Family history, near work, outdoor activity, and myopia in Singapore Chinese preschool children

Abstract

Aims To investigate the risk factors for myopia, including near work and outdoor activity, in Singapore Chinese preschool children. Methods A cross-sectional study, with disproportionate random sampling by 6-month age groups, of 3009 Singapore Chinese children aged 6–72 months was performed. Information on family history, near work and outdoor activity was obtained. Spherical equivalent refraction (SEA) was assessed. Results Children with two myopic parents were more likely to be myopic (adjusted OR=1.91; 95% CI 1.38 to 2.63) and to have a more myopic SER (regression coefficient=−0.35; 95% CI −0.47 to −0.22) than children without myopic parents. For each 1 cm taller height, the SER was more myopic by 0.01 dioptres. Neither near work nor outdoor activity was associated with preschool myopia. Conclusions A family history of myopia was the strongest factor associated with preschool myopia. In contrast, neither near work nor outdoor activity was found to be associated with early myopia. These data suggest that genetic factors may play a more substantial role in the development of early-onset myopia than key environmental factors.

Prevalence and associated factors of myopia among primary and middle school-aged students: a school-based study in Guangzhou

“…Similarly, some previous studies among Chinese children also showed that there was no significant association or weak association between outdoor activity and myopia. 7,[37][38][39] The different results may be related to 40,41 Consistent with previous findings showing that parental myopia was significantly related to myopia, and illustrating an increased risk of myopia in children with increasing numbers of myopic parents, 13,17,24,28 the current study demonstrated that there was a trend for higher myopia prevalence among children with a parental myopia history. Both male and female students with one myopic parent or two myopic parents were at a higher risk of myopia than those without myopic parents.…”

Association between parental myopia and the risk of myopia in a child

“…Following this review, a number of manuscripts were excluded due to information, including outcome, the exposure of interest or essential data, being omitted. A total of 16 studies were eligible for final inclusion (12)(13)(14)(15)(16)(17)(26)(27)(28)(29)(30)(31)(32)(33)(34). Of these, six were prospective cohort (12,13,15,17,31,32), eight were cross-sectional (14,16,(26)(27)(28)(29)(30)35) and two were case-control studies (33,34).…”

“…However, there are large inconsistencies in the odds ratios (ORs) among these studies (ranging from 1.48 to 7.90). Furthermore, other studies have identified no statistically significant association between parental myopia and a child's risk of developing myopia (15)(16)(17). These contrasting conclusions may be due to differences in the study designs.…”

“…The present meta-analysis included 16 studies with 8,393 cases of myopia. The selected studies were from four continents (seven from Asia (14,16,26,28,32,34,35), four from Europe (17,29,31,33), three from the United States (12,13,30) and two from Australia (15,27). All of the studies recruited male and female participants aged ≤31 years.…”

“…The majority of studies used questionnaires to ascertain the parents' history of myopia and to assess whether parents wore spectacles or contact lenses at the time of the study. Seven of the studies identified the participants' myopia as a spherical equivalent refraction (SER) ≤-0.5 diopters (D) (14)(15)(16)27,28,33,35) and two studies identified the participants' myopia as a SER ≤-0.75 D (26,32). Three of the studies reported the participants' myopia as a SER ≤-0.75 D in the horizontal and vertical meridians following cycloplegic autorefraction (12,13,30).…”