Retinopathy of prematurity: Risk factors and variability in Canadian neonatal intensive care units

Red Blood Cell Transfusion for Incidence of Retinopathy of Prematurity: Prospective Multicenter Cohort Study

Background

Retinopathy of prematurity (ROP) is a leading cause of visual impairment and blindness in preterm infants.

Objective

This study sought to investigate the association between red blood cell (RBC) transfusion and ROP in very preterm infants (VPIs) to inform clinical strategies for ROP prevention and treatment.

Methods

We designed a prospective multicenter cohort study that included VPIs and follow-up data from January 2017 to December 2022 at 3 neonatal clinical medicine centers. They were categorized into a transfusion group (infants who received an RBC transfusion within 4 wk) and a nontransfusion group. The relationship between RBC transfusion and ROP incidence was assessed using binary logistic regression, with subgroup analyses based on gestational age, birth weight, sex, and sepsis status. Inverse probability of treatment weighting and propensity score matching were applied to account for all potential confounding factors that could affect ROP development, followed by sensitivity analysis.

Results

The study included 832 VPIs, including 327 in the nontransfusion group and 505 in the transfusion group. The transfusion group had a lower average birth weight and gestational age and a greater incidence of ROP, ≥stage 2 ROP, and severe ROP. Logistic regression analysis revealed that the transfusion group had a significantly greater risk of ROP (adjusted odds ratio [aOR] 1.70, 95% CI 1.14-2.53, P=.009) and ≥stage 2 ROP (aOR 1.68, 95% CI 1.02-2.78, P=.04) but not severe ROP (aOR 1.75, 95% CI 0.61-5.02, P=.30). The trend analysis also revealed an increased risk of ROP with an increasing number of transfusions and a larger volume of blood transfused (P for trend<.001). Subgroup analyses confirmed a consistent trend, with the transfusion group at a higher risk for ROP across all subgroups. Inverse probability of treatment weighting and propensity score matching analyses supported the initial findings.

Conclusions

For VPIs, RBC transfusion significantly increases the risk of ROP, and the risk increases with an increasing number of transfusions and volume of blood transfused.

Incidence, Risk Factors and Development of Retinopathy of Prematurity in Mid-Preterm and Late-Preterm Infants

PURPOSE

To evaluate the incidence, risk factors, and development of retinopathy of prematurity (ROP) in midpreterm and late-preterm infants born at 32 to 36 6/7 weeks of gestational age.

METHODS

The ophthalmic examination findings and risk factors of 5,477 preterm infants who underwent ophthalmological examination were evaluated retrospectively. The rates of any stage and severe ROP (requiring treatment) development and treatment options were recorded. The risk factors were analyzed by using logistic regression analysis.

RESULTS

A total of 5,477 infants were included in the study, of whom 2,715 (49.57%) were mid-preterm and 2,762 (50.43%) were late-preterm. The rates of any stage and severe ROP were 8.2% (n = 223) and 0.6% (n = 15) in mid-preterm infants, respectively. In late-preterm infants, the rate of any stage ROP was 2.1% (n = 59), and no severe ROP was detected. There was no significant difference in mean birth weight in mid-preterm infants between infants with any stage ROP and severe ROP (P = .104). Of the 15 infants (0.3%) who required treatment, 14 (0.2%) infants had laser photocoagulation, 1 (0.01%) had intravitreal bevacizumab, and 2 (0.03%) had additional therapy (laser photocoagulation and intravitreal bevacizumab). In logistic regression analysis, a significant association was found between treatment requirement and transport from an external center (P < .001, ß = 0.04).

CONCLUSIONS

Although ROP development rates decrease as birth weight and gestational age increase, late-preterm infants should be examined for ROP at least once, especially those born in low-income countries because ROP development can still be observed. [J Pediatr Ophthalmol Strabismus. 2024;61(5):351-357.].

Retinal Image Dataset of Infants and Retinopathy of Prematurity

Retinopathy of prematurity (ROP) represents a vasoproliferative disease, especially in newborns and infants, which can potentially affect and damage the vision. Despite recent advances in neonatal care and medical guidelines, ROP still remains one of the leading causes of worldwide childhood blindness. The paper presents a unique dataset of 6,004 retinal images of 188 newborns, most of whom are premature infants. The dataset is accompanied by the anonymized patients' information from the ROP screening acquired at the University Hospital Ostrava, Czech Republic. Three digital retinal imaging camera systems are used in the study: Clarity RetCam 3, Natus RetCam Envision, and Phoenix ICON. The study is enriched by the software tool ReLeSeT which is aimed at automatic retinal lesion segmentation and extraction from retinal images. Consequently, this tool enables computing geometric and intensity features of retinal lesions. Also, we publish a set of pre-processing tools for feature boosting of retinal lesions and retinal blood vessels for building classification and segmentation models in ROP analysis.

Hyperbilirubinemia and retinopathy of prematurity: a retrospective cohort study

Retinopathy of prematurity (ROP) is a vasoproliferative retinal disease in preterm infants. Oxidative stress plays a key role in the pathogenesis of ROP. Due to its antioxidant effects, bilirubin has been proposed to be protective against ROP. This study explored the association between hyperbilirubinemia and ROP. We analyzed a 10-year cohort from a neonatal intensive care unit in Milan, Italy, including 1606 infants born under 32 weeks and/or < 1500 g. Data from 1606 infants meeting specific inclusion criteria were reviewed. Eighty infants were excluded due to lack of data, 1526 were deemed eligible for analysis, and 1269 had hyperbilirubinemia requiring phototherapy. There was a higher incidence of ROP among infants with hyperbilirubinemia (13.8%) versus those without (7.8%, p<0.01). Infants with any ROP, non-severe or severe ROP, were exposed to hyperbilirubinemia for a significantly higher number of days compared with those without ROP. Each additional day of exposure increases the risk of developing any ROP by 5%, non-severe ROP by 4%, and severe ROP by 6%. However, this correlation was not observed in infants with gestational age less than 27 weeks and/or body weight less than 1000 g.    Conclusion: Our data show that hyperbilirubinemia requiring phototherapy is associated with an increased risk of developing ROP. However, severe hyperbilirubinemia and ROP share many of their risk factors. Therefore, rather than being a risk factor itself, hyperbilirubinemia may be a surrogate for other risk factors for ROP.    Clinical Trial Registration: NCT05806684. What is Known: • The development of retinopathy of prematurity (ROP) is influenced by several critical risk factors, including low gestational age, low birth weight, supplemental oxygen use, and increased oxidative stress. • In vitro, unconjugated bilirubin is an effective scavenger of harmful oxygen species and a reducing agent, highlighting its potential protective role against oxidative stress. What is New: • Hyperbilirubinemia requiring phototherapy was associated with an increased risk of developing ROP, but this association was not observed in the most vulnerable population of extremely preterm infants. • Every additional day of phototherapy for hyperbilirubinemia increases the risk of ROP by 5% for any ROP, 4% for non-severe ROP, and 6% for severe ROP.

Corneal Endothelial Morphology and Ocular Biometric Indexes in Premature Children With and Without Retinopathy of Prematurity

Purpose

The purpose of this study was to analyze human corneal endothelial cells (HCECs) morphology and ocular biometrics in premature (PM) children with or without retinopathy of prematurity (ROP).

Methods

Retrospective data on patient demographics, HCECs status, and ocular biometrics with at least 2 visits between 2016 and 2021 were reviewed. The main outcomes were endothelial cell density (ECD), coefficient of variation (CV), hexagonal cell ratio (HEX), central corneal thickness (CCT), axial length, anterior chamber depth, keratometry, corneal diameter, pupil diameter, and refraction status. Generalized estimating equation was used to evaluate the differences between PM no-ROP and ROP groups. We also analyzed the trend of ECD, CV, HEX, and CCT change with age between groups.

Results

The study included 173 PM patients without ROP and 139 patients with ROP. A total of 666 and 544 measurements were recorded in the PM no-ROP and ROP groups, respectively. The ROP group had higher spherical power, myopic spherical equivalent (SE), and steeper steep keratometry (K; P < 0.05). The ROP group had higher CV (P = 0.0144), lower HEX (P = 0.0012) and thicker CCT (P = 0.0035). In the HCECs parameters, the ROP group had slower ECD decrement (P < 0.0001), faster CV decrement (P = 0.0060), and faster HEX increment (P = 0.0001). A difference in corneal morphology changes between the ROP and PM no-ROP groups were prominent in patients with lower gestational age (GA) in the subgroup analysis.

Conclusions

Worse HCECs morphology and higher myopic status were initially observed in patients with prior ROP but not in PM patients with no-ROP. ECD and HCECs morphology improved with age, especially in patients with low GA.

