Longitudinal Assessment of Preterm Infants Treated with Erythropoiesis Stimulating Agents.

OBJECTIVE: We previously reported improved neurodevelopment at 2 and 4 years among preterm infants treated with erythropoietin or darbepoetin, known as erythropoiesis-stimulating agents (ESAs). We now characterize longitudinal outcomes through 6 years. METHODS: Children randomized to ESAs or placebo were evaluated at 6 years. Healthy-term children served as controls. Tests of cognition and executive function (EF) were performed. RESULTS: Cognitive/EF scores remained similar between 4 and 6 years within each group (ESA: 43 children; placebo: 17 children; term: 21 children). ESA recipients scored higher than placebo on Full-Scale IQ (94.2 ± 18.6 vs. 81.6 ± 16.7, p = 0.022), and Performance IQ (97.3 ± 16.2 vs. 81.7 ± 15.2, = 0.005). Aggregate EF trended better for the ESA group. Term controls scored better than placebo on all measures. ESA and term controls scored similarly on cognitive and EF tests. CONCLUSION: ESA recipients had better outcomes than placebo recipients, and were similar to term children. ESAs may improve long-term cognition and executive function in preterm infants.

Effect of blood transfusions on cognitive development in very low birth weight infants.

OBJECTIVE: Preterm infants frequently receive red cell transfusions; however, the effect of transfusions on cognition is unclear. We evaluated the relationship between transfusions and cognitive outcomes in preterm infants enrolled in a randomized trial of erythropoiesis stimulating agents (ESAs). STUDY DESIGN: Preterm infants were randomized to ESAs or placebo during initial hospitalization, and transfusions recorded. Children were evaluated using standard developmental tests of cognition at 18-22 months (56 ESA, 24 placebo) and 3.5-4 years (39 ESA, 14 placebo). RESULTS: Cognitive scores at 18-22 months were inversely correlated with transfusion volume (p = 0.02). Among those receiving ≥1 transfusion, cognitive scores were significantly higher in the ESA-treated group (p = 0.003). At 3.5-4 years, transfusions were not correlated with cognitive scores. CONCLUSIONS: In the placebo group, transfused children had lower cognitive scores than did non-transfused children at 18-22 months. In the ESA group, cognitive scores did not differ by transfusion status, suggesting ESAs might provide neuroprotection.

Neonatal Outcomes Associated with Umbilical Cord Milking in Preterm Multiple Gestations.

OBJECTIVE: Our aim was to evaluate the effect of umbilical cord milking on outcomes for preterm multiples. STUDY DESIGN: We implemented a policy of cord milking in neonates born at less than 30 weeks' gestation in September 2011. We compared cord milking in multiples with a historical cohort. Multivariable logistic regression models estimated the effect of cord milking on a composite neonatal adverse outcome. Secondary outcomes were hematocrit at birth, need for blood transfusion, and inotrope use. RESULTS: We identified 149 neonates (120 twins, 29 triplets), 51 historical controls, and 98 neonates with cord milking. Cord milking was associated with a lower rate of adverse composite neonatal outcome in univariable analysis (odds ratio [OR]: 0.36; 95% confidence interval [CI]: 0.15-0.84). However, in multivariable modeling, the effect was not significant (adjusted OR [aOR]: 0.54, 95% CI: 0.23-1.28). Hematocrit was 4.6 unit % (95% CI: 2-7.3) higher in the cord milking group, and cord milking was associated with a lower rate of blood transfusion (aOR: 0.28; 95% CI: 0.1-0.74; p = 0.01). There was no difference in inotrope administration. CONCLUSION: Umbilical cord milking was not associated with a decrease in composite neonatal adverse outcome. However, we observed an increase in hematocrit and decreased need for blood transfusion in neonates with cord milking.

Reducing Unplanned Extubations in the NICU Following Implementation of a Standardized Approach.

BACKGROUND: Unplanned extubations (UEs) have been associated with increased ventilator days, risk of infection, cardiopulmonary resuscitation, and resuscitation medication usage. The UE rate in our level 4 NICU is lower than the national average. Efforts to further reduce UE events at our institution led an interdisciplinary group to define steps to eliminate UEs. Steps included: (1) requiring at least 2 care providers at the bedside for movement of an intubated subject; (2) standardizing head and endotracheal tube (ETT) position; (3) defining a set methodology for ETT securing; (4) introducing a postoperative handoff to improve communication; and (5) implementing a post-UE assessment tool. METHODS: A quality improvement initiative reviewed subjects and compared UE rates before (January 2013 to December 2013) and after (January 2014 to December 2014) implementation of UE prevention guidelines. A de-identified data set was used for analysis. RESULTS: 67 UE events were identified with 46 UE events at baseline in 2013 compared with 21 in 2014 post-implementation. This amounted to a 64% decrease in total UE events (from 46 to 21) (P < .001). Additionally, monthly UE rates decreased 50% (from 3.8 to 1.9), and UE events per 100 ventilator days decreased 53% (from 1.15 to 0.54). CONCLUSIONS: The development of standard guidelines to prevent UE and a quality review process to track UE provided important information for education and practice change. In our NICU, these changes have significantly improved the UE rate through improved teamwork, accountability, and communication.

