Retinopathy of prematurity and brain damage in the very preterm newborn

Retinopathy of prematurity and neurodevelopmental outcome and quality of life at 10 years of age

Objective

In a cohort of 10-year-old children born extremely preterm, we evaluated the hypothesis that increasing severity of retinopathy of prematurity (ROP) is associated with increasing frequency of unfavorable neurodevelopmental and quality of life outcomes.

Study Design

Study participants were classified according to the severity of ROP. At 10 years of age, their neurocognitive abilities, academic achievement, and gross motor function were assessed, and they were evaluated for autism spectrum disorder, anxiety, depression, and quality of life.

Results

After adjustment for sample attrition and confounders, only the association with lower quality of life persisted. Increasing severity of visual impairment was associated with worse neurodevelopmental outcomes and lower quality of life.

Conclusion

Among extremely preterm children, severity of visual impairment, but not severity of ROP, was associated with adverse neurodevelopmental outcomes at 10 years of age. Both severe ROP and more severe visual impairment were associated with lower quality of life.

Relationships between retinopathy of prematurity without ophthalmologic intervention and neurodevelopment and vision at 2 years

BACKGROUND

Severe retinopathy of prematurity (ROP) is associated with adverse outcomes. Relationships between milder ROP and outcomes have not been defined. We hypothesized that children with ROP stage ≤3 who did not receive ophthalmologic intervention would have worse motor, cognitive, and language skills and more vision abnormalities than children without ROP.

METHODS

This was a secondary analysis of a randomized trial evaluating the effects of myo-inositol on ROP in the NICHD Neonatal Research Network. Primary outcomes were Bayley Scales of Infant Development composite scores; secondary outcomes included behavioral difficulties and ophthalmologic measures. Outcomes were compared using adjusted linear or modified Poisson models.

RESULTS

Of 506 children, 173 (34%) had no ROP, 262 (52%) had ROP stage ≤3 without intervention, and 71 (14%) had ROP with intervention. There was no difference in motor, cognitive, or language scores between children with ROP stage ≤3 without intervention and children without ROP. Children with ROP stage ≤3 without intervention had a higher rate of strabismus compared to children without ROP (p = 0.040).

CONCLUSION

Children with ROP stage ≤3 without intervention did not have adverse neurodevelopmental outcomes at 2 years' corrected age compared to children without ROP but did have an increased incidence of strabismus.

IMPACT

This study addresses a gap in the literature regarding the relationship between milder forms of retinopathy of prematurity (ROP) that regress without intervention and neurodevelopment and vision outcomes. Children with a history of ROP stage ≤3 without intervention have similar neurodevelopmental outcomes at 2 years' corrected age as children born extremely preterm without a history of ROP and better outcomes than children with a history of ROP with ophthalmologic intervention. Counseling about likely neurodevelopment and vision outcomes for children born extremely preterm with a history of ROP may be tailored based on the severity of ROP.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov ID: Inositol to Reduce Retinopathy of Prematurity Trial: NCT01954082.

Retinopathy of prematurity and neurodevelopmental outcomes in preterm infants: A systematic review and meta-analysis

Background

Retinopathy of prematurity (ROP) and abnormal brain development share similar risk factors and mechanisms. There has been contrasting evidence on the association of ROP with adverse neurodevelopmental outcomes.

Objective

We analysed the association between ROP at levels of severity and treatment with all neurodevelopmental outcomes until adolescence.

Data source

We followed PRISMA guidelines and searched Medline and Embase between 1 August 1990 and 31 March 2022.

Study selection and participants

Randomised or quasi-randomised clinical trials and observational studies on preterm infants (<37 weeks) with ROP [type 1 or severe ROP, type 2 or milder ROP, laser or anti-vascular endothelial growth factor (VEGF) treated] were included.

Data extraction and synthesis

We included studies on ROP and any neurocognitive or neuropsychiatric outcomes.

Outcomes

The primary outcomes were as follows: cognitive composite scores evaluated between the ages of 18 and 48 months by the Bayley Scales of Infant and Toddler Development (BSID) or equivalent; neurodevelopmental impairment (NDI; moderate to severe NDI or severe NDI), cerebral palsy, cognitive impairment; and neuropsychiatric or behavioural problems. The secondary outcomes were as follows: motor and language composite scores evaluated between the ages of 18 and 48 months by BSID or equivalent; motor/language impairment; and moderate/severe NDI as defined by the authors.

Results

In preterm infants, "any ROP" was associated with an increased risk of cognitive impairment or intellectual disability [n = 83,506; odds ratio (OR): 2.56; 95% CI: 1.40-4.69; p = 0.002], cerebral palsy (n = 3,706; OR: 2.26; 95% CI: 1.72-2.96; p < 0.001), behavioural problems (n = 81,439; OR: 2.45; 95% CI: 1.03-5.83; p = 0.04), or NDI as defined by authors (n = 1,930; OR: 3.83; 95% CI: 1.61-9.12; p = 0.002). Type 1 or severe ROP increased the risk of cerebral palsy (OR: 2.19; 95% CI: 1.23-3.88; p = 0.07), cognitive impairment or intellectual disability (n = 5,167; OR: 3.56; 95% CI: 2.6-4.86; p < 0.001), and behavioural problems (n = 5,500; OR: 2.76; 95% CI: 2.11-3.60; p < 0.001) more than type 2 ROP at 18-24 months. Infants treated with anti-VEGF had higher odds of moderate cognitive impairment than the laser surgery group if adjusted data (gestational age, sex severe intraventricular haemorrhage, bronchopulmonary dysplasia, sepsis, surgical necrotising enterocolitis, and maternal education) were analysed [adjusted OR (aOR): 1.93; 95% CI: 1.23-3.03; p = 0.04], but not for cerebral palsy (aOR: 1.29; 95% CI: 0.65-2.56; p = 0.45). All outcomes were adjudged with a "very low" certainty of evidence.

