[EPIPAGE: epidemiologic study of very premature infants. Protocol of the survey]

Factors associated with non-nutritive sucking habits at 2 years of age among very preterm children: EPIPAGE-2 cohort study

BACKGROUND

The association between prolonged non-nutritive sucking habits (NNSHs, ie, sucking pacifiers or fingers) and maxillofacial growth anomalies in the general population has been widely described. Because maturation of sucking abilities is not fully achieved in very preterm infants (<32 weeks' gestation), neonatal services worldwide rely on the use of pacifiers to promote the development of adequate sucking reflexes, possibly prolonging NNSHs during infancy.

OBJECTIVE

We aimed to describe the frequency and to identify factors associated with NNSHs at age 2 years in very preterm children.

METHODS

The study was based on data from EPIPAGE-2, a French national prospective cohort study of preterm births during 2011 that included 2593 children born between 24 and 31 weeks' gestation. The primary outcome was NNSHs at 2 years. Multivariable log-linear regression models with generalized estimation equations were used to study the association between the characteristics studied and NNSHs. Multiple imputations were used to take into account missing data.

RESULTS

The frequency of NNSHs was 69% in the overall sample but higher among girls (adjusted risk ratio [RR] 1.12, 95% confidence interval [CI] 1.05, 1.17), children born from multiple pregnancies (eg, twins/triplets) (RR 1.07, 95% CI 1.00, 1.11), children who were fed by nasogastric tube (RR 1.07, 95% CI 1.01, 1.13), or those who benefitted from developmental care programmes (RR 1.10, 95% CI 1.02, 1.19). The NNSHs frequency was lower if mothers were not born in France (RR 0.70, 95% CI 0.64, 0.77), children had 2 or more older siblings (RR 0.88, 95% CI 0.82, 0.96), or children were breast-fed at discharge (RR 0.90, 95% CI 0.85, 0.95).

CONCLUSIONS

NNSHs at 2 years seemed associated with cultural background, development care programmes, and breast feeding. Whether NNSHs at 2 years among very preterm children are associated with future maxillofacial growth anomalies deserves further attention.

Neurodevelopmental outcome at 2 years for preterm children born at 22 to 34 weeks' gestation in France in 2011: EPIPAGE-2 cohort study

Objectives To describe neurodevelopmental outcomes at 2 years corrected age for children born alive at 22-26, 27-31, and 32-34 weeks' gestation in 2011, and to evaluate changes since 1997.Design Population based cohort studies, EPIPAGE and EPIPAGE-2.Setting France.Participants 5567 neonates born alive in 2011 at 22-34 completed weeks' gestation, with 4199 survivors at 2 years corrected age included in follow-up. Comparison of outcomes reported for 3334 (1997) and 2418 (2011) neonates born alive in the nine regions participating in both studies.Main outcome measures Survival; cerebral palsy (2000 European consensus definition); scores below threshold on the neurodevelopmental Ages and Stages Questionnaire (ASQ; at least one of five domains below threshold) if completed between 22 and 26 months corrected age, in children without cerebral palsy, blindness, or deafness; and survival without severe or moderate neuromotor or sensory disabilities (cerebral palsy with Gross Motor Function Classification System levels 2-5, unilateral or bilateral blindness or deafness). Results are given as percentage of outcome measures with 95% confidence intervals.Results Among 5170 liveborn neonates with parental consent, survival at 2 years corrected age was 51.7% (95% confidence interval 48.6% to 54.7%) at 22-26 weeks' gestation, 93.1% (92.1% to 94.0%) at 27-31 weeks' gestation, and 98.6% (97.8% to 99.2%) at 32-34 weeks' gestation. Only one infant born at 22-23 weeks survived. Data on cerebral palsy were available for 3599 infants (81.0% of the eligible population). The overall rate of cerebral palsy at 24-26, 27-31, and 32-34 weeks' gestation was 6.9% (4.7% to 9.6%), 4.3% (3.5% to 5.2%), and 1.0% (0.5% to 1.9%), respectively. Responses to the ASQ were analysed for 2506 children (56.4% of the eligible population). The proportion of children with an ASQ result below threshold at 24-26, 27-31, and 32-34 weeks' gestation were 50.2% (44.5% to 55.8%), 40.7% (38.3% to 43.2%), and 36.2% (32.4% to 40.1%), respectively. Survival without severe or moderate neuromotor or sensory disabilities among live births increased between 1997 and 2011, from 45.5% (39.2% to 51.8%) to 62.3% (57.1% to 67.5%) at 25-26 weeks' gestation, but no change was observed at 22-24 weeks' gestation. At 32-34 weeks' gestation, there was a non-statistically significant increase in survival without severe or moderate neuromotor or sensory disabilities (P=0.61), but the proportion of survivors with cerebral palsy declined (P=0.01).Conclusions In this large cohort of preterm infants, rates of survival and survival without severe or moderate neuromotor or sensory disabilities have increased during the past two decades, but these children remain at high risk of developmental delay.