Neuroimaging in former preterm children who received erythropoiesis stimulating agents.

BackgroundIn premature children, erythropoiesis-stimulating agents (ESAs) may improve developmental outcome. It is not clear which of the several potential mechanisms are responsible for this improvement. High-resolution MRI and diffusion tensor imaging characterize brain structure and white matter organization, offering possible insight into the long-term effect of ESAs on brain development.MethodsMRI scans were performed at 3.5-4 years of age on former preterm infants treated with ESAs or placebo, and on healthy term controls. Mean cortical thickness, surface area, and fractional anisotropy (FA) were compared across study groups, and were correlated with general IQ measures.ResultsUnivariate analysis found no significant effect of ESAs on cortical thickness (P=0.366), surface area (P=0.940), or FA (P=0.150); however, there was a greater increase in FA among ESA-treated girls. Group analysis found significant correlations between FA and Full-Scale IQ (P=0.044) and Verbal IQ (P=0.036), although there was no significant relationship between Full-Scale IQ and FA among just the preterm children.ConclusionESA treatment may have a preferential effect on white matter development in girls, although factors other than just whole-brain FA are involved in mediating cognitive outcome.

Impact of Erythropoiesis-Stimulating Agents on Behavioral Measures in Children Born Preterm.

OBJECTIVE: To evaluate the impact of erythropoiesis-stimulating agents (ESAs) administered during initial hospitalization and family demographic factors on behavior at 3.5-4 years of age. STUDY DESIGN: Children were enrolled who had previously participated in a randomized study of ESAs (n = 35) or placebo (n = 14) in infants born preterm with birth weights of 500-1250 g. A term healthy control group (n = 22) also was recruited. Behavior was evaluated by parent report with the Behavioral Assessment System of Children-2. Principal component analyses identified 2 demographic factors, a Socioeconomic Composite (SEC) and a Family Stress Composite. A multivariate general linear model evaluated the impact of study group and sex on the 4 composite scales of the Behavioral Assessment System of Children-2. Demographic factors were treated as covariates and interactions with study group (ESA, placebo, and term) were examined. RESULTS: The ESA group had significantly better scores than the placebo group on behavioral symptoms (P = .04) and externalizing scales (P = .04). An interaction was observed between study group and SEC (P = .001). A beneficial effect of ESAs was maximal in the children with lower SEC scores. CONCLUSIONS: The beneficial effects of ESAs on childhood behavior were maximal in children with lower SEC scores. ESAs seemed to ameliorate the adverse impact of lower SEC on behavioral domains seen in the placebo group. This effect was independent of the beneficial effect of ESAs on global cognition we reported previously. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01207778 and NCT00334737.

Preschool Assessment of Preterm Infants Treated With Darbepoetin and Erythropoietin.

BACKGROUND: We previously reported improved neurodevelopmental outcomes at 2 years among infants treated with the erythropoiesis-stimulating agents (ESAs) darbepoetin alfa (darbepoetin) or erythropoietin. Here we characterize 4-year outcomes. METHODS: Former preterm infants randomly assigned to receive darbepoetin (10 µg/kg, once per week), erythropoietin (400 U/kg, 3 times/week), or placebo through 35 weeks' postconceptual age were evaluated at 3.5 to 4 years of age. For comparison, healthy children formerly delivered full term (term controls [TCs]) were also recruited. All participants were assessed by using measures of full-scale IQ (FSIQ) and general language from the Wechsler Preschool and Primary Scale of Intelligence, Third Edition, and an overall measure of executive function, on the basis of tests evaluating inhibitory control and spatial working memory. Rates of neurodevelopmental impairment were compared across groups. RESULTS: Multivariate analysis of variance compared children randomly assigned to ESAs (n = 39), placebo (n =14), and TCs (n = 24). FSIQ and performance IQ were significantly higher in the ESA group than in the placebo group (FSIQ: 91.1 ± 17.5 vs 79.2 ± 18.5, P = .036; performance IQ: 93.0 ± 17.0 vs 79.5 ± 19.5, P = .018). Follow-up analyses revealed that the children receiving ESAs performed better than those who received placebo on executive function tasks. The ESA group's performance was below that of TCs, but the results did not reach significance on executive function. The incidence of neurodevelopmental impairment was greater in the placebo group than in the ESA group. CONCLUSIONS: ESA-treated infants had better cognitive outcomes and less developmental impairment at 3.5 to 4 years of age compared with placebo-treated infants. ESAs show promise in improving long-term cognitive outcomes of infants born prematurely.

