Retinopathy of prematurity: A comprehensive risk analysis for prevention and prediction of disease

Histological Chorioamnionitis and Funisitis as New Risk Factors for Retinopathy of Prematurity: A Meta-analysis

OBJECTIVE

 The role of placental inflammation in neonatal morbidities is underestimated due to lack of placental examination. This meta-analysis aims to assess the association between histological chorioamnionitis (HCA) with and without funisitis (FUN) and risk of retinopathy of prematurity (ROP).

STUDY DESIGN

 Forty-five studies reporting (unadjusted) data on HCA without FUN and HCA with FUN in neonates with ROP were included. Primary outcomes were any stage ROP and severe ROP. Potential confounders explored were gestational age (GA) at birth, birthweight, maternal steroid use, necrotizing enterocolitis, sepsis (suspected/proven) and mechanical ventilation duration.

RESULTS

 Neonates with HCA had increased risk for any stage ROP (odds ratio [OR] 1.8; 95% confidence interval [CI] 1.3-2.4) and severe ROP (OR 1.5; 95% CI 1.2-1.8) compared with neonates without HCA. The rates of any stage ROP (OR 1.8; 95% CI 1.4-2.2) and severe ROP (OR 1.4; 95% CI 1.1-1.6) were higher in neonates with FUN compared with neonates without FUN. Multivariate meta-regression analysis suggests that lower GA increases the effect size between FUN and severe ROP.

CONCLUSION

 This meta-analysis confirms that presence of HCA and FUN are risk factors for any stage ROP and severe ROP. Structured histological placental examination of HCA and FUN may be a tool to further refine the ROP risk profile.

KEY POINTS

· This systematic review confirms that HCA is a risk factor for ROP.. · This meta-analysis reveals that FUN results in an even higher risk for developing ROP.. · Placental examination of HCA/FUN may be a tool to further refine the ROP risk profile..

Comparison of Glutathione Nanoparticles, CoEnzyme Q10, and Fish Oil for Prevention of Oxygen-Induced Retinopathy in Neonatal Rats

Notch ligands and receptors are important for cell specification and angiogenesis, but their role in oxygen-induced retinopathy (OIR) is not well studied. Delta-like ligand (DLL)-4/Notch inhibits angiogenesis, while Jagged-1/Notch promotes angiogenesis. We tested the hypothesis that early supplementation with antioxidants and/or fish oil curtails severe OIR by inducing DLL-4/Notch and reducing Jagged-1/Notch. Newborn rats were exposed to brief intermittent hypoxia (IH) during hyperoxia, during which they received daily oral supplements of (1) fish oil, (2) coenzyme Q10 (CoQ10) in olive oil (OO), (3) glutathione nanoparticles (nGSH), (4) fish oil + CoQ10, or (5) OO (controls) from birth (P0) to P14. At P14, the pups were placed in room air (RA) until P21, with no further treatment. Oxidative stress, apoptosis, ocular histopathology, and Notch signaling were assessed. Neonatal IH resulted in severe retinal damage consistent with retinopathy of prematurity (ROP). Retinal damage was associated with induced oxidative stress and Jagged-1/Notch signaling, as well as reduced DLL-4/Notch signaling. All treatments reversed these outcomes, but nGSH produced the most beneficial outcomes. Severe OIR promoted the induction of Jagged-1/Notch and curtailed DLL-4/Notch, which was an effect that could be reversed with nGSH supplementation. These findings may indicate a potential alternate pathway for ROP treatment and/or prevention.

Comparative analysis of risk factors for retinopathy of prematurity in single and multiple birth neonates

AIM

To conduct a comparative analysis of risk factors for retinopathy of prematurity (ROP) in single- and multiple-born neonates.

METHODS

In a retrospective evaluation of 521 premature neonates, encompassing singletons, twins, and triplets born at or before 34 weeks of gestational age with a birthweight of less than 2000 g and who completed the ROP screening program, between 2020 and 2023, in outpatient referral ROP screening clinic affiliated by Shiraz University of Medical Sciences, were included. Neonates with the eligibility criteria were enrolled in the screening program from 28 days old age and followed up to discharge or treatment based on national ROP screening guideline. Data on ROP severity, outcome, treatment modality, and risk factors, including gestational age (GA), birth weight (BW), sex, duration of neonatal intensive care unit (NICU) admission, oxygen supplementation, mechanical ventilation, blood transfusion, method of delivery, and maternal and neonatal comorbidities, were extracted and compared between premature neonates from singleton and multiple births.

