Severity of preterm birth and the risk of pulmonary hypertension in childhood: A population-based cohort study in Sweden.

BACKGROUND: Preterm birth (<37 completed gestational weeks) has been linked to pulmonary hypertension (PH), but the relationship to severity of preterm birth has not been studied. OBJECTIVES: We investigated associations between extremely (<28 weeks), very (28-31 weeks), moderately (32-36 weeks) preterm birth, early-term birth (37-38 weeks) and later PH. Additionally, we explored associations between birthweight for gestational age and PH. METHODS: This registry-based cohort study followed 3.1 million individuals born in Sweden (1987-2016) from 1 up to a maximum of 30 years of age. The outcome was diagnosis or death from PH in national health registers. Adjusted hazard ratios (HR) were estimated using Cox regression analysis. Unadjusted and confounder-adjusted incidence rate differences were also calculated. RESULTS: Of 3,142,812 individuals, there were 543 cases of PH (1.2 per 100,000 person-years), 153 of which in individuals without malformations. Compared with individuals born at 39 weeks, adjusted HRs with 95% confidence interval (CI) for PH for extremely, moderately, and very preterm birth were 68.78 (95% CI 49.49, 95.57), 13.86 (95% CI 9.27, 20.72) and 3.42 (95% CI 2.46, 4.74), respectively, and for early-term birth 1.74 (1.31, 2.32). HRs were higher in subjects without malformations. There were 90 additional cases of PH per 100,000 person-years in the extremely preterm group (50 after excluding malformations). Very small for gestational age (below 2 SD from estimated birthweight for gestational age and sex) was also associated with increased risk of PH (adjusted HR 2.02, 95% CI 1.14, 3.57). CONCLUSIONS: We found an inverse association between gestational age and later PH, but the incidence and absolute risks are low. The severity of preterm birth adds clinically relevant information to the assessment of cardiovascular risks in childhood.

Early N-Terminal Pro B-Type Natriuretic Peptide (NTproBNP) Plasma Values and Associations with Patent Ductus Arteriosus Closure and Treatment-An Echocardiography Study of Extremely Preterm Infants.

The aim was to investigate the association of gestational age (GA), echocardiographic markers and levels of plasma N-terminal pro-B-type natriuretic peptide (NTproBNP) with the closure rate of a haemodynamically significant patent ductus arteriosus (hsPDA). Ninety-eight Swedish extremely preterm infants, mean GA 25.7 weeks (standard deviation 1.3), born in 2012-2014, were assessed with echocardiography and for levels of NTproBNP. Thirty-three (34%) infants had spontaneous ductal closure within three weeks of age. Infants having spontaneous closure at seven days or less had significantly lower NTproBNP levels on day three, median 1810 ng/L (IQR 1760-6000 ng/L) compared with: infants closing spontaneously later, 10,900 ng/L (6120-19,200 ng/L); infants treated either with ibuprofen only, 14,600 ng/L (7740-28,100 ng/L); or surgery, 32,300 ng/L (29,100-35,000 ng/L). Infants receiving PDA surgery later had significantly higher NTproBNP values on day three than other infants. Day three NTproBNP cut-off values of 15,001-18,000 ng/L, predicted later PDA surgery, with an area under the curve in ROC analysis of 0.69 (0.54-0.83). In conclusion, the spontaneous PDA closure rate is relatively high in extremely preterm infants. Early NTproBNP levels can be used with GA in the management decisions of hsPDA.

Multi-Fetal Pregnancy, Preeclampsia, and Long-Term Cardiovascular Disease.