Darbepoetin Administration in Term and Preterm Neonates.

Erythropoiesis-stimulating agents (ESAs) such as erythropoietin have been studied as red cell growth factors in preterm and term infants for more than 20 years. Recent studies have evaluated darbepoetin (Darbe, a long-acting ESA) for both erythropoietic effects and potential neuroprotection. We review clinical trials of Darbe in term and preterm infants, which have reported significant erythropoietic uses and neuroprotective effects. ESAs show great promise in decreasing or eliminating transfusions, and in preventing and treating brain injury in term and preterm infants.

Effect of umbilical cord milking on morbidity and survival in extremely low gestational age neonates.

OBJECTIVE: Delayed umbilical cord clamping benefits extremely low gestational age neonates (ELGANs) but has not gained wide acceptance. We hypothesized that milking the umbilical cord (MUC) would avoid resuscitation delay but improve hemodynamic stability and reduce rates for composite outcome of severe intraventricular hemorrhage, necrotizing enterocolitis, and/or death before discharge. STUDY DESIGN: We implemented a joint neonatal/maternal-fetal quality improvement process for MUC starting September 2011. The MUC protocol specified that infants who were born at <30 weeks of gestation undergo MUC 3 times over a duration of <30 seconds at delivery. Obstetric and neonatal data were collected until discharge. We compared the MUC group to retrospective ELGAN cohort delivered at our center between January 2010 and August 2011. Analysis was intention-to-treat. RESULTS: We identified 318 ELGANs: 158 eligible for MUC and 160 retrospective control neonates. No adverse events were reported with cord milking. There was no difference in neonatal resuscitation, Apgar scores, or admission temperature. Hemodynamic stability was improved in the MUC group with higher mean blood pressures through 24 hours of age, despite less vasopressor use (18% vs 32%; P < .01). The initial hematocrit value was higher (50% vs 45%; P < .01), and red cell transfusions were fewer (57% vs 79%; P < .01) in MUC vs control infants. Presence of the composite outcome was significantly less in MUC vs the historic control infants (22% v 39%; odds ratio, 1.81; 95% confidence interval, 1.06-3.10). There were also reductions in intraventricular hemorrhage, necrotizing enterocolitis, and death before hospital discharge. CONCLUSION: MUC improves early hemodynamic stability and is associated with lower rates of serious morbidity and death among ELGANs.

Toll-like receptor 3 and geographic atrophy in age-related macular degeneration.

BACKGROUND: Age-related macular degeneration is the most common cause of irreversible visual impairment in the developed world. Advanced age-related macular degeneration consists of geographic atrophy and choroidal neovascularization. The specific genetic variants that predispose patients to geographic atrophy are largely unknown. METHODS: We tested for an association between the functional toll-like receptor 3 gene (TLR3) variant rs3775291 (involving the substitution of phenylalanine for leucine at amino acid 412) and age-related macular degeneration in Americans of European descent. We also tested for the effect of TLR3 Leu and Phe variants on the viability of human retinal pigment epithelial cells in vitro and on apoptosis of retinal pigment epithelial cells from wild-type mice and Tlr3-knockout (Tlr3(-/-)) mice. RESULTS: The Phe variant (encoded by the T allele at rs3775291) was associated with protection against geographic atrophy (P=0.005). This association was replicated in two independent case-control series of geographic atrophy (P=5.43x10(-4) and P=0.002). No association was found between TLR3 variants and choroidal neovascularization. A prototypic TLR3 ligand induced apoptosis in a greater fraction of human retinal pigment epithelial cells with the Leu-Leu genotype than those with the Leu-Phe genotype and in a greater fraction of wild-type mice than Tlr3(-/-) mice. CONCLUSIONS: The TLR3 412Phe variant confers protection against geographic atrophy, probably by suppressing the death of retinal pigment epithelial cells. Since double-stranded RNA (dsRNA) can activate TLR3-mediated apoptosis, our results suggest a role of viral dsRNA in the development of geographic atrophy and point to the potential toxic effects of short-interfering-RNA therapies in the eye.

