Longitudinal analysis of carotenoid content in preterm human milk.

To describe the variability in carotenoid content of human milk (HM) in mothers of very to extremely low birth weight preterm infants throughout lactation and to explore the relationship between lutein in HM and the occurrence of retinopathy of prematurity (ROP) in preterm infants. We recruited healthy mothers along with their preterm infants that were born at gestational age 24 + 2 to 29 + 6 weeks or with a birth weight under 1500 g and were exclusively breastfed HM. Each participant provided up to 7 HM samples (2-10 ml) on day 0-3 and once a week until 6 weeks. Additionally, when possible, a blood sample was collected from the infant at week 6. Concentrations of the major carotenoids (lutein, zeaxanthin, beta-carotene, and lycopene) in all HM and blood samples were assessed and compared. Thirty-nine mother-infant dyads were included and 184 HM samples and 21 plasma samples were provided. Mean lutein, zeaxanthin, beta-carotene, and lycopene concentration decreased as lactation progressed, being at their highest in colostrum samples (156.9 vs. 66.9 vs. 363.9 vs. 426.8 ng/ml, respectively). Lycopene (41%) and beta-carotene (36%) were the predominant carotenoids in colostrum and up to 2 weeks post-delivery. Inversely, the proportion of lutein and zeaxanthin increased with lactation duration to account for 45% of the carotenoids in mature HM. Lutein accounted for 58% of the carotenoids in infant plasma and only 28% in HM. Lutein content of transition and mature HM did not differ between mothers of ROP and non-ROP infants.Conclusion Carotenoid content of HM was dynamic and varied between mothers and as lactation progressed. Infant plasma displayed a distinct distribution of carotenoids from HM.

Comparative Analysis Reveals Novel Changes in Plasma Metabolites and Metabolomic Networks of Infants With Retinopathy of Prematurity.

Purpose: Advances in mass spectrometry have provided new insights into the role of metabolomics in the etiology of several diseases. Studies on retinopathy of prematurity (ROP), for example, overlooked the role of metabolic alterations in disease development. We employed comprehensive metabolic profiling and gold-standard metabolic analysis to explore major metabolites and metabolic pathways, which were significantly affected in early stages of pathogenesis toward ROP. Methods: This was a multicenter, retrospective, matched-pair, case-control study. We collected plasma from 57 ROP cases and 57 strictly matched non-ROP controls. Non-targeted ultra-high-performance liquid chromatography-tandem mass spectroscopy (UPLC-MS/MS) was used to detect the metabolites. Machine learning was employed to reveal the most affected metabolites and pathways in ROP development. Results: Compared with non-ROP controls, we found a significant metabolic perturbation in the plasma of ROP cases, which featured an increase in the levels of lipids, nucleotides, and carbohydrate metabolites and lower levels of peptides. Machine leaning enabled us to distinguish a cluster of metabolic pathways (glycometabolism, redox homeostasis, lipid metabolism, and arginine pathway) were strongly correlated with the development of ROP. Moreover, the severity of ROP was associated with the levels of creatinine and ribitol; also, overactivity of aerobic glycolysis and lipid metabolism was noted in the metabolic profile of ROP. Conclusions: The results suggest a strong correlation between metabolic profiling and retinal neovascularization in ROP pathogenesis. These findings provide an insight into the identification of novel metabolic biomarkers for the diagnosis and prevention of ROP, but the clinical significance requires further validation.

Correlation between hyperglycemia and glycated albumin with retinopathy of prematurity.

To determine the association between hyperglycemia, glycated albumin (GlyA) and retinopathy of prematurity (ROP). Prospective study of all infants under ROP screening from March 2017 to July 2019. All demographic, clinical and laboratory data were collected. Glucose was measured at birth and every 8 h for the first week and serum GlyA was evaluated at birth, 1st, 2nd and 4th weeks after birth. Reference range for GlyA was obtained. Univariate logistic regression was used to examine risk factors for ROP followed by multivariate regression. A total of 152 infants were included in the study. Median gestational age was 30 weeks and median birth weight 1240 g. Thirty-three infants (21.7%) had ROP. Hyperglycemia was present in 24 (72.7%) infants diagnosed with any ROP versus 6 (0.05%) in those without ROP. Median GlyA at birth, 1st, 2nd and 4th and respective reference ranges were 8.50% (6.00-12.65), 8.20% (5.32-11.67), 8.00% (5.32-10.00) and 7.90% (5.30-9.00) respectively. After multivariate logistic regression, hyperglycemia but not GlyA, remained a significant risk factor for ROP overpowering the other recognized risk factors (Exp (B) 28.062, 95% CI for Exp(B) 7.881-99.924 p < 0.001). In our cohort, hyperglycemia but not GlyA, remained a significant risk factor for ROP overpowering the other recognized risk factors.