This Swedish register-based cohort study determined the separate and joint contribution of preeclampsia and multi-fetal pregnancy on a woman's risk of cardiovascular disease (CVD) later in life. The study included 892 425 first deliveries between 1973 and 2010 of women born 1950 until 1971, identified in the Swedish Medical Birth Register. A composite outcome of CVD was retrieved through linkage with the National Patient and Cause of Death Registers. Cox proportional hazard regression was used to assess the risk of CVD in women who had preeclampsia in a singleton or multi-fetal pregnancy, adjusting for potential confounders, and presented as adjusted hazard ratios. Compared with women who had a singleton pregnancy without preeclampsia (the referent group), women with preeclampsia in a singleton pregnancy had an increased risk of CVD (adjusted hazard ratio 1.75 [95% CI, 1.64-1.86]). Women who had a multi-fetal pregnancy without or with preeclampsia did not have an increased risk of future CVD (adjusted hazard ratios 0.94 [95% CI, 0.79-1.10] and 1.25 [95% CI, 0.83-1.86], respectively). As opposed to preeclampsia in a first singleton pregnancy, preeclampsia in a first multi-fetal pregnancy was not associated with increased risk of future CVD. This may support the theory that preeclampsia in multi-fetal pregnancies more often occurs as a result of the larger pregnancy-related burden on the maternal cardiovascular system and excessive placenta-shed inflammatory factors, rather than the woman's underlying cardiovascular phenotype.

Swedish national guideline for prevention and treatment of neonatal hypoglycaemia in newborn infants with gestational age ≥35 weeks.

AIM: Postnatal hypoglycaemia in newborn infants remains an important clinical problem where prolonged periods of hypoglycaemia are associated with poor neurodevelopmental outcome. The aim was to develop an evidence-based national guideline with the purpose to optimise prevention, diagnosis and treatment of hypoglycaemia in newborn infants with a gestational age ≥35 + 0 weeks. METHODS: A PubMed search-based literature review was used to find actual and applicable evidence for all incorporated recommendations. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach was used for grading the evidence of the recommendations. RESULTS: Recommendations for the prevention of neonatal hypoglycaemia were extended and updated, focusing on promotion of breastfeeding as one prevention strategy. Oral dextrose gel as a novel supplemental therapy was incorporated in the treatment protocol. A new threshold-based screening and treatment protocol presented as a flow chart was developed. CONCLUSION: An updated and evidence-based national guideline for screening and treatment of neonatal hypoglycaemia will support standardised regimes, which may prevent hypoglycaemia and the risk for hypoglycaemia-related long-term sequelae.

EPICE cohort: two-year neurodevelopmental outcomes after very preterm birth.

OBJECTIVE: To determine whether the variation in neurodevelopmental disability rates between populations persists after adjustment for demographic, maternal and infant characteristics for an international very preterm (VPT) birth cohort using a standardised approach to neurodevelopmental assessment at 2 years of age. DESIGN: Prospective standardised cohort study. SETTING: 15 regions in 10 European countries. PATIENTS: VPT births: 22+0-31+6 weeks of gestation. DATA COLLECTION: Standardised data collection tools relating to pregnancy, birth and neonatal care and developmental outcomes at 2 years corrected age using a validated parent completed questionnaire. MAIN OUTCOME MEASURES: Crude and standardised prevalence ratios calculated to compare rates of moderate to severe neurodevelopmental impairment between regions grouped by country using fixed effects models. RESULTS: Parent reported rates of moderate or severe neurodevelopmental impairment for the cohort were: 17.3% (ranging 10.2%-26.1% between regions grouped by country) with crude standardised prevalence ratios ranging from 0.60 to 1.53. Adjustment for population, maternal and infant factors resulted in a small reduction in the overall variation (ranging from 0.65 to 1.30). CONCLUSION: There is wide variation in the rates of moderate to severe neurodevelopmental impairment for VPT cohorts across Europe, much of which persists following adjustment for known population, maternal and infant factors. Further work is needed to investigate whether other factors including quality of care and evidence-based practice have an effect on neurodevelopmental outcomes for these children.

Traffic noise and other determinants of blood pressure in adolescence.

