Some patients with both age-related macular degeneration (AMD) and pseudoexfoliation (PXF) may have sustained IOP elevations after intravitreal anti-VEGF treatments, new research in the Journal of Glaucoma suggests.

The study specifically found 18.6% of patients with the coexisting conditions had sustained elevated IOP after approximately 19 injections, which reflected the cumulative effect of anti-VEGF therapy on IOP, the researchers note.

The team of Turkish researchers compared the long-term impact of intravitreal ranibizumab and intravitreal bevacizumab therapies on IOP in patients with and without PXF.

The investigators reviewed data from 412 eyes of 206 patients diagnosed with unilateral neovascular AMD. The subjects were treated with ranibizumab or bevacizumab and followed for at least six months. The study included 70 treated and 70 untreated fellow eyes of 70 patients with bilateral PXF syndrome, and 136 treated and 136 untreated fellow eyes of 136 patients without PXF syndrome. The investigators considered demographic information, clinical findings, total number of injections and IOP at each visit. Patients were approximately 78 years old and were followed up at about 29 months. Subjects in the study underwent approximately 16 injections.

Sustained elevation of IOP was defined as either IOP greater than 21mm Hg or a 5mm Hg or more increase in IOP from baseline for at least two consecutive visits.

The mean baseline and final IOP in the treated eyes were 14.8mm Hg and 16.5mm Hg, respectively. Researchers observed a higher incidence of sustained IOP elevation and higher final IOP in PXF eyes that received bevacizumab compared with the other groups. Additionally, seven patients required anti-glaucomatous treatment.

The study also reported an increased odds ratio (4.90) of sustained elevated IOP in PXF-positive eyes compared with the healthy eyes in the control group.

The accumulation of both PXF material and bevacizumab particles on the trabecular meshwork should be further investigated, the investigators noted in their paper.