injections.” 

Chen Y-Y, Chou P, Huang Y-F, et al. Repeated intravitreal injections of antivascular endothelial growth factor in patients with neovascular age-related macular degeneration may increase the risk of ischemic optic neuropathy. BMC Ophthalmol. December 30, 2019. [Epub ahead of print].