Treating diabetes-related eye disease early might slow its progression to severe disease, but it does not improve visual acuity compared with treating the condition once developed, according to a study published in JAMA.
Anti-vascular endothelial growth factor (anti-VEGF) has been shown to decrease the risk of vision loss from diabetic retinopathy significantly. However, eye specialists are unsure when treatment with anti-VEGF should start to achieve the best long-term outcome.
Dr. Raj Maturi and colleagues conducted a study to find out whether using the medication aflibercept to treat patients with nonproliferative diabetic retinopathy (NPDR) and good vision would reduce disease progression and improve long-term visual acuity compared to only treating if the disease worsens.
The study included 328 participants, with 399 study eyes (both eyes in some participants met the enrollment criteria; others only had one study-eligible eye). The researchers randomly assigned the participants to receive injections with preventive anti-VEGF (aflibercept) or a placebo solution, then followed them for up to four years.
Preventive therapy was injected into 200 eyes, while 199 were given a placebo. The preventive therapy was given every four months, except in cases where the NPDR improved to only mild disease.
At the end of the study, the researchers found that the group who received the anti-VEGF had less structural damage to the eye than those who received the placebo. In addition, they found that disease progression was lower in the group receiving anti-VEGF injections compared with the placebo group (37% vs 54%). However, the drug did not do much to prevent vision loss.
“We expected early treatment to prevent progression of diabetic retinopathy, but even with preventative injections, about one-third of eyes developed vision-threatening complications,” said Adam Glassman, who directs the DRCR Retina Network coordinating center.
According to one of the senior authors, the study findings indicate that the benefit of anti-VEGF treatment may not be worth the “risk and inconvenience” of repetitive visits for preventive NPDR injections.
Source: NIH Newsletter