Conclusion and relevance

Infants with "any ROP" had higher risks of cognitive impairment or intellectual disability, cerebral palsy, and behavioural problems. Anti-VEGF treatment increased the risk of moderate cognitive impairment. These results support the association of ROP and anti-VEGF treatment with adverse neurodevelopmental outcomes.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42022326009.

Association of sedation and anesthesia on cognitive outcomes in very premature infants: a retrospective observational study

PURPOSE

Cognitive outcomes in preterm infants may be adversely affected by use of sedation and anesthetic agents. We investigated the associations between anesthetics/sedatives and full-scale intelligence quotient (FSIQ) measured at 36 months corrected age (CA) in very preterm infants (born < 29 weeks gestational age).

METHODS

This retrospective cohort study included preterm infants born at < 29 weeks of gestation between 1 January 2006 and 31 December 2012, whose cognitive outcomes were assessed at 36 months CA. Imputed and complete case univariable and adjusted multivariable linear regressions were used to investigate the associations between FSIQ [standardized to mean (standard deviation) 100 (15)] and exposure to volatile anesthetics, propofol, benzodiazepines, barbiturates, and ketamine. These agents were the subject of a 2016 warning from regulatory authorities in the USA recommending caution for administration to children and pregnant women.

RESULTS

A total of 731 infants met the inclusion criteria. Unadjusted associations were -7 (95% confidence interval [CI], -10 to -4; P < 0.001) and -6 (95% CI, -10 to -3; P < 0.001) FSIQ points with exposure to warned medications using imputed and complete case analyses, respectively. Imputed and complete case adjusted associations between FSIQ and warned medications were -3 (95% CI, -7 to 0; P = 0.045) and -4 (95% CI, -8 to 0; P = 0.071) FSIQ points, respectively. Adjusted associations between volatile anesthetic exposure only and FSIQ were -3 (95% CI, -6 to 0; P = 0.072) and -5 (95% CI, -9 to -2; P = 0.004) FSIQ points using imputed and complete case data sets, respectively. FSIQ was not associated with opioid exposure.

CONCLUSION

Exposure of very preterm infants to anesthetics/sedatives on the United States Food and Drug Administration warning list was associated with a decrease in FSIQ points at 36 months CA. There was no association between opioid exposure and FSIQ.

Retrospective evaluation of ophthalmological and neurological outcomes for infants born before 24 weeks gestational age in a Swedish cohort

OBJECTIVES

To retrospectively evaluate ophthalmological and neurological outcomes in a Swedish cohort of infants born before 24 weeks gestational age (GA) and explore risk factors for visual impairment.

SETTING

Eye and paediatric clinics in Sweden.

PARTICIPANTS

Infants screened for retinopathy of prematurity (ROP) (n=399), born before 24 weeks GA, 2007-2018. Cases were excluded if ophthalmological follow-up records could not be traced.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcomes were ophthalmological, including visual acuity (VA), refractive error, strabismus, nystagmus and cerebral visual impairment (CVI). Secondary outcomes comprised neonatal and neurological morbidities. Data were retrospectively retrieved from medical records.

RESULTS

The 355 assessed children had a median GA of 23 weeks and 2 days and a median birth weight of 565 g. At the last available ophthalmological examination, the median age was 4.8 years (range 0.5-13.2 years). Nystagmus was recorded in 21.1%, strabismus in 34.8%, and 51.0% wore spectacles. Seventy-three of 333 (21.9%) were visually impaired, defined as being referred to a low vision clinic and/or having a VA less than 20/60 at 3.5 years of age or older. ROP treatment was a significant risk factor for visual impairment (OR 2.244, p=0.003). Visually impaired children, compared with children without visual impairment, more often had neurological deficits such as intellectual disability 63.8% versus 33.3% (p<0.001), epilepsy 21.1% versus 7.5% (p=0.001) and autism spectrum disorders 32.8% versus 20.9% (p=0.043). Nine of the 355 children had been diagnosed with CVI.

CONCLUSIONS

Children born before 24 weeks GA frequently had visual impairment in association with neurological deficits. CVI was rarely diagnosed. A multidisciplinary approach for the evaluation and habilitation of these vulnerable infants is warranted. National follow-up guidelines need to be developed and implemented.

Neurosensory Alterations in Retinopathy of Prematurity: A Window to Neurological Impairments Associated to Preterm Birth

Retinopathy of prematurity (ROP) is one of the main blinding diseases affecting preterm newborns and is classically considered a vascular disorder. The premature exposure to the extrauterine environment, which is hyperoxic in respect to the intrauterine environment, triggers a cascade of events leading to retinal ischemia which, in turn, makes the retina hypoxic thus setting off angiogenic processes. However, many children with a history of ROP show persistent vision impairment, and there is evidence of an association between ROP and neurosensory disabilities. This is not surprising given the strict relationship between neuronal function and an adequate blood supply. In the present work, we revised literature data evidencing to what extent ROP can be considered a neurodegenerative disease, also taking advantage from data obtained in preclinical models of ROP. The involvement of different retinal cell populations in triggering the neuronal damage in ROP was described along with the neurological outcomes associated to ROP. The situation of ROP in Italy was assessed as well.