Plasma levels of amino acids and derivatives in retinopathy of prematurity.

Background: Retinopathy of prematurity (ROP) is a retinal disease that causes blindness in premature infants. This study aimed to reveal the changes in amino acids and derivatives in the plasma of ROP patients compared with premature infants without ROP. Methods: Metabolomics targeting amino acids and their derivatives was conducted to assess their plasma levels in ROP patients (n=58) and premature infants without ROP (n=25), and KEGG pathway analysis was used to identify the involved pathways. Results: Among the 31 assessed metabolites, the levels of 4 amino acids were significantly altered in the ROP group. Creatinine was downregulated in the plasma of the ROP patients, while the levels of citrulline, arginine, and aminoadipic acid were upregulated in the ROP group. Significant correlations were identified between the ROP stage and plasma levels of citrulline, creatinine, and aminoadipic acid. The involved pathways included biosynthesis of amino acids, arginine and proline metabolism, and arginine biosynthesis. Conclusion: The plasma levels of citrulline, creatinine, arginine, and aminoadipic acid were significantly changed in ROP patients. These metabolites could be considered potential biomarkers of ROP, and their related metabolic pathways might be involved in ROP pathogenesis.

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

Importance: Circulating levels of neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) are important in the course of brain injury in adults, but longitudinal postnatal circulating levels in preterm infants have not been investigated. Objectives: To examine postnatal longitudinal serum levels of NfL and GFAP in preterm infants during the first 15 weeks of life and to explore possible associations between these biomarkers, neonatal morbidities, and neurodevelopmental outcomes at 2 years. Design, Setting, and Participants: This cohort study used data from 3 clinical studies, including 221 infants born before 32 weeks gestational age (GA) from 1999 to 2015; neurodevelopmental outcomes were evaluated in 120 infants. Data were collected at tertiary-level neonatal intensive care units in Gothenburg, Lund, and Uppsala, Sweden. Data analysis was conducted from January to October 2020. Exposure: Preterm birth. Main Outcomes and Measures: Serum NfL and GFAP levels, retinopathy of prematurity (ROP), intraventricular hemorrhage, and Bayley Scales of Infant Development II and III at 2 years of age, analyzed by multivariate logistic regression measured by odds ratio (OR), and receiver operating characteristic curve (ROC) analysis. Area under the curve (AUC) was also measured. Results: The 221 included infants (108 [48.9%] girls) had a mean (SD) GA at birth of 26.5 (2.1) weeks and a mean (SD) birth weight of 896 (301) grams. NfL levels increased after birth, remaining high during the first 4 weeks of life before declining to continuously low levels by postnatal age 12 weeks (median [range] NfL level at birth: 58.8 [11.5-1371.3] ng/L; 1 wk: 83.5 [14.1-952.2] ng/L; 4 wk: 24.4 [7.0-306.0] ng/L; 12 wk: 9.1 [3.7-57.0] ng/L). In a binary logistic regression model adjusted for GA at birth, birth weight SD score, Apgar status at 5 minutes, and mode of delivery, the NfL AUC at weeks 2 to 4 was independently associated with any ROP (OR, 4.79; 95% CI, 2.17-10.56; P < .001). In an exploratory analysis adjusted for GA at birth and sex, NfL AUC at weeks 2 to 4 was independently associated with unfavorable neurodevelopmental outcomes at 2 years corrected age (OR per 10-unit NfL increase, 1.07; 95% CI, 1.02-1.13; P = .01). Longitudinal GFAP levels were not significantly associated with neonatal morbidity or neurodevelopmental outcome. Conclusions and Relevance: In this study, high NfL levels during the first weeks of life were associated with ROP and poor neurodevelopmental outcomes at 2 years of age. Associations between NfL and later neurovascular development in infants born prematurely should be investigated further.

Umbilical Blood Levels of IL-6 and TNF-α as Predictors of the Central Nervous System Damage and Retinopathy in Preterm Infants.

