Sustained Elevation of IOP Following Intravitreal Injections of Bevacizumab
in Neovascular AMD
The use of intravitreal anti-vascular endothelial growth factor (VEGF) agents
in general, and of bevacizumab (Avastin) in particular, has become the common first-line
treatment of neovascular age-related macular degeneration (AMD). Several reports addressed
the possible elevation of intraocular pressure (IOP) following intravitreal injection of
anti-VEGF. The authors of the following Israeli retrospective cohort study aimed to determine
the prevalence of sustained IOP elevation following intravitreal bevacizumab injections
for neovascular AMD and to identify possible risk factors for the development of increased IOP.
In this study, they included 174 consecutive patients (201 eyes) receiving intravitreal
bevacizumab (1.25 mg/0.05 ml) as treatment for neovascular AMD. The authors reviewed the records
of the study patients for age, gender, history of glaucoma, phakic status, IOP levels, length
of follow-up, total number of injections, intervals between injections and IOP management in eyes
that exhibited IOP elevation. Sustained IOP elevation was defined as IOP ≥22 mmHg and a change
from baseline of ≥6 mmHg recorded on at least two consecutive visits and lasting ≥30 days.
The study authors identified risk factors for an IOP increase from the association between the
studied variables and IOP elevations.
They found sustained IOP elevation in 22 of 201 eyes (11%) and they noted that increased IOP
was controlled with topical medications in all eyes. Among the variables studied, only male gender
[OR = 3.1, 95% CI (1.1, 8.5) p=0.029] and length of interval between injections less
than eight weeks [OR = 3.0, 95% CI (1.1, 7.9), p=0.028] emerged as risk factors for
IOP elevation in a multivariable model. The prevalence of IOP elevation was significantly higher
when the interval between injections was less than eight weeks than when it was eight or more
weeks (17.6 and 6%, respectively, p=0.009). Pre-existing glaucoma was not associated with
IOP elevation (p=0.9).
Sustained IOP elevations can occur in normotensive eyes undergoing intravitreal bevacizumab
treatment for neovascular AMD. This phenomenon was related to shorter intervals between injections,
with eight weeks being taken as the cut-off point. AMD eyes that receive intravitreal
bevacizumab injections need to be monitored for IOP changes, especially those in which the
intervals between injections are less than eight weeks.