A cohort study of incident myopia in Singaporean children.
OBJECTIVE
To determine the risk factors of incident myopia in a school-based cohort study in Singaporean children.


METHODS
A 3-year prospective cohort study was conducted in Singaporean school children aged 7 to 9 years in three schools at entry. Chinese children without myopia at baseline (n = 994) were included in the analysis. The main outcome was incident myopia, defined as spherical equivalent (SE) at least -0.75 D based on cycloplegic autorefraction. Other definitions of incident myopia, at least -0.5 D and at least -1.0 D, were also assessed.


RESULTS
After controlling for school, age, gender, income, reading in books per week and intelligence quotient (IQ) test scores, we found the relative risk (RR) of incident myopia defined as -0.75 D to be 1.55 (95% confidence interval [CI] 1.18-2.04) for two versus no myopic parents. The multivariate RR of myopia for IQ in the third versus first tertile was 1.50 (95% CI, 1.19-1.89). However, the RR of incident myopia was 1.01 (95% CI, 0.97-1.05) for every unit increase in books read per week. Similar results were obtained with definitions of -0.5 and -1.0 D for incident myopia.


CONCLUSIONS
These data provide new prospective evidence of essential links between parental myopia, IQ scores and subsequent myopia development. However, reading in books per week was not associated with incident myopia.
Saw
Seang-Mei
SM
Department of Community, Occupational, and Family Medicine, National University of Singapore, Singapore. cofsawsm@nus.edu.sg
Shankar
Anoop
A
Tan
Say-Beng
SB
Taylor
Hugh
H
Tan
Donald T H
DT
Stone
Richard A
RA
Wong
Tien-Yin
TY
D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007361:Intelligence Tests; D008297:Male; D009216:Myopia / Q000453:epidemiology*; D012306:Risk; D012307:Risk Factors; D012846:Singapore / Q000453:epidemiology; D011795:Surveys and Questionnaires