OBJECTIVE: The aim was to identify the critical levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor-A in umbilical cord blood that could be used as markers for predicting the central nervous system (CNS) damage and retinopathy of prematurity (ROP) in preterm infants. STUDY DESIGN: A total of 158 preterm infants, born at 22 to 34 weeks of gestation, were evaluated in the first week after birth and at 36 to 37 weeks of postconceptual age. RESULTS: A significant relationship between CNS changes and concentrations of IL-6 (p < 0.001) and TNF-α (p < 0.001) in umbilical cord blood at 22 to 34 weeks of gestation was determined. The concentration of IL-6 >13.0 pg/mL predicts significant CNS damages in 36 to 37-week infants (p = 0.013). ROP was diagnosed in 24.8% infants (n = 149). It was detected that the levels of TNF-α >116.4 pg/mL (p < 0.001) and IL-6 >13.0 pg/mL (p < 0.05) in umbilical cord blood could predict 2 to 3/3 to 4 stages of ROP. CONCLUSION: Critical values of IL-6 and TNF-α in predicting ≥grade III intraventricular hemorrhage in the early adaptation and in predicting marked CNS damages and severe ROP stages in the later adaptation of preterm infants were determined.

Plasma metabolites in treatment-requiring retinopathy of prematurity: Potential biomarkers identified by metabolomics.

Retinopathy of prematurity (ROP) is a potentially blinding condition caused by disruption of retinal vascularization and metabolism. This study aims to identify altered metabolites from plasma in patients with treatment-requiring ROP (TR-ROP) compared with controls. An untargeted metabolomics analysis was performed to reveal the metabolomic profiles of the plasma between TR-ROP patients (n = 38) and age-matched infants (n = 23). The Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to explore the potential signaling pathways of the changed metabolites. Under positive ion mode, a total of 29 metabolites were significantly altered in plasma between TR-ROP patients and controls, and 23 altered metabolites were identified under negative ion mode. KEGG analyses indicated that "protein digestion and absorption" and "aminoacyl-tRNA biosynthesis" were the most enriched pathways of the altered metabolites. These results demonstrated that metabolomic profiles changed in plasma of TR-ROP, and the altered metabolites could be served as potential biomarkers for the diagnosis and prognosis of TR-ROP patients. Besides, the metabolomic profiles might provide clues to discover novel therapeutic strategies in ROP treatment.

Serum levels of cytokines in infants treated with conbercept for retinopathy of prematurity.

Intravitreal anti-vascular endothelial growth factor (VEGF) agents have revolutionized the treatment of retinopathy of prematurity (ROP); however, there are concerns regarding the potential systemic complications caused by those treatments. This study aimed to determine the serum concentrations of cytokines in infants with ROP and to evaluate the changes in serum VEGF concentrations after intravitreal conbercept (IVC). Sixty infants with ROP treated with IVC 0.25 mg were included. Blood samples were collected before treatment as well as 1 week and 4 weeks after treatment. Serum levels of 45 types of cytokines were measured by a multiplex bead assay. We observed that IVC 0.25 mg in ROP patients suppressed the circulating levels of VEGF-A and VEGF-D as of 1 week after injection, and these growth factor levels returned to baseline at 4 weeks. No significant differences were observed in the serum levels of the other cytokines between baseline and 1 or 4 weeks after IVC.

Effects of Neonatal Hyperglycemia on Retinopathy of Prematurity and Visual Outcomes at 7 Years of Age: A Matched Cohort Study.

OBJECTIVE: To determine whether neonatal hyperglycemia is associated with retinopathy of prematurity (ROP), visual outcomes, and ocular growth at 7 years of age. STUDY DESIGN: Children born preterm (<30 weeks of gestational age) at a tertiary hospital in Auckland, New Zealand, who developed neonatal hyperglycemia (2 blood glucose concentrations ≥153 mg/dL [8.5 mmol/L] 4 hours apart) were matched with children who were not hyperglycemic (matching criteria: sex, gestational age, birth weight, age, socioeconomic status, and multiple birth) and assessed at 7 years of corrected age. The primary outcome, favorable overall visual outcome (visual acuity ≤0.3 logarithm of the minimum angle of resolution, no strabismus, stereoacuity ≤240 arcsec, not requiring spectacles) was compared between groups using generalized matching criteria-adjusted linear regression models. RESULTS: Assessments were performed on 57 children with neonatal hyperglycemia (hyperglycemia group) and 54 matched children without hyperglycemia (control group). There were no differences in overall favorable visual outcome (OR 0.95, 95% CI 0.42-2.13, P = .90) or severe ROP incidence (OR 2.20, 95% CI 0.63-7.63, P = .21) between groups. Children with hyperglycemia had poorer binocular distance visual acuity (mean difference 0.08, 95% CI 0.03-0.14 logarithm of the minimum angle of resolution, P < .01), more strabismus (OR 6.22, 95% CI 1.31-29.45, P = .02), and thicker crystalline lens (mean difference 0.14, 95% CI 0.04-0.24 mm, P < .01). Maximum blood glucose concentration was greater in the ROP-treated group compared with the ROP-not treated and no ROP groups after adjusting for sex, gestational age, and birth weight z score (P = .02). CONCLUSIONS: Neonatal hyperglycemia was not associated with overall visual outcomes at 7 years of age. However, there were between-group differences for specific outcome measures relating to interocular lens growth and binocular vision. Further follow-up is required to determine implications on long-term visual outcome.