Regional variations in retinopathy of prematurity incidence for preterm infants <32 weeks' gestation in China

OBJECTIVES

National-level data on the incidence of retinopathy of prematurity (ROP) in different regions of China is insufficient. This study aimed to compare ROP incidences and care practices in different regions of China and their relationship with regional gross domestic product (GDP) per capita.

STUDY DESIGN

Retrospective cohort study.

METHODS

All infants born at <32 weeks gestational age (GA) and admitted to 70 neonatal intensive care units (NICUs) from January 1, 2019, to December 31, 2020, were enrolled. Hospitals were categorised into three regional groups according to geographical locations and GDP per capita from high to low: Eastern, Central, and Western China. The incidence of death or ROP, and care practices were compared among the groups.

RESULTS

A total of 18,579 infants were enrolled. Median GA was 29.9 (interquartile range 28.4-31.0) weeks and birth weight was 1318.1 (317.2) g. The percentage of GA <28 weeks, complete administration of antenatal steroids, and weight gain velocity during NICU stay were highest in Eastern China and lowest in Western China (all P < 0.01). In Eastern, Central, and Western China, the rates of death or any stage of ROP were 33.3%, 38.5%, and 39.2%, respectively (P < 0.01).

CONCLUSIONS

There were considerable regional disparities in ROP incidence in preterm infants with GA <32 weeks in China. The incidence of death or ROP ranged from high to low in Western, Central, and Eastern China.

Erythrocyte transfusions are associated with retinopathy of prematurity in extremely low gestational age newborns

AIM

Retinopathy of prematurity (ROP) is a major morbidity in preterm infants causing visual impairment including blindness. Prevention and timely treatment are critical. We investigated the potential role of red blood cell (RBC) transfusions as risk factor for ROP development.

METHODS

Retrospective cohort study of data from 68 tertiary level neonatal intensive care units in Germany. Preterm infants born at 22 + 0 to 28 + 6 weeks of gestation between January 2009 and December 2021 were enrolled.

RESULTS

We included n = 12 565 infants. Prevalence of any ROP was 49.2% with most infants being diagnosed with stage 1 (21.5%) and 2 disease (17.2%). ROP stage 3 was present in 10.2%, stage 4 in 0.3%, and ROP requiring treatment in 6.6%. Infants with ROP had significantly more frequently a history of RBC transfusions. Adjusting for confounders, RBC transfusions were associated with increased odds of ROP (OR 1.4, p < 0.001), ROP progression (OR 2.1, p < 0.01) and ROP requiring treatment (OR 3.6, p < 0.001). Restrictive transfusion approaches correlated with decreased (OR 0.7, p < 0.001), liberal regimes with increased odds (OR 1.2, p = 0.001).

CONCLUSION

The present study confirmed an association of RBC transfusions and ROP. Our findings emphasise the need for anaemia prevention and critical re-evaluation of transfusion practices in preterm infants.

Jeddah Retinopathy of Prematurity (JED-ROP) Screening Algorithm

Background. The Jeddah retinopathy of prematurity (JED-ROP) algorithm, which is more specific to the population in Saudi Arabia, was established to decrease the number of infants screened without missing type 1 ROP cases. Methods. The data reviewed were birth weight (BW), gestational age (GA), weekly postnatal weight gain (PWG), and relevant perinatal risk factors. The sensitivities and specificities for detecting type 1 ROP were calculated. Results. Of the 502 infants included in the study, 148 developed ROP. The JED-ROP algorithm demonstrated 100% sensitivity and 38.9% specificity for recommending the screening of infants with GA ≤30 weeks and BW <1501 g and blood transfused <6 weeks and/or 3-week PWG <100 g in the type 1 ROP group. Conclusion. The JED-ROP algorithm can reduce the number of infants requiring ROP screening by 35.7% without missing type 1 ROP. The algorithm can be an adjunct to current national screening guidelines.

Retinopathy of prematurity: risk stratification by gestational age

OBJECTIVE

To identify gestational age (GA) specific risk factors for severe ROP (sROP).

STUDY DESIGN

Single-center cohort stratified by GA into <24 weeks, 24-26 weeks and ≥27 weeks.

RESULTS

132/1106 (11.9%) developed sROP. Time to full feeds was the only risk factor [HR 1.003 (1.001-1.006), p = 0.04] for infants<24 weeks GA. For infants 24-26 weeks GA, a higher GA was protective [HR 0.66 (0.51-0.85), p < 0.01], whereas steroids for bronchopulmonary dysplasia (BPD) [HR 2.21 (1.28-3.26), p < 0.01], patent ductus arteriosus (PDA) ligation [HR 1.99 (1.25-3.11), p < 0.01] and use of nitric oxide [HR 1.96 (1.11-3.30), p = 0.01] increased the hazard of sROP. Increasing birthweight was protective [HR 0.70 (0.54-0.89), p < 0.01] in infants ≥27 weeks GA. Cumulative hazard of sROP reached 1.0 by fifteen weeks for <24 weeks GA, 0.4 by twenty weeks for 24-26 weeks GA, and 0.05 by twenty weeks after birth for ≥27 weeks GA.

CONCLUSIONS

Risk factors, cumulative hazard, and time to sROP vary by GA.

Modifiable Risk Factors and Preventative Strategies for Severe Retinopathy of Prematurity

Severe ROP is characterized by the development of retinal fibrovascular proliferation that may progress to retinal detachment. The purpose of this report is to review five of the most common and well-studied perinatal and neonatal modifiable risk factors for the development of severe ROP. Hyperoxemia, hypoxia, and associated prolonged respiratory support are linked to the development of severe ROP. While there is a well-established association between clinical maternal chorioamnionitis and severe ROP, there is greater variability between histologic chorioamnionitis and severe ROP. Neonatal sepsis, including both bacterial and fungal subtypes, are independent predictors of severe ROP in preterm infants. Although there is limited evidence related to platelet transfusions, the risk of severe ROP increases with the number and volume of red blood cell transfusions. Poor postnatal weight gain within the first six weeks of life is also strongly tied to the development of severe ROP. We also discuss preventative strategies that may reduce the risk of severe ROP. Limited evidence-based studies exist regarding the protective effects of caffeine, human milk, and vitamins A and E.

The incidence and risk factors associated with the retinopathy of prematurity in a tertiary hospital using 10-year retrospective data

BACKGROUND

The study aimed to examine the incidence and risk factors associated with retinopathy of prematurity at Phramongkutklao Hospital.

METHODS

A retrospective review was conducted on the medical records of premature infants screened for retinopathy of prematurity between January 2011 and December 2021. The screening examination was performed on infants who met the screening criteria, and retinopathy of prematurity was diagnosed according to the International Classification of Retinopathy of Prematurity. Maternal, obstetric, neonatal, and medical data were retrieved. Logistic regression analysis was used to identify the risk factors associated with retinopathy of prematurity.

RESULTS

A total of 403 premature infants were screened. The mean ± SD birth weight and gestational ages were 1,538 ± 543 grams and 31 ± 3 weeks, respectively. The incidence of any retinopathy of prematurity and stages 2 and 3 were 13.6%, 3.5%, and 10.1%, respectively. Multiple logistic regression analysis demonstrated that gestational age (adjusted odds ratio = 1.98, 95% CI:1.15-3.39), low birth weight (adjusted odds ratio = 0.99, 95% CI: 0.99-1.00), and phototherapy (adjusted odds ratio = 0.41, 95% CI: 0.17-1.00) were significant factors associated with the development of retinopathy of prematurity, after controlling for other confounding factors.

CONCLUSIONS

The incidence of total retinopathy of prematurity cases in this population was 13.6%. Overall, retinopathy of prematurity cases classified as stage 2 equated to 3.5% and stage 3 to 4.1%. Our data suggest that factors associated with retinopathy of prematurity consist of birth weight, gestational age, and phototherapy.

Premature infants with gestational age less than 25 weeks require increased ophthalmology resources for retinopathy of prematurity

BACKGROUND

It is unclear how increasing survival of low gestational age (GA) infants affects ophthalmologic screening and treatment rates for retinopathy of prematurity (ROP). This study compared the examination and treatment rates of infants born at GA of <25 weeks and those born at GA of at least 25 weeks.

METHODS

This was a retrospective study of patients who met institutional ROP screening criteria and were admitted to two neonatal intensive care units (NICUs) from January 2017 to June 2020. Variables analyzed were GA, birth weight, number of ophthalmology examinations, worst stage of ROP, presence of type 1 ROP, and comorbidities associated with ROP. The χ², Fisher exact, and two-tailed t tests, as well as univariate and multivariable logistic regression, were used for statistical analysis.