BACKGROUND: Exposure to traffic noise has been associated with hypertension in adults but the evidence in adolescents is limited. We investigated long-term road traffic noise exposure, maternal occupational noise during pregnancy and other factors in relation to blood pressure and prehypertension at 16 years of age. METHODS: Systolic and diastolic blood pressure were measured in 2597 adolescents from the Swedish BAMSE birth cohort. Levels of road traffic noise were estimated at home addresses during lifetime and for the mother during pregnancy as well as maternal occupational noise exposure during pregnancy. Exposure to NOx from local sources was also assessed. Associations between noise or NOx exposure and blood pressure or prehypertension were analysed using linear and logistic regression. RESULTS: The prevalence of prehypertension was higher among males and in those with overweight, low physical activity or overweight mothers. No strong or consistent associations were observed between pre- or postnatal exposure to road traffic noise and blood pressure at 16 years of age. However, inverse associations were suggested for systolic or diastolic blood pressure and prehypertension, which reached statistical significance among males (OR 0.80 per 10 dB Lden, 95% CI 0.65-0.99) and those with maternal occupational noise exposure ≥ 70 dB LAeq8h (OR 0.60, 95% CI 0.41-0.87). On the other hand, occupational noise exposure during pregnancy tended to increase systolic blood pressure and prehypertension risk in adolescence. No associations were seen for NOx exposure. CONCLUSION: No conclusive associations were observed between pre- or postnatal noise exposure and blood pressure or prehypertension in adolescents.

Postnatal nutritional intakes and hyperglycemia as determinants of blood pressure at 6.5 years of age in children born extremely preterm.

BACKGROUND: Adverse developmental programming by early-life exposures might account for higher blood pressure (BP) in children born extremely preterm. We assessed associations between nutrition, growth and hyperglycemia early in infancy, and BP at 6.5 years of age in children born extremely preterm. METHODS: Data regarding perinatal exposures including nutrition, growth and glycemia status were collected from the Extremely Preterm Infants in Sweden Study (EXPRESS), a population-based cohort including infants born <27 gestational weeks during 2004-2007. BP measurements were performed at 6.5 years of age in a sub-cohort of 171 children (35% of the surviving children). RESULTS: Higher mean daily protein intake (+1 g/kg/day) during postnatal weeks 1-8 was associated with 0.40 (±0.18) SD higher diastolic BP. Higher mean daily carbohydrate intake (+1 g/kg/day) during the same period was associated with 0.18 (±0.05) and 0.14 (±0.04) SD higher systolic and diastolic BP, respectively. No associations were found between infant growth (weight, length) and later BP. Hyperglycemia and its duration during postnatal weeks 1-4 were associated primarily with higher diastolic BP z-scores. CONCLUSIONS: These findings emphasize the importance of modifiable early-life exposures, such as nutrition and hyperglycemia, in determining long-term outcomes in children born extremely preterm.

Maternal Overweight and Obesity and Risk of Congenital Heart Defects.

BACKGROUND: Congenital heart defects are more frequent in offspring of mothers with overweight or obesity. However, associations between maternal overweight and obesity, and risks of complex and specific heart defects are not clear. OBJECTIVES: This study sought to analyze associations between maternal overweight and obesity severity and rates of complex and specific heart defects. METHODS: This was a population-based cohort study in Sweden, including 2,050,491 live singleton infants born between 1992 and 2012. Data on maternal and infant characteristics, and diagnoses of congenital heart defects were retrieved from nationwide registries. Maternal body mass index (BMI) was categorized as underweight (BMI <18.5 kg/m2), normal weight (BMI 18.5 to <25 kg/m2), overweight (BMI 25 to <30 kg/m2), obesity class I (BMI 30 to <35 kg/m2), class II (BMI 35 to <40 kg/m2), and class III (BMI ≥40 kg/m2). Outcomes included complex heart defects (tetralogy of Fallot, transposition of the great arteries, atrial septal defects [ASD], aortic arch defects, and single-ventricle heart) and subgroups of specific heart defects diagnosed up to 5 years of age. The authors calculated adjusted prevalence rate ratios (PRRs) with 95% confidence intervals. RESULTS: A total of 28,628 (1.40%, N = 2,050,491) children had at least 1 congenital heart defect. PRRs of aortic arch defects increased with maternal obesity severity. Compared with offspring of normal weight mothers, PRRs of aortic arch defects and transposition of the great arteries were doubled in offspring of mothers with severe obesity. PRRs of ASD and persistent ductus arteriosus in term infants increased with maternal BMI. CONCLUSIONS: PRRs of aortic branch defects, ASD, and persistent ductus arteriosus increase with maternal obesity severity.