Feasibility of neonatal haemoglobin A1C as a biomarker for retinopathy of prematurity.

INTRODUCTION: Retinopathy of prematurity (ROP) is a potentially serious eye disorder affecting very preterm infants. Non-proliferative ROP (NP-ROP), also known as Early Stage ROP, is characterized by deficient retinal angiogenesis. Proliferative ROP (P-ROP), also known as Late Stage ROP, is characterized by pathologic angiogenesis. The use of neonatal haemoglobin A1C as a biomarker for ROP has not yet been evaluated. MATERIALS AND METHODS: We modified the Haemoglobin A1C assay for use with neonatal dried blood spots (DBS) and then assessed A1C levels via Elisa immunoassay on DBS from 43 preterm infants (with gestational ages 26-28 weeks). We measured A1C on DBS collected at <1 week and 4 weeks of chronological age. RESULTS: Compared to matched counterparts without ROP, there is significantly lower HbA1c in infants who develop NP-ROP, this occurs at Week 4 (p=0.004), but is not seen at Week 1; there is significantly higher HbA1c in infants with P-ROP, this occurs both at Week 1 (p<0.05) and Week 4 (p=0.005). CONCLUSIONS: The A1C test, modified for use with DBS, is a feasible biomarker for ROP; low A1C is a potential biomarker for non-proliferative ROP and high A1C is for proliferative ROP.

A Comparison of Strategies for Managing the Umbilical Cord at Birth in Preterm Infants.

OBJECTIVE: To evaluate the rates of practice, and the associations between different cord management strategies at birth (delayed cord clamping [DCC], umbilical cord milking [UCM], and early cord clamping [ECC]) and mortality or major morbidity, rates of blood transfusion, and peak serum bilirubin in a large national cohort of very preterm infants. STUDY DESIGN: We retrospectively studied preterm infants <33 weeks of gestation admitted to the Canadian Neonatal Network between January 2015 and December 2017. Patients who received ECC (<30 seconds), UCM, or DCC (≥30 seconds) were compared. Multiple generalized linear/quantile logistic regression models were used. RESULTS: Of 12 749 admitted infants, 9729 were included; 4916 (50.5%) received ECC, 394 (4.1%) UCM, and 4419 (45.4%) DCC. After adjustment for potential confounders identified between groups in univariate analyses, the odds of mortality or major morbidity were higher in the ECC group when compared with UCM group (aOR, 1.18; 95% CI, 1.03-1.35). Mortality and intraventricular hemorrhage were associated with ECC as compared with DCC (aOR, 1.6 [95% CI, 1.22-2.1] and aOR, 1.29 [95% CI, 1.19-1.41], respectively). The odds of severe intraventricular hemorrhage were higher with UCM compared with DCC (aOR, 1.38; 95% CI, 1.05-1.81). Rates of blood transfusion were higher with ECC compared with UCM and DCC (aOR, 1.67 [95% CI, 1.31-2.14] and aOR, 1.68 [95% CI, 1.35-2.09], respectively), although peak serum bilirubin levels were not significantly different. CONCLUSIONS: Both DCC and UCM were associated with better short-term outcomes than ECC; however, the odds of severe intraventricular hemorrhage were higher with UCM compared with DCC.

Can Complete Blood Count Parameters Predict Retinopathy of Prematurity?