Vision Abnormalities in Children and Young Adults With Cerebral Palsy; A Systematic Review

AIM

The current study was designed to provide detailed information on the prevalence of ocular abnormalities in patients with cerebral palsy (CP).

METHODS

Four international online scientific databases, including Web of Science, PubMed, Scopus, and Google Scholar were systemically searched. First, the titles of the articles were evaluated, and if relevant, their abstracts and full texts were reviewed. The quality of the studies was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist.

RESULTS

A total of 147 articles were found in the initial search. After applying the exclusion criteria, 65 articles were chosen for further review, from which 17 articles, comprising a total of 1734 patients with CP ranging in age from birth to 22 years, passed the STROBE quality check and were included in this review. The prevalence of ocular abnormalities in the CP patients reported in the evaluated studies ranged between 34% to 100%, with refractive error, strabismus, and nystagmus exhibiting the greatest overall prevalence at 52%, 48%, and 11%, respectively in this population.

CONCLUSION

Early ocular assessment of children with CP is essential for an accurate diagnosis, personalized rehabilitation and performing early interventions to improve their visual function.

Severe Retinopathy of Prematurity Associated With Neurodevelopmental Disorder in Children

OBJECTIVE

This study aimed to investigate whether severe retinopathy of prematurity (ROP) could be an association factor for neurodevelopmental disorders in premature infants without other risk factors-such as congenital anomalies, birth injuries, and neurological diseases-that may cause developmental delay.

METHODS

We used health claims data recorded between 2007 and 2018 in the Korean National Health Insurance Service (KNHIS) database. We recruited a total of 18,256 premature infant born between 2007 and 2008 without congenital anomaly or birth injury (with ROP 6,995, without ROP 11,261) and divided them into four groups as follows: Group A, 209 extremely premature infants [gestational age (GA) < 28] with mild ROP; Group B, 75 extremely premature infants (GA < 28) with severe ROP; Group C, 6,510 other premature infants (28 ≤ GA <37)with mild ROP; and Group D, 201 other premature infants (28 ≤ GA < 37) with severe ROP. Using regression analysis, we analyzed whether there was a correlation between ROP prevalence, severity, and developmental delay in premature infants without other risk factors.

RESULTS

The prevalence of developmental delay, according to GA and ROP severity, was higher in patients with severe ROP than in the other patients. The prevalence gradually decreased after birth. Among extremely premature infants with ROP, those with severe ROP had a 3.082-fold higher association with neurodevelopmental complications than those with mild ROP (p < 0.001). Compared with other premature infants with ROP, those with severe ROP had a 3.269-fold higher association with neurodevelopmental complications than those with mild ROP.

CONCLUSION

The severity of ROP may be associated with neurodevelopmental disorders in premature infants.

Severe Retinopathy of Prematurity Is Not Independently Associated With Worse Neurodevelopmental Outcomes in Preterm Neonates

Purpose: To evaluate the relationship between retinopathy of prematurity (ROP) severity and neurodevelopmental outcomes in premature neonates at 0-36 months corrected age. Methods: A retrospective chart review was performed on 228 neonates screened for ROP at the UCLA Mattel Children's Hospital between 2011 and 2018. Demographic information, clinical outcomes, ROP severity (no ROP, type 1 ROP, type 2 ROP), and Bayley-III neurodevelopmental scores were collected. Infants were grouped into corrected age cohorts (0-12, 12-24, and 24-36 months) to assess neurodevelopmental outcomes with increasing age. Within each age cohort, ANOVA and Chi-Square testing were used to detect differences in birth characteristics and neurodevelopmental scores between infants with type 1 ROP, type 2 ROP, or no ROP. Univariable analyses assessed the relationship between ROP severity and neurodevelopmental outcomes within each age cohort. A multivariable analysis was then performed to determine if ROP severity remained significantly associated with worse neurodevelopmental scores after controlling for birth weight (BW), intraventricular hemorrhage grade (IVH), health insurance type, male sex, and age at Bayley testing. Results: Without controlling for factors associated with prematurity, neonates with type 1 ROP had poorer cognition (p = 0.001) and motor (p = 0.006) scores at ages 0-12 months and poorer cognition (p = 0.01), language (p = 0.04) and motor (p = 0.04) scores at ages 12-24 months than infants without ROP, but no significant differences were detected at ages 24-36 months. After adjusting for BW, IVH, insurance type, male sex, and age at Bayley testing, ROP severity was no longer associated with worse neurodevelopmental scores in any domain. Conclusion: This study emphasizes that poorer neurodevelopmental outcomes in preterm neonates are most likely related to lower birthweight, associated co-morbidities of prematurity, and socioeconomic factors such as health insurance, not severity of ROP itself.

Analysis of Brain Injury Biomarker Neurofilament Light and Neurodevelopmental Outcomes and Retinopathy of Prematurity Among Preterm Infants

IMPORTANCE

Circulating levels of neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) are important in the course of brain injury in adults, but longitudinal postnatal circulating levels in preterm infants have not been investigated.