RESULTS

The analysis of the ROP severity distribution revealed 238 neonates (45.7%) with low-risk (type 2 prethreshold ROP or less severe) ROP and 16 (3.1%) with high-risk (type I prethreshold ROP or more severe) ROP who underwent treatment. According to the comparative analysis of risk factors in neonates with ROP requiring treatment, multiple birth neonates exhibited significantly greater GA (27.50 ± 3.27 vs. 30.00 ± 2.00 vs. 31.14 ± 0.38 weeks, p = 0.032 for singletons, twins and triplets, respectively); greater BW (861.67 ± 274.62 vs. 1233.33 ± 347.75 vs. 1537.14 ± 208.86 g, p = 0.002); and shorter duration of NICU admission (60.17 ± 21.36 vs. 34.00 ± 12.17 vs. 12.00 ± 6.32 days, p = 0.001) and oxygen supplementation (47.33 ± 16.57 vs. 36.00 ± 8.49 vs. 4.60 ± 2.41 days, p = 0.001). There was no significant difference between single-born neonates and multiple-born neonates regarding the prevalence of other risk factors. Multiple-born neonates with no ROP and low risk ROP showed significantly lower GA and BW compared to singletons (p < 0.001).

CONCLUSION

Multiple gestation neonates may develop high-risk ROP requiring treatment at a greater gestational age and birth weight and at a lower duration of oxygen supplementation and NICU admission compared to the single birth neonates. This pattern prompts a reevaluation of screening criteria, suggesting a potential need to consider multiple birth neonates with lower traditional risk factors in screening programs. This pattern should be further evaluated in larger populations of multiple born premature neonates.

Genome-wide association identifies novel ROP risk loci in a multiethnic cohort

We conducted a genome-wide association study (GWAS) in a multiethnic cohort of 920 at-risk infants for retinopathy of prematurity (ROP), a major cause of childhood blindness, identifying 1 locus at genome-wide significance level (p < 5×10-8) and 9 with significance of p < 5×10-6 for ROP ≥ stage 3. The most significant locus, rs2058019, reached genome-wide significance within the full multiethnic cohort (p = 4.96×10-9); Hispanic and European Ancestry infants driving the association. The lead single nucleotide polymorphism (SNP) falls in an intronic region within the Glioma-associated oncogene family zinc finger 3 (GLI3) gene. Relevance for GLI3 and other top-associated genes to human ocular disease was substantiated through in-silico extension analyses, genetic risk score analysis and expression profiling in human donor eye tissues. Thus, we identify a novel locus at GLI3 with relevance to retinal biology, supporting genetic susceptibilities for ROP risk with possible variability by race and ethnicity.

Placental Inflammation Significantly Correlates with Reduced Risk for Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a blinding condition affecting preterm infants, is an interruption of retinal vascular maturation that is incomplete when born preterm. Although ROP demonstrates delayed onset following preterm birth, representing a window for therapeutic intervention, there are no curative or preventative measures available for this condition. The in utero environment, including placental function, is increasingly recognized for contributions to preterm infant disease risk. The current study identified a protective association between acute placental inflammation and preterm infant ROP development using logistic regression, with the most significant association found for infants without gestational exposure to maternal preeclampsia and those with earlier preterm birth. Expression analysis of proteins with described ROP risk associations demonstrated significantly decreased placental high temperature requirement A serine peptidase-1 (HTRA-1) and fatty acid binding protein 4 protein expression in infants with acute placental inflammation compared with those without. Within the postnatal peripheral circulation, HTRA-1 and vascular endothelial growth factor-A demonstrated inverse longitudinal trends for infants born in the presence of, compared with absence of, acute placental inflammation. An agnostic approach, including whole transcriptome and differential methylation placental analysis, further identify novel mediators and pathways that may underly protection. Taken together, these data build on emerging literature showing a protective association between acute placental inflammation and ROP development and identify novel mechanisms that may inform postnatal risk associations in preterm infants.

Increased Risk of Retinopathy of Prematurity in Donors with Twin-to-Twin Transfusion Syndrome: A Cohort Study

INTRODUCTION

The purpose of this study was to evaluate the within-pair difference in retinopathy of prematurity (ROP) between donors and recipients with twin-to-twin transfusion syndrome (TTTS) and to identify risk factors for ROP development.

METHODS

This retrospective cohort study included 147 TTTS twin pairs managed between 2002 and 2022 and eligible for ROP screening. Primary outcomes were any stage ROP and severe ROP. Secondary outcomes were hemoglobin at birth, red blood cell transfusions, mechanical ventilation days, postnatal steroids, and neonatal morbidity. Donor status was defined as having polyhydramnios pre-laser.

