Purpose: The purpose of this study is to evaluate the effect of complement factor H (CFH) Y402H CC and TT polymorphisms on treatment response to intravitreal ranibizumab injection in patients with wet age-related macular degeneration (AMD).
Methods: One hundred ninety-three patients with choroidal neovascularization (CNV) secondary to AMD who were monitored for at least 6 months of follow-up, and with at least three ranibizumab injections, were included in the study. At the final examination, an increase in visual acuity (VA) of five letters or more compared to the initial VA was regarded as a good response, and a decrease in VA of five letters or more compared to the initial VA was evaluated as a poor response. A genetic examination was performed with a PCR melting curve analysis. In the statistical evaluation, SPSS version 18 software was used.
Results: The mean age of the patients was 71.01 (55-86) years, the mean follow-up was 13.34 (6-36) months, and the mean number of injections was 4.02 (3-15). There were 96 patients in the good response group (Group 1) and 97 patients in the poor response group (Group 2). The initial VA in Group 1 was 41.34 (10-64) letters, the initial central macular thickness (CMT) was 213.40 (126-494) µm, and the initial lesion width was 3760 (1430-6430) µm. The initial VA in Group 2 was 52.89 (26-82) letters, the initial CMT was 257.60 (115-882) µm, and the initial lesion width was 4460 (1000-7650) µm. There was no statistically significant difference between the two groups in terms of the initial VA and CMT (p=0.094, p=0.083). However, there was a statistically significant difference between the groups in the width of the initial lesion (p=0.003). In Group 1, 15 CC, 30 TT, and 51 TC alleles were found, and in Group 2, 49 CC, two TT, and 46 TC alleles were found, and the distribution was significantly different between the two groups (p=0.012). The change in the distribution of genotypes was not associated with either the lesion size or VA (p=0.841). Fibrosis developed in 12 patients who were all poor responders.
Conclusions: CFH Y402H CC accompanied a poor response, and TT accompanied a good response in this series of patients with AMD undergoing ranibizumab therapy.