OBJECTIVES

To examine postnatal longitudinal serum levels of NfL and GFAP in preterm infants during the first 15 weeks of life and to explore possible associations between these biomarkers, neonatal morbidities, and neurodevelopmental outcomes at 2 years.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from 3 clinical studies, including 221 infants born before 32 weeks gestational age (GA) from 1999 to 2015; neurodevelopmental outcomes were evaluated in 120 infants. Data were collected at tertiary-level neonatal intensive care units in Gothenburg, Lund, and Uppsala, Sweden. Data analysis was conducted from January to October 2020.

EXPOSURE

Preterm birth.

MAIN OUTCOMES AND MEASURES

Serum NfL and GFAP levels, retinopathy of prematurity (ROP), intraventricular hemorrhage, and Bayley Scales of Infant Development II and III at 2 years of age, analyzed by multivariate logistic regression measured by odds ratio (OR), and receiver operating characteristic curve (ROC) analysis. Area under the curve (AUC) was also measured.

RESULTS

The 221 included infants (108 [48.9%] girls) had a mean (SD) GA at birth of 26.5 (2.1) weeks and a mean (SD) birth weight of 896 (301) grams. NfL levels increased after birth, remaining high during the first 4 weeks of life before declining to continuously low levels by postnatal age 12 weeks (median [range] NfL level at birth: 58.8 [11.5-1371.3] ng/L; 1 wk: 83.5 [14.1-952.2] ng/L; 4 wk: 24.4 [7.0-306.0] ng/L; 12 wk: 9.1 [3.7-57.0] ng/L). In a binary logistic regression model adjusted for GA at birth, birth weight SD score, Apgar status at 5 minutes, and mode of delivery, the NfL AUC at weeks 2 to 4 was independently associated with any ROP (OR, 4.79; 95% CI, 2.17-10.56; P < .001). In an exploratory analysis adjusted for GA at birth and sex, NfL AUC at weeks 2 to 4 was independently associated with unfavorable neurodevelopmental outcomes at 2 years corrected age (OR per 10-unit NfL increase, 1.07; 95% CI, 1.02-1.13; P = .01). Longitudinal GFAP levels were not significantly associated with neonatal morbidity or neurodevelopmental outcome.

CONCLUSIONS AND RELEVANCE

In this study, high NfL levels during the first weeks of life were associated with ROP and poor neurodevelopmental outcomes at 2 years of age. Associations between NfL and later neurovascular development in infants born prematurely should be investigated further.

Visual assessment of preterm and full-term infants under the age of 12 months using the Preverbal Visual Assessment questionnaire

BACKGROUND

Infants develop many complex visual competences within the first 12 months of life. Premature infants are at high risk for abnormal visual and neurological development. Clinical medical history or neurologic evaluation do not give enough information on visual maturation in infants under 12 months of age.

AIMS

To compare visual maturation between preterm and full-term infants aged under 12 months, using the Preverbal Visual Assessment questionnaire (PreViAs).

STUDY DESIGN

Retrospective cross-sectional analysis.

SUBJECTS

Infants aged under 12 months, who visited our rehabilitation department for early intervention. Infants were categorized as either preterm or full-term, and assigned to one of three subgroups (0-4 months, 4-8 months, 8-12 months) according to corrected or chronological age.

OUTCOME MEASURES

PreViAs scores.

RESULTS

There were 200 preterm and 225 full-term infants analyzed. The mean global PreViAs scores among preterm infants were significantly lower than among full-term infants in all age groups (0-4 months: p = 0.033, 4-8 months: p = 0.005, and 8-12 months: p = 0.008). The mean global scores and four subdomain scores of the PreViAs were significantly lower (p < 0.001) in very preterm (under 32-weeks gestational age) and very low birth weight (under 1500 g birth weight) than in moderate-to-late preterm infants (between 32- to 37- weeks gestational age) and infants with birth weight above 1500 g. Patent ductus arteriosus, retinopathy of prematurity, and birth weight (percent) showed significant correlation with PreViAs global scores.

CONCLUSION

PreViAs is a useful tool for visual assessment of infants under 12 months, especially in high-risk infants.

Severity of retinopathy of prematurity was associated with a higher risk of cerebral dysfunction in young adults born extremely preterm

AIM

This Swedish study evaluated whether the severity of retinopathy of prematurity (ROP) in extremely preterm infants was related to their overall outcome in young adulthood.

METHODS

We followed 39 individuals born between 1988 and 1993 at less than 28 gestational weeks, included in the Stockholm Neonatal Project. A total of 19 were treated for severe ROP, and 20 had no or mild ROP. They were assessed for general cognitive abilities and mental health at 18 years of age and compared with 23 term-born controls. Visual acuity was examined at 21-25 years. They were asked about their education and everyday life.

RESULTS

The 19 individuals with severe treated ROP had lower visual acuity and higher risk for intellectual deficits, cerebral palsy and neuropsychiatric diagnoses than those with no or mild ROP and the term controls. Three were visually impaired, none were blind. They were less physically active than the other groups and had more problems finding their way around. However, nine were at university.

CONCLUSION

Young adults treated for severe ROP had more problems resulting from cerebral dysfunction than those with no or mild ROP and term-born controls. Retinal and brain pathologies in the extremely preterm infant constitute different expressions of neurovascular disease.

