The real-world effect of intravitreous anti-VEGF Drugs on IOP: An analysis using the IRIS registry

June 28, 2018

Elizabeth Atchison, MD, senior fellow, Rush University and Illinois Retina Associates Chicago, is the first-place honoree of the Ophthalmology Times Research Scholar Honoree Program. Below is her abstract: 

Elizabeth Atchison, MD, senior fellow, Rush University and Illinois Retina Associates Chicago, is the first-place honoree of the Ophthalmology Times Research Scholar Honoree Program. Below is her abstract: 

Purpose:

To identify differences in sustained intraocular pressure (IOP) after intravitreous injections of anti-vascular endothelial growth factor (VEGF) drugs in a real-world population.

Design:

Database study

Subjects:

Patients seeing an ophthalmic provider who is part of the database

Methods:

We identified patients who received only a single type of anti-VEGF medication (bevacizumab, aflibercept, or ranibizumab) by injection in their right eyes in the American Academy of Ophthalmology IRIS® Registry (Intelligent Research in Sight). Subgroups included patients with age-related macular degeneration (AMD) only, and patients who had not received an anti-VEGF injection for at least 1 year prior to the study. We also looked at those with more than 12, 18 and 25 injections for each of these 3 medications.  Outcomes included change in IOP from baseline, rate of clinically significant IOP increase and rates of glaucoma procedures. 

Results: 

23,873 patients were included in the study with a mean follow up of 681 days. 14,774 (62%) patients received bevacizumab, 4,138 (17%) received aflibercept and 4,961 (21%) received ranibizumab. The average number of injections was 6.9 for the All group, 7.8 for the AMD group, and 6.4 for the New group. By drug, there were an average of 6.1 bevacizumab, 8.9 aflibercept and 7.8 ranibizumab injections over the course of the study.

All agents in all groups showed a decrease in IOP from baseline ranging from zero to 0.52 mmHg (Figure 1). A sustained rise of at least 6 mmHg to an IOP over 21 mmHg occurred at a rate of 2.17%, 2.54% and 3.05% for aflibercept, ranibizumab and bevacizumab respectively (Figure 2). With increasing number of injections this proportion increased for the bevacizumab group only to a maximum of 9.5% for those with 25+ injections (Figure 2).  No similar increase was noted with the other drugs.

Looking at the proportion of patients undergoing a glaucoma procedure, the rate ranged from 0.7% to 1.5% over the course of the study for any number of injections (Table 1). This was roughly the same for those with over 25 injections (Table 1).  Overall, 53% of glaucoma procedures were laser trabeculoplasty.  In the 25 or more injections group the only procedure reported was laser trabeculoplasty (no incisional surgery).

Conclusion:

These analyses from real world data indicate that anti-VEGF intravitreous injections are overall associated with a small but statistically significant decrease in IOP over time.  However, a fraction of patients, ranging from 2-3%, experience a sustained clinically significant IOP rise with these drugs.  Bevacizumab when given over 25 times is associated with a sustained clinically significant pressure rise in an even higher percentage of patients, up to 9.5%.  Despite this, the rate of glaucoma procedures was low for all groups, drugs and number of injections and those with 25 or more injections had no incidences of incisional glaucoma surgery.

           Figure 2: Rate of clinically significant IOP increase by group, drug, and number of injections.

 

                Table 1: Glaucoma procedures by group, drug and number of injections.