Intraocular pressure trends following intravitreal injections of anti-VEGF agents for diabetic macular edema

Abstract

Purpose: To investigate the intraocular pressure (IOP) trends after intravitreal anti-vascular endothelial growth factor (VEGF) agents for diabetic macular edema (DME).

Methods: Retrospective chart review of 162 patients, (28-83 years, median 62), who received intravitreal bevacizumab (86.1% of eyes) and/or ranibizumab (13.9% of eyes) for DME. Data recorded included clinical findings, total number of injections received and IOP at each visit. IOP elevation was defined as an increase above baseline IOP by >5 mmHg or >20%, or an IOP of >24 mmHg on ≥2 consecutive visits or an IOP elevation requiring IOP lowering agents. Return to baseline IOP after two readings without treatment was defined as transient elevation.

Results: A total of 237 eyes of 162 patients were included at the time of this submission. The number of injections per eye ranged from 1-11 over a mean follow up of 16.14 months (range: 1-56; SD: 15.1). IOP elevation was observed in 17 (7.17%) eyes of 16 patients (IOP rise group). Transient elevation was recorded in 5 of the 17 eyes (2.11%). The majority of eyes (13/17 eyes [76%]) showedan IOP elevation above 20% from baseline, ranging from 16 to 32 mmHg (mean 22.41). Although there was no significant difference in the baseline IOPs betweenthe IOP rise group (mean 15.76 ; SD=3.18) vs. the rest of the eyes (mean 17.34 (SD= 3.48), p: 0.071), final IOP was significantly higher in the IOP rise group (mean 18.65 vs.16.81, p 0.047). None of the eyes required surgery, laser therapy, or systemic medications for IOP control. Only one eye required topical IOP lowering agents.Using univariate analysis, the total number of injections was higher in the IOP rise group (mean 4.76, SD 1.78) vs. 2.90, SD 2.09); p= 0.001, and a shorter interval between injections was significantly associated with IOP elevation (mean 3.89months, SD 3.02) vs. 8.18, SD 8.93); p< 0.001. Logistic regression analysis disclosed the total number of injections as the only variable significantly associated with post-injection IOP elevation (p= 0.012; 95% CI:1.06-1.64; Odds ratio: 1.32).

Conclusions: Our results suggest that IOP elevation following intravitreal anti-VEGF injections occurs in DME patients at a rate comparable to that reported for AMD patients. Eyes requiring a higher number of injections with shorter intervals between injections appear to be at increased risk.