Retinopathy of prematurity in infants without fetal growth restriction is decreased with the progression of acute histologic chorioamnionitis: New observation as a protective factor against retinopathy of prematurity

INTRODUCTION

IGF-1 deficiency in prenatal period is known to be a definite pathophysiology of retinopathy of prematurity(ROP), which is more frequent in infants with fetal growth restriction(FGR). Of note, recent reports demonstrated intra-amniotic inflammation(IAI) closely linked to acute histologic chorioamnionitis(acute-HCA) is associated with a decrease in intact-form of IGFBP-1, ultimately rising the probability of an increase in IGF-1. Therefore, we hypothesized ROP in preterm-infants without FGR would be decreased with the progression of acute-HCA.

METHODS

The frequency of ROP was examined in 85 singleton preterm-infants(24.5weeks ≤ gestational-age[GA] at delivery<30weeks) due to either preterm-labor and intact-membranes(PTL) or preterm premature rupture of membranes(preterm-PROM) without FGR(birth-weight<5th percentile for GA). Patients were divided according to the progression of inflammation in extra-placental membranes(EPM) and the progression of inflammation in chorionic-vessel(CV) and umbilical-cord(UC).

RESULTS

1) ROP was present in 40%(34/85) of study-population; 2) Of note, there was a significant stepwise-decrease in ROP with the progression of inflammation in EPM(inflammation-free EPM vs. inflammation restricted to CD vs. amnionitis; 55.6%[15/27]vs.39.5%[17/43]vs.13.3%[2/15]) and the progression of inflammation in CV and UC(inflammation-free CV and UC vs. inflammation restricted to CV and umbilical vessels vs. inflammation in Wharton's jelly[WJ]; 49.2%[29/59]vs.25.0%[3/12]vs.14.3%[2/14])(each-for P < 0.05, Chi-square test and each-for P < 0.01, linear-by-linear association); 3) Multiple logistic-regression analysis demonstrated amnionitis(Odds-Ratio 0.120, 95%Confidence-Interval 0.022-0.654, P = 0.014) and inflammation in WJ(Odds-Ratio 0.124, 95%Confidence-Interval 0.022-0.694, P = 0.018) were independent protective-factors against ROP.

DISCUSSION

ROP in preterm-infants due to PTL or preterm-PROM without FGR is decreased with the progression of acute-HCA. This finding may be an evidence to suggest the progression of acute-HCA is closely associated with reducing the pathophysiology of ROP.

Serious neonatal morbidities are associated with differences in DNA methylation among very preterm infants

Background

Infants born very preterm are more likely to experience neonatal morbidities compared to their term peers. Variations in DNA methylation (DNAm) associated with these morbidities may yield novel information about the processes impacted by these morbidities.

Methods

This study included 532 infants born < 30 weeks gestation, participating in the Neonatal Neurobehavior and Outcomes in Very Preterm Infants study. We used a neonatal morbidity risk score, which was an additive index of the number of morbidities experienced during the NICU stay, including bronchopulmonary dysplasia (BPD), severe brain injury, serious neonatal infections, and severe retinopathy of prematurity. DNA was collected from buccal cells at discharge from the NICU, and DNAm was measured using the Illumina MethylationEPIC. We tested for differential methylation in association with the neonatal morbidity risk score then tested for differentially methylated regions (DMRs) and overrepresentation of biological pathways.

Results

We identified ten differentially methylated CpGs (α Bonferroni-adjusted for 706,278 tests) that were associated with increasing neonatal morbidity risk scores at three intergenic regions and at HPS4, SRRD, FGFR1OP, TNS3, TMEM266, LRRC3B, ZNF780A, and TENM2. These mostly followed dose–response patterns, for 8 CpGs increasing DNAm associated with increased numbers of morbidities, while for 2 CpGs the risk score was associated with decreasing DNAm. BPD was the most substantial contributor to differential methylation. We also identified seven potential DMRs and over-representation of genes involved in Wnt signaling; however, these results were not significant after Bonferroni adjustment for multiple testing.

Conclusions

Neonatal DNAm, within genes involved in fibroblast growth factor activities, cellular invasion and migration, and neuronal signaling and development, are sensitive to the neonatal health complications of prematurity. We hypothesize that these epigenetic features may be representative of an integrated marker of neonatal health and development and are promising candidates to integrate with clinical information for studying developmental impairments in childhood.

Associations between VEGF isoforms and impending retinopathy of prematurity

BACKGROUND/OBJECTIVE

Vascular Endothelial Growth Factor (VEGF) is the main driver of angiogenesis during neurodevelopment (i.e., brain and retina). VEGF165 and VEGF121 are the two most prevalent human VEGF isoforms. Although retinopathy of prematurity (ROP), a neuroretinal disorder, is associated with VEGF dysregulation, little is known about the interaction of VEGF isoforms on neuroretinal angiogenesis. We hypothesized that: (a) A specific VEGF165/VEGF121 correlation, at a given time point, is associated with normal retinal development (no ROP) and (b) An altered correlation, of such, is associated with aberrant retinal development (ROP). Utilizing pre-collected dried blood spots (DBS) from <1-week-old preterm infants, we aimed to determine whether correlations between VEGF165 and VEGF121 precede the diagnosis of early stage, non-proliferative ROP (NP-ROP).

METHODOLOGY

We conducted a case/control study, utilizing DBS from 65 preterm infants. We measured DBS levels of VEGF165 on the Mesoscale Discovery Platform and VEGF121 via Cloud Clone Elisa Assay.

RESULTS

In infants with NP-ROP, VEGF165 is significantly higher in males (than females). In infants without ROP, there is a significant correlation between VEGF165 and VEGF121 in females (but not males). In infants with NP-ROP, the opposite is so; there is a significant correlation between VEGF165 and VEGF121 in males (but not females).