Wide variation in severe neonatal morbidity among very preterm infants in European regions.

OBJECTIVE: To investigate the variation in severe neonatal morbidity among very preterm (VPT) infants across European regions and whether morbidity rates are higher in regions with low compared with high mortality rates. DESIGN: Area-based cohort study of all births before 32 weeks of gestational age. SETTING: 16 regions in 11 European countries in 2011/2012. PATIENTS: Survivors to discharge from neonatal care (n=6422). MAIN OUTCOME MEASURES: Severe neonatal morbidity was defined as intraventricular haemorrhage grades III and IV, cystic periventricular leukomalacia, surgical necrotizing enterocolitis and retinopathy of prematurity grades ≥3. A secondary outcome included severe bronchopulmonary dysplasia (BPD), data available in 14 regions. Common definitions for neonatal morbidities were established before data abstraction from medical records. Regional severe neonatal morbidity rates were correlated with regional in-hospital mortality rates for live births after adjustment on maternal and neonatal characteristics. RESULTS: 10.6% of survivors had a severe neonatal morbidity without severe BPD (regional range 6.4%-23.5%) and 13.8% including severe BPD (regional range 10.0%-23.5%). Adjusted inhospital mortality was 13.7% (regional range 8.4%-18.8%). Differences between regions remained significant after consideration of maternal and neonatal characteristics (P<0.001) and severe neonatal morbidity rates were not correlated with mortality rates (P=0.50). CONCLUSION: Severe neonatal morbidity rates for VPT survivors varied widely across European regions and were independent of mortality rates.

Early energy and protein intakes and associations with growth, BPD, and ROP in extremely preterm infants.

BACKGROUND & AIM: Extremely preterm infants face substantial neonatal morbidity. Nutrition is important to promote optimal growth and organ development in order to reduce late neonatal complications. The aim of this study was to examine the associations of early nutritional intakes on growth and risks of bronchopulmonary dysplasia (BPD) and retinopathy of prematurity (ROP) in a high-risk population. METHODS: This population-based cohort study includes infants born before 27 0/7 weeks of gestational age without severe malformations and surviving ≥10 days. Intake of energy and protein on postnatal days 4-6 and association with weight standard deviation score (WSDS) from birth to day 7, as well as intakes of energy and protein on postnatal days 4-6 and 7 to 27, respectively, and association with composite outcome of death and BPD and separate outcomes of BPD and ROP were examined, and adjusted for potential confounders. RESULTS: The cohort comprised 296 infants with a median gestational age of 25 3/7 weeks. Expressed as daily intakes, every additional 10 kcal/kg/d of energy during days 4-6 was associated with 0.08 higher WSDS on day 7 (95% CI 0.06-0.11; p < 0.001). Between days 7 and 27, every 10 kcal/kg/d increase in energy intake was associated with a reduced risk of BPD of 9% (95% CI 1-16; p = 0.029) and any grade of ROP with a reduced risk of 6% (95% CI 2-9; p = 0.005) in multivariable models. This association was statistically significant in infants with ≤10 days of mechanical ventilation. In infants with >10 days of mechanical ventilation, a combined higher intake of energy and protein was associated with a reduced risk of BPD. CONCLUSION: Early provision of energy and protein may reduce postnatal weight loss and risk of morbidity in extremely preterm infants.