RESULTS

Compared to the GA≥25 group, the GA<25 group had a higher number of total exams (10 vs 4.3 [P < 0.001]), higher average worst stage of ROP (1.4 vs 0.3 [P < 0.001]) and higher rate of type 1 ROP (21% vs 1.4% [P < 0.001]), as well as higher mortality (37% vs 8.11% [P < 0. 001]). Multivariable logistic regression analysis controlling for GA, sepsis, and number of transfusions revealed that only GA was significantly associated with developing type 1 ROP.

CONCLUSIONS

Infants with GA <25 weeks had more severe ROP and required significantly more ophthalmologic examinations than GA ≥25. It is important for ROP services to plan for this increased screening load, especially if the number of such lower-weight infants in their NICUs increases.

Trends in Retinopathy of Prematurity Care in the US 2009-2018: A Nationwide Analysis using National Inpatient Sample

PURPOSE

Retinopathy of prematurity (ROP) represents a leading cause of childhood blindness. The purpose of our study was to evaluate incidence, trends in cost and length of hospital stay, and risk factors for ROP using a publicly available population-based dataset, the National Inpatient Sample.

DESIGN

This cross-sectional study analyzed data from 2009 to 2018 using the National Inpatient Sample.

PARTICIPANTS

Premature neonates (n = 717 277) who met the screening criteria for ROP with gestational age of ≤ 30 weeks or birthweight (BW) of ≤ 1500 g were identified.

METHODS

Database analysis.

MAIN OUTCOME MEASURES

Incidence, demographics, risk factors for ROP development, trends in cost, and length of stay were evaluated.

RESULTS

In total, incidence of ROP increased from 11% in 2009 to 15% in 2018 (P < 0.001). Multivariate logistic regression model of ROP development showed its associations with female sex (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.10-1.17), Hispanic (OR, 1.10; 95% CI, 1.03-1.18), and Black (OR, 0.91; 95% CI 0.86-0.96) ethnicity. Neonates with lower BWs, particularly those in the 500- to 999-g subgroup (OR, 2.64; 95% CI, 2.44-2.85) and younger gestational ages, particularly those born between 25 and 28 weeks gestational age (OR, 2.41; 95% CI, 2.25-2.58), had increased risk of developing ROP. Comorbidities associated with the development of ROP were perinatal jaundice (OR, 1.84; 95% CI, 1.74-1.94), patent ducts arteriosus (OR, 1.67; 95% CI, 1.60-1.75), intraventricular hemorrhage (OR, 1.41; 95% CI, 1.35-1.48), perinatal infection (OR, 1.84; 95% CI, 1.74-1.94), and respiratory distress syndrome (OR, 1.05; 95% CI, 1.01-1.10).

CONCLUSIONS

Retinopathy of prematurity develops in about 1 of 10 premature infants and incidence has been shown to be increasing. Significant risk factors were female sex, Hispanic ethnicity, lower BW, younger gestational age, and systemic comorbidities, including perinatal jaundice, patent ductus arteriosus, intraventricular hemorrhage, perinatal sepsis, and respiratory distress syndrome.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Screening and Risk Factors for Retinopathy of Prematurity in a Tertiary Care Hospital in Cairo, Egypt

Purpose

To evaluate the retinopathy of prematurity (ROP) prevalence, risk factors and screening outcome in a tertiary hospital in Cairo, Egypt.

Methods

A prospective observational study was done in Neonatal Intensive Care Unit in Ain Shams University Hospital. A total of 159 premature infants were screened for ROP based on the most inclusive criteria reported to date. Screening included premature infants with gestational age (GA) of ≤34 weeks or birth weight (BW) of ≤2000 grams, or GA >34 weeks or BW >2000 grams, with multiple co-morbidities. The prevalence of ROP, plus disease and their correlation with risk factors of interest were studied.

Results

The GA of the included infants ranged from 27 to 36 weeks, mean (SD) 31.87 (± 1.81) weeks. The BW ranged from 640 to 3900 grams, mean (SD) 1784.71 (± 560.30) grams. The prevalence of ROP more than stage 0 was 25.8% (41 infants), 7.3% of the cases (11 infants) showed plus disease and 6.3% (10 infants) showed severe ROP requiring treatment. Of those, 2 cases (20%) fell outside the British Guideline's criteria for Screening. There was a highly significant (p < 0.0001) correlation between ROP more than stage 0 and low GA, low BW, mechanical ventilation, respiratory distress syndrome, necrotizing enterocolitis, intraventricular haemorrhage, and blood transfusion. No significant correlation was found between appearance of ROP more than stage 0 and gender (p = 0.911), patent ductus arteriosus (p =0.187), or sepsis (p =0.998).

Conclusion

ROP is a significant problem in the premature infants in Egypt. Extremely premature infants with lower BW are more prone to develop ROP. However, cases with higher GA and BW than mentioned in the British guidelines screening criteria especially with multiple comorbidities showed severe ROP requiring intervention, which implies the need to develop a screening guideline for the Egyptian population.

Incidence of retinopathy of prematurity treatment in extremely preterm infants in China

BACKGROUND

Retinopathy of prematurity (ROP) continues to be a major cause of visual impairment and blindness in premature infants and children.

OBJECTIVES

To investigate the incidence of severe ROP receiving treatment in extremely preterm (EP) infants in China over time. The risk factors for ROP treatment were also assessed.

METHODS

This was a multicentre retrospective study and a subanalysis of baseline data from the "Outcomes of EP infants in China 2010-2019" study. This study was conducted in 68 tertiary neonatal care centres from 31 provinces of China. Infants with a gestational age of 23⁰ -27⁶  weeks and admitted to a neonatal unit within the first 72 h of life between 2010 and 2019 were enrolled. Incidence of ROP was analysed in infants who survived to 32 weeks postmenstrual age and screened for ROP. Multivariable modified Poisson regression models were used to identify risk factors for ROP treatment.

RESULTS

Among 7295 eligible infants, 4701 (64.5%) survived to 32 weeks postmenstrual age and met ROP screening criteria. Of the 3756 infants who screened and with ROP data, 2320 (61.8%) developed ROP of any stage. The overall incidence of ROP treatment was 12.6%, decreasing from 45.5% at 23 weeks to 8.3% at 27 weeks. During the 10-year period, the incidence of ROP treatment did not change, although the incidence of any ROP increased over time. Independent risk factors associated with ROP treatment included lower gestational age, small for gestational age, multiple birth, severe intraventricular haemorrhage, patent ductus arteriosus and supplemental oxygen duration.

CONCLUSIONS

The incidence of EP infants receiving ROP treatment showed no change during this 10-year period in China. Prevention of prematurity and foetal growth restriction, judicious use of oxygen and reducing comorbidities are promising factors that may reduce the incidence of ROP needing treatment in these high-risk infants.

Evaluation of the prematurity retinopathy and other eye changes in the newborn

Objective

To assess the prevalence of ophthalmologic manifestations in newborns in a maternity hospital in the city of São Paulo, SP, and the main risk factors related with the development of retinopathy of prematurity.

Methods

A retrospective, longitudinal study with patients born from 2015 to 2017 who required ophthalmological evaluation. The research variables were obtained by analysis of the newborn medical charts.

Results

A total of 773 patients were studied. The sample consisted of 288 examinations performed by indication of gestational age ≤32 weeks: 118 (42.4%) in 2015, 105 (42.2%) in 2016, 65 (26.4%) cases in 2017. There were 329 evaluations indicated due to birth weight: 113 (40.6%) in 2015, 108 (43.4%) in 2016, and 108 (43.9%) in 2017. The prevalence of associated risk factors was 97 (34.9%) cases in 2015, 96 (38.6%) in 2016, and 54 (22%) in 2017, followed by mechanical ventilation with 82 (29.5%) cases in 2015, 64 (25.7%) in 2016 and 41 (16.7%) in 2017, and continuous positive airway pressure with 59 (21.2%) cases in 2015, 72 (28.9%) in 2016, and 46 (18.7%) in 2017. For the other indications, the evaluations performed due to congenital syphilis were the majority in the 3-year period of the study, with 55 (19.8%) newborns in 2015, 54 (21.7%) in 2016, and 59 (24.0%) in 2017. The most prevalent ophthalmologic diagnosis was retinopathy of prematurity, with 79 (35.3%) cases in 2015, 64 (32.2%) in 2016, and 41 (24.1%) in 2017.

Conclusion

Most neonates born in the organization do not present risk factors for ophthalmological manifestations. Retinopathy of prematurity was the disease with greater strength of association found in our study. For the other indications, the evaluations performed due to congenital syphilis prevail in the 3- year period of the study.

Increased Risk for Respiratory Complications in Male Extremely Preterm Infants: A Propensity Score Matching Study

BACKGROUND

Many factors can affect the clinical outcome of extremely premature infants (EPIs), but the effect of sex is paradoxical. This study used propensity score matching to adjust baseline information to reassess the clinical outcome of EPIs based on sex.