Genetic susceptibility of diabetic retinopathy.

Diabetes continues to be a major source of -morbidity and mortality among working-age adults nationally and internationally. The microvascular complications of diabetes, including diabetic retinopathy, account for a major proportion of disease-associated morbidity and likely contribute to macrovascular complications. Although glycemic control contributes to -susceptibility for diabetic complications, some people with strict control develop these complications, whereas -others with poor control remain complication free. This suggests a genetic contribution to disease development. Although many genes and proteins of vascular growth have been studied in association with diabetic retinopathy, no definitive major predisposing genes or functional consequences of genetic variants have been identified for microvascular complications of the disease. In this article, we review the studies done on candidate genes.

Promoter polymorphism of the erythropoietin gene in severe diabetic eye and kidney complications.

Significant morbidity and mortality among patients with diabetes mellitus result largely from a greatly increased incidence of microvascular complications. Proliferative diabetic retinopathy (PDR) and end stage renal disease (ESRD) are two of the most common and severe microvascular complications of diabetes. A high concordance exists in the development of PDR and ESRD in diabetic patients, as well as strong familial aggregation of these complications, suggesting a common underlying genetic mechanism. However, the precise gene(s) and genetic variant(s) involved remain largely unknown. Erythropoietin (EPO) is a potent angiogenic factor observed in the diabetic human and mouse eye. By a combination of case-control association and functional studies, we demonstrate that the T allele of SNP rs1617640 in the promoter of the EPO gene is significantly associated with PDR and ESRD in three European-American cohorts [Utah: P = 1.91 x 10(-3); Genetics of Kidneys in Diabetes (GoKinD) Study: P = 2.66 x 10(-8); and Boston: P = 2.1 x 10(-2)]. The EPO concentration in human vitreous body was 7.5-fold higher in normal subjects with the TT risk genotype than in those with the GG genotype. Computational analysis suggests that the risk allele (T) of rs1617640 creates a matrix match with the EVI1/MEL1 or AP1 binding site, accounting for an observed 25-fold enhancement of luciferase reporter expression as compared with the G allele. These results suggest that rs1617640 in the EPO promoter is significantly associated with PDR and ESRD. This study identifies a disease risk-associated gene and potential pathway mediating severe diabetic microvascular complications.

Elevated erythropoietin mRNA and protein concentrations in the developing human eye.

Erythropoietin (Epo) is an erythropoietic, neurotropic, and angiogenic factor, and may be involved in retinal development. Studies in adult diabetic retinopathy patients reveal significantly elevated vitreal Epo concentrations. It is unknown whether Epo plays a similar role in retinopathy of prematurity. We sought to determine whether Epo is present in the normally developing human eye. Fetal serum and vitreous samples were obtained from 12 to 24 wk gestation. RNA was extracted from isolated retina for Epo mRNA and hypoxia inducible factor-1alpha (HIF) mRNA determination by real-time polymerase chain reaction. Fetal serum was isolated from the umbilical cord. Serum and vitreous samples were analyzed for Epo protein by enzyme-linked immunosorbent serologic assay. In fetal retina, Epo mRNA increased with increasing gestational age, while HIF mRNA remained constant. Epo protein increased with increasing gestation in both vitreous and serum. At each gestational group measured (12-14, 15-17, 18-20, and 21-24 wk), Epo concentrations were significantly greater in vitreous than in serum (p < 0.05). Epo mRNA and protein concentrations increase with increasing gestational age and are greater in the vitreous than serum. We speculate that changes in Epo production following preterm delivery might affect retinal vascular development.

Familial aggregation of age-related macular degeneration in the Utah population.

We examined familial aggregation and risk of age-related macular degeneration in the Utah population using a population-based case-control study. Over one million unique patient records were searched within the University of Utah Health Sciences Center and the Utah Population Database (UPDB), identifying 4764 patients with AMD. Specialized kinship analysis software was used to test for familial aggregation of disease, estimate the magnitude of familial risks, and identify families at high risk for disease. The population-attributable risk (PAR) for AMD was calculated to be 0.34. Recurrence risks in relatives indicate increased relative risks in siblings (2.95), first cousins (1.29), second cousins (1.13), and parents (5.66) of affected cases. There were 16 extended large families with AMD identified for potential use in genetic studies. Each family had five or more living affected members. The familial aggregation of AMD shown in this study exemplifies the merit of the UPDB and supports recent research demonstrating significant genetic contribution to disease development and progression.