RESULTS

Rates of any stage ROP (23% vs. 14%) and severe ROP (8% vs. 3%) were significantly higher in donors compared to recipients. Donors received a higher number of blood transfusions (1 [±1.9] versus 0.7 [±1.5]). Five factors were univariately associated with any stage ROP: donor status (odds ratio [OR] 1.9; 95% CI 1.3-2.9), lower gestational age (GA) at birth (OR 1.7; 95% CI 1.4-2.1), small for GA (OR 2.1; 95% CI 1.3-3.5), mechanical ventilation days (OR 1.1; 95% CI 1.1-1.2), and blood transfusions in phase 1 (OR 2.3; 95% CI 1.2-4.3). Three factors were independently associated with any stage ROP: donor status (OR 1.8; 95% CI 1.1-2.9), lower GA at birth (OR 1.6; 95% CI 1.2-2.1), and mechanical ventilation days (OR 1.1, 95% CI 1.0-1.1). Donor status was univariately associated with severe ROP (OR 2.3, 95% CI 1.1-5.0).

CONCLUSION

Any stage ROP and severe ROP are detected twice as frequently in donors compared to recipients. Increased awareness for ROP is needed in donors, especially those with lower GA at birth and longer duration of mechanical ventilation.

The relationship between probiotics and retinopathy of prematurity in preterm infants: A population-based retrospective study in China

Background

Retinopathy of prematurity (ROP) is a retinal vascular disease with a high incidence in premature infants and is a leading cause of childhood blindness worldwide. The purpose of our study was to analyze the association between the use of probiotics and retinopathy of prematurity.

Methods

This study retrospectively collected clinical data of premature infants with gestational age <32 weeks and birth weight <1500 g admitted to the neonatal intensive care unit from January 1, 2019 to December 31, 2021 in Suzhou Municipal Hospital, China. Demographic and clinical data of the inclusion population were collected. The outcome was the occurrence of ROP. The chi-square test was used to compare categorical variables, while the t-test and the nonparametric Mann-Whitney U rank-sum test were used for continuous variables. Univariate and multivariate logistic regression were used to analyze the relationship between probiotics and ROP.

Results

A total of 443 preterm infants met the inclusion criteria, of which 264 didn't receive probiotics and 179 were supplemented with probiotics. There were 121 newborns with ROP in the included population. The results of univariate analysis showed that the preterm infants with and without probiotics were significantly different in the gestational age, the birth weight, the one-minute Apgar score, the oxygen inhalation time, the acceptance rate of invasive mechanical ventilation, the prevalence of bronchopulmonary dysplasia, ROP and severe intraventricular hemorrhage and periventricular leukomalacia (P < 0.05). Unadjusted univariate logistic regression model result showed that probiotics (OR 0.383, 95% CI 0.240∼0.611) were the factors affecting ROP in preterm infants (P < 0.01). Multivariate logistic regression result (OR 0.575, 95% CI 0.333∼0.994) was consistent with univariate analysis (P < 0.05).

Conclusion

This study showed that probiotic was associated with a reduced risk of ROP in preterm infants with gestational age of <32 weeks and birth weight of <1500 g, but more large-scale prospective studies are still needed.

Predicting clinical outcomes using artificial intelligence and machine learning in neonatal intensive care units: a systematic review

BACKGROUND

Advances in technology, data availability, and analytics have helped improve quality of care in the neonatal intensive care unit.

OBJECTIVE

To provide an in-depth review of artificial intelligence (AI) and machine learning techniques being utilized to predict neonatal outcomes.

METHODS

The PRISMA protocol was followed that considered articles from established digital repositories. Included articles were categorized based on predictions of: (a) major neonatal morbidities such as sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and retinopathy of prematurity; (b) mortality; and (c) length of stay.

RESULTS

A total of 366 studies were considered; 68 studies were eligible for inclusion in the review. The current set of predictor models are primarily built on supervised learning and mostly used regression models built on retrospective data.

CONCLUSION

With the availability of EMR data and data-sharing of NICU outcomes across neonatal research networks, machine learning algorithms have shown breakthrough performance in predicting neonatal disease.

Quantification of Early Neonatal Oxygen Exposure as a Risk Factor for Retinopathy of Prematurity Requiring Treatment

Purpose

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness related to oxygen exposure in premature infants. Since oxygen monitoring protocols have reduced the incidence of treatment-requiring ROP (TR-ROP), it remains unclear whether oxygen exposure remains a relevant risk factor for incident TR-ROP and aggressive ROP (A-ROP), a severe, rapidly progressing form of ROP. The purpose of this proof-of-concept study was to use electronic health record (EHR) data to evaluate early oxygen exposure as a predictive variable for developing TR-ROP and A-ROP.