METHODS

A retrospective analysis was performed on EPIs admitted in the Department of Neonatology of the Third Affiliated Hospital of Guangzhou Medical University from 2011 to 2020. A propensity score matching (PSM) analysis was used to adjust the confounding factors including gestational age, birth weight, 1-minute Apgar score ≤ 3, withholding or withdrawing life-sustaining treatment(WWLST), mechanical ventilation, duration of mechanical ventilation, the mother with advanced age (≥35 years old), complete-course antenatal steroid therapy and hypertensive disorders of pregnancy. The survival rate at discharge and the incidence of major complications were evaluated between the male and female groups.

RESULTS

A total of 439 EPIs were included, and 240 (54.7%) infants were males. After matching the nine confounding factors, 148 pairs of infants were finally enrolled. There was no significant difference in the survival rate at discharge, as well as the mortality of activating treatment or WWLST between the two groups (all P>0.05). However, the incidence of respiratory distress syndrome, bronchopulmonary dysplasia (BPD), and moderate to severe BPD in the male group was significantly increased (all P<0.01), especially at birth weight between 750 and 999 grams.

CONCLUSIONS

The male EPIs have a higher risk of respiratory complications than females, particularly at 750 to 999 grams of birth weight.

The prenatal phase of retinopathy of prematurity

AIM

To explore the current literature on prenatal inflammation-associated risk factors for retinopathy of prematurity (ROP).

METHODS

Subjective summary of selected experimental and epidemiological publications that support the authors' central hypothesis that the aetiology of ROP begins before birth.

RESULTS

Based on current evidence we suggest that, contrary to current aetiological models, the process of ROP development begins with a prephase in utero. This beginning is likely initiated by inflammatory responses that are associated with intrauterine infection.

CONCLUSION

We propose a novel aetio-pathogenetic model of ROP and suggest that the effects of postnatal exposure to inflammatory stressors (resulting from infection or hyperoxia or both) as well as those of other pre- and postnatal contributors to the complex pathogenesis of ROP might be modified by the prenatal phase of the disease.

Five-year demographic profile of retinopathy of prematurity at a tertiary care institute in North India

Purpose:

The purpose of this study is to study the demographic profile and pattern of retinopathy of prematurity (ROP) at a tertiary care institute in India.

Methods:

An ambispective study from January 2013 to December 2017. Infants with birth weights (BWs) <1750 g and gestational ages <34 weeks were screened for ROP. Demographic details and ROP severity were recorded.

Results:

Data of 2595 of the 3697 infants screened were analyzed. The number of infants screened and treated for ROP increased from 190 and 29, respectively (2013), to 818 and 132, respectively (2017). The overall incidence of “any ROP” was 32.3%, and severe ROP was 17.7%. Though 39.5% of all infants were outborns (not born in the study center), severe ROP was present in 69.7% of these compared to 18.8% among inborns. Outborns with ROP had a higher mean BW (1308 g) compared to inborns (1202 g) (P < 0.01). ROP Stage 1 was seen in 12%, Stage 2 in 34%, Stage 3 in 13%, Stage 4 in 6%, Stage 5 in 14%, and aggressive posterior ROP (APROP) in 20%. APROP was seen in 16% of infants in 2013, 10% in 2014, 15% in 2015, 22% in 2016, and 28% in 2017. Infants with Stage 4B/Stage5 (15.6% of all ROP) were presented at a mean age of 7.5 months and all had no/delayed screening.

Conclusion:

Incidence of any ROP was 32.3% and was more common in outborns than inborns. The proportion of infants with APROP showed a rising trend over the years. Nearly 15.6% of infants were presented with stage4B/5 ROP due to delayed/absent screening.

Clinical Characteristics of Preterm Neonates with Aggressive Posterior Retinopathy of Prematurity

Purpose

We aimed to identify the risk factors that may predispose preterm neonates to develop aggressive posterior retinopathy of prematurity (APROP).

Methods

This retrospective case control study included 16 infants with APROP in zone 1 or posterior zone 2. Thirty-four gestational age and birth weight-matched controls with stage 2 or less ROP were included. We reviewed medical records on infant birth and postnatal characteristics.

Results

Patients who developed APROP had a significantly longer duration of caffeine therapy, were significantly more likely to be small for gestational age (SGA), and were more likely to have a positive blood culture than patients who developed less severe ROP. Patients with APROP who required retreatment had received inotropes for a longer duration of time, had received more plasma transfusions, were more likely to have IVH, and had a greater decrease in the serum hemoglobin during hospitalization.

Conclusion

Being SGA, receiving caffeine for a longer duration, and having culture-proven sepsis were associated with APROP. IVH, a low serum hemoglobin, the need for more plasma transfusions, and a longer duration of inotropes were associated with APROP which required retreatment.

Incidence and Risk Factors Associated with Retinopathy of Prematurity in Peru

Purpose

The purpose of this research is to determine retinopathy of prematurity (ROP) prevalence and possible risk factors associated with ROP development in newborns admitted to a neonatal unit of a Peruvian National Reference Hospital.

Patients and Methods

This retrospective study included 216 preterm infants. The data were collected between January 2016 and December 2018. All infants were examined according to Peruvian guidelines for screening and treatment of ROP. The association of clinical risk factors and the development of ROP was analyzed and predictive factors were determined.

Results

The study subjects were 216 preterm infants of which 72 had some stage of ROP (32 stage 1; 23 stage 2 and 17 stage 3) and 144 preterm infants without ROP. The incidence of ROP in preterm infants less than 32 weeks was 60.9%, while for those weighing less than 1500 g it was 71.6%. The factors associated with ROP were gestational age below 32 weeks, birth weight below 1500 grams, neonatal sepsis, oxygen therapy, mechanical ventilation, hyaline membrane disease, bronchopulmonary dysplasia, persistence of ductus arteriosus and intraventricular hemorrhage. Exclusive breastfeeding was found to play a protective role against ROP. Binary logistic regression analysis found that only gestational age below 32 weeks (OR, 2.637; 95% CI, 1.04–6.69), weight below 1500 grams (OR, 4.377; 95% CI, 1.75–10.92), neonatal sepsis (OR, 6.517; 95% CI, 2.81–15.14), vaginal delivery (OR, 3.748; 95% CI: 1.54–9.14), and the presence of hyaline membrane disease (OR, 3.58; 95% CI, 1.47–8.74) are predictors of ROP.

Conclusion

The incidence of ROP among very low birth weight infants was 71.6%. Infants with weight below 1500 grams, neonatal sepsis, presence of hyaline membrane disease whose mother had vaginal delivery are at risk for the development of ROP. Thus, preventing premature births and encouraging exclusive breastfeeding are two main ways to prevent ROP.

Stable incidence but regional differences in retinopathy of prematurity in Norway from 2009 to 2017

PURPOSE

To explore the changes over time and regional differences in the incidence of retinopathy of prematurity (ROP) in a national cohort of infants born <28 weeks' gestational age (GA).

METHODS

A population-based study of infants with GA <28 weeks in Norway from 2009 to 2017. Prospectively collected data on clinical variables and outcomes were obtained from the Norwegian Neonatal Network.

RESULTS

Of 1499 live-born infants transferred to a neonatal intensive care unit, 1156 were discharged alive. Four-hundred and fifty-eight infants (39.6%) had ROP, 152 (13.1%) had severe ROP, and 110 (9.5%) were treated for ROP. Eleven hundred infants (95.2%) had complete data sets. In a model comprising region of primary care, GA [odds ratios (OR): 0.65; 95% CI: 0.55-0.77], growth velocity (OR: 1.10; 95% CI: 1.00-2.00), medically treated patent ductus arteriosus (OR: 1.80; 95% CI: 1.19-2.72), weeks of supplemental oxygen (OR: 1.07; 95% CI: 1.03 to 1.11) and region of primary care (OR: 4.95; 95% CI: 3.05-8.04 for the pair of regions with the highest estimated OR) were significantly associated with severe ROP. Additionally, institutional differences for severe ROP were found, with ORs from 0.41 (95% CI: 0.05-3.23) to 5.36 (95% CI: 3.05-9.43) using the largest institution as reference. Incidences were stable over time after adjusting for GA. A larger proportion was treated with anti-vascular endothelial growth factor after 2011.

CONCLUSIONS

The incidence of severe ROP was stable between 2009 and 2017 in Norway. Regional and institutional differences need to be explored in future studies.

Perinatal events predicting retinopathy of prematurity in extremely pre-term infants

BACKGROUND

Extremely preterm infants are peculiar in regard to their risk of retinopathy of prematurity (ROP). In this study, we aim to study insults that may affect extremely preterm infants, including prenatal, at birth, and postnatal insults and their effect on the development of ROP.

METHODS

This study used the data from Prematurity and Respiratory Outcomes Program (PROP). All included infants with a gestational age of 23 0/7 to 28 6/7 weeks using best obstetrical estimate. We included stressful events and/or modifiable variables that may affect the normal development. We used multiple regression analysis in our statistical analysis.

