Health of very low birth weight children during their first eight years

Need for Repeat-Hospitalization in Very Low Birth Weight or Very Preterm Infants: A Prospective Cohort Study

OBJECTIVE

To determine the incidence of repeat-hospitalization amongst neonates with gestation <32 wk or birth weight <1500 g within 6 mo of birth.

METHODS

All live births with gestation <32 wk or birth weight <1500 g born at a level-III NICU were prospectively enrolled and followed up through routine visits, multimedia and telephonically, fortnightly for re-hospitalization details till 6 mo of postnatal age. Main outcome measures were incidence, causes and risk factors for repeat-hospitalization.

RESULTS

Of the 131 neonates enrolled, incidence and incidence density of repeat-hospitalization were 16% (95% CI 10.2-23.4) and 3.6 per 100 person-months, respectively. The most common causes for repeat-hospitalizations were pneumonia (n = 8; 29.6%), sepsis (n = 5, 18.5%), gastroenteritis (n = 3, 11.1%) and severe anemia (n = 2, 7.4%). Majority of repeat-hospitalizations (92.6%; 95% CI 74.1-98.5) occurred within 2 mo of discharge. The median hospital stay during repeat-hospitalizations was 4 d (IQR 1-21). On multivariate analysis, lower socioeconomic status was significantly associated with repeat-hospitalization (aOR 5.9, 1.3-23). Death after discharge occurred in 3 (2.3%) infants and were due to sudden infant death syndrome, complex cyanotic heart disease and pneumonia with multiple co-morbidities (one each). All deaths occurred at home.

CONCLUSIONS

Nearly one-sixth of very low birth weight (VLBW) or very preterm infants required repeat-hospitalization after discharge, primarily within 2 mo of discharge. Infections, especially pneumonia, being the most common reason. A comprehensive follow-up package of post-discharge care for prevention of morbidities and timely hospital care for ongoing morbidities is required for optimal long-term survival of these infants.

Type of Re-Hospitalization and Association with Neonatal Morbidities in Infants of Very Low Birth Weight

BACKGROUND

Preterm infants are at high risk for long-term morbidities and an increased rate of re-hospitalization.

OBJECTIVE

The aim of this study was to evaluate the type of re-hospitalization of very low birth weight (VLBW) infants, from infancy through adolescence, and to assess the association of neonatal morbidities with specific types of re-hospitalization.

STUDY DESIGN

The study cohort comprised 6,385 VLBW infants who were registered with the Maccabi Healthcare Services (MHS) from their birth hospitalization. Data were collected for up to 18 years (median 10.7 years) following neonatal intensive care unit discharge. Hospitalization types were determined from the MHS coding. Neonatal morbidities included necrotizing enterocolitis (NEC), grades 3-4 intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP). Adjusted hazard ratios (aHR) and 95% confidence intervals (CI) were calculated using the Cox proportional hazards model.

RESULTS

Overall, 3,956 infants were re-hospitalized at least once and a total of 11,595 hospitalization types were identified. NEC, IVH, PVL, and BPD were associated with significantly higher aHRs for general pediatric (aHR 1.28-1.55), general surgical (aHR 1.18-1.46), and pediatric intensive care unit (aHR 1.57-2.04) hospitalizations. IVH and PVL were associated with significantly higher aHRs for orthopedic (aHR 2.12 and 4.88, respectively) and ophthalmology (1.76 and 4.02, respectively) hospitalizations. IVH was associated with a 14.2-fold higher aHR for neurosurgical admissions, and ROP with a 1.62-fold higher aHR for ophthalmology hospitalizations.

CONCLUSION

Among VLBW infants, specific patterns of re-hospitalization types associated with major neonatal morbidities were identified as particularly high risks for orthopedic and ophthalmology hospitalizations in infants with IVH and PVL, and for intensive care admissions in infants with NEC and BPD.

