Aim: This study evaluated the contributions of various prenatal and postnatal predictive factors to a documented high prevalence of ophthalmological abnormalities in children aged 6.5 years who were born extremely preterm. Methods: We carried out a prospective population-based study of all children born in Sweden at a gestational age of 22 + 0 to 26 + 6 weeks based on the Extremely Preterm Infants in Sweden Study. The main outcome measures were a combined score of visual impairment, refractive errors and strabismus at 6.5 years of age. Models of univariate and multivariable regression were used to analyse potential prenatal and postnatal predictive factors at different clinically relevant time-points from one minute after birth to 30 months. Results: We focused on 399 known extremely preterm survivors and compared them to 300 full-term controls. Significant antecedents for ophthalmological abnormalities included prematurity per se, retinopathy of prematurity that required treatment, severe bronchopulmonary dysplasia and cerebral palsy. Severe intraventricular haemorrhage was no longer a significant risk factor when we adjusted it for the 30-month cognitive and neuromotor development outcomes. Conclusion: This time-course risk analysis model showed a changing panorama of significant risk factors for ophthalmological abnormalities in children aged 6.5 years who were born extremely preterm.
Funding Agencies|Swedish Research Council [2006-3858, 2009-4250]; Jerring Foundation; Stockholm County Council; Karolinska Institute; Sigvard & Marianne Research Foundation for Children Eye Care.; Bernadotte Foundation for Childrens Eye Care Inc.; KMA; Ogonfonden; Swedish Society of Medicine; Nordstromer Foundation; Foundation for Visually Impaired in former Malmohus lan; Stig and Ragna Gorthon Foundation