Salivary Telomere Length and Lung Function in Adolescents Born Very Preterm: A Prospective Multicenter Study

Preterm birth is associated with abnormal respiratory functions throughout life. The mechanisms underlying these long-term consequences are still unclear. Shortening of telomeres was associated with many conditions, such as chronic obstructive pulmonary disease. We aimed to search for an association between telomere length and lung function in adolescents born preterm. Lung function and telomere length were measured in 236 adolescents born preterm and 38 born full-term from the longitudinal EPIPAGE cohort. Associations between telomere length and spirometric indices were tested in univariate and multivariate models accounting for confounding factors in the study population. Airflows were significantly lower in adolescents born preterm than controls; forced expiratory volume in one second was 12% lower in the extremely preterm born group than controls (p<0.001). Lower birth weight, bronchopulmonary dysplasia and postnatal sepsis were significantly associated with lower airflow values. Gender was the only factor that was significantly associated with telomere length. Telomere length correlated with forced expiratory flow 25–75 in the extremely preterm adolescent group in univariate and multivariate analyses (p = 0.01 and p = 0.02, respectively). We evidenced an association between telomere length and abnormal airflow in a population of adolescents born extremely preterm. There was no evident association with perinatal events. This suggests other involved factors, such as a continuing airway oxidative stress leading to persistent inflammation and altered lung function, ultimately increasing susceptibility to chronic obstructive pulmonary disease.

[The practices of withdrawing artificial nutrition and hydration in the neonatal intensive care unit: a preliminary study]

INTRODUCTION

Prematurity is one of the etiologies for severe neurological complications. Decisions to withdraw therapeutics, including artificial nutrition and hydration (ANH), are sometimes discussed. But can one withdraw ANH if the patient is a child suffering from severe neurological conditions, based on his best interests? The aim of this study was to further the understanding of the complexity of the withdrawal of ANH and its implementation in the neonatal intensive care unit (NICU).

METHOD

This qualitative preliminary study based on a questionnaire was conducted on the staff in the NICU of the Pontoise medical center (France) in February 2012. The results were compared with the current knowledge on this issue and sociological data.

RESULTS

Ten of the hospital staff members responded to the questionnaire: 60% considered ANH as a treatment, but the status of ANH (i.e., treatment or care) remained undefined for several respondents. Comparison with the withdrawal of mechanical ventilation or adult practices seemed to be inadequate. The staff had little experience in the domain and therefore few certainties on practices. Half of the respondents indicated that terminal sedation needed to be used. For the other half, it depended on the patient's pain. Timing was also an important notion given that the newborn is a being developing and evolving each in its own way.

CONCLUSION

The withdrawal of ANH remains controversial in the NICU. Humanity, culture, and the relationship to others are ever present in the decision-making process, creating a moral opposition above and beyond ethical reflection.

[Perinatal outcome of monochorionic and dichorionic twin gestations: a study of 775 pregnancies at Reunion Island]

OBJECTIVES

To compare the perinatal mortality and morbidity of infants born from monochorionic versus dichorionic twin pregnancies (TP).

PATIENTS AND METHODS

Retrospective, comparative study of monochorionic and dichorionic TP over 10 years in the south of Reunion Island. Information regarding demographic, gestational and perinatal variables of mothers and infants was collected from the hospital perinatal database.

RESULTS

Six hundred and twenty dichorionic and 155 monochorionic TP were analyzed. In case of monochorionic TP, mothers had higher rates of pregnancy-related hypertension (OR=1.82, 95%CI=[1.02-3.29] ; P=0.03) and hospitalization (OR=1.48, 95%CI=[1.02-2.16]; P=0.03). Newborns from monochorionic TP had higher morbidity for : very preterm birth (birth before 33 weeks gestation) (OR=1.65, 95%CI=[1.02-2.66]; P=0.02), very low birth weight (birth weight<1500g) (OR=1.73, 95%CI=[1.57-3.13]; P<0.001), Apgar<7 at 1 minute (OR=1.76, 95%CI=[1.18-2.61]; P<0.01) and hospitalization (OR=2.08, 95%CI=[1.58-2.73]; P<0.001). Perinatal mortality was also significantly higher (OR=2.47, 95%CI=[1.54-3.94]; P<0.001), as well intrauterine fetal death (OR=3.96, 95%CI=[1.95-8.05]; P<0.001) CONCLUSION: This study confirms that few differences exist among dichorionic and monochorionic TP with regard to maternal morbidity, while neonatal morbidity and mortality are higher in twins born from monochorionic pregnancies.

