Genetic and clinical factors associated with reticular pseudodrusen in exudative age-related macular degeneration

Reticular pseudodrusen (RPD) is considered to be a distinct entity from soft drusen and a risk factor for age-related macular degeneration (AMD). In the present study, we investigate the genetic and clinical factors associated with reticular pseudodrusen (RPD) in patients with exudative AMD, including polypoidal choroidal vasculopathy (PCV), typical neovascular AMD, and retinal angiomatous proliferation (RAP).

The presence or absence of RPD was studied among 408 patients with exudative AMD in at least one eye, and the clinical characteristics of those with RPD were investigated as well as genetic polymorphisms of ARMS2 A69S (rs10490924) and CFH I62V (rs800292). Subfoveal choroidal thickness was also evaluated in a limited number of subjects using the EDI mode of spectral-domain optical coherence tomography.

The prevalence of RPD was significantly higher in RAP eyes than in typical neovascular AMD or in PCV eyes (38.2% of 26 eyes, 13.6% of 132 eyes and 0% of 250 eyes respectively, P < 0.0001). RPD was significantly more prevalent in the elderly (P < 0.0001) and female (P < 0.0001) subjects. The subfoveal choroidal thickness was thinner in eyes with RPD than in those without (129.7 ± 61.7 μm vs 42.6 ± 84.9 μm, P < 0.0001). The frequency of risk variants of ARMS2 A69S was significantly higher in eyes with RPD than in those without RPD (85.7% vs 63.8%, P = 0.0009), although the frequency of CFH I62V was not significantly different between those with and without RPD. Logistic regression analysis revealed that age (odds ratio [OR]:1.10; 95% confidence interval [CI]: 1.04-1.18; p = 0.002), female gender (OR:4.26; 95%CI: 1.72-10.4; p = 0.002), T-allele at ARMS2 A69S (OR: 3.23; 95%CI: 1.36-7.68; p = 0.008) and RAP (OR: 4.25; 95%CI:1.49-12.1; p = 0.007) were risk factors for RPD.

Among eyes with exudative AMD, RPD is more common in eyes with RAP having a thin choroid at the fovea, especially in old, female patients with the risk variant of ARMS2 A69S.