Associations between Environmental Tobacco Smoke Exposure in Early Life and Astigmatism among Chinese Preschool Children

Abstract

This study aimed to investigate the association between environmental exposure to tobacco smoke (ETS) during early life and astigmatism in Chinese preschool children. In this cross-sectional study, information concerning prenatal and postnatal ETS exposure at three stages of early life (during pregnancy, from birth to one year and from one to three years), visual problems of children and parents (including a confirmed diagnosis of astigmatism), socio-demographics and perinatal characteristics were obtained from 27,890 parent-reported questionnaires. Logistic regression analyses were undertaken to yield adjusted odds ratios (OR) for assessing their associations. After adjusting for the potential confounders, children were more likely to exhibit astigmatism when they were exposed to ETS during pregnancy + from one to three years [OR (95% CI) = 1.37 (1.02, 1.84)], or from birth to one year + from one to three years [OR (95% CI) = 1.36 (1.11, 1.66)], or during pregnancy + from birth to one year + from one to three years old [OR (95% CI) = 1.29 (1.16, 1.45)], compared to children without ETS exposure at any stage of early life. In Chinese preschool children, prenatal and postnatal astigmatism was associated with ETS exposure; the greater the ETS dose, the greater the astigmatism risk.

Screen Exposure during Early Life and the Increased Risk of Astigmatism among Preschool Children: Findings from Longhua Child Cohort Study

“…The astigmatism cases were identified as positive in a large sample screening and further diagnosed as astigmatism at the ophthalmic clinic, and reported by parents or other caregivers, which might lead to information bias. The findings from our published study [21], which used the same measurement of astigmatism, were consistent with the findings from the multi-ethnic pediatric eye disease and Baltimore pediatric eye disease studies [23] which used cycloplegic refraction to define astigmatism, thus illustrating that to some extent, our measurements were reliable. Additionally, the measurement of outcome was monotonous and not graded.…”

“…In the present study, therefore, the following questions [21] were asked about the child's eye conditions: (1) Has your child ever been diagnosed as having poor sight by the oculist? (0 = 'no', 1 = 'yes', 2 = 'uncertain'); and if yes, the subsequent questions were asked separately, i.e., questions (2)-(7): Has your child ever been diagnosed as having astigmatism/myopia/hyperopia/strabismus/amblyopia/other common visual problems?…”

Combination Effect of Outdoor Activity and Screen Exposure on Risk of Preschool Myopia: Findings From Longhua Child Cohort Study

“…As shown in the previous studies (26)(27)(28), the vision screening for preschool children is performed by ophthalmologists from Longhua District Maternal and Child Health Hospital twice per school year, since 2017. The results of the vision screening are conveyed to children's caregivers by teachers.…”

“…The ophthalmologists from Longhua District Maternal and Child Health Hospital defined the children's refractive problem as myopia if the spherical equivalent was equal to or worse than −0.50 D in at least one eye (27). In the present study, therefore, primary caregivers completed the survey questions about whether the child had been diagnosed with any types of refractive error based on the written report of the vision screening visit (26)(27)(28). The final analysis included only myopic and emmetropic children.…”

Associations Between Screen Exposure in Early Life and Myopia amongst Chinese Preschoolers

“…Questions with regard to child's eye conditions were listed as following [19]: (1) Has your child ever been diagnosed as having poor sight by the oculist? (0 = 'no', 1 = 'yes', 2 = 'uncertain');…”