RESULTS

We included a total of 751 infants in our study. The mean birth weight for the included sample was 915.1 (±232.94) grams. 391 (52.1%) Infants were diagnosed with ROP. We found a significant negative correlation between ROP development and birth weight (p < 0.001), with a correlation coefficient of - 0.374. We found that the need for prophylactic indomethacin (OR 1.67), the occurrence of air leaks (OR: 2.35), ventilator-associated pneumonia (OR: 2.01), isolated bowel perforations (OR: 3.7), blood culture-proven sepsis (OR: 1.5), other infections (OR: 1.44), and receiving ventricular shunt (OR: 2.9) are significantly associated with the development of ROP.

CONCLUSIONS

We believe this study included the largest number of factors studied in the largest sample of extremely premature infants. We recommend a screening program for extremely preterm infants that takes into account a scoring system with higher scores for complicated condition.

Retinopathy of Prematurity and Assisted Reproductive Technology: Is There an Association?

Purpose

This study aimed to determine the incidence of retinopathy of prematurity (ROP) and to assess whether assisted reproductive technology (ART) is a risk factor for ROP independent of the generation of multiple births by determining the occurrence and severity of ROP and the need for treatment. We will also evaluate other risk factors associated with the development of ROP among preterm infants.

Patients and Methods

We conducted a retrospective chart review for all premature infants who were screened for ROP according to the screening guidelines of the American Academy of Ophthalmology and born at King Abdulaziz University Hospital from 2015 to 2019. In addition to ophthalmological results, data on gestational age (GA), birth weight (BW), type of pregnancy (singleton or multiple), type of conception (natural or ART), infantile factors, and maternal factors were recorded.

Results

A total of 229 preterm babies met our criteria. The mean GA at birth was 29.35 weeks. Notably, 175 neonates were conceived naturally and 54 were conceived by ART. Furthermore, 33 infants in the natural conception group were products of multiple pregnancies, as were 49 infants in the ART group. ROP was noted in 96 of 229 infants (41.92%). No significant difference was found in the occurrence of ROP between multiple neonates in the natural and ART groups. However, ART birth babies in general were significantly associated with the development of ROP (P=0.045). On multiple regression analysis, early GA, low BW, and extended oxygen therapy were the variables most significantly associated with ROP (P≤0.001).

Conclusion

In our sample, ART in multiple birth babies per se did not seem to be a risk factor for ROP. However, ART babies were more prone to develop ROP than natural conception birth babies, which seemed to be more severe.

A Good Way to Reduce Screening for Retinopathy of Prematurity: Development of the ROP Model in a China Preterm Population

Importance: Retinopathy of prematurity (ROP) is a preventable cause of blindness in children. Without treatment, more than 45% of eyes may suffer permanent vision loss. Current ROP screening guidelines, which include a range of birth weights (BWs) and gestational ages (GAs), may require screening many low-risk preemies who might develop severe ROP. Method: All high-risk infants in the neonatal intensive care unit (NICU) of the First Affiliated Hospital of Zhengzhou University from 2017 to 2021 were included in this retrospective cohort study. Each of the 27 candidate risk factors was evaluated in univariate analysis and adjusted for known risk factors (i.e., GA and BW). The significant results were analyzed in a backward selection multivariate logistic regression model. Receiver operating characteristic (ROC) curves and a nomogram were drawn. Results: The study included 2,040 infants who underwent ROP screening. The weight gain rate [OR, 2.65; 95% confidence interval (CI), 1.49-1.21 ≤ 12 g/d vs. > 18 g/d; P = 0.001], blood transfusion (OR, 2.03; 95% CI, 1.14-3.64; P = 0.017), invasive mechanical ventilation (OR, 1.74; 95% CI, 1.15-2.66; P = 0.009) and N-terminal segment of pro-B-type natriuretic peptide (NT-proBNP) ≥ 25,000 ng/L (OR, 1.51; 95% CI, 1.00-2.28; P = 0.048) were four new statistically independent risk factors in addition to GA and BW. The area under the curve (AUC) of the final multivariate model was 0.90 (95% CI, 0.88-0.92; P < 0.001). Conclusions and Relevance: These findings add to our understanding of ROP screening because they include all eligible infants rather than only high-risk infants, as in previous studies. Under the control of BW and GA, low weight gain rate, increased number of blood transfusion, invasive mechanical ventilation and NT-proBNP ≥ 25,000 ng/L were "new" statistically independent risk factors for ROP. The ROP risk can be calculated manually or represented by a nomogram for clinical use.

Higher incidence of retinopathy of prematurity in extremely preterm infants associated with improved survival rates

AIM

This study assessed possible reasons for the increasing incidence of retinopathy of prematurity (ROP) since mid-2015 at our institution.

METHODS

Retrospective analysis of all preterm infants born July 2013 to June 2017 with a gestational age (GA) <29 completed weeks admitted to the neonatal intensive care unit at the University Hospital Zurich during the first 28 days of life. The primary outcome measures were severest ROP stage. Statistical analysis was performed using generalised additive models in R.

RESULTS

During the study period, survival increased in extremely preterm infants. Significant predictors for severest ROP stage were GA, days of mechanical ventilation and multiple gestation (P = .0322). A composite of severe comorbidities had no significant effect on severest ROP stage. GA was identified as the only significant risk factor the for severest ROP stage (P = .0045).

CONCLUSION

Increased survival rate of extremely preterm infants was associated with an increased incidence of ROP at our institution. Despite the increase, the incidence is still very low compared with other countries. No other additive factors were identified.

Incidence and Risk Factors for Retinopathy of Prematurity in Tabuk City, KSA

PURPOSE

Retinopathy of prematurity (ROP) is becoming a leading cause of preventable blindness. The current study aimed to assess ROP and its risk factors in Tabuk City, Northern Kingdom of Saudi Arabia.

METHODS

A retrospective study was conducted in King Khalid Hospital, Tabuk City, Saudi Arabia. The premature infants' records during the period of January 2016 to April 2018 were approached. One hundred and eight records were eligible; the infants' gestational age, weight, if received oxygen, surfactant use, blood transfusion, intraventricular hemorrhage, and patent ductus arteriosus were reported. Chi-square test was used to compare premature infants and their counterparts regarding various risk factors. P < 0.05 was considered statistically significant.

RESULTS

Out of 108 premature infants, 33.3% had ROP (Many were sightthreatening [stages required treatment] and more than twothirds involving both eyes); a statistically significant difference (P < 0.05) was evident between infants with prematurity, and low birth weight. No significant differences were found regarding other risk factors (P > 0.05). Only 8.3% received interventional therapy.

CONCLUSION

ROP is common in King Khalid Hospital, which is the referral tertiary hospital in Tabuk city, KSA . The low birth weight is a significant risk factor to develop ROP. Many of ROP cases were sightthreatening (cases that required treatment) and most cases involving both eyes. Treatment availability at Tabuk city is recommended, instead of referral to another centers especially among those with low weight at birth.

Effect of red blood cell transfusion on the development of retinopathy of prematurity: A systematic review and meta-analysis

BACKGROUND

The effect of red blood cell (RBC) transfusion on retinopathy of prematurity (ROP) is difficult to establish, because ROP may also be influenced by other factors. Therefore, we carried out a systematic review and meta-analysis to explore the relationship between RBC transfusion and the development of ROP.

METHODS

The PubMed, Embase, Cochrane Library and Web of Science databases were searched from their inception to September 1, 2019. Observational studies that reported the relationship between RBC transfusion and ROP after adjusting for other potential risk factors were included. The combined result was analyzed by a random effect model. Heterogeneity and publication bias were tested, and sensitivity analysis was performed.

RESULTS

Of the 2628 identified records, 18 studies including 15072 preterm infants and 5620 cases of ROP were included. A random effect model was used and revealed that RBC transfusion was significantly associated with ROP (pooled OR = 1.50, 95% CI: 1.27-1.76), with moderate heterogeneity among the included studies (I2 = 44.2%). Subgroup analysis indicated that RBC transfusion was more closely related to ROP in the group with a gestational age (GA) ≤32 weeks (OR = 1.77, 95% CI: 1.29-2.43) but not in the groups with a GA ≤34 weeks (OR = 1.36, 95% CI: 0.85-2.18) or a GA <37 weeks (OR = 1.25, 95% CI: 0.86-1.82). No obvious publication bias was found based on the funnel plot and Egger's test. Removing any single study did not significantly alter the combined result in the sensitivity analysis.

CONCLUSIONS

Our study revealed that RBC transfusion is an independent risk factor for the development of ROP, especially in younger preterm infants. However, there seemed to be no evidence to support an effect of RBC transfusion on ROP in older groups. Further studies addressing this issue in older preterm neonates are warranted.