[Preterm birth: evolution 1994 to 2006]

OBJECTIVE

Evaluate the incidence of births before 33 weeks of amenorrhea over a 12-year period and the place of prematurity induced among them. Determine the evolution of various causes of birth prior to that and draw up a detailed inventory.

PATIENTS AND METHODS

This is a retrospective study from 1994 to 2006, concerning mothers who gave birth in the Network Users Association of computerized records in Pediatrics, Obstetrics and Gynecology (AUDIPOG) between 22 and 32+6 days of maternity. A total of 3781 deliveries were included. The statistical significance of links between the degree of prematurity (high prematurity/extreme prematurity) and the type of prematurity (induced/spontaneous) or mode of early work in the event of induced prematurity (trigger/prior cesarean work) was determined. The evolution of different etiologies was also studied with a complete inventory in 2006.

RESULTS

We observed a significant increase in the rate of births before 33 SA: it was multiplied by 3 in 12 years and stood at 1.7% of births in 2006. No increase in prematurity induced was observed, but in case of preterm labor induced the number of births by caesarean section increased significantly. Concerning the evolution of etiologies, vaginal and urinary infections decreased the most, followed by fetal malformations. Only multiple pregnancies increased significantly. The principle cause of preterm birth was hypertension. Prior to 28 SA, premature births were caused by metrorrhagia and infections at greater levels than 28-32 SA.

DISCUSSION AND CONCLUSION

The growing number of births before 33 SA is a serious phenomenon that must be monitored as they are increasingly common in France.

[Methodological aspects of economic evaluation in pediatrics: illustration by RSV infection prophylaxis in the French setting]

The methodological approach of the economic evaluation of drugs in pediatrics is illustrated by the case study of the prophylaxis for RSV infections using palivizumab in the French setting. The indications for the reimbursement of this treatment have been restricted to premature children with bronchopulmonary dysplasia (BPD) or hemodynamically significant congenital-heart disease. A model was developed primarily using the results of the pivotal clinical studies on palivizumab. Unit costs were estimated (2006 values) in both societal and payer's perspectives. An assumption was made and discussed on the benefits of the prophylaxis on mortality. Based on the different data available and the estimated costs and benefits, different cost-effectiveness ratios (CERs) were estimated from both the society's and payer's points of view. A discount rate of 3% was applied to benefit. The CER obtained in the most unfavorable case is considered acceptable for the innovative-medical technologies in the French-healthcare system. Some of the parameters used by the model will be illustrated from the EPIPAGE study data from 2 of the 9 regions involved in this study: this evaluation suggests that the children not having an RSV infection during their 1st year of life will continue to require significantly fewer hospitalizations in the following years. These additional evaluations also suggest that the model overestimates the costs of the treatment with regard to the true medical situation. This could be explained by the model not using the children's exact weight or the real number of injections because the children had been discharged from the maternity ward based on their date of birth and the epidemic period. In spite of these factors, RSV prophylaxis using palivizumab in premature children with BPD or hemodynamically significant congenital-heart disease can be considered cost-effective in France.

Behavioral outcome at 3 years of age in very preterm infants: the EPIPAGE study

OBJECTIVES

Our goal was to compare the prevalence of behavioral problems between very preterm children and term children at 3 years of age and examine the factors associated with behavioral problems in very preterm children.

METHODS

We conducted a prospective population-based cohort study: the EPIPAGE (Etude Epidémiologique sur les Petits Ages Gestationnels) study. All infants born between 22 and 32 weeks of gestation in 9 regions of France in 1997 were included and compared with a control group of infants born at term. Sociodemographic status, obstetric, and neonatal data were collected at birth and in the neonatal units. At 3 years of age, the behavioral problems of 1228 very preterm singleton children without major neurodisabilities, and 447 term children were studied using the Strengths and Difficulties Questionnaire completed by the parents.

