Myopia and visual acuity impairment: a comparative study of Greek and Bulgarian school children.
OBJECTIVE
To compare the proportions of school children with myopia and impaired visual acuity in Greece and Bulgaria.


METHODS
A sample of 898 children, aged 10-15 years, was selected from two primary and two secondary schools in a Greek city (Heraklion), and one primary and secondary school in a Bulgarian city (Stara Zagora). Five hundred and eighty eight children were Greek (65.5%, mean age 12.5 +/- 0.08 years) and 310 Bulgarian (34.5%, age 12.4 +/- 0.07 years). VA was assessed with the habitual refractive correction. Refractive error was measured in the absence of cycloplegia using an auto-refractor.


RESULTS
The percentage of children, tested with their habitual refractive correction, with decimal VA <0.5 in at least one eye was 11.7% (95% CI 9.1-14.3%) for Greek and 5.2% (95% CI 2.7-7.6%) for Bulgarian pupils. The percentage of myopic children also differed between the two countries with the proportion with myopic refractive error <or=-0.75 D and decimal VA <0.8 at primary school level being 14.1% and 28.9% in Stara Zagora and Heraklion respectively and 13.0% and 46.9% (95% CI 18.2-29.2%, p < 0.0001) at secondary school level. Among the myopic pupils only 35.8% used corrective spectacles in Stara Zagora, compared to 70.7% of the children in Heraklion. Finally, myopia appeared more prevalent in female adolescents with the effect being statistically significant only for Greek children (55% vs 40% of males, p = 0.015).


CONCLUSIONS
The increased proportion of myopic children in Heraklion, compared to Stara Zagora, may arise from a number of environmental and socio-economic factors, which need to be further investigated in order to understand the differences observed among European populations.
Institute of Vision and Optics (IVO), School of Health Sciences, University of Crete, PO Box 2208, 71003 Heraklion, Crete. plainis@med.uoc.gr
Sotiris
S
Plainis
Joanna
J
Moschandreas
Panagoula
P
Nikolitsa
Eleani
E
Plevridi
Trisevgeni
T
Giannakopoulou
Vania
V
Vitanova
Paraskevi
P
Tzatzala
Ioannis G
IG
Pallikaris
Miltiadis K
MK
Tsilimbaris
D000293:Adolescent; D000367:Age Factors; D001251:Astigmatism / Q000453:epidemiology / Q000503:physiopathology*; D002031:Bulgaria / Q000453:epidemiology; D002648:Child; D005260:Female; D006115:Greece / Q000453:epidemiology; D006801:Humans; D008297:Male; D009216:Myopia / Q000453:epidemiology / Q000503:physiopathology*; D013223:Statistics as Topic; D014786:Vision Disorders / Q000453:epidemiology / Q000503:physiopathology*; D014792:Visual Acuity / Q000502:physiology*