Objectives: To predict the risk of retinopathy of prematurity (ROP) development according to routine complete blood count (CBC) parameters. Materials and Methods: The medical records and CBC results of 150 premature neonates were retrospectively evaluated. As ROP develops 1 month after birth, first month CBC profiles of neonates without ROP (non-ROP), with ROP (ROP group), and those with Type 1, Type 2, and Stage 1+2 ROP were compared. Besides known statistical methods like Student's t-test, logistic regression and classification & regression tree (C&RT) analysis were also done to identify a reliable quantitative predictive parameter. Results: Mean gestational age and birth weight of the ROP group (n=99) and non-ROP (n=43) group were 29.39±3.43 and 32.05±2.20 weeks and 1382.44±545.30 and 1691.51±360.84 grams, respectively (p<0.001, p<0.001). Average hemoglobin (Hb) (p<0.001), hematocrit (HCT) (p<0.001), erythrocyte (p=0.005), mean corpuscular hemoglobin (MCH) (p=0.020), and MCH concentration (p=0.019) values of the ROP group were lower than those of the non-ROP group. Leukocyte was higher in the ROP group (p=0.018). Hb [odds ratio (OR)=0.668, 95% confidence interval (CI)=0.555-0.804, p<0.001], red cell distribution width (RDW) (OR=1.282, 95% CI=1.012-1.624, p=0.040), leukocyte (OR=1.157, 95% CI=1.053-1.271, p=0.002), and platelet (OR=0.997, 95% CI: 0.994-0.999, p=0.036) values differed significantly between the two groups. Platelet, MCV, and MCH parameters were found to be lower in the Type 1 ROP group compared to the Stage 1+2 ROP group (p<0.005). MCH was the most prominent predictor (cut-off: 34.43 pg) according to the results of C&RT analysis. Conclusion: As Hb plays an important role in oxygen transport, low levels of Hb and especially MCH may cause increased vascular endothelial growth factor secretion from the hypoxic retina, thereby causing ROP. Therefore, the results of this study are encouraging regarding the use of the abovementioned CBC parameters as a simple screening test to predict ROP.

Early versus late erythropoietin for preventing red blood cell transfusion in preterm and/or low birth weight infants.

BACKGROUND: Low plasma levels of erythropoietin (EPO) in preterm infants provide a rationale for the use of EPO to prevent or treat anaemia. OBJECTIVES: To assess the effectiveness and safety of early versus late initiation of EPO in reducing red blood cell (RBC) transfusions in preterm and/or low birth weight (LBW) infants. SEARCH METHODS: The standard search of the Cochrane Neonatal Review Group (CNRG) was performed in 2006 and updated in 2009. Updated search in September 2009 as follows: The Cochrane Library, MEDLINE (search via PubMed), CINAHL and EMBASE were searched from 2005 to September 2009. The searches were repeated in March 2012. The Pediatric Academic Societies' Annual meetings were searched electronically from 2000 to 2012 at Abstracts2ViewTM as were clinical trials registries (clinicaltrials.gov; controlled-trials.com; and who.int/ictrp). SELECTION CRITERIA: Randomised or quasi-randomised controlled trials enrolling preterm or LBW infants less than eight days of age. INTERVENTION: Early initiation of EPO (initiated at less than eight days of age) versus late initiation of EPO (initiated at eight to 28 days of age). DATA COLLECTION AND ANALYSIS: The standard methods of the CNRG were followed. Weighted treatment effects included typical risk ratio (RR), typical risk difference (RD), number needed to treat to benefit (NNTB), number needed to treat to harm (NNTH) and mean difference (MD), all with 95% confidence intervals (CI). A fixed-effect model was used for meta-analyses and heterogeneity was evaluated using the I-squared (I2) test. MAIN RESULTS: No new trials were identified in March of 2012. Two high quality randomised double-blind controlled studies enrolling 262 infants were identified. A non-significant reduction in the 'Use of one or more RBC transfusions' [two studies 262 infants; typical RR 0.91 (95% CI 0.78 to 1.06); typical RD -0.07 (95% CI -0.18 to 0.04; I2 = 0% for both RR and RD] favouring early EPO was noted. Early EPO administration resulted in a non-significant reduction in the "number of transfusions per infant" compared with late EPO [typical MD - 0.32 (95% CI -0.92 to 0.29)]. There was no significant reduction in total volume of blood transfused per infant or in the number of donors to whom the infant was exposed. Early EPO led to a significant increase in the risk of retinopathy of prematurity (ROP) (all stages) [two studies, 191 infants; typical RR 1.40 (95% CI 1.05 to 1.86); typical RD 0.16 (95% CI 0.03 to 0.29); NNTH 6 (95% CI 3 to 33)]. There was high heterogeneity for this outcome (I2 = 86% for RR and 81% for RD). Both studies (191 infants) reported on ROP stage > 3. No statistically significant increase in risk was noted [typical RR 1.56 (95% CI 0.71 to 3.41); typical RD 0.05 (-0.04 to 0.14)] There was no heterogeneity for this outcome (0% for both RR and RD). No other important favourable or adverse neonatal outcomes or side effects were reported. AUTHORS' CONCLUSIONS: The use of early EPO did not significantly reduce the 'Use of one or more RBC transfusions' or the 'Number of transfusions per infant" compared with late EPO administration. The finding of a statistically significant increased risk of ROP (any grade) and a similar trend for ROP stage > 3 with early EPO treatment is of great concern.

Early erythropoiesis-stimulating agents in preterm or low birth weight infants.