RESULTS

Very preterm children were more likely than controls to have behavioral difficulties. Among very preterm children, several medical conditions were associated with a high total difficulty score: major neonatal cerebral lesions diagnosed by cranial ultrasonographic studies, hospitalization within the last year, poor health, and psychomotor delay. A high birth order and sociodemographic factors such as young maternal age and low educational level of the mother were also identified as risk factors for behavioral difficulties. The differences between very preterm children and controls remained significant after adjustment for sociodemographic characteristics, neonatal complications, and neurodevelopmental status, for a high total difficulties score, hyperactivity, conduct problems, and for peer problems. For emotional problems, the difference was at the limit of significance.

CONCLUSIONS

Very preterm children have a higher risk of behavioral problems at 3 years of age compared with term-born children. Health and neurodevelopmental status of the child were significantly associated with behavioral difficulties.

Réhospitalisation dans l'année suivant leur naissance des prématurés d'âge gestationnel inférieur ou égal à 32 semaines d'aménorrhée. Comparaison de 2 cohortes : 1997 et 2002

OBJECTIVE

The aim of the study was to compare the rehospitalization rate in the first year of life between 2 groups of very preterm infants born on 1997 and 2002; then we compared the very preterm infants' rehospitalization rate between our retrospective 1997 group and literature (including French cohort Epipage).

PATIENTS AND METHODS

Our retrospective study included all neonates born<or=33 GA, living in Gironde, discharged from neonatal unit at children's hospital of Bordeaux on 1997 and 2002 and rehospitalized during their first year of life.

RESULTS

Respectively 29.1% and 30.1% premature infants were rehospitalized (at least once) in 1997 and 2002 (38.2% in Epipage cohort, no statistical difference). Mean number of rehospitalizations was 1.66 in 1997 and 1.77 in 2002. Mean duration of rehospitalization was 11.8 days in 1997 and 16.8 days in 2002. These data showed no statistical difference between 1997 and 2002. Respiratory disease was the first reason of rehospitalization. Several factors were correlated with an increase risk of rehospitalization: birth weight less than 1000 g, chronic lung disease and gestational age less than 28 weeks at birth (only in 2002 cohort).

CONCLUSION

Rehospitalization rate remained stable between 1997 and 2002 whereas during this period of time, the gravity of these preterm infants had increased. The use of specific hospital discharge procedure represents a real benefit for premature infants. It must be continued after the discharge with the establishment of a strong network with the implication of parents, infants, hospital and city health workers. It may contribute to limit the very premature babies' rehospitalization rate.

[Use of medical services by very preterm children during the first year of life in the Epipage cohort]

OBJECTIVES

To compare the use of health and social services between children born before 33 weeks (very preterm), children born at 33 or 34 weeks (moderately preterm) and children born at 39 or 40 weeks (full term).

POPULATION AND METHODS

All very preterm children born in 1997 in nine French regions and a representative sample of the two other groups were followed up since birth. Data on the use of services between discharge from initial neonatal hospitalisation and the 9 months after birth were obtained by mail questionnaire filled in by parents.

RESULTS

38.2% of very preterm children, 24.3% of moderately preterm children and 10.3% of full term children were admitted to hospital at least once. Respiratory tract disorder was the main reason for rehospitalisation of very preterm children. The total number of visits, visits to specialists, and chest therapy were more frequent among very preterm children than among the two other groups.

CONCLUSION

Medical care of very preterm children is intensive after discharge from initial neonatal hospitalisation. Need of services are also substantial for moderately preterm children.

White matter damage and intraventricular hemorrhage in very preterm infants: the EPIPAGE study

OBJECTIVE

To evaluate the prevalence of cranial ultrasound abnormalities in very preterm infants as a function of gestational age, plurality, intrauterine growth restriction, and death before discharge.

STUDY DESIGN

A prospective, population-based cohort of 2667 infants born between 22 and 32 weeks of gestation in 1997 in nine regions of France, transferred to a neonatal intensive care unit, for whom at least one cranial ultrasound scan was available.

RESULTS

The frequencies of white matter damage (WMD), major WMD, cystic periventricular leukomalacia (PVL), periventricular parenchymal hemorrhagic involvement, and intraventricular hemorrhage with ventricular dilatation were 21%, 8%, 5%, 3%, and 3%, respectively. The risk of WMD increased with decreasing gestational age. Mean age at diagnosis of cystic PVL was older for the most premature infants. Intraventricular hemorrhage with ventricular dilatation was associated with a higher risk of cystic PVL. Intrauterine growth restriction was not associated with a lower prevalence of cystic PVL.

CONCLUSION

The frequency of WMD is high in very preterm babies and is strongly related to gestational age. The incidence of cystic PVL did not differ between babies with intrauterine growth restriction and babies who were appropriate for gestational age.