Refractive error, ocular and general parameters and ophthalmic diseases. The Beijing Eye Study

To assess relationships between refractive error and ocular and general parameters.

The Beijing Eye Study is a population-based study which included 4,439 Chinese subjects examined in 2001, with a follow-up examination in 2006, in which 3,251 (73.2%) subjects participated.

In multivariate regression analysis, increasing (hyperopic) refractive error was significantly associated with the systemic parameters of higher age (P < 0.001), rural region (P < 0.001), lower education level (P = 0.004), higher frequency of ever smoking (P = 0.02), and higher body mass index (P = 0.02). Adjusted for the systemic parameters, increasing (hyperopic) refractive error was significantly associated with higher best-corrected visual acuity (P < 0.001), lower anterior chamber depth (P < 0.001) and narrower chamber angle (P < 0.001), lower intraocular pressure (P = 0.001), lower amount of nuclear cataract (P = 0.007), smaller beta zone of parapapillary atrophy (P < 0.001), a lower prevalence of open-angle glaucoma (P = 0.01), and a higher prevalence of age-related macular degeneration (P = 0.04). Refractive error was not significantly (P > 0.05) associated with the prevalence of trachoma, non-glaucomatous optic nerve damage, and retinal vein occlusions, nor with mortality.

In the adult Chinese population, hyperopic subjects compared with myopic subjects were older, lived predominately in the rural regions, had a lower level of education, smoked more, and were more obese. In addition, the hyperopic subjects had a lower intraocular pressure, a higher best-corrected visual acuity, a shallower anterior chamber depth and narrower anterior chamber angle, lower amount of nuclear cataract, smaller beta zone of parapapillary atrophy, a lower prevalence of open-angle glaucoma, and a higher prevalence of age-related macular degeneration.