Specialist health care services use in a European cohort of infants born very preterm.

AIM: Children born very preterm require additional specialist care because of the health and developmental risks associated with preterm birth, but information on their health service use is sparse. We sought to describe the use of specialist services by children born very preterm in Europe. METHOD: We analysed data from the multi-regional, population-based Effective Perinatal Intensive Care in Europe (EPICE) cohort of births before 32 weeks' gestation in 11 European countries. Perinatal data were abstracted from medical records and parents completed a questionnaire at 2 years corrected age (4322 children; 2026 females, 2296 males; median gestational age 29wks, interquartile range [IQR] 27-31wks; median birthweight 1230g, IQR 970-1511g). We compared parent-reported use of specialist services by country, perinatal risk (based on gestational age, small for gestational age, and neonatal morbidities), maternal education, and birthplace. RESULTS: Seventy-six per cent of the children had consulted at least one specialist, ranging across countries from 53.7% to 100%. Ophthalmologists (53.4%) and physiotherapists (48.0%) were most frequently consulted, but individual specialists varied greatly by country. Perinatal risk was associated with specialist use, but the gradient differed across countries. Children with more educated mothers had higher proportions of specialist use in three countries. INTERPRETATION: Large variations in the use of specialist services across Europe were not explained by perinatal risk and raise questions about the strengths and limits of existing models of care. WHAT THIS PAPER ADDS: Use of specialist services by children born very preterm varied across Europe. This variation was observed for types and number of specialists consulted. Perinatal risk was associated with specialist care, but did not explain country-level differences. In some countries, mothers' educational level affected use of specialist services.

UTILIZACIÓN DE SERVICIOS DE SALUD ESPECIALIZADOS EN UN ESTUDIO DE COHORTE EUROPEO DE NIÑOS NACIDOS MUY PREMATUROS: OBJETIVO: Niños nacidos muy prematuramente requieren cuidados especializados adicionales debido a su salud y a los riesgos asociados con la prematuros, sin embargo la información sobre el uso de servicios de salud es escasa. Buscamos describir la utilización de servicios especializados por niños nacidos muy prematuramente, en Europa. MÉTODO: Analizamos datos de una cohorte de nacimientos ocurridos antes de las 32 semanas de gestación tomados del Effective Perinatal Intensive Care in Europe (EPICE), basado en la población y multirregional, en 11 países europeos. Los datos perinatales fueron extraídos de las historias clínicas y los padres completaron un cuestionario a los 2 años de edad corregida (4.322 niños; 2026 sexo femenino, 2.296 masculino; edad gestacional mediana 29 semanas, rango intercuartílico (IQR) 27-31 semanas; mediana de peso de nacimiento 1.230 gr, IQR 970-1.511 gr). Comparamos el uso de servicios especializados (según informe de los padres) por país, riesgo perinatal (basado en edad gestacional, bajo peso para edad gestacional y morbilidades neonatales), educación materna y lugar de nacimiento. RESULTADOS: En total 65% de los niños habían consultado por lo menos a un especialista, con un rango entre países de 53,7% a 100%. Los especialistas más frecuentemente consultados fueron Oftalmólogos (53,4%) y Fisioterapeutas (48%) pero los especialistas consultados por cada individuo variaron mucho según el país. El riesgo perinatal se asoció al uso de especialista, pero el gradiente varió entre los países. Niños de madres con mayor nivel educativo tuvieron mayor proporción de uso de especialistas en tres países. INTERPRETACIÓN: Las grandes variaciones en el uso de servicios especializados en Europa no fueron explicadas por el riesgo perinatal y arrojan cuestionamientos sobre las fortalezas y limitaciones de los modelos de cuidados existentes.

