Beta-peripapillary atrophy of the optic disc and its determinants in Japanese eyes: a population-based study

To assess β-zone of peripapillary atrophy (β-PPA) and its relationship between systemic and ocular factors, especially glaucoma, in a Japanese population.

Fundus photographs obtained from 2129 normal, 84 primary open-angle glaucoma (POAG) and 10 primary angle closure glaucoma subjects from 3021 participants aged 40 years or older in the Tajimi Study were analysed planimetrically. If both eyes of a subject met inclusion criteria, one eye was randomly chosen.

The presence rates of β-PPA were 54.7 and 77.4% (p < 0.001) and β-PPA area averaged 0.67 and 1.06 mm² (p < 0.001), in normal and POAG eyes, respectively. Myopia was closely related to disc ovality and β-PPA. In normal eyes, logistic analysis showed that the presence of β-PPA was correlated with older age, female gender, myopic refraction, thicker central corneal thickness (CCT), greater disc ovality and disc centre to fovea (disc-fovea) distance and lower intraocular pressure (IOP) (p = 0.039 ~ <0.001); and multiple regression analysis showed that β-PPA area was correlated with older age, myopic refraction, greater disc area and ovality, disc-fovea distance and lower IOP (p = 0.004 ~ <0.001) after adjusting other factors.

The presence and size of β-PPA in normal eyes were correlated with older age, greater disc ovality and disc-fovea distance and lower IOP. Further, its presence was associated with female gender, thicker CCT and its size with greater disc area. β-zone of peripapillary atrophy (β-PPA) was also associated with POAG. These results provide reference data of the β-PPA in a Japanese population and possibly indicate clinical importance of β-PPA in glaucoma clinic.