Association between sleep-wake schedules and myopia among Chinese school-aged children and adolescents: a cross-sectional study.

Background: This study aimed to investigate the relationship between sleep-wake schedules and self-reported myopia in the pediatric population.

Methods: In this cross-sectional study in 2019, school-aged children and adolescents in the Baoan District of Shenzhen City were sampled using a stratified cluster sampling approach. Sleep-wake schedules of children were determined by a self-administered questionnaire. The age that participants first reported using myopia correction glasses or contact lenses was used to identify those with myopia. Pearson χ test was used to examine differences in myopia prevalence among participants with different characteristics. Multivariate logistic regression, adjusted for potential confounding variables, was applied to examine the relationship between sleep-wake schedule and risk of self-reported myopia, and a stratification analysis by school grade was also performed.

Results: A total of 30,188 students were recruited. In this study, the overall prevalence of myopia was 49.8%, with prevalence rates of 25.6%, 62.4%, and 75.7% for primary, junior high, and senior high school students, respectively. Students with irregular sleep-wake times reported a higher prevalence of myopia than those with regular sleep-wake times. Nighttime sleep duration of < 7 hours/day (h/d) (OR = 1.27, 95%CI: 1.17-1.38), no daytime nap (OR = 1.10, 95%CI: 1.03-1.18), irregular weekday bedtime (OR = 1.11, 95%CI: 1.05-1.17), irregular weekday wake time (OR = 1.21, 95%CI: 1.12-1.30), weekend bedtime delayed > = 1 h/d (OR = 1.20, 95%CI: 1.11-1.29, P < 0.001), weekend wake time delayed > = 1 h/d (OR = 1.11, 95%CI: 1.03-1.19), irregular sleep-wake time on weekdays (OR = 1.13, 95%CI: 1.07-1.19), and social jetlag > = 1 h (OR = 1.08, 95%CI: 1.03-1.14) were likely to be associated with increased risks of self-reported myopia after adjusting age, sex, grade, parental education level, family income, parental myopia, academic record, and academic workload. When stratified by school grade, we observed that nighttime sleep duration < 7 h/d, no daytime naps, and irregular sleep-wake time on weekdays were significantly associated with self-reported myopia in primary school students.

Conclusion: Insufficient sleep and irregular sleep-wake schedules can increase the risk of self-reported myopia in children and adolescents.