CONCLUSIONS

This pilot study, utilizing de-identified data, suggests the potential importance of examining interactions between VEGF isoforms, at <1 week after birth, to better understand ROP development. Our study also suggests that retinal angiogenesis may not be a sex-neutral process. A prospective study is needed to confirm our novel findings.

The association between high levels of luteinizing hormone and proliferative retinopathy of prematurity in female preterm infants

BACKGROUND

Luteinizing hormone (LH) and human chorionic gonadotropin (hCG), generally considered reproductive hormones, have potent proangiogenic properties. Both of these hormones and their joint receptor (CG/LH receptor) are found in the human eye. We hypothesized that an excess of these hormones is associated with proliferative retinopathy of prematurity (P-ROP).

METHODS

Dried blood spots (DBS) were used to perform a cross-sectional study of infants (gestational age of <26 weeks) with and without P-ROP, born in Michigan between August 1, 2012, and March 15, 2015. The DBS were collected at 1 week and 4 weeks of age from 45 preterm infants (27 no-ROP and 18 P-ROP). The DBS were linked to hospital records and then deidentified. ICD-9 codes were used to identify P-ROP cases. Hormones levels were measured via electrochemiluminescence assays on the Meso Scale Discovery platform. Associations between hormone levels at 1 and 4 weeks of age and the presence or absence of P-ROP were assessed.

RESULTS

In female infants, we noted a trend toward higher LH levels in ROP cases at week 1 (P = 0.11) and significantly higher LH levels in cases at week 4 (P = 0.03). In male infants, no ROP-related differences in LH levels were found at either time point. For hCG levels, no associations with P-ROP were found in either sex at either time point.

CONCLUSIONS

The association of high LH with P-ROP in female but not male infants raises the possibility that there are sex-specific hormonal determinants of aberrant retinal angiogenesis.

Antecedents of Objectively Diagnosed Diffuse White Matter Abnormality in Very Preterm Infants

BACKGROUND

Diffuse white matter abnormality (diffuse excessive high signal intensity) is the most common finding on structural brain magnetic resonance imaging (MRI) at term-equivalent age in very preterm infants. Yet, there remains a large gap in our understanding of the etiology of diffuse white matter abnormality. Our objective was to evaluate perinatal and neonatal inflammation-associated antecedents of diffuse white matter abnormality on MRI.

METHODS

We prospectively enrolled 110 very preterm infants born at ≤31 weeks gestational age and collected data on multiple perinatal/neonatal exposures, especially inflammation initiating-illnesses. We performed structural MRI at term-equivalent age and quantified the volume of diffuse white matter abnormality objectively. Multivariable regression was used to identify clinical antecedents of diffuse white matter abnormality.

RESULTS

The mean (S.D.) birth gestational age of the final study sample of 98 very preterm infants was 28.3 (2.5) weeks. Multiple inflammation initiating-illnesses were associated with diffuse white matter abnormality in univariate analyses. In multivariable linear regression analyses controlling for gestational age, severe retinopathy of prematurity (P < 0.001) and bronchopulmonary dysplasia (P = 0.006) were independent risk factors, whereas maternal treatment with 17-hydroxyprogesterone (P < 0.001) was protective of later development of objectively quantified diffuse white matter abnormality.

CONCLUSIONS

We identified several perinatal and neonatal antecedent clinical factors associated with diffuse white matter abnormality. Although we found some support for inflammation as a common underlying mechanism, larger studies are needed to validate inflammation as a potential common pathway to the development of diffuse white matter abnormality in very preterm infants.

Retinopathy of prematurity, visual and neurodevelopmental outcome, and imaging of the central nervous system

Recent findings indicate that retinopathy of prematurity (ROP), presently classified by clinical examinations of retinal vascular tissue, is associated with structural alterations of the central nervous system. Such alterations may be the correlate of the association between ROP and impaired long-term neurocognitive and visual development. The advent of imaging techniques such as structural and diffusion tensor magnetic resonance imaging of the brain, and optical coherence tomography of the retina, will allow the complete visual system to be characterized in greater detail. It has been suggested that ROP may be not only a vascular, but a neurovascular disease, being part of a spectrum that includes pathological development in both the retinal and cerebral neurovascular interphase. We review the present knowledge in the field and point to future directions for research to tackle these questions.

Cumulative evidence for association of sepsis and retinopathy of prematurity

BACKGROUND

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease affected by multiple factors such as infection and preterm birth. The role of sepsis in the development of ROP remains controversial. This systematic review and meta-analysis aimed to identify the impact of sepsis on ROP.

METHODS

The PubMed, Embase, and Cochrane Library databases were searched using terms related to sepsis and ROP. Cohort or case-control studies that reported the association of sepsis and ROP were eligible. The odds ratios (ORs) together with the 95% confidence interval (CI) were extracted from the studies or computed by authors if not provided.

RESULTS

Thirty-four studies were ultimately included in this meta-analysis. The pooled results showed that sepsis increased the risk for the development of any stage ROP (OR = 2.16; 95% CI: 1.65-2.82). Both early onset (OR = 2.50; 95% CI: 1.97-3.18) and late-onset (OR = 1.37; 95% CI: 1.22-1.55) sepsis were associated with severe ROP. Furthermore, both bacterial sepsis (OR = 1.74; 95% CI: 1.21-2.50) and fungal sepsis (OR = 2.96; 95% CI: 2.05-4.28) were also found to be associated with severe ROP.

