Sleep Duration, Sleep Habits, and Social Jetlag From 4 to 6 years Their Impacts on Myopia Among School-Aged Children: The Ma'anshan Birth Cohort Study.

Purpose: To examine the associations of sleep parameters and their trajectories at preschool age with myopia among school-aged children by using a birth cohort study design.

Patients and methods: All participants were recruited from the Ma'anshan Birth Cohort Study. Sleep duration, sleep habits, and social jetlag were collected in 4 years, 5.5 years, and 6 years. Cycloplegic refraction and ocular biometry were performed at 7 years. Key statistical analyses were performed using the latent class growth models, binary logistic regression, generalized linear models, and linear mixed models, respectively.

Results: A total of 1561 children were included in the study (mean age of 7.93 years, 52.6% boys). Social jetlag of at least 1 hour at age 4 was positively linked to an increased risk of myopia in school-age children and axial length (AL) but negatively correlated with spherical equivalent refraction (SER) (P<0.05). Inadequate sleep duration at 5.5 years was associated with an increase in AL among school-age children (β=0.16; 95% CI: 0.07-0.24). A pattern of increasing-declining social jetlag was positively correlated with AL/CR ratio (RR=1.55; 95%CI: 1.01-2.37). Poor sleep habits, higher social jetlag at age 4, and the declining-increasing trajectory of social jetlag were negatively associated with SER in school-aged children (P<0.05). Furthermore, the declining-increasing and increasing-declining trajectories of social jetlag were positively correlated with the elongation of AL.

Conclusion: The correlations between sleep parameters at preschool age and myopia in school-aged children reveal that maintaining regular sleep habits in preschool may contribute to the early prevention of myopia.