Abstract
Purpose: :
The aim of this prospective study was to find predictors of abnormal retinal vascularisation in moderately to late preterm newborn infants considered having no risk of developing retinopathy of prematurity (ROP).
Methods: :
Seventy-eight infants (34 girls, 44 boys), 27% born small for gestational age (SGA) were recruited from an ongoing longitudinal study of otherwise healthy premature children born with a gestational age (GA) of 32.0 to 36.9 weeks. Retinal vessel morphology was evaluated manually according to a standardized protocol by one of the authors (AH) during neonatal life (mean postnatal age: 7 days (range 1-28 days). Insulin-like growth factor-I (IGF-I) levels were analyzed in umbilical cord blood.
Results: :
Totally 21/78 infants (27%) had abnormal retinal vessel morphology such as increased vascular tortuosity (n=3), few vascular branching points (n=12), increased number of vascular branching points (n=1), and narrow arterioles and/or venules (n=13). They had significantly lower mean ± SD birth weight (1850 ± 430 versus 2410 ± 450 gram, p<0.0001; -2.0 ± 1.5 versus -0.6 ± 1.1 standard deviation scores (SDS), p=0.0001), birth length (43.2 ± 2.2 versus 45.9 ± 2.5 cm, p<0.0001; -1.6 ± 1.2 versus -0.5 ± 1.4 SDS, p=0.0007), head circumference at birth (30.7 ± 1.6 cm versus 32.1 ± 1.8 cm, p<0.01), with lower GA (33.9 ± 0.9 versus 34.9 ± 1.3, p=0.004) and IGF-I levels (24.6 ± 17.0 versus 46.7 ± 21.5 µg/L, p<0.0001) as well as a higher percentage of SGA infants (57.1% versus 15.8%, p=0.001) and maternal hypertension or preeclampsia (47.6% versus 19.3%, p=0.03). Stepwise logistic regression shows that birth weight is the strongest predictor and no other variables contribute significantly to the model explanation.
Conclusions: :
In this population of moderately to late preterm newborns, birth size, and especially birth weight, seems to affect the vascular system, which could result in a lower threshold for the development of vascular disease later in life.
Keywords: retinal development • clinical (human) or epidemiologic studies: risk factor assessment • pathology: human