CONCLUSION

Sepsis increased the risk of any stage ROP, especially for the severe ROP. Further high-quality clinical studies are needed to eliminate heterogeneity and publication bias to validate these findings.

Extreme prematurity, treated retinopathy, bronchopulmonary dysplasia and cerebral palsy are significant risk factors for ophthalmological abnormalities at 6.5 years of age

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.

[Electrophysiological characteristics of the retina in children with cicatrical retinopathy of prematurity]

Visual impairment in children with regressive retinopathy of prematurity (ROP) are diverse and widespread.

PURPOSE

to describe the electrophysiological characteristics of the retina in children with I-V stages of regressive ROP.

MATERIAL AND METHODS

The study included children with stages I-V aged 5 to 17 (in the disease stages of IV and V - with reattachment of the retina after surgical treatment of its detachment). Patients with concomitant diseases of the eye were excluded from the study. The main group included 133 children (163 eyes) aged 5 to 17 (mean age 7.2±0.3). Gestation age was 30.0±0.2 weeks, birth weight - 1368.0±46.6g. The control group consisted of 55 age-matched children. Standard electroretinogram (ERG) was performed in all study subjects. The amplitude-time characteristics of maximum and photopic response a- and b-waves were evaluated, and the b/a-index was calculated.

RESULTS

Visual acuity of 0.6 or higher was observed in 18 eyes (54.5%) of children with stage I-II ROP and significantly less in the disease stages of III and IVa - 29.5% and 15.6% respectively (p<0.01: Φ=2,717-3,663). In patients with IVb-V stages in 94.1% of cases visual acuity was lower than 0.1. Anamnesis showed significant decrease in photopic ERG starting with active period of stage III ROP. The retinal function further progressively decreased with stages. b/a index of maximum ERG increased proportionally to the severity of ROP active period. Core b/a index was significantly reduced in all stages of ROP (p<0.05).

CONCLUSION

Even the early stages of ROP have consequences for the functional status of the retina in premature infants; it is accompanied by significant disturbance of its electrogenesis.

Relation of Retinopathy of Prematurity to Brain Volumes at Term Equivalent Age and Developmental Outcome at 2 Years of Corrected Age in Very Preterm Infants

BACKGROUND

Retinopathy of prematurity (ROP) is a major complication of preterm birth and has been associated with later visual and nonvisual impairments.

OBJECTIVES

To evaluate relationships between any stage of ROP, brain volumes, and developmental outcomes.

METHODS

This study included 52 very preterm infants (gestational age [mean ± SD]: 26.4 ± 1.9 weeks). Total brain, gray matter, unmyelinated white matter (UWMV), and cerebellar volumes were estimated in 51 out of 52 infants by magnetic resonance imaging at term-equivalent age. Bayley Scales of Infant Development were used to assess developmental outcomes in 49 out of 52 infants at a mean corrected age of 24.6 months.

RESULTS

Nineteen out of 52 infants developed any stage of ROP. Infants with ROP had a lower median (IQR) UWMV (173 [156-181] vs. 204 [186-216] mL, p < 0.001) and cerebellar volume (18.3 [16.5-20] vs. 22.3 [20.3-24.7] mL, p < 0.001) than infants without ROP. They also had a lower median (IQR) mental developmental index (72 [56-83] vs. 100 [88-104], p < 0.001) and a lower psychomotor developmental index (80 [60-85] vs. 92 [81-103], p = 0.002). Brain volumes and developmental outcomes did not differ among infants with different stages of ROP.

CONCLUSION

Any stage of ROP in preterm infants was associated with a reduced brain volume and an impaired developmental outcome. These results suggest that common pathways may lead to impaired neural and neurovascular development in the brain and retina and that all stages of ROP may be considered in future studies on ROP and development.

Systemic Inflammation-Associated Proteins and Retinopathy of Prematurity in Infants Born Before the 28th Week of Gestation

Purpose

To assess the association between systemic levels of inflammation-associated proteins and severe retinopathy of prematurity (ROP) in extremely preterm infants.

Methods

We collected whole blood on filter paper on postnatal days 1, 7, 14, 21, and 28 from 1205 infants born before the 28th week of gestation, and measured the concentrations of 27 inflammation-associated, angiogenic, and neurotrophic proteins. We calculated odds ratios with 95% confidence intervals for the association between top quartile concentrations of each protein and prethreshold ROP.

Results

During the first three weeks after birth, high concentrations of VEGF-R1, myeloperoxidase (MPO), IL-8, intercellular adhesion molecule (ICAM)-1, matrix metalloproteinase 9, erythropoietin, TNF-α, and basic fibroblast growth factor were associated with an increased risk for prethreshold ROP. On day 28, high levels of serum amyloid A, MPO, IL-6, TNF-α, TNF-R1/-R2, IL-8, and ICAM-1 were associated with an increased risk. Top quartile concentrations of the proinflammatory cytokines TNF-α and IL-6 were associated with increased risks of ROP when levels of neuroprotective proteins and growth factors, including BDNF, insulin-like growth factor 1, IGFBP-1, VEGFR-1 and -2, ANG-1 and PlGF, were not in the top quartile. In contrast, high concentrations of NT-4 and BDNF appeared protective only in infants without elevated inflammatory mediators.