USO DE SERVIÇOS DE SAÚDE ESPECIALIZADOS EM UMA COORTE EUROPÉIA DE LACTENTES NASCIDOS MUITO PREMATUROS: OBJETIVO: Crianças nascidas muito prematuras requerem cuidado especializado adicional por causa dos riscos à saúde e ao desenvolvimento associados ao nascimento premature, mas informações sobreo uso de serviços de saúde são escassas. Procuramos descrever o uso de serviços especializados por crianças nascidas muito prematuras na Europa. MÉTODO: Analisamos dados de uma coorte populacional multi-regional, do Cuidado Intensivo Neonatal Efetivo na Europa (EPICE), com lactentes nascidos antes de 32 semanas de gestação em 11 países europeus. Dados perinatais foram extraídos dos registros médicos, e os pais completaram um questionário com 2 anos de idade corrigida (4.322 crianças; 2.026 do sexo feminino, 2.296 do sexo masculino; idade gestacional mediana 29semanas, intervalo interquartile [IIQ] 27-31sem; peso ao nascimento mediano 1,230g, IIQ 970-1511g). Comparamos o uso de serviços especializados reportados pelos pais por país, risco perinatal (com base na idade gestacional, pequeno para a idade gestacional e morbidades neonatais), educação materna e local de nascimento. RESULTADOS: Setenta e seis por cento das crianças consultou pelo menos um especialista, variando entre países de 53,7 a 100%. Oftalmologistas (53,4%) e fisioterapeutas (48,0%) foram os mais frequentemente consultados, mas os especialistas individuais variaram bastante por país. O risco perinatal se associou com uso de serviços especializados, mas o gradient diferiu entre países. Crianças com mães mais educadas tinham maior proporção de uso de especialistas em três países. INTERPRETAÇÃO: Grandes variações no uso de serviços especializados na Europa não foram explicadas pelo risco perinatal, e levantam questões sobre as forças e limitações dos modelos de cuidado existentes.

Snus users had high levels of nicotine, cotinine and 3-hydroxycotinine in their breastmilk, and the clearance was slower than in smoking mothers.

AIM: Using snus, an oral moist tobacco, has increased among pregnant women in Sweden, the only European Union country where sales are legal. This study evaluated whether snus generated similar concentrations of nicotine and its metabolites in breastmilk to cigarette smoking. METHODS: We analysed 49 breastmilk samples from 33 nursing mother - 13 snus users, six cigarette smokers and 14 controls - for concentrations of nicotine, cotinine and 3-hydroxycotinine. The mothers were recruited at antenatal clinics in Sweden from 2007 to 2012. RESULTS: The median nicotine concentration in breastmilk of the snus users was 38.7 ng/mL (0-137) versus 24.0 ng/mL (0-56) in smokers, with median cotinine levels of 327.6 ng/mL (37-958) versus 164.4 ng/mL and median 3-hydroxycotinine levels of 202.7 ng/mL (28-452) versus 112.4 (0-231), respectively. Nicotine was still detected in the breastmilk of eight of the 13 snus users after abstaining from tobacco for a median duration of 11 hours (0.6-12.5), while the breastmilk of the smokers was nicotine-free after four hours' abstinence. CONCLUSION: Snus users had high levels of nicotine and metabolites in their breastmilk and nicotine was found even after 12.5 hours of abstinence.

Maternal snuff use and cotinine in late pregnancy-A validation study.

INTRODUCTION: Oral moist snuff is widely used in Sweden including during pregnancy. Maternal snuff use has been associated with increased risks of adverse pregnancy outcomes in epidemiological studies. Self-reported maternal snuff use has not been validated previously. The main objective of this study was to validate self-reported snuff use in pregnancy in a prospective cohort study and in the Medical Birth Register. MATERIAL AND METHODS: A prospective Swedish cohort study, 2005-2011, in which 572 women were asked to participate. Of 474 recruited women, 381 non-smokers (263 snuff users and 118 non-tobacco users) were included in the main analyses. Participants prospectively reported snuff use through questionnaires. Medical Birth Register data on the participants was obtained. Maternal urine cotinine was collected in late pregnancy and was used as a biomarker. RESULTS: Cotinine levels in maternal urine confirmed a high validity of self-reported snuff use through questionnaires in late pregnancy; sensitivity and specificity values were 98% and 96%, respectively. In the Medical Birth Register, 45% of the snuff users were misclassified as nonusers in late pregnancy. There were significant differences in median cotinine levels between users of mini pouches and users of standard pouches, but there was a great difference of cotinine levels among users with similar number of pouches used daily. CONCLUSIONS: Self-reported snuff use through questionnaires has high validity. In the Medical Birth Register, in late pregnancy, many snuff users were misclassified as nonusers. As a consequence, there is a risk of underestimating the harmful effects of snuff use when using late pregnancy Medical Birth Register data.

