Abstract
Purpose :
It has been well recognized that the myopia rates in urban area are much higher than in rural area. As China’s urbanization process has accelerated, whether the incidence of myopia and the factors influencing myopia progression between urban and rural environments have changed in recent years is not clear. This study aims to investigate the risk factors for myopia, including parental myopia, near work, outdoor activity in urban and rural school-age children of Wenzhou, China.
Methods :
Questionnaire data on environmental factors including time spent in near work, outdoor activities per day, parental refractive status and lighting conditions while reading and writing were collected from 968 second and third grade children of Wenzhou, 668 children in urban schools and 300 children in rural schools, aged from 8 to 10 years old. The refractive status was determined using retinoscopy and subjective refraction. Myopia was defined as spherical equivalent refraction ≤ -0.50 D.
Results :
The prevalence rate of myopia (17.20% in rural children and 20.28% in urban children, p>0.05) and the mean spherical equivalent (-0.11 ± 0.04 D in rural children and -0.19 ± 0.03 D in urban children, p>0.05) showed no significant difference between urban and rural children. Both school children groups spent the same time per day sleeping (9.18 ± 0.08 hours in rural children and 9.15 ± 0.05 hours in urban children, p>0.05). Urban children spent more time in near work after school than rural children (1.76 ± 0.09 hours/d in rural children and 1.99 ± 0.06 hours/d in urban children, p<0.05). Rural children's outdoor activity time (1.93 ± 0.08 hours/d) was significantly higher than in urban children (1.46 ± 0.04 hours/d), p<0.01. There was a significant difference between urban and rural children in the proportion of parents with myopia. In the rural group only 14.66% of the children had one parent with myopia, and 2.33% had two parents with myopia, while the ratio in the urban group was 46.1% and 30.63% respectively, p<0.01. Parental myopia history, including the proportion of high myopia and the initial age of myopia onset, was generally lower in rural parents.
Conclusions :
With China’s modernization process, compared to their parents, the differences of myopia prevalence and environmental factors between urban and rural school-children might have gradually narrowed over time in China.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.