Treat-and-extend bevacizumab for neovascular age-related macular degeneration: the importance of baseline characteristics

Abstract

Purpose: To evaluate the factors affecting visual and anatomical outcomes and the number of intravitreal bevacizumab injections required in the treatment of neovascular age-related macular degeneration using a treat-and-extend regimen.

Methods: Retrospective consecutive case series. The charts of subjects treated with intravitreal bevacizumab for neovascular age-related macular degeneration using a treat-and-extend regimen over a 12-month period were reviewed. The key variables explored were patient age, phakic status, posterior vitreous detachment status, baseline best-corrected visual acuity (BCVA), baseline central macular thickness (CMT), and type of chorodial neovascularization. The primary outcome measures were improvement in BCVA of 3 logMAR lines or more, maintenance of BCVA within 3 logMAR lines of baseline, number of intravitreal injections delivered over a 12-month period, and final CMT on optical coherence tomography.

Results: A total of 230 eyes met the criteria. Mean presenting BCVA was Snellen 20/55 (0.44 logMAR) and mean final BCVA was Snellen 20/44 (0.35 logMAR) (P < 0.001). A total of 23.5% (95% confidence interval [CI], 18.5-29.4%) of the subjects demonstrated an improvement in BCVA of 3 or more logMAR lines, whereas 96.5% (95% CI, 93.3-98.2%) of the subjects lost fewer than 3 logMAR lines. Mean CMT on optical coherence tomography changed from a baseline average of 373.1 μm (95%CI, 360.3-386.1 μm) to a final average of 305.5 μm (95% CI, 290.0-316.0 μm). The average number of injections during the 12-month period was 9.2 (95% CI, 9.0-9.4). Posterior vitreous detachment was associated with fewer injections on univariate and multivariate analysis (8.7 injections in the posterior vitreous detachment group versus 9.8 in the non-posterior vitreous detachment group, P < 0.001). Patients with poorer presenting BCVA and greater baseline CMTs were more likely to demonstrate a 3 or more logMAR line improvement in BCVA. Thinner final CMTs were independently associated with thinner presenting CMTs and fewer injections.

Conclusion: Favorable visual and anatomical outcomes may be achieved with intravitreal bevacizumab in the treatment of neovascular age-related macular degeneration using a treat-and-extend regimen. Our study suggests that posterior vitreous detachment may play a role in the efficacy of intravitreal bevacizumab during the treatment of neovascular age-related macular degeneration.