Cohort study from 11 European countries highlighted differences in the use and efficacy of hypothermia prevention strategies after very preterm birth.

AIM: This study investigated the different strategies used in 11 European countries to prevent hypothermia, which continues to affect a large proportion of preterm births in the region. METHODS: We examined the association between the reported use of hypothermia prevention strategies in delivery rooms and body temperatures on admission to neonatal intensive care units (NICUs) in 5861 infants born at 22 + 0 to 31 +6 weeks of gestation. The use of plastic bags, wraps, caps, exothermic heat and mattresses was investigated. RESULTS: The proportion of infants born in units that systematically used one or more hypothermia prevention strategies was 88.2% and 50.9% of those infants were hypothermic on admission to NICUs. Of the 9.6% born in units without systematic hypothermia prevention, 73.2% were hypothermic. Only 2.2% of infants were born in units with no reported prevention strategies. Lower gestational age increased the probability of hypothermia. No significant differences were found between the various hypothermia prevention strategies. Hyperthermia was seen in 4.8% of all admitted infants. CONCLUSION: Very preterm infants had lower risks of hypothermia on NICU admission if the unit used systematic prevention strategies. All the strategies had similar effects, possibly due to implementation rather than a strategy's specific efficacy.

Room for improvement in breast milk feeding after very preterm birth in Europe: Results from the EPICE cohort.

Breast milk feeding (BMF) is associated with lower neonatal morbidity in the very preterm infant (<32 weeks gestation) and breastfeeding is beneficial for maternal health. Previous studies show large variations in BMF after very preterm birth and recognize the need for targeted breastfeeding support in the neonatal intensive care units (NICU). In a European collaboration project about evidence-based practices after very preterm birth, we examined the association between maternal, obstetric, and infant clinical factors; neonatal and maternal care unit policies; and BMF at discharge from the NICU. In multivariable analyses, covariates associated with feeding at discharge were first investigated as predictors of any BMF and in further analysis as predictors of exclusive or partial BMF. Overall, 58% (3,826/6,592) of the infants received any BMF at discharge, but there were large variations between regions (range 36-80%). Primiparity, administration of antenatal corticosteroids, first enteral feed <24 hr after birth, and mother's own milk at first enteral feed were predictors positively associated with any BMF at discharge. Vaginal delivery, singleton birth, and receiving mother's own milk at first enteral feed were associated with exclusive BMF at discharge. Units with a Baby Friendly Hospital accreditation improved any BMF at discharge; units with protocols for BMF and units using donor milk had higher rates of exclusive BMF at discharge. This study suggests that there is a high potential for improving BMF through policies and support in the NICU.

Blood Pressure in 6-Year-Old Children Born Extremely Preterm.