BACKGROUND: Preterm infants have low plasma levels of erythropoietin (EPO), providing a rationale for the use of erythropoiesis-stimulating agents (ESAs) to prevent or treat anaemia and to provide neuro protection and protection against necrotising enterocolitis (NEC). Darbepoetin (Darbe) and EPO are currently available ESAs. OBJECTIVES: To assess the effectiveness and safety of ESAs (erythropoietin (EPO) and/or Darbe) initiated early (before eight days after birth) compared with placebo or no intervention in reducing red blood cell (RBC) transfusions, adverse neurological outcomes, and feeding intolerance including necrotising enterocolitis (NEC) in preterm and/or low birth weight infants. Primary objective for studies that primarily investigate the effectiveness and safety of ESAs administered early in reducing red blood cell transfusions: To assess the effectiveness and safety of ESAs initiated early in reducing red blood cell transfusions in preterm infants. Secondary objectives: Review authors performed subgroup analyses of low (≤ 500 IU/kg/week) and high (> 500 IU/kg/week) doses of EPO and the amount of iron supplementation provided: none, low (≤ 5 mg/kg/d), and high (> 5 mg/kg/d). Primary objective for studies that primarily investigate the neuro protective effectiveness of ESAs: To assess the effectiveness and safety of ESAs initiated early in reducing adverse neurological outcomes in preterm infants. Primary objective for studies that primarily investigate the effectiveness of EPO or Darbe administered early in reducing feeding intolerance: To assess the effectiveness and safety of ESAs administered early in reducing feeding intolerance (and NEC) in preterm infants. Other secondary objectives: To compare the effectiveness of ESAs in reducing the incidence of adverse events and improving long-term neurodevelopmental outcomes. SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), MEDLINE via PubMed (1966 to 10 March 2017), Embase (1980 to 10 March 2017), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 10 March 2017). We searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised and quasi-randomised controlled trials. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials of early initiation of EAS treatment versus placebo or no intervention in preterm or low birth weight infants. DATA COLLECTION AND ANALYSIS: We used the methods described in the Cochrane Handbook for Systematic Reviews of Interventions and the GRADE approach to assess the quality of evidence. MAIN RESULTS: This updated review includes 34 studies enrolling 3643 infants. All analyses compared ESAs versus a control consisting of placebo or no treatment. Early ESAs reduced the risk of 'use of one or more [red blood cell] RBC transfusions' (typical risk ratio (RR) 0.79, 95% confidence interval (CI) 0.74 to 0.85; typical risk difference (RD) -0.14, 95% CI -0.18 to -0.10; I2 = 69% for RR and 62% for RD (moderate heterogeneity); number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 6 to 10; 19 studies, 1750 infants). The quality of the evidence was low. Necrotising enterocolitis was significantly reduced in the ESA group compared with the placebo group (typical RR 0.69, 95% CI 0.52 to 0.91; typical RD -0.03, 95% CI -0.05 to -0.01; I2 = 0% for RR and 22% for RD (low heterogeneity); NNTB 33, 95% CI 20 to 100; 15 studies, 2639 infants). The quality of the evidence was moderate. Data show a reduction in 'Any neurodevelopmental impairment at 18 to 22 months' corrected age in the ESA group (typical RR 0.62, 95% CI 0.48 to 0.80; typical RD -0.08, 95% CI -0.12 to -0.04; NNTB 13, 95% CI 8 to 25. I2 = 76% for RR (high heterogeneity) and 66% for RD (moderate); 4 studies, 1130 infants). The quality of the evidence was low. Results reveal increased scores on the Bayley-II Mental Development Index (MDI) at 18 to 24 months in the ESA group (weighted mean difference (WMD) 8.22, 95% CI 6.52 to 9.92; I2 = 97% (high heterogeneity); 3 studies, 981 children). The quality of the evidence was low. The total volume of RBCs transfused per infant was reduced by 7 mL/kg. The number of RBC transfusions per infant was minimally reduced, but the number of donors to whom infants who were transfused were exposed was not significantly reduced. Data show no significant difference in risk of stage ≥ 3 retinopathy of prematurity (ROP) with early EPO (typical RR 1.24, 95% CI 0.81 to 1.90; typical RD 0.01, 95% CI -0.02 to 0.04; I2 = 0% (no heterogeneity) for RR; I2 = 34% (low heterogeneity) for RD; 8 studies, 1283 infants). Mortality was not affected, but results show significant reductions in the incidence of intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL). AUTHORS' CONCLUSIONS: Early administration of ESAs reduces the use of red blood cell (RBC) transfusions, the volume of RBCs transfused, and donor exposure after study entry. Small reductions are likely to be of limited clinical importance. Donor exposure probably is not avoided, given that all but one study included infants who had received RBC transfusions before trial entry. This update found no significant difference in the rate of ROP (stage ≥ 3) for studies that initiated EPO treatment at less than eight days of age, which has been a topic of concern in earlier versions of this review. Early EPO treatment significantly decreased rates of IVH, PVL, and NEC. Neurodevelopmental outcomes at 18 to 22 months and later varied in published studies. Ongoing research should evaluate current clinical practices that will limit donor exposure. Promising but conflicting results related to the neuro protective effect of early EPO require further study. Very different results from the two largest published trials and high heterogeneity in the analyses indicate that we should wait for the results of two ongoing large trials before drawing firm conclusions. Administration of EPO is not currently recommended because limited benefits have been identified to date. Use of darbepoetin requires further study.