Design

Retrospective cohort study.

Participants

Two hundred forty-four infants screened for ROP at a single academic center.

Methods

For each infant, oxygen saturations and fraction of inspired oxygen (FiO₂) were extracted manually from the EHR until 31 weeks postmenstrual age (PMA). Cumulative minimum, maximum, and mean oxygen saturation and FiO₂ were calculated on a weekly basis. Random forest models were trained with 5-fold cross-validation using gestational age (GA) and cumulative minimum FiO₂ at 30 weeks PMA to identify infants who developed TR-ROP. Secondary receiver operating characteristic (ROC) curve analysis of infants with or without A-ROP was performed without cross-validation because of small numbers.

Main Outcome Measures

For each model, cross-validation performance for incident TR-ROP was assessed using area under the ROC curve (AUC) and area under the precision-recall curve (AUPRC) scores. For A-ROP, we calculated AUC and evaluated sensitivity and specificity at a high-sensitivity operating point.

Results

Of the 244 infants included, 33 developed TR-ROP, of which 5 developed A-ROP. For incident TR-ROP, random forest models trained on GA plus cumulative minimum FiO₂ (AUC = 0.93 ± 0.06; AUPRC = 0.76 ± 0.08) were not significantly better than models trained on GA alone (AUC = 0.92 ± 0.06 [P = 0.59]; AUPRC = 0.74 ± 0.12 [P = 0.32]). Models using oxygen alone showed an AUC of 0.80 ± 0.09. ROC analysis for A-ROP found an AUC of 0.92 (95% confidence interval, 0.87–0.96).

Conclusions

Oxygen exposure can be extracted from the EHR and quantified as a risk factor for incident TR-ROP and A-ROP. Extracting quantifiable clinical features from the EHR may be useful for building risk models for multiple diseases and evaluating the complex relationships among oxygen exposure, ROP, and other sequelae of prematurity.

Retinopathy prematurity: a systematic review and meta-analysis study based on neonatal and maternal risk factors

BACKGROUND

Retinopathy of prematurity is the abnormal development of retinal arteries in preterm neonates less than 32 weeks and weighing 1500 g, and less, which can lead to visual impairment during life and blindness. This study aims to investigate the relationship between some clinical characteristics of neonates and mothers with Retinopathy of prematurity in the world via a systematic review and meta-analysis.

MATERIALS AND METHODS

The present study is a systematic review and meta-analysis on the relationship between maternal and neonatal clinical variables with Retinopathy of prematurity in the world from the beginning of 2000 to the end of 2020. Accordingly, all English articles published on the topic were searched in scientific databases of Web of Science, PubMed, Google Scholar, Science Direct, and Scopus. The articles were searched independently by two researchers. Statistical analysis of data was performed using fixed and random effects model statistical tests in the meta-analysis, Cochran, meta-regression, I² index, Funnel plot, and Begg's by STATA software program, version 14.

RESULT

A total of 191 studies with a sample size of 140,921 persons were including in the meta-analysis. Accordingly, Preterm delivery ≤28 weeks (OR:6.3, 95% CI:4.9-8.1), Birth Weight ≤1000 g (OR:5.8, 95% CI:4.8-6.8), Birth Weight ≤1500 g (OR:4.8, 95% CI:3.8-6.1), PROM (OR:1.2, 95% CI:1.0-1.4), induced fertility (OR:1.9, 95% CI:1.1-3.0) and Chorioamnionitis (OR:1.5, 95% CI:1.0-2.2) There was a statistically significant association with retinopathy.

CONCLUSION

Based on the results of the present meta-analysis, the risk of retinopathy of prematurity in neonates born at 28 weeks and less, LBW (weight 1500 g and less), neonatal hypotension, chorioamnionitis, and induced fertility increases.

Proportion of Retinopathy of Prematurity That Was Treated across Regions in the United States

OBJECTIVES

Retinopathy of prematurity (ROP) is the leading preventable cause of blindness in children worldwide. Major eye and visual problems are strongly linked to ROP requiring treatment. Objectives of the study are to: (1) evaluate the trends and regional differences in the proportion of treated ROP, (2) describe risk factors, and (3) examine if treated ROP predicts mortality.

STUDY DESIGN

Retrospective data analysis was conducted using the Kids' Inpatient Database from 1997 to 2012. ROP was categorized into treated ROP (requiring laser photocoagulation or surgical intervention) and nontreated ROP. Bivariate and multivariate logistic regression analyses were performed.