Conclusions

Systemic inflammation during the first postnatal month was associated with an increased risk of prethreshold ROP. Elevated concentrations of growth factors, angiogenic proteins, and neurotrophins appeared to modulate this risk, and were capable of reducing the risk even in the absence of systemic inflammation.

Retinopathy of prematurity: inflammation, choroidal degeneration, and novel promising therapeutic strategies

Retinopathy of prematurity (ROP) is an important cause of childhood blindness globally, and the incidence is rising. The disease is characterized by initial arrested retinal vascularization followed by neovascularization and ensuing retinal detachment causing permanent visual loss. Although neovascularization can be effectively treated via retinal laser ablation, it is unknown which children are at risk of entering this vision-threatening phase of the disease. Laser ablation may itself induce visual field deficits, and there is therefore a need to identify targets for novel and less destructive treatments of ROP. Inflammation is considered a key contributor to the pathogenesis of ROP. A large proportion of preterm infants with ROP will have residual visual loss linked to loss of photoreceptor (PR) and the integrity of the retinal pigment epithelium (RPE) in the macular region. Recent studies using animal models of ROP suggest that choroidal degeneration may be associated with a loss of integrity of the outer retina, a phenomenon so far largely undescribed in ROP pathogenesis. In this review, we highlight inflammatory and neuron-derived factors related to ROP progression, as well, potential targets for new treatment strategies. We also introduce choroidal degeneration as a significant cause of residual visual loss following ROP. We propose that ROP should no longer be considered an inner retinal vasculopathy only, but also a disease of choroidal degeneration affecting both retinal pigment epithelium and photoreceptor integrity.

Optical coherence tomography of the preterm eye: from retinopathy of prematurity to brain development

Preterm infants with retinopathy of prematurity are at increased risk of poor neurodevelopmental outcomes. Because the neurosensory retina is an extension of the central nervous system, anatomic abnormalities in the anterior visual pathway often relate to system and central nervous system health. We describe optical coherence tomography as a powerful imaging modality that has recently been adapted to the infant population and provides noninvasive, high-resolution, cross-sectional imaging of the infant eye at the bedside. Optical coherence tomography has increased understanding of normal eye development and has identified several potential biomarkers of brain abnormalities and poorer neurodevelopment.

Antecedents and correlates of visual field deficits in children born extremely preterm

AIM

We sought to identify the antecedents and correlates of visual field deficits (VFDs) at age 2 years among infants born before the 28th week of gestation.

METHODS

The visual fields of 1023 infants were assessed by confrontation at age 2 years. We compared the ante-and postnatal characteristics and exposures of the 65 infants with a VFD to their peers who did not have a VFD. We used time-oriented logistic regression risk models to assess the associations of potential antecedents and correlates with a VFD.

RESULTS

In the final regression model, VFD was associated with maternal consumption of aspirin during the current pregnancy, recurring/persistent acidemia during the first 3 postnatal days, cerebral ventriculomegaly seen on neonatal ultrasound, prethreshold retinopathy of prematurity (ROP), and supplemental oxygen and ventilator dependence at 36 weeks post-menstrual age. Birth before the 27th week was also associated with increased risk, but its significance was diminished by the addition of postnatal variables.

CONCLUSION

In this sample of extremely preterm born infants, antenatal as well as early and late postnatal characteristics and exposures are associated with an increased risk of having a VFD. Our study adds to our knowledge about the complex etiology of visual deficits of prematurity, and supports a multifactorial cause of these deficits.

Poorer neurodevelopmental outcomes associated with cystoid macular edema identified in preterm infants in the intensive care nursery

PURPOSE

To evaluate the association between cystoid macular edema (CME) observed in very preterm infants and developmental outcomes at 18 to 24 months corrected age.

DESIGN

Cohort study.

PARTICIPANTS

Infants born at or less than 1500 g or at or less than 30 weeks postmenstrual age who underwent screening for retinopathy of prematurity (ROP) in an intensive care nursery.

METHODS

Bedside handheld spectral-domain optical coherence tomography (SD OCT; Envisu, Bioptigen, Inc, Research Triangle Park, NC) imaging was obtained from preterm infants who were being screened for ROP and graded for presence of CME, central foveal thickness (CFT), inner nuclear layer thickness, and foveal-to-parafoveal thickness ratio. At 18 to 24 months corrected age, the children were assessed with the Bayley Scales of Infant and Toddler Development, Third Edition.

MAIN OUTCOME MEASURES

Scores on the Bayley cognitive, language, and motor subscales.

RESULTS

Among 77 children with SD OCT imaging, 53 were evaluated with the Bayley Scales. Compared with children who did not have CME as infants (n=22), the mean score for children who had CME (n=31) was 7.3 points (95% confidence interval [CI], -15.5 to 0.9; P=0.08) lower on the cognitive subscale, 14.1 points (95% CI, -22.7 to -5.5; P=0.002) lower for the language subscale, and 11.5 points (95% CI, -21.6 to -1.3; P=0.03) lower for the motor subscale. Differences were maintained after adjusting for gestational age and birth weight. Severity of CME, as assessed by foveal-to-parafoveal thickness ratio, within the CME group correlated with poorer cognitive (R2=0.16, P=0.03) and motor (R2=0.15, P=0.03) development.

CONCLUSIONS

Cystoid macular edema observed on SD OCT in very preterm infants screened for ROP is associated with poorer language and motor skills at 18 to 24 months corrected age. Evaluation of the retina with SD-OCT may serve as an indicator of neurodevelopmental health for very preterm infants in the intensive care nursery.