Prediction of severe retinopathy of prematurity using the weight gain, insulin-like growth factor 1, and neonatal retinopathy of prematurity algorithm in a Japanese population of preterm infants.

PURPOSE: To retrospectively investigate the sensitivity and specificity of weight gain, insulin-like growth factor 1, and neonatal retinopathy of prematurity (WINROP) algorithm for the prediction of severe retinopathy of prematurity (ROP) in a Japanese population of preterm infants. The WINROP algorithm is a tool based on postnatal weight gain. STUDY DESIGN: Retrospective cohort study. METHODS: The medical records of preterm infants born between January 2011 and March 2017 were retrospectively reviewed. Infants born after 33 weeks of gestation were excluded based on the indications of the WINROP algorithm. Postnatal weight was recorded weekly on the WINROP system until postmenstrual week 36. The sensitivity and specificity of the WINROP algorithm were analyzed. RESULTS: In total, 278 infants were included in this study. Based on the WINROP algorithm 110 of these infants were predicted to be at low risk for developing severe ROP and 105 did not develop severe ROP. Based on the WINROP algorithm 168 infants were predicted to be at high risk for developing severe ROP　and 27 developed severe ROP. Thus, the sensitivity of the WINROP algorithm was 84.4% and the specificity 42.7%. CONCLUSION: The WINROP algorithm could be used for preterm infants (gestational age of <28 weeks) without a complicated hospital course. Modification of the algorithm will improve its sensitivity and specificity for the Japanese population.

Impact of Platelet Count in Retinopathy of Prematurity.

Objectives: The aim of the study was to investigate the risk factors for retinopathy of prematurity (ROP), including platelet count. Materials and Methods: This retrospective study analyzed 137 infants in 3 subgroups: no ROP; mild ROP, and severe ROP requiring laser treatment (type 1 ROP). A retrospective review of records was performed and statistical analysis of possible risk factors for ROP including platelet count was evaluated by using logistic regression. Results: Birth weight (BW), gestational age (GA), and low platelet count in the first week after birth were significant risk factors for developing ROP (p=0.038, 0.02, and 0.004, respectively). BW, GA, ventilation, and lower platelet count were associated with progression to type 1 ROP (p=0.004; 0.027, and 0.021, respectively). Conclusion: Lower platelet count in the first week after birth is a risk factor for ROP development in addition to the previously established factors of ventilation need, low BW, and low GA.

The postnatal presence of human chorionic gonadotropin in preterm infants and its potential inverse association with retinopathy of prematurity.

BACKGROUND: Human chorionic gonadotropin (hCG) and luteinizing hormone (LH) are pro-angiogenic gonadotropic hormones, which classically target the reproductive organs. However, hCG, LH, and their shared CG/LH receptor are also present in the human eye. The possibility that a deficiency of these hormones may be involved in the pathogenesis of retinopathy of prematurity (ROP) during its early non-proliferative phase has not been explored. METHODS: We conducted a cross-sectional study of Michigan-born preterm infants utilizing dried blood spots. We analyzed hCG and LH blood levels at 1 week and 4 weeks of age from 113 study participants (60 without ROP; 53 with non-proliferative ROP). We utilized electrochemiluminescence assays on the Mesoscale Discovery platform. RESULTS: Similar levels of hCG are found in preterm infants at both 1 week and 4 weeks after birth. Preterm infants with non-proliferative ROP, after adjusting for sex and gestational age, have 2.42 [95% CI: 1.08-5.40] times the odds of having low hCG at fourth week of age. CONCLUSIONS: We found that hCG is present postnatally in preterm infants and that a deficiency of hCG at 4 weeks of age is potentially associated with non-proliferative ROP. This provides novel evidence to suggest that hCG may participate in human retinal angiogenesis.

