Ophthalmologic Outcome of Extremely Preterm Infants at 6.5 Years of Age: Extremely Preterm Infants in Sweden Study (EXPRESS).

IMPORTANCE: This follow-up study of extremely preterm (EPT) children (<27 weeks' gestational age [GA] at birth) revealed major eye and visual problems in 37.9% (147 of 388) of all EPT infants and in 55.4% (67 of 121) of the most immature subgroups at 6.5 years of age. These major eye and visual problems were strongly associated with treatment-requiring retinopathy of prematurity (ROP). OBJECTIVES: To investigate the ophthalmologic outcome of a national cohort of EPT children at 6.5 years of age and to evaluate the impact of prematurity and ROP. DESIGN, SETTING, AND PARTICIPANTS: All surviving EPT children born in Sweden between April 1, 2004, and March 31, 2007, were included and compared with a matched term control group, as part of a prospective national follow-up study. MAIN OUTCOMES AND MEASURES: Visual acuity, refraction in cycloplegia, and manifest strabismus were evaluated and compared with GA at birth and with treatment-requiring ROP. RESULTS: The study cohort comprised 486 participants. The mean (SD) GA of the children who were included was 25 (1) weeks, and 45.7% (222 of 486) were female. At a median age of 6.6 years, 89.3% (434 of 486) of eligible EPT children were assessed and compared with 300 control group children. In the EPT group, 2.1% (9 of 434) were blind, 4.8% (21 of 434) were visually impaired according to the World Health Organization criteria, and 8.8% (38 of 434) were visually impaired according to the study criteria. Strabismus was found in 17.4% (68 of 390) and refractive errors in 29.7% (115 of 387) of the EPT children compared with 0% (0 of 299) and 5.9% (17 of 289), respectively, of the control children (P < .001). Altogether at 6.5 years of age, 37.9% (147 of 388) of the EPT children had some ophthalmologic abnormality compared with 6.2% (18 of 290) of the matched control group (95% CI of the difference, 26.1%-37.2%). When treatment-requiring ROP was adjusted for, no significant association between GA and visual impairment could be detected. For refractive errors, the association with GA remained after adjustment for treatment-requiring ROP (odds ratio, 0.72; 95% CI, 0.58-0.91 for each 1-week increment). CONCLUSIONS AND RELEVANCE: In a Swedish national cohort of EPT children at 6.5 years of age, major eye and visual problems were frequently found. Treatment-requiring ROP was a stronger impact factor than GA on visual impairment and strabismus, but not on refractive errors, as a whole. In modern neonatal intensive care settings, ophthalmologic problems continue to account for a high proportion of long-term sequelae of prematurity.

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.

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.

Swedish national register for retinopathy of prematurity (SWEDROP) and the evaluation of screening in Sweden.

OBJECTIVES: To evaluate screening for retinopathy of prematurity (ROP) in Sweden and to investigate possible modifications of the present screening guidelines. METHODS: Infants in Sweden with a gestational age (GA) of 31 weeks + 6 days or less are screened for ROP. Data from the Swedish national register for ROP (SWEDROP) during 2008 and 2009 were extracted and compared with a national perinatal quality register. RESULTS: In SWEDROP, there were 1791 infants born before a GA of 32 weeks from January 1, 2008, through December 31, 2009. Another 70 infants were registered in the perinatal quality register but not in SWEDROP (dropout rate, 3.8% [70 of 1861 infants]). Seven infants died before termination of screening. In the final study cohort (1784 infants), 15.6% had mild ROP and 8.5% had severe ROP. Treatment was performed in 4.4% of the infants, none of whom had a GA at birth of more than 28 weeks. Nine infants with a GA of more than 28 weeks at birth developed stage 3 ROP, which regressed spontaneously. The total number of examinations was 9286 (964 in infants with a GA of 31 weeks), and the mean (range) number of examinations of each infant was 5.2 (1-30). CONCLUSIONS: The SWEDROP, a quality register for ROP, has a national coverage (ie, participation) of 96%. Data from 2008 to 2009 show that it seems possible to reduce the upper limit for screening in Sweden by 1 week, including only infants with a GA of 30 weeks + 6 days or less. However, such a change should be combined with a strong recommendation to neonatologists to refer also severely ill and more "mature" infants.

Screening for retinopathy of prematurity in infants born before 27 weeks' gestation in Sweden.

OBJECTIVE: To analyze screening for retinopathy of prematurity (ROP) during a 3-year period in a national cohort of infants born before 27 weeks' gestation. METHODS: A national prospective study of neonatal morbidity in extremely preterm infants was performed in Sweden between April 1, 2004, and March 31, 2007. Screening for ROP was to start in the fifth postnatal week and to continue weekly until complete vascularization of the retina or until regression of ROP. RESULTS: The first eye examination was performed no later than the sixth postnatal week in 84.8% of 506 infants, and the last examination was performed at postmenstrual age (PMA) of 38 weeks or later in 96.2% of infants. The mean and median numbers of days between examinations in the total cohort were 8.6 and 7.9 days, respectively (range, 1-27.8 days), and the mean and median numbers of examinations were 12 and 10, respectively. Most infants were treated during a limited period (eg, at PMA of 39 weeks, 75.0% of infants had been treated). CONCLUSIONS: The objective of screening for ROP is timely detection of ROP before reaching treatment of criteria, ie, type 1 ROP, according to the Early Treatment for ROP recommendations. In our population of infants born before 27 weeks' gestation, the first examination could safely be postponed until PMA of 31 weeks because the onset of ROP stage 3 did not occur before then and criteria for treatment were not reached before PMA of 32 weeks. Gestational age at birth and PMA at the time of examination should be considered when deciding when and where the next examination should be performed.

Incidence of retinopathy of prematurity in infants born before 27 weeks' gestation in Sweden.

OBJECTIVE: To determine the incidence of retinopathy of prematurity (ROP) in extremely preterm infants born before 27 weeks' gestation in Sweden during a 3-year period. METHODS: A national, prospective, population-based study was performed in Sweden from April 1, 2004, to March 31, 2007. The ophthalmologic part of the study was separately organized, and screening for ROP was performed beginning postnatal week 5. The criteria for the treatment of ROP agreed with the recommendations of the Early Treatment for Retinopathy of Prematurity Cooperative Group. RESULTS: During the study, 506 of 707 live-born infants survived until the first eye examination. Of these, 368 (72.7%) had ROP: 37.9% had mild ROP and 34.8% had severe ROP. Ninety-nine infants (19.6%) were treated. Gestational age at birth was a stronger predictor of ROP than was birth weight. A log-linear relationship between severe ROP and gestational age at birth was found in the present cohort, and the risk of ROP was reduced by 50% for each week of increase in gestational age at birth. CONCLUSIONS: Today, extremely preterm infants are surviving, and this population-based study with ROP as a primary outcome shows a higher incidence of this condition than in previously reported national cohorts.