BACKGROUND: Advances in perinatal medicine have increased infant survival after very preterm birth. Although this progress is welcome, there is increasing concern that preterm birth is an emerging risk factor for hypertension at young age, with implications for the lifetime risk of cardiovascular disease. METHODS AND RESULTS: We measured casual blood pressures (BPs) in a population-based cohort of 6-year-old survivors of extremely preterm birth (<27 gestational weeks; n=171) and in age- and sex-matched controls born at term (n=172). Measured BP did not differ, but sex, age-, and height-adjusted median z scores were 0.14 SD higher (P=0.02) for systolic BP and 0.10 SD higher (P=0.01) for diastolic BP in children born extremely preterm than in controls. Among children born extremely preterm, shorter gestation, higher body mass index, and higher heart rate at follow-up were all independently associated with higher BP at 6 years of age, whereas preeclampsia, smoking in pregnancy, neonatal morbidity, and perinatal corticosteroid therapy were not. In multivariate regression analyses, systolic BP decreased by 0.10 SD (P=0.08) and diastolic BP by 0.09 SD (P=0.02) for each week-longer gestation. CONCLUSIONS: Six-year-old children born extremely preterm have normal but slightly higher BP than their peers born at term. Although this finding is reassuring for children born preterm and their families, follow-up at older age is warranted.

Preterm Birth and Risk of Heart Failure Up to Early Adulthood.

BACKGROUND: In small clinical studies, preterm birth was associated with altered cardiac structure and increased cardiovascular mortality in the young. OBJECTIVES: The goal of this study was to determine the association between preterm birth and risk of incident heart failure (HF) in children and young adults. METHODS: This register-based cohort study included 2,665,542 individuals born in Sweden from 1987 to 2012 who were followed up from 1 year of age to December 31, 2013. The main study outcome was diagnosis of HF in the National Patient Register or the Cause of Death Register. The association between preterm birth and risk of incident HF was analyzed by using a Poisson regression model. Estimates were adjusted for maternal and pregnancy characteristics, socioeconomic status, and maternal and paternal cardiovascular disease. RESULTS: During 34.8 million person-years of follow-up (median 13.1 years), there were 501 cases of HF. After exclusion of 52,512 individuals with malformations (n = 196 cases), 305 cases of HF remained (0.88 per 100,000 person-years). Gestational age was inversely associated with the risk of HF. Compared with individuals born at term (≥37 weeks' gestation), adjusted incidence relative risks for HF were 17.0 (95% confidence interval [CI]: 7.96 to 36.3) after extremely preterm birth (<28 weeks) and 3.58 (95% CI: 1.57 to 8.14) after very preterm birth (28 to 31 weeks). There was no risk increase after moderately preterm birth (32 to 36 weeks) (relative risk: 1.36; 95% CI: 0.87 to 2.13). CONCLUSIONS: There was a strong association between preterm birth before 32 weeks of gestation and HF in childhood and young adulthood. Although the absolute risk of HF is low in young age, our findings indicate that preterm birth may be a previously unknown risk factor for HF.

Preterm arteries in childhood: dimensions, intima-media thickness, and elasticity of the aorta, coronaries, and carotids in 6-y-old children born extremely preterm.

BACKGROUND: Preterm birth increases risk for adult cardiovascular disease. We hypothesized that arteries in 6-y-old children born preterm are narrower, with thicker intima-media and stiffer than in peers born at term. METHODS: Children born extremely preterm (EXP, n = 176, birthweights: 348-1,161 g) and at term (CTRL, n = 174, birthweights: 2,430-4,315 g) were included. Using ultrasonography, we determined diameters of the coronaries (CA), common carotid arteries (CCA) and aorta, the carotid intima media thickness (cIMT), and the stiffness index of the CCA and aorta. RESULTS: Arteries were 5-10% narrower in EXP than in CTRL (P < 0.005) but after adjustment for body surface area, diameter differences diminished or disappeared. EXP-children born small for gestational age exhibited similar arterial dimensions as those born appropriate for date. The cIMT was 0.38 (SD = 0.04) mm and did not differ between groups. Carotid but not aortic stiffness was lower in EXP than in CTRL. CONCLUSION: In 6-y-old children born extremely preterm, conduit arteries are of similar or smaller size than in controls born at term, and they have no signs of accelerated intima media thickening or arterial stiffening. While these findings are reassuring for these children and their families, the causal pathways from preterm birth to adult cardiovascular disease remain unknown.