Purpose: To investigate the myopigenic activity change and its risk factors in urban students in Beijing. Methods: 241 primary or secondary students aged 6-17 years from the Beijing Myopia Progression Study (BMPS) were re-examined 3 years after their baseline enrollment. A detailed questionnaire was administered to assess myopigenic activities at both baseline and at the three-year follow-up. 217 students (90.0%) with completed data were included in the analysis. Results: Compared to baseline, primary students (n=123) had significant increases in outdoor sports time (mean ± standard deviation: 3.5 ± 4.3 vs. 2.4 ± 3.0 hours/week, p=0.02), near work time (32.1 ± 13.4 vs. 24.8 ± 9.2 hours/week, p<0.001), diopter hours (128.8 ± 53.3 vs. 97.5 ± 35.9 diopter hours/week, p<0.001), and indoor time (53.8 ± 22.8 vs. 41.4 ± 16.9 hours/week, p<0.001) at the three-year follow-up. At both baseline and follow-up, females spent less time than males on outdoor sports (baseline: 2.4 ± 2.8 vs. 4.0 ± 5.2 hours/week, p=0.006; follow-up: 2.3 ± 3.1 vs. 5.1 ± 5.0 hours/week, p<0.001), and total outdoors (baseline: 11.9 ± 7.9 vs. 14.4 ± 9.5 hours/week, p=0.03; follow-up: 10.5 ± 8.2 vs. 13.9 ± 9.6 hours/week, p=0.005). In the multivariate regression analysis after adjustment by student’s gender, younger students had more increase in both near work time (slope= -0.99 hours/week for age, p=0.009) and indoor time (slope= -2.04 hours/week for age, p=0.001). Conclusions: During the three-year follow-up, primary students had more myopigenic activities. Female students had more myopigenic activities than males at both baseline and follow-up. Children’s age was a significant risk factor for this myopigenic activity change.
Lin , Z., Vasudevan , B., Ciuffreda , K. J., Zhou , H. J., Liang, Y., Mao, G. Y., & Wang , N. L. (2017). Myopigenic activity change and its risk factors in urban students in Beijing: three-year report of Beijing Myopia Progression Study. Ophthalmic Epidemiology. https://doi.org/10.1080/09286586.2017.1307994