RESULTS

Out of 21,955,949 infants ≤ 12 months old, we identified 70,541 cases of ROP and 7,167 (10.2%) were treated. Over time, the proportion of treated ROP decreased (p = < 0.001). While extremely low birth weight infants cared for in the Midwest was associated with treated ROP (adjusted odds ratio [aOR] = 29.05; 95% confidence interval [CI]: 10.64-79.34), black race (aOR = 0.57; 95% CI: 0.51-0.64) care for in the birth hospital (aOR = 0.44; 95% CI: 0.41-0.48) was protective. Treated ROP was not associated with mortality.

CONCLUSION

The proportion of ROP that is surgically treated has decreased in the United States; however, there is variability among the different regions. Demographics and clinical practice may have contributed for this variability.

Risk factors for the development and progression of retinopathy of prematurity in preterm infants in Indonesia

BACKGROUND

Risk factors other than supplemental oxygen might play a role in the development of retinopathy of prematurity (ROP). In Indonesia ROP occurs in infants up to 34 weeks and 2000 g. Risk factors for the development of ROP in Indonesian NICUs have not been evaluated. Our aim was to identify other risk factors than the use of oxygen in the development and progression of ROP in preterm infants in Indonesia.

METHODOLOGY

Data on 98 preterm infants with ROP and 77 controls were collected from four NICUs and two eye centers in Jakarta, Indonesia, between 2009 and 2014. We used multivariate logistic regression analysis to determine the relationship between infants and environmental variables and the development and progression of ROP. We obtained variables for ROP severity by using Cox regression analysis.

RESULTS

Factors associated with the development of ROP were birthweight (BWt), intrauterine growth retardation (IUGR), exchange transfusion, duration of oxygen supplementation, minimum saturation monitor setting, and socioeconomic factors. Regarding the progression, gestational age (GA), out-born, duration of supplemental oxygen, minimum saturation monitor setting, and socioeconomic factors were identified as risk factors.

CONCLUSION

The use and control of supplemental oxygen are the main risk factors for the development and progression of ROP in preterms in Indonesia. Additionally, we confirm that GA, BWt, and IUGR are risk factors. Moreover, we found exchange transfusion to be a risk factor, and we found a lower rate of ROP in infants from a lower socioeconomic background. These risk factors apply to infants with a GA up to 34 weeks and a BWt up to 2000 g.

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.

The Serine Protease HTRA-1 Is a Biomarker for ROP and Mediates Retinal Neovascularization

Retinopathy of prematurity (ROP) is a blinding aberrancy of retinal vascular maturation in preterm infants. Despite delayed onset after preterm birth, representing a window for therapeutic intervention, we cannot prevent or cure ROP blindness. A natural form of ROP protection exists in the setting of early-onset maternal preeclampsia, though is not well characterized. As ischemia is a central feature in both ROP and preeclampsia, we hypothesized that angiogenesis mediators may underlie this protection. To test our hypothesis we analyzed peripheral blood expression of candidate proteins with suggested roles in preeclamptic and ROP pathophysiology and with a proposed angiogenesis function (HTRA-1, IGF-1, TGFβ-1, and VEGF-A). Analysis in a discovery cohort of 40 maternal-infant pairs found that elevated HTRA-1 (high-temperature requirement-A serine peptidase-1) was significantly associated with increased risk of ROP and the absence of preeclampsia, thus fitting a model of preeclampsia-mediated ROP protection. We validated these findings and further demonstrated a dose-response between systemic infant HTRA-1 expression and risk for ROP development in a larger and more diverse validation cohort consisting of preterm infants recruited from two institutions. Functional analysis in the oxygen-induced retinopathy (OIR) murine model of ROP supported our systemic human findings at the local tissue level, demonstrating that HtrA-1 expression is elevated in both the neurosensory retina and retinal pigment epithelium by RT-PCR in the ROP disease state. Finally, transgenic mice over-expressing HtrA-1 demonstrate greater ROP disease severity in this model. Thus, HTRA-1 may underlie ROP protection in preeclampsia and represent an avenue for disease prevention, which does not currently exist.

Trends in Retinopathy of Prematurity over 12 Years in a Colorado Cohort

PURPOSE

To determine trends in retinopathy of prematurity (ROP) in a Colorado cohort between 2006 and 2017 and compare trends in risk factors between our cohort and statewide data.