Short- and long-term impact of hyperoxia on the blood and retinal cells' transcriptome in a mouse model of oxygen-induced retinopathy.

BACKGROUND: We aimed to identify global blood and retinal gene expression patterns in murine oxygen-induced retinopathy (OIR), a common model of retinopathy of prematurity, which may allow better understanding of the pathogenesis of this severe ocular prematurity complication and identification of potential blood biomarkers. METHODS: A total of 120 C57BL/6J mice were randomly divided into an OIR group, in which 7-day-old pups were maintained in 75% oxygen for 5 days, or a control group. RNA was extracted from the whole-blood mononuclear cells and retinal cells on days 12, 17, and 28. Gene expression in the RNA samples was evaluated with mouse gene expression microarrays. RESULTS: There were 38, 1370 and 111 genes, the expression of which differed between the OIR and control retinas on days 12, 17, and 28, respectively. Gene expression in the blood mononuclear cells was significantly altered only on day 17. Deptor and Nol4 genes showed reduced expression both in the blood and retinal cells on day 17. CONCLUSION: There are sustained marked changes in the global pattern of gene expression in the OIR mice retinas. An altered expression of Deptor and Nol4 genes in the blood mononuclear cells requires further investigation as they may indicate retinal neovascularization.

Achieved oxygen saturations and retinopathy of prematurity in extreme preterms.

OBJECTIVE: To identify achieved oxygen saturations (SpO2) associated with increased risk of severe retinopathy of prematurity (ROP). DESIGN: This is a secondary analysis of the Surfactant Positive Airway Pressure and Pulse Oximetry Trial (SUPPORT)randomised controlled trial. SpO2 was recorded up to 36 weeks' postmenstrual age. Saturations through 9 postnatal weeks were explored graphically, and logistic regression models were created to predict severe ROP. SETTING: 20 centres of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. PATIENTS: 984 surviving infants of 24-27 weeks' gestational age born in 2005-2009. INTERVENTIONS: SUPPORT targeted SpO2 to a lower (85%-89%) or higher (91%-95%) range through 36 weeks' postmenstrual age or off respiratory support. MAIN OUTCOME MEASURES: Severe ROP defined as threshold ROP, ophthalmological surgery or bevacizumab treatment. RESULTS: There were statistically significant interactions between duration of oxygen supplementation and percentage of time in certain achieved saturation ranges. Specifically, for infants who spent at least 2 weeks on oxygen in postnatal weeks 1-5, a higher percentage of time at 91%-96% SpO2 was associated with increased odds of severe ROP. For infants who spent at least 3 weeks on oxygen in postnatal weeks 6-9, a higher percentage of time at 97%-100% SpO2 was associated with increased odds of severe ROP. Other significant risk factors were lower gestational age and birth weight, non-Hispanic white versus black race, prospectively defined severe illness, late-onset sepsis or meningitis, and clinical centre. CONCLUSIONS: Among extremely preterm survivors to discharge, the association between SpO2 and severe ROP depended on the timing and duration of oxygen supplementation.

Metabolomic changes of blood plasma associated with two phases of rat OIR.

Although acute hyperoxia/hypoxia alternation can shift sharply physiological processes of vessel development, e.g. oxygen induced retinopathy (OIR), very little is known of metabolic products resulted from the neovascularization disorder. In this study, the influence of abnormal oxygen exposures on the plasma metabolomic profiles of rats with OIR was investigated by the gas chromatography mass spectrometry (GC-MS). Rat pups were divided into four groups, each with 12 individuals: (i) reared in room air and sampled at P12 (CT1); (ii) exposed to high oxygen for 5 days and sampled at P12 (HO1, simulating the vaso-obeliteration process (phase I)); (iii) reared in room air and sampled at P17 (CT2); (iv) exposed to high oxygen for 5 days then followed by room air for 5 days and sampled at P17 (HO2, simulating the neovasculization one (phase II)). Plasma samples were analyzed with GC-MS, resulted in 122 metabolite species. Distinct differences in the plasma metabolome were found between groups of CT1 vs. HO1, and HO1 vs. HO2, by using univariate and multivariate analyses. Alternating hyperoxia/hypoxia conditions induced significant changes of richness of proline, ornithine and glutamine, that were important components of 'arginine and proline metabolism' pathway. These metabolites contributed largely to plasma sample classification, determined with receiver operating characteristic curve analysis and were involved profoundly in the proline-dependent production of reactive oxygen species (ROS) related to the cellular redox reactions. Our results from the rat OIR model suggest proline and 'arginine and proline metabolism' pathway as the potential biomarkers for human retinopathy of prematurity (ROP) diagnosis.