Ophthalmologic outcome at 30 months' corrected age of a prospective Swedish cohort of children born before 27 weeks of gestation: the extremely preterm infants in sweden study

Abstract

Importance: Follow-up at 30 months' corrected age reveals eye and visual problems in one-third of children born extremely prematurely (<27 weeks' gestation).

Objective: To investigate the ophthalmologic outcome of extremely preterm children at 30 months' corrected age. DESIGN, SETTING, AND PARTICIPANTS A prospective, population-based follow-up study (Extremely Preterm Infants in Sweden Study [EXPRESS]) was conducted in Sweden. The population included extremely preterm infants (<27 weeks' gestation) born in Sweden between 2004 and 2007, of whom 491 survived until age 2.5 years. Screening for retinopathy of prematurity (ROP) was performed in the neonatal period. At 30 months' corrected age, an ophthalmologic assessment was performed in 411 of 491 children (83.7%).

Main outcomes and measures: Visual acuity, manifest strabismus, and refractive errors were evaluated.

Results: Visual impairment was identified in 3.1% of the children, and 1.0% were blind. Refractive errors, defined as myopia less than -3 diopters (D), hypermetropia greater than +3 D, astigmatism 2 D or more, and/or anisometropia 2 D or more, were found in 25.6% of the children, and 14.1% had manifest strabismus. There were significant associations between visual impairment and treated ROP (P = .02), cognitive disability (P < .001), and birth weight (P = .02). Multiple regression analyses revealed significant associations between strabismus and treated ROP (P < .001), cognitive disability (P < .01), and cerebral palsy (P = .02). Refractive errors were significantly correlated with severity of ROP (right eye, P < .001; left eye, P < .01). Children who had been treated for ROP had the highest frequency (69.0%) of eye and visual abnormalities.

Conclusions and relevance: One-third of the extremely prematurely born children in this study had some kind of eye or visual problems, such as visual impairment, strabismus, or major refractive error. Despite being born extremely preterm, the present cohort has a similar prevalence of blindness and visual impairment as in previous Swedish cohorts of children born less prematurely.