METHODS

A retrospective cohort study was conducted by the use of records from two registry databases: 1) an academic center's ROP registry, and 2) vital statistics birth data from the Colorado Department of Public Health and Environment (CDPHE). ROP was categorized as severe (type 1 or type 2), low grade (not type 1 or type 2), or no ROP. Other variables included in the analyses were gestational age and birth weight at delivery, and infant mortality. Trends over time were evaluated for both registry databases using generalized linear models.

RESULTS

In our ROP registry cohort of 1,267 eligible infants, 134 (10.6%) developed severe ROP and 279 (22%) developed low-grade ROP. We found no overall trend in severe ROP rates (p = .23), and a decreasing trend in rates of low-grade ROP (p < .01) over the study period. Trends in gestational age, birth weight, and mortality rates remained stable during the study period in both the ROP registry and the CDPHE cohorts.

CONCLUSION

The rate of severe ROP in our ROP registry cohort did not change over time. There was evidence of a decreasing trend in low grade ROP during the 12-year study period that was not explained by a change in the primary ROP risk factors in either the ROP registry cohort or the Colorado statewide data.

Current evidence and outcomes for retinopathy of prematurity prevention: insight into novel maternal and placental contributions

Retinopathy of prematurity (ROP) is a blinding morbidity of preterm infants, which represents a significant clinical problem, accounting for up to 40% of all childhood blindness. ROP displays a range of severity, though even mild disease may result in life-long visual impairment. This is complicated by the fact that our current treatments have significant ocular and potentially systemic effects. Therefore, disease prevention is desperately needed to mitigate the life-long deleterious effects of ROP for preterm infants. Although ROP demonstrates a delayed onset of retinal disease following preterm birth, representing a potential window for prevention, we have been unable to sufficiently alter the natural disease course and meaningfully prevent ROP. Prevention therapeutics requires knowledge of early ROP molecular changes and risk, occurring prior to clinical retinal disease. While we still have an incomplete understanding of these disease mechanisms, emerging data integrating contributions of maternal/placental pathobiology with ROP are poised to inform novel approaches to prevention. Herein, we review the molecular basis for current prevention strategies and the clinical outcomes of these interventions. We also discuss how insights into early ROP pathophysiology may be gained by a better understanding of maternal and placental factors playing a role in preterm birth.

High-Dose Erythropoietin in Extremely Low Gestational Age Neonates Does Not Alter Risk of Retinopathy of Prematurity

INTRODUCTION

The Preterm Erythropoietin (Epo) Neuroprotection (PENUT) Trial sought to determine the safety and efficacy of early high-dose Epo as a potential neuroprotective treatment. We hypothesized that Epo would not increase the incidence or severity of retinopathy of prematurity (ROP).

METHODS

A total of 941 infants born between 24-0/7 and 27-6/7 weeks' gestation were randomized to 1,000 U/kg Epo or placebo intravenously for 6 doses, followed by subcutaneous or sham injections of 400 U/kg Epo 3 times a week through 32 weeks post-menstrual age. In this secondary analysis of PENUT trial data, survivors were evaluated for ROP. A modified intention-to-treat approach was used to compare treatment groups. In addition, risk factors for ROP were evaluated using regression methods that account for multiples and allow for adjustment for treatment and gestational age at birth.

RESULTS

Of 845 subjects who underwent ROP examination, 503 were diagnosed with ROP with similar incidence and severity between treatment groups. Gestational age at birth, birth weight, prenatal magnesium sulfate, maternal antibiotic exposure, and presence of heart murmur at 2 weeks predicted the development of any ROP, while being on high-frequency oscillator or high-frequency jet ventilation (HFOV/HFJV) at 2 weeks predicted severe ROP.

CONCLUSION

Early high-dose Epo followed by maintenance dosing through 32 weeks does not increase the risk of any or severe ROP in extremely low gestational age neonates. Gestational age, birth weight, maternal treatment with magnesium sulfate, antibiotic use during pregnancy, and presence of a heart murmur at 2 weeks were associated with increased risk of any ROP. Treatment with HFOV/HFJV was associated with an increased risk of severe ROP.

Refining evidence-based retinopathy of prematurity screening guidelines: The SCREENROP study

Purpose

Retinopathy of prematurity (ROP) is a potentially blinding condition affecting premature infants for which less than 10% of babies undergoing screening require treatment. This study assessed and validated predictors of developing clinically significant ROP (type 2 or worse) and ROP requiring treatment.

Design

Nationwide retrospective cohort study.

