Genetic influence on choroidal vascularity index: the healthy twin study

Abstract This study aimed to investigate the heritability of genetic influence on macular choroidal vascularity index (CVI). This was a cross-sectional healthy twin study. We included 373 Korean adults with healthy eyes from 79 families. CVI, Total choroidal area (TCA) and luminal area (LA) were measured using horizontal scan of spectral-domain optical coherence tomography with enhanced depth imaging. Characteristics of the participants were investigated (age, gender, drinking habits, smoking status, axial length, hypertension, and diabetes). The correlations of these characteristics with CVI were assessed using univariate and subsequently multivariate regression models. Participants who were older and had a higher intraocular pressure, higher diastolic blood pressure, and lower pulse pressure showed associations with lower CVI (p < 0.001, p = 0.014, p = 0.005, and p = 0.015, respectively). The covariate-adjusted heritability (±standard error) of the CVI was 0.716 ± 0.091, and the heritabilities of the TCA and LA were 0.691 ± 0.089 and 0.634 ± 0.100, respectively. The CVI, TCA, and LA are highly heritable.