Associated factors for age related maculopathy in the adult population in China: the Beijing eye study

BACKGROUND: To evaluate factors associated with the prevalence of age related maculopathy (ARM) in the adult Chinese population. METHODS: The Beijing Eye Study, a population based prevalence study, included 4439 out of 5324 subjects from a rural area and an urban region of greater Beijing, aged 40+ years and invited to participate (response rate 83.4%). Fundus photographs were graded using the Wisconsin Age-Related Maculopathy Grading system. The following parameters were graded: drusen size, drusen type, and the area covered by drusen; pigmentary abnormalities; geographic atrophy; and exudative ARM. RESULTS: Fundus photographs were available for 8655 eyes of 4376 (98.6%) subjects. Early age related macular degeneration (ARD), late ARD, and exudative ARD, respectively, were present in 1.4%, 0.20%, and 0.10% of the subjects. In a binary logistic regression analysis, early ARM was statistically associated with age (p<0.001; 95% CI: 1.04 to 1.08), hyperopic refractive error (p = 0.008; 95% CI: 1.04 to 1.28), rural region (p<0.001; 95% CI: 0.17 to 0.49), and lower level of education (p = 0.01; 95% CI: 1.07 to 1.65). Early ARM was not significantly associated with the optic disc size (p = 0.42), and size of beta zone of peripapillary atrophy (p = 0.28), the self reported diagnosis of diabetes mellitus (p = 0.39; OR: 1.37; 95% CI: 0.66 to 2.85), amount of cortical cataract (p = 0.72), subcapsular cataract (p = 0.98), nuclear cataract (p = 0.26), sex (p = 0.23), cataract surgery (p = 1.0; OR: 0.96; 95% CI: 0.13 to 6.95), glaucomatous optic nerve damage (p = 0.77; OR: 0.62; 95% CI: 0.15 to 2.52), and history of smoking (p = 0.66; OR: 1.14; 95% CI: 0.65 to 2.00). CONCLUSIONS: Hyperopic refractive error besides age was the single most important risk factor for ARM in adult Chinese. Other associated factors were rural region and lower level of education.