Trends in sex-specific differences in outcomes in extreme preterms: progress or natural barriers?

OBJECTIVE

To examine the differences and trends of outcomes of preterm boys and girls born at <29 weeks' gestation.

DESIGN

A retrospective cohort study.

SETTING

Data collected by the Canadian Neonatal Network.

PATIENTS

Neonates born at <29 weeks' gestation between January 2007 and December 2016.

MAIN OUTCOME MEASURES

We examined rate differences in mortality, major morbidities (bronchopulmonary dysplasia, severe brain injury, retinopathy of prematurity, necrotising enterocolitis and late-onset sepsis) and care practices (antenatal steroids, magnesium sulfate, maternal antibiotics, ventilation and surfactant administration) between boys and girls and evaluated trends in these rate differences over the study period. Our primary outcome was a composite of mortality and any one of the five morbidities.

RESULTS

Our study included 8219 boys and 6934 girls with median gestational age of 26 (IQR 25-28) weeks. The composite of death or major morbidity was more common in boys (adjusted risk ratio 1.07, 95% CI 1.05 to 1.10) and remained higher in boys over the study period. The gap between boys and girls for mortality, however, decreased over time: the slope for boys was -0.043 (95% CI -0.071 to -0.015) and for girls was -0.012 (95% CI -0.045 to 0.020) (p=0.04). All other morbidities remained higher in boys. Care practices changed at similar rates between the sexes.

CONCLUSION

The difference between the mortality rates for boys and girls decreased over the study period but the difference between rates of the major morbidities was unchanged. More research is needed to understand biological differences and outcome disparities.

New modifications of Swedish ROP guidelines based on 10-year data from the SWEDROP register

BACKGROUND/AIMS

During the last decade, improved neonatal care has resulted in increased survival of the most immature infants and improved health of more mature infants. We hypothesise that this has affected incidence and treatment of retinopathy of prematurity (ROP), enabling guidelines for screening to be modified.

METHODS

In Sweden, all infants with gestational age (GA) at birth ≤30 weeks are screened for ROP. Results are registered in a web-based register, Swedish National ROP Register, with a coverage rate of 97%. Incidence of ROP and frequency of treatment, aspects on natural course of ROP and number of examinations, are calculated in relation to GA at birth in infants born during 2008-2017.

RESULTS

Of 7249 infants, 31.9% (2310) had ROP and 6.1% (440) were treated. No infant with GA 30 weeks was treated. Incidence of ROP remained similar, but frequency of treatment increased (p=0.023). Over time, GA and birth weight were reduced in infants with ROP and with treated ROP. In the most immature infants, postmenstrual age was lower and postnatal age was higher when any ROP and stage 3 ROP were first detected (p<0.001). At treatment, postmenstrual but not postnatal age of the infant was associated with GA (p<0.001). During the 10-year period, 46 038 examinations were performed.

CONCLUSION

Modification of Swedish guidelines is proposed, including only infants with a GA of <30 weeks and postponing the first examination with 1 week in infants with GA 26-29 weeks. This would spare many infants from stressful examinations and reduce eye examinations with at least 20%.

Primary prevention of ROP and the oxygen saturation targeting trials

Reducing the burden of visual morbidity from retinopathy of prematurity (ROP) begins with primary prevention, and improvements in neonatal care with a positive impact on ROP are possible in all settings. Strategies range from rigorous adoption of inexpensive evidence-based protocols, for example on temperature control, prevention of sepsis and support for breast-milk feeding, through to comprehensive quality improvement programmes, and fostering team work and camaraderie. Oxygen monitoring is essential for very preterm infants receiving supplementary oxygen. The Neonatal Oxygenation Prospective Meta-analysis (NeOProM) collaboration has reported analysis of five trials of oxygen saturation (SpO₂) targeting in very preterm infants and shown that a SpO₂ target of 85-89% compared to 91-95% was associated with increased mortality (on average 28 extra deaths for every 1000 infants treated). Adopting a SpO₂ target higher than 85-89% might increase the risk of ROP for some infants, highlighting the importance of pursuing all other means of prevention.

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.

Case control study of risk factors and ophthalmological outcomes of very low birth weight infants with Type 1 retinopathy of prematurity

INTRODUCTION

We evaluated the risk factors associated with Type 1 retinopathy of prematurity (ROP) in very low birth weight (VLBW) infants and compared ophthalmologic outcomes between cases with Type 1 ROP who received treatment and gestational age-matched controls with mild or no ROP not requiring treatment.

METHODS

This was a retrospective case-control study of VLBW infants born in National University Hospital, Singapore, from January 2001 to December 2013. 17 cases with Type 1 ROP were each matched for gestational age with controls who had either mild (below Stage 2) or no ROP. Antenatal, perinatal and postnatal variables, as well as childhood ophthalmologic outcomes, were collected from their clinical records and analysed.

RESULTS

The number of packed cell transfusions and highest fraction of inspired oxygen given at weeks 7-10 were found to be statistically significant on multivariate analysis (p = 0.045 and p = 0.049, respectively). None of the infants had blindness or retinal detachment, and there were no significant differences in refractive errors between the groups at 1-4 years of age. Strabismus at four years of age was more common in the group with Type 1 ROP (p = 0.023).

CONCLUSION

Increased episodes of blood transfusions and chronic lung disease requiring high oxygen supplementation at 7-10 weeks of life are significant risk factors associated with Type 1 ROP in VLBW infants in our study. Strabismus at four years is more common in this group of patients. This study highlights the importance of long-term ophthalmologic surveillance for these high-risk children.

Perinatal Risk Factors for the Retinopathy of Prematurity in Postnatal Growth and Rop Study

Objective: To evaluate perinatal risk factors for retinopathy of prematurity (ROP), in a large, broad-risk cohort of premature infants. Study design: Secondary analysis of data from the Postnatal Growth and ROP (G-ROP) Study, a retrospective cohort study of infants undergoing ROP examinations at 29 North American hospitals in 2006-2012. Results: Among 7483 infants, 3224 (43.1%) had any ROP and 931 (12.4%) had severe ROP (Type 1 or 2 ROP). In multivariable logistic regression analysis, significant risk factors for any ROP were lower birth weight (BW, odds ratio (OR) = 5.2, <501 g vs. >1250 g), younger gestational age (GA, OR = 32, <25 vs. >29 weeks), 1-min Apgar score <4 (OR = 1.2), race (OR = 1.6, White vs. Black), outborn (OR = 1.5), and delivery room intubation (OR = 1.3); and for severe ROP were lower BW (OR = 20, <501 g vs. >1250 g), younger GA (OR = 30, <25 vs. >29 weeks), male (OR = 1.5), Hispanic ethnicity (OR = 1.8), race (OR = 1.6, White vs. Black), outborn (OR = 1.6), and delivery room intubation (OR = 1.6). Together, these factors predicted well for any ROP (area under ROC curve (AUC) = 0.87) and severe ROP (AUC = 0.89), but BW and GA were the dominant factors for ROP (AUC = 0.86) and severe ROP (AUC = 0.88). Conclusions: Based on the largest report to date with detailed ROP data from infants meeting current screening guidelines, ROP risk is predominantly determined by the degree of prematurity at birth, with other perinatal factors contributing minimally.

Effect of birth weight on retinopathy of prematurity in discordant twin pairs

Purpose:

Since twin pairs with discordance have equal gestational age (GA), discordant twins may constitute an appropriate group to investigate the specific effect that birth weight (BW) has on the development of retinopathy of prematurity (ROP). The present study aims to investigate the effect of BW on any and severe stages of ROP development in twin pairs.

Methods:

Fifty-two discordant twin pairs (104 preterms) born ≤32 gestational weeks, who were diagnosed with a minimum of 18% discordance between their BWs, were retrospectively analyzed. Twin pairs were separated into two groups based on the BW of each pair. The rate of any stage of ROP, Type 1 ROP, and perinatal risk factors were compared statistically among twin pairs.

Results:

The rate of any stage of ROP and Type 1 ROP was 24.0% and 4.8% in the whole group, respectively. A statistically significant difference was shown between lower and higher BW groups at any stage of ROP development (34.6% vs. 13.4%, P = 0.02). However, no difference was observed in Type 1 ROP development (7.7% vs. 1.9%, P = 0.17). No significant differences were found between twin pairs regarding neonatal morbidities. The number of small GA (SGA) infants in the smaller twin group was statistically higher than larger group and regression analysis showed that being SGA had significant correlation with any stage of ROP (odds ratio: 4.98, P = 0.02).

Conclusion:

This study showed that BW serves an effective role at any stage of ROP development in discordant twin pairs; however, no significant difference in terms of Type 1 ROP.