Methods

This study included infants born between January 2014 and June 2016, admitted to level 3 neonatal intensive care units across Canada who underwent ROP screening. Data were derived from the Canadian Neonatal Network database. Predefined ≥ 1% risk for clinically significant retinopathy or prematurity and ROP requiring treatment was set as threshold for screening. Thirty-two potential predictors were analyzed, to identify and validate the most important ones for predicting clinically significant ROP. The predictors were determined on a derivation cohort and tested on a validation cohort. Multivariable logistic regression modeling was used for analysis.

Results

Using a sample of 4,888 babies and analyzing 32 potential predictors, capturing babies with ≥1% risk of developing clinically significant ROP equated to screening babies with birth weight (BW) <1,300 g or gestational age (GA) <30 weeks while capturing babies with ≥1% risk of requiring ROP treatment equated to screening babies with BW <1,200 g or GA <29 weeks.

Conclusions

The Canadian ROP screening criteria can be modified to screen babies with BW <1,200 g or GA <30 weeks. Using these criteria, babies requiring treatment would be identified while reducing the number of babies screened unnecessarily.

Relationship between severe bronchopulmonary dysplasia and severe retinopathy of prematurity in premature newborns

BACKGROUND

Bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP) are two adverse sequelae of preterm birth associated with abnormal vascular development. The purpose of this study was to characterize the relationship between these two outcomes at a single institution.

METHODS

The medical records of infants screened for ROP at the University of Colorado Hospital between January 2012 and December 2017 were reviewed retrospectively. ROP was classified according to Early Treatment Retinopathy of Prematurity (ET-ROP) criteria; BPD, according to the 2010 Criteria from the National Institute for Child Health and Human Development. We examined the relationship between moderate-severe BPD and the development of severe ROP (type 1 or 2) using univariate analysis and multivariable logistic regression with the odds ratio as a measure of association. Covariates included gestational age and birth weight at delivery.

RESULTS

A total of 625 cases were reviewed. Of these, 64 infants (10%) developed severe ROP and 176 (28%) infants developed moderate-severe BPD. We found a significant relationship between these two outcomes following adjustments for gestational age, birth weight, and multiparity (OR = 3.2; 95% CI, 1.6-6.5 [P < 0.01]).

CONCLUSIONS

In our cohort of preterm infants, we found a significant relationship between moderate-severe BPD with severe ROP. We hypothesize that these two neonatal outcomes have links with a common pathogenesis.

Is human milk feeding protective for Retinopathy of Prematurity?

Objective:

To find the association between breast milk feeding with retinopathy of prematurity (ROP) in preterm infants.

Methods:

This was a cross sectional study to examine the effects of breast milk feeding on ROP. Premature newborns below 34 weeks from neonatal unit retinopathy of prematurity program during the years 2015 to 2017 of The Lahore General Hospital were included. We recorded the gestational age, birth weight, presence of ROP and the type of feeding (breastfeeding vs. formula milk).

Results:

Out of 428 preterm babies 210 (49%) were males. More babies were between 32-34 weeks of gestation 229 (53.5%) as compared to < 32 weeks 199 (46.5%). Among all 428 preterm infants 19(4.4%) developed ROP. Majority 13 (68.4%) who developed ROP were <32 weeks of gestation (p=0.042). The mean birth weight of infants without ROP was 1.51± 0.36 kg (95%CI; 1.47-1.55), while it was 1.36 ± 0.29 kg (95%CI; 1.22-1.50) with ROP and all who developed ROP were < 2kg. The estimated odds ratio of developing ROP for breast fed versus top feeding was (ORs: 0.571, 95% CI; 0.222- 1.489). There was a trend toward lower incidence of ROP in the group of newborns who received breast-feeding (36.8%) as compared to top feeding (63.2%) but almost similar percentage who didn’t develop ROP were breast fed or top fed with statistically insignificant results (p= 0.24).

Conclusions:

Slightly lesser percentage of preterm babies who were breast fed developed retinopathy of prematurity.

Incidence and risk factors for retinopathy of prematurity: a retrospective cohort study

BACKGROUND AND OBJECTIVES

Advances in neonatal care promoted increased survival rates of preterm infants, with a consequent increase in the number of children affected by retinopathy of prematurity (ROP). This study estimates the incidence of ROP and evaluates potential risk factors associated.

METHODS

A retrospective cohort study of preterm infants born in a tertiary neonatal intensive care unit was conducted from March 2005 to August 2015. Six hundred and thirty-nine newborns were included based on the following criteria: infants born with less than 32 weeks' gestation or birth weight below 1500 g; or neonates born with 32-37 weeks' gestation or birth weight above 1500 g and any of the following associated: multiple gestation, respiratory distress syndrome, sepsis, blood transfusions or intraventricular hemorrhage. Neonates were followed up until disease resolution or until treatment criteria was achieved.

