title: Relative Contribution of Risk Factors for Early-Onset Myopia in Young Asian Children.
abstract: OBJECTIVE
  To investigate the associations of near work, outdoor activity, and anthropometric risk factors with early-onset myopia in Singaporean preschool children.
  
  
  METHODS
  Pregnant women who attended their first-trimester clinic at two major maternity units were recruited for the GUSTO birth cohort (n = 1236). Cycloplegic autorefraction and axial length (AL) were obtained in 3-year-old children (n = 572). Parents completed detailed questionnaires on parental myopia, near work, and outdoor activities when the child was 2 years of age. Height and weight were measured in the children at various time points from birth to 3 years of age.
  
  
  RESULTS
  Among the cohort of 572 children, 35 children (6.1%) had early-onset myopia. In multivariable regression models, compared to children whose parents were not myopic, those with two myopic parents were more likely to have a more myopic spherical equivalent (SE) (regression coefficient: -0.36; 95% confidence interval [CI]: -0.61 to -0.11) and longer AL (regression coefficient: 0.24; 95% CI: 0.10-0.39) and more likely to have myopia (odds ratio [OR] = 4.8; 95% CI: 1.4-16.6). Neither near work nor outdoor activity was associated with SE, AL, and myopia. Taller children were found to have longer AL at birth and at 12, 24, and 36 months, but there were no associations with SE.
  
  
  CONCLUSIONS
  Genetic factors may have a greater contribution to early development of refractive error compared to environmental factors.
authors.affiliation: Saw Swee Hock School of Public Health National University of Singapore, Singapore.
authors.forename: Sharon Yu Lin
authors.initials: SY
authors.lastname: Chua
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 3School of Public Health, DUKE-NUS Medical School, Singapore.
authors.forename: M Kamran
authors.initials: MK
authors.lastname: Ikram
authors.affiliation: Saw Swee Hock School of Public Health National University of Singapore, Singapore.
authors.forename: Chuen Seng
authors.initials: CS
authors.lastname: Tan
authors.affiliation: Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 5Division of Paediatric Endocrinology and Diabetes, Khoo Teck Puat-National University Children's Medical Institute, National University Hospital, Nati.
authors.forename: Yung Seng
authors.initials: YS
authors.lastname: Lee
authors.affiliation: School of Public Health, Boston University, Boston, Massachusetts, United States.
authors.forename: Yu
authors.initials: Y
authors.lastname: Ni
authors.affiliation: Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore.
authors.forename: Cai
authors.initials: C
authors.lastname: Shirong
authors.affiliation: Singapore Institute for Clinical Sciences, Agency for Science and Technology (A*STAR), Singapore 9Liggins Institute, University of Auckland, Auckland, New Zealand.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Gluckman
authors.affiliation: Singapore Institute for Clinical Sciences, Agency for Science and Technology (A*STAR), Singapore 8Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore.
authors.forename: Yap-Seng
authors.initials: YS
authors.lastname: Chong
authors.affiliation: Department of Paediatric Endocrinology, KK Women's and Children's Hospital, Singapore.
authors.forename: Fabian
authors.initials: F
authors.lastname: Yap
authors.affiliation: Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 3School of Public Health, DUKE-NUS Medical School, Singapore 11Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Tien-Yin
authors.initials: TY
authors.lastname: Wong
authors.affiliation: Department of Ophthalmology, National University Hospital, Singapore.
authors.forename: Cheryl S
authors.initials: CS
authors.lastname: Ngo
authors.affiliation: Saw Swee Hock School of Public Health National University of Singapore, Singapore 2Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 3School of Public Health, DUKE-NUS Medical School, Singapore.
authors.forename: Seang-Mei
authors.initials: SM
authors.lastname: Saw
mesh_terms: D000328:Adult; D000886:Anthropometry; D044466:Asian People; D002675:Child, Preschool; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007223:Infant; D007899:Leisure Activities; D008297:Male; D015999:Multivariate Analysis; D009216:Myopia / Q000209:etiology* / Q000235:genetics; D016017:Odds Ratio; D010290:Parents; D011932:Reading; D012307:Risk Factors; D011795:Surveys and Questionnaires