Association between sepsis and retinopathy of prematurity: a systematic review and meta-analysis

OBJECTIVE

To explore the association between sepsis and retinopathy of prematurity (ROP) in premature infants.

DESIGN

A systematic review and meta-analysis.

DATA SOURCES

We performed a systematic search of PubMed, the Cochrane Library and Embase from 1 January, 2000, to 1 January, 2018, with no language restrictions and reported the relationship between sepsis and ROP.

ELIGIBILITY CRITERIA

Original observational studies, including cohort studies and case-control studies.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently completed the study selection and data extraction. The OR and corresponding 95% CI were used to measure the risk of sepsis in patients with ROP. The heterogeneity between studies was evaluated using Cochran's Q test and the I2 statistic. The Newcastle-Ottawa Scale was adopted to evaluate the quality of each of the included studies, and the Grading of Recommendations Assessment, Development and Evaluation approach was used to assess the quality of the evidence.

RESULTS

Sixteen studies with a total sample size of 12 466 premature infants and 2494 cases of ROP were included in this meta-analysis. Adjusted analysis showed that sepsis was closely related to any stage of ROP (OR = 1.57, 95% CI 1.31 to 1.89) and severe stage of ROP (OR = 2.33, 95% CI 1.21 to 4.51) in premature infants, with 56.3% and 81.8% heterogeneity, respectively. Subgroup analyses showed that heterogeneity was obvious in prospective cohort studies (I2 = 62.1%, p<0.001). In a sensitivity analysis, we found that removing any single study did not significantly change the overall effect value. The quality of the evidence was rated as low for both any stage of ROP and severe stage of ROP.

CONCLUSIONS

Sepsis increases the risk of ROP in preterm infants. However, considering that all included studies are observational and causality can rarely be established, additional evidence is needed to substantiate this finding and provide advice for practice.

Risk Factors for Retinopathy of Prematurity in Premature Born Children

INTRODUCTION

Retinopathy of Prematurity (ROP) represent disease of the eye in premature born children which affects immature blood vessels of the retina during their development. The emergence of retinopathy of prematurity depends on the interaction of multiple factors, such as: gestational age, low birth weight, hypoxia, duration of oxygen supplementation, respiratory distress syndrome, twin pregnancy, anemia, blood transfusions, sepsis, intraventricular hemorrhage, hypotension, hypothermia, etc. If remain unrecognized and untreated it can cause severe visual impairment and blindness in children, but can also be prevented with timely screening.

GOALS

To establish the number of patients with development of retinopathy of prematurity active forms in the observed time period and examine which risk factors have most significant impact on its origin.

MATERIAL AND METHODS

In a clinical, retrospective study we observed a total of 80 premature born children in the period from January to May 2015 with regard to listed risk factors identified for eye examination.

RESULTS

From a total of 80 premature newborns sample included 48.8% male and 51.2% female children. The active form of ROP developed in 6.2% of cases, while in 93.8% of cases there was a spontaneous resolution. Patients who developed active form of ROP have significantly younger gestational age (26.4±1.5 weeks) and lower birth weight (874±181 grams), lower Apgar score in the first and fifth minute and were longer on oxygen therapy (20±3.4 days).

CONCLUSION

Of the potential risk factors that could affect the development of ROP active form following factors have a statistically significant influence: early gestational age, low birth weight, lower Apgar score and prolonged oxygen therapy (p <0.05).

Retinopathy of prematurity: a review of risk factors and their clinical significance

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

Validation of the Colorado Retinopathy of Prematurity Screening Model

Importance

The Colorado Retinopathy of Prematurity (CO-ROP) model uses birth weight, gestational age, and weight gain at the first month of life (WG-28) to predict risk of severe retinopathy of prematurity (ROP). In previous validation studies, the model performed very well, predicting virtually all cases of severe ROP and potentially reducing the number of infants who need ROP examinations, warranting validation in a larger, more diverse population.

Objective

To validate the performance of the CO-ROP model in a large multicenter cohort.

Design, Setting, Participants

This study is a secondary analysis of data from the Postnatal Growth and Retinopathy of Prematurity (G-ROP) Study, a retrospective multicenter cohort study conducted in 29 hospitals in the United States and Canada between January 2006 and June 2012 of 6351 premature infants who received ROP examinations.

Main Outcomes and Measures

Sensitivity and specificity for severe (early treatment of ROP [ETROP] type 1 or 2) ROP, and reduction in infants receiving examinations. The CO-ROP model was applied to the infants in the G-ROP data set with all 3 data points (infants would have received examinations if they met all 3 criteria: birth weight, <1501 g; gestational age, <30 weeks; and WG-28, <650 g). Infants missing WG-28 information were included in a secondary analysis in which WG-28 was considered fewer than 650 g.

Results

Of 7438 infants in the G-ROP study, 3575 (48.1%) were girls, and maternal race/ethnicity was 2310 (31.1%) African American, 3615 (48.6%) white, 233 (3.1%) Asian, 40 (0.52%) American Indian/Alaskan Native, and 93 (1.3%) Pacific Islander. In the study cohort, 747 infants (11.8%) had type 1 or 2 ROP, 2068 (32.6%) had lower-grade ROP, and 3536 (55.6%) had no ROP. The CO-ROP model had a sensitivity of 96.9% (95% CI, 95.4%-97.9%) and a specificity of 40.9% (95% CI, 39.3%-42.5%). It missed 23 (3.1%) infants who developed severe ROP. The CO-ROP model would have reduced the number of infants who received examinations by 26.1% (95% CI, 25.0%-27.2%).

Conclusions and Relevance

The CO-ROP model demonstrated high but not 100% sensitivity for severe ROP and missed infants who might require treatment in this large validation cohort. The model requires all 3 criteria to be met to signal a need for examinations, but some infants with a birth weight or gestational age above the thresholds developed severe ROP. Most of these infants who were not detected by the CO-ROP model had obvious deviation in expected weight trajectories or nonphysiologic weight gain. These findings suggest that the CO-ROP model needs to be revised before considering implementation into clinical practice.

Endothelial immune activation programmes cell-fate decisions and angiogenesis by inducing angiogenesis regulator DLL4 through TLR4-ERK-FOXC2 signalling

KEY POINTS

The mechanisms by which bacteria alter endothelial cell phenotypes and programme inflammatory angiogenesis remain unclear. In lung endothelial cells, we demonstrate that toll-like receptor 4 (TLR4) signalling induces activation of forkhead box protein C2 (FOXC2), a transcriptional factor implicated in lymphangiogenesis and endothelial specification, in an extracellular signal-regulated kinase (ERK)-dependent manner. TLR4-ERK-FOXC2 signalling regulates expression of the Notch ligand DLL4 and signals inflammatory angiogenesis in vivo and in vitro. Our work reveals a novel link between endothelial immune signalling (TLR pathway) and a vascular transcription factor, FOXC2, that regulates embryonic vascular development. This mechanism is likely to be relevant to pathological angiogenesis complicating inflammatory diseases in humans.

ABSTRACT

Endothelial cells (ECs) mediate a specific and robust immune response to bacteria in sepsis through the activation of toll-like receptor (TLR) signalling. The mechanisms by which bacterial ligands released during sepsis programme EC specification and altered angiogenesis remain unclear. We postulated that the forkhead box protein C2 (FOXC2) transcriptional factor directs EC cell-fate decisions and angiogenesis during TLR signalling. In human lung ECs, lipopolysaccharide (LPS) induced ERK phosphorylation, FOXC2, and delta-like 4 (DLL4, the master regulator of sprouting angiogenesis expression) in a TLR4-dependent manner. LPS-mediated ERK phosphorylation resulted in FOXC2-ERK protein ligation, ERK-dependent FOXC2 serine and threonine phosphorylation, and subsequent activation of DLL4 gene expression. Chemical inhibition of ERK or ERK-2 dominant negative transfection disrupted LPS-mediated FOXC2 phosphorylation and transcriptional activation of FOXC2. FOXC2-siRNA or ERK-inhibition attenuated LPS-induced DLL4 expression and angiogenic sprouting in vitro. In vivo, intraperitoneal LPS induced ERK and FOXC2 phosphorylation, FOXC2 binding to DLL4 promoter, and FOXC2/DLL4 expression in the lung. ERK-inhibition suppressed LPS-induced FOXC2 phosphorylation, FOXC2-DLL4 promoter binding, and induction of FOXC2 and DLL4 in mouse lung ECs. LPS induced aberrant retinal angiogenesis and DLL4 expression in neonatal mice, which was attenuated with ERK inhibition. FOXC2^+/- mice treated with LPS showed a mitigated increase in FOXC2 and DLL4 compared to FOXC2^+/+ mice. These data reveal a new mechanism (TLR4-ERK-FOXC2-DLL4) by which sepsis-induced EC TLR signalling programmes EC specification and altered angiogenesis.