RESULTS

A total of 602 newborns were evaluated after applying the exclusion criteria. Mean gestational age was 30.7 ± 2.5 weeks. The incidences of ROP at any stage and of type 1 prethreshold ROP were 33.9 and 5.0% respectively. Logistic regression analysis revealed that risk factors associated with ROP at any stage were extremely low birth weight (ELBW) (odds ratio [OR] = 3.10; 95% confidence interval [95% CI]:1.73-5.55), pulmonary diseases (OR = 2.49; 95% CI: 1.35-4.59), intraventricular hemorrhage (OR = 2.17; 95% CI: 1.10-4.30), and low gestational age (OR = 0.81; 95% CI: 0.73-0.91). The main risk factors associated with type 1 prethreshold ROP were pulmonary diseases (OR = 9.58; 95% CI: 1.27-72.04) and ELBW (OR = 3.66; 95% CI: 1.67-8.00).

CONCLUSION

This study found a significant incidence of ROP (33.9%) in the studied population, and highlighted pulmonary diseases as a significant risk factor for type 1 prethreshold ROP.

The role of the maternal and fetal inflammatory response in retinopathy of prematurity

PROBLEM

There is a paucity of research on the contribution of placental inflammation to severe retinopathy of prematurity (ROP).

METHOD OF STUDY

A retrospective cohort study (n = 1217) was conducted of infants screened for ROP (2006-2016). The outcomes of the study were severe ROP (type 1 or type 2 ROP) and low grade ROP. We categorized the placental pathology as the presence of (i) maternal plus fetal inflammatory response, (ii) maternal inflammatory response only, (iii) fetal inflammatory response only and, (iv) no evidence of a maternal or fetal inflammatory response. The data were analyzed using univariate and multivariate logistic regression analyses (P < .05).

RESULTS

In this cohort, the number of infants with the maternal plus fetal inflammatory response, the maternal inflammatory response only, the fetal inflammatory response only, and no maternal or fetal inflammatory response was 305 (25%), 82 (7%), 8 (1%), and 822 (67%), respectively. Adjusted for covariates, the maternal plus fetal inflammatory response was a significant risk factor for severe ROP (AOR = 2.6, 95% CI 1.1-5.9, P = .03). None of the categories of placental inflammation were significantly associated with low grade ROP.

CONCLUSION

Placental pathology distinguished by the maternal plus fetal inflammatory response was a significant risk factor for severe ROP. Our study supports a link between intrauterine inflammatory events and the subsequent development of severe ROP.

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.

Identifying Risk Factors Shared by Bronchopulmonary Dysplasia, Severe Retinopathy, and Cystic Periventricular Leukomalacia in Very Preterm Infants for Targeted Intervention

BACKGROUND

Bronchopulmonary dysplasia (BPD), severe retinopathy of prematurity (sROP), and cystic periventricular leukomalacia (cPVL) are 3 major morbidities with long-term neurodevelopmental impairments in preterm infants.

OBJECTIVE

To investigate the strength of associations and identify key risk factors shared by BPD, sROP, and cPVL for targeted intervention.

METHODS

We studied the Taiwanese very-preterm-infant registry data on 3,507 infants admitted to neonatal intensive care units and discharged at postmenstrual age ≥36 weeks between 2008 and 2013.

RESULTS

Of 3,507 infants, 1,497 presented with at least 1 morbidity (26 [1.7%], 386 [25.8%], and 1,085 [72.5%] exhibited 3, 2, and 1 morbidities, respectively). BPD was strongly associated with sROP (odds ratio 5.93; 95% confidence interval 5.02-7.03), followed by cPVL (2.08; 1.63-2.64), but sROP and cPVL were weakly associated (1.59; 1.17-2.13). Most risk factors contributed to BPD, which shared risk factors with sROP and cPVL. A birth weight of < 1,000 g, male sex, and prolonged mechanical ventilation (MV) were shared by BPD and sROP, and chorioamnionitis, severe respiratory distress syndrome, and prolonged MV specifically contributed to BPD and cPVL. Prolonged MV was the single risk factor common to BPD, sROP, and cPVL. Avoiding prolonged MV reduced the risk of having at least 1 of the 3 morbidities by 37%.

CONCLUSIONS

BPD and sROP were most strongly associated. Most risk factors contributed to BPD, with differentially shared effects on sROP and cPVL. Prolonged MV was the only risk factor shared by all 3 morbidities, and avoiding it potentially reduced the risk of having at least 1 of them.