Factors influencing macular atrophy growth rates in neovascular age-related macular degeneration treated with ranibizumab or aflibercept according to an observe-and-plan regimen.

BACKGROUND/AIMS: To investigate the factors associated with macular atrophy (MA) growth rates in neovascular age-related macular degeneration treated with either ranibizumab or aflibercept.

METHODS: We obtained data from two identical prospective studies using ranibizumab or aflibercept under observe-and-plan variable dosing regimens. We analysed eyes that presented MA within 2 years. After applying square root transformations to MA sizes, we calculated MA growth rate from baseline to the year 2 endpoint and used univariate and multivariate analyses to detect ocular and treatment factors associated with the MA growth rate.

RESULTS: Included were 109 eyes from 101 patients (mean age 80.6 years). The mean square-root-transformed MA growth rate was 0.54±0.34 mm/year. The univariate analyses revealed that MA growth rates were significantly associated with lower baseline visual acuities (p=0.001) and thicker subretinal tissue complexes (p=0.006) and near-significantly associated with the presence of pigment epithelium detachment (p=0.057) and choroidal neovascularisation subtypes (p=0.069). Our multivariate analysis confirmed the significance of lower baseline visual acuities (p=0.008) and pigment epithelium detachments higher than 200 µm (p=0.035). Furthermore, MA growth rates in neovascular eyes significantly correlated with MA growth rates in non-neovascular fellow eyes (n=61; p=0.003).

CONCLUSION: MA growth rates were associated with ocular factors in the study eyes and the fellow eyes but not with the drug or the number of injections within this variable dosing regimen.