Factors associated with retinopathy of prematurity ophthalmology workload

OBJECTIVE

This article reports on retinopathy of prematurity (ROP) workload in the NICU related to severity of disease, gestational age at discharge, and practice variation.

STUDY DESIGN

Data analysis on 1771 patients ≤ 30 weeks of gestation at birth from a de-identified data set of 13 NICUs.

RESULTS

There was a positive relationship between the severity of ROP and (1) the number of exams per patient, (2) the severity of ROP, and (3) postmenstrual age at discharge. The progression between the stages of ROP added to exam workload and postmenstrual age at NICU discharge. The addition of plus disease did not increase the exam burden. There was significant practice variation in the number of exams performed independent of ROP severity.

CONCLUSION

The progression of the severity of ROP independent of plus disease, and practice variations both contribute to ROP workload. Addressing these factors could decrease ROP workload without compromising American Academy of Pediatrics (AAP) guidelines.

N-terminal B-type natriuretic peptide urinary concentrations and retinopathy of prematurity

BackgroundTo validate the findings of a single-center pilot study showing elevated urinary N-terminal B-type natriuretic peptide (NTproBNP) concentrations in preterm infants subsequently developing severe retinopathy of prematurity (ROP) in a multicenter setting across eight European and Middle East countries.MethodsProspective observational study in 967 preterm infants <30 weeks' gestational age assessing the capacity of urinary NTproBNP on days of life (DOLs) 14 and 28 to predict ROP requiring treatment.ResultsUrinary NTproBNP concentrations were markedly elevated in infants who developed ROP requiring treatment (n=94) compared with survivors without ROP treatment (n=837), at both time points (median (interquartile range) DOL14: 8,950 (1,925-23,783) vs. 3,083 (1,193-17,393) vs. 816 (290-3,078) pg/ml, P<0.001) and DOL28 (2,203 (611-4,063) vs. 1,671 (254-11,340) vs. 408 (162-1,126) pg/ml, P<0.001). C-statistic of NTproBNP for treated ROP or death was 0.731 (95% confidence interval 0.654-0.774) for DOL14 and 0.683 (0.622-0.745) for DOL28 (P<0.001). Threshold scores were calculated, potentially enabling around 20% of infants with low NTproBNP scores never to be screened with ophthalmoscopy.ConclusionThere is a strong association between early urinary NTproBNP and subsequent ROP development, which can be used to further refine subgroups of patients with high or low risk of severe ROP.

Pathophysiology, screening and treatment of ROP: A multi-disciplinary perspective

The population of infants at risk for retinopathy of prematurity (ROP) varies by world region; in countries with well developed neonatal intensive care services, the highest risk infants are those born at less than 28 weeks gestational age (GA) and less than 1 kg at birth, while, in regions where many aspects of neonatal intensive and ophthalmological care are not routinely available, more mature infants up to 2000 g at birth and 37 weeks GA are also at risk for severe ROP. Treatment options for both groups of patients include standard retinal laser photocoagulation or, more recently, intravitreal anti-VEGF drugs. In addition to detection and treatment of ROP, this review highlights new opportunities created by telemedicine, where screening and diagnosis of ROP in remote locations can be undertaken by non-ophthalmologists using digital fundus cameras. The ophthalmological care of the ROP infant is undertaken in the wider context of neonatal care and general wellbeing of the infant. Because of this context, this review takes a multi-disciplinary perspective with contributions from retinal vascular biologists, pediatric ophthalmologists, an epidemiologist and a neonatologist. This review highlights the latest insights regarding cellular and molecular mechanisms in the formation of the retinal vasculature in the human infant, pathogenesis of ROP, detection and treatment of severe ROP, the risks and benefits of anti-VEGF therapy, the identification of new therapies over the horizon, and the optimal neonatal care regimen for best ROP outcomes, and the benefits and pitfalls of telemedicine in the remote screening and diagnosis of ROP, all of which have the potential to improve ROP outcomes.

An international comparison of retinopathy of prematurity grading performance within the Benefits of Oxygen Saturation Targeting II trials

Purpose

To investigate whether the observed international differences in retinopathy of prematurity (ROP) treatment rates within the Benefits of Oxygen Saturation Targeting (BOOST) II trials might have been caused by international variation in ROP disease grading.

Methods

Groups of BOOST II trial ophthalmologists in UK, Australia, and New Zealand (ANZ), and an international reference group (INT) used a web based system to grade a selection of RetCam images of ROP acquired during the BOOST II UK trial. Rates of decisions to treat, plus disease grading, ROP stage grading, ROP zone grading, inter-observer variation within groups and intra-observer variation within groups were measured.

Results

Forty-two eye examinations were graded. UK ophthalmologists diagnosed treat-requiring ROP more frequently than ANZ ophthalmologists, 13.9 (3.49) compared to 9.4 (4.46) eye examinations, P=0.038. UK ophthalmologists diagnosed plus disease more frequently than ANZ ophthalmologists, 14.1 (6.23) compared to 8.5 (3.24) eye examinations, P=0.021. ANZ ophthalmologists diagnosed stage 2 ROP more frequently than UK ophthalmologists, 20.2 (5.8) compared to 12.7 (7.1) eye examinations, P=0.026. There were no other significant differences in the grading of ROP stage or zone. Inter-observer variation was higher within the UK group than within the ANZ group. Intra-observer variation was low in both groups.

Conclusions

We have found evidence of international variation in the diagnosis of treatment-requiring ROP. Improved standardisation of the diagnosis of treatment-requiring ROP is required. Measures might include improved training in the grading of ROP, using an international approach, and further development of ROP image analysis software.

International variations and trends in the treatment for retinopathy of prematurity

OBJECTIVE

To compare the rates of retinopathy of prematurity (ROP) and treatment of ROP by laser or intravitreal anti-vascular endothelial growth factor among preterm neonates from high-income countries participating in the International Network for Evaluating Outcomes (iNeo) of neonates.

METHODS

A retrospective cohort study was conducted on extremely preterm infants weighing <1500 g at 24⁰ to 27⁶ weeks' gestation who were admitted to neonatal units in Australia/New Zealand, Canada, Finland, Israel, Japan, Spain, Sweden, Switzerland, Tuscany (Italy) and the UK between 2007 and 2013. Pairwise comparisons of ROP treatment in survivors between countries were evaluated by Poisson and multivariable logistic regression analyses after adjustment for confounders. A composite outcome of death or ROP treatment was compared between countries using logistic regression and standardised ratios.

RESULTS

Of 48 087 infants included in the analysis, 81.8% survived to 32 weeks postmenstrual age, and 95% of survivors were screened for ROP. Rates of any ROP ranged from 25.2% to 91.0% in Switzerland and Japan, respectively, among those examined. The overall rate of those receiving treatment was 24.9%, which varied from 4.3% to 30.4%. Adjusted risk ratios for ROP treatment were lower for Switzerland in all pairwise comparisons, whereas Japan displayed significantly higher ratios. Comparisons of the composite outcome between countries revealed similar, but less marked differences.

CONCLUSIONS

Rates of any ROP and ROP treatment varied significantly between iNeo members, while an overall decline in ROP treatment was observed during the study period. It is unclear whether these variations represent differences in care practices, diagnosis and/or treatment thresholds.

Characteristics of Severe Retinopathy of Prematurity in Infants with Birth Weight above 1500 Grams at a Referral Center in Turkey

PURPOSE

To demonstrate the clinical characteristics and treatment outcomes of severe retinopathy of prematurity (ROP) in preterm infants with birth weight (BW) above 1500 g in Turkey.

METHODS

A retrospective review of 5920 ROP records was performed in Zeynep Kamil Maternity and Children's Diseases Training and Research Hospital. The records were obtained from ROP treatment center of the same institute between 2011 and 2016. The data comprised the demographic and clinical characteristics including, gestational age, BW, systemic risk factors, zone and stage of ROP, ROP type, treatment modality, treatment outcomes and inborn/outborn status of the babies.

RESULTS

A total of 36 infants (71 eyes) with severe ROP and BW> 1500 g were retrieved. There were 30 infants (83.3%) with type 1 ROP and 6 infants (16.7%) with aggressive posterior ROP (APROP). 3 infants (8.3%) were born at our hospital whereas 33 (91.7%) were referred from outer private neonatal intensive care unit (NICU) centers. Zone I APROP was detected during the initial screening. 21 infants (58.3%) underwent laser treatment while 15 (41.7%) received intravitreal bevacizumab (IVB) injections. No unfavorable structural outcome was observed following either treatment modality.

CONCLUSION

Severe ROP may occur in heavier preterm infants. Laser treatment and IVB injections were useful in selected cases. Presence of APROP at first examination suggests an earlier screening in heavier babies. Standardization of private NICU centers as well as establishing a national ROP protocol is necessary in Turkey.