Incidence and risk factors of retinopathy of prematurity in a tertiary eye hospital in Tehran.
OBJECTIVE
To determine the incidence and risk factors of retinopathy of prematurity (ROP) in premature infants referred to a tertiary eye hospital during 2003-7 to provide preliminary evidence about ROP in Iran.


METHODS
In a cross-sectional study, data for premature infants screened for ROP in Farabi Eye Hospital including possible risk factors and eye exams' results were recorded and analysed using chi(2), univariate and multiple regressions. Severe ROP was defined as ROP needing treatment or stage 4 or 5 of ROP.


RESULTS
Among 953 premature infants, there were 329 (34.5%) different stages of ROP. Severe ROP was seen in 22.6% (215/953) of infants (16.5%: treatable, 6.1%: advanced untreatable). The mean gestational age (GA) and birth weight (BW) of infants with severe ROP were 28.8 (SD 2.4) weeks and 1256 (389) g respectively. Univariate analysis showed a significant relation between GA, BW, oxygen therapy, blood transfusion and ROP (p<0.001), while multiple-regression methods showed GA, BW and oxygen therapy as independent predictors of ROP (p<0.001, 0.019 and 0.033, respectively).


CONCLUSIONS
The authors observed a relatively high incidence of ROP in this series, especially its severe form affecting relatively more mature infants, which merits further investigation. GA, BW and oxygen therapy were independent ROP determinants.
Karkhaneh
R
R
Eye Research Centre, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran. karkhane@sina.tums.ac.ir
Mousavi
S Z
SZ
Riazi-Esfahani
M
M
Ebrahimzadeh
S A
SA
Roohipoor
R
R
Kadivar
M
M
Ghalichi
L
L
Mohammadi
S F
SF
Mansouri
M R
MR
D000704:Analysis of Variance; D001766:Blindness / Q000517:prevention & control; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007234:Infant, Premature; D007492:Iran / Q000453:epidemiology; D008297:Male; D008403:Mass Screening; D009887:Ophthalmoscopy / Q000379:methods; D010102:Oxygen Inhalation Therapy / Q000009:adverse effects; D012178:Retinopathy of Prematurity / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D065227:Transfusion Reaction