Increasing Incidence of Infants with Low Birth Weight in Oman

This review article provides an overview of the levels, trends and some possible explanations for the increasing rate of low birth weight (LBW) infants in Oman. LBW data from national health surveys in Oman, and published reports from Oman's Ministry of Health and the World Health Organization were collected and assessed between January and August 2014. Oman's LBW rate has been increasing since the 1980s. It was approximately 4% in 1980 and had nearly doubled (8.1%) by 2000. Since then, it has shown a slow but steady rise, reaching 10% in recent times. High rates of consanguinity, premature births, number of increased pregnancies at an older maternal age and changing lifestyles are some important factors related to the increasing rate of LBW in Oman. The underlying causes of this increase need to be understood and addressed in obstetric policies and practices in order to reduce the rate of LBW in Oman.

Neonatal hyperoxia leads to persistent alterations in NK responses to influenza A virus infection

Respiratory distress in preterm or low birth weight infants is often treated with supplemental oxygen. However, this therapy can disrupt normal lung development and architecture and alter responses to respiratory insults. Similarly, exposure of newborn mice to 100% oxygen during saccular lung development leads to permanent alveolar simplification, and upon challenge with influenza A virus, mice exhibit reduced host resistance. Natural killer (NK) cells are key players in antiviral immunity, and emerging evidence suggest they also help to maintain homeostasis in peripheral tissues, including the lung, by promoting epithelial cell regeneration via IL-22. We tested the hypothesis that adult mice exposed to hyperoxia as neonates have modified NK cell responses to infection. We report here that mice exposed to neonatal hyperoxia had fewer IL-22(+) NK cells in their lungs after influenza virus challenge and a parallel increase in IFN-γ(+) NK cells. Using reciprocal bone marrow chimeric mice, we show that exposure of either hematopoietic or nonhematopoietic cells was sufficient to increase the severity of infection and to diminish the frequency of IL-22(+) NK cells in the infected lung. Overall, our findings suggest that neonatal hyperoxia leads to long-term changes in the reparative vs. cytotoxic nature of NK cells and that this is due in part to intrinsic changes in hematopoietic cells. These differences may contribute to how oxygen alters the host response to respiratory viral infections.

Readmission of Preterm Infants Less Than 32 Weeks Gestation Into Early Childhood: Does Gender Difference Still Play a Role?

The aim of the study was to investigate the frequency of and the predictors for rehospitalization in preterm infants into early childhood, focusing on gender differences. All preterm infants born at <32 weeks of gestation in North Tyrol between January 2003 and December 2005 were enrolled in this survey. About one fifth of all children were readmitted, showing an inverse downward trend with increasing age. The most common reason for readmission in the third (36.5%) and fourth (42.9%) years of life was respiratory infection, but changed to miscellaneous surgeries in the fifth (52.1%). Male sex showed significantly higher readmission rates and more miscellaneous surgeries. Additionally, male sex and chronic lung disease were risk conditions for rehospitalization in the multivariate analysis. Readmission rates and respiratory infections in preterm-born children showed an inverse downward trend with increasing age. In early childhood, gender difference still plays a role with regard to rehospitalization.

Perinatal and socioeconomic risk factors for variable and persistent cognitive delay at 24 and 48 months of age in a national sample

The objective of this paper is to examine patterns of cognitive delay at 24 and 48 months and quantify the effects of perinatal and sociodemographic risk factors on persistent and variable cognitive delay. Using data from 7,200 children in the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), multiple logistic regression models identified significant predictors of low cognitive functioning at 24 and 48 months. Additional multiple logistic models predicting cognitive delay at 48 months were estimated separately for children with and without delay at 24 months. Of the nearly 1,000 children delayed at 24 months, 24.2% remained delayed by 48 months; 7.9% of the children not delayed at 24 months exhibited delay at 48 months. Low and very low birthweight increased cognitive delay risk at 24, but not 48 months. Low maternal education had a strongly increasing effect (OR = 2.3 at 24 months, OR = 13.7 at 48 months), as did low family income (OR = 1.4 at 24 months, OR = 7.0 at 48 months). Among children delayed at 24 months, low maternal education predicted delay even more strongly at 48 months (OR = 30.5). Low cognitive functioning is highly dynamic from 24 to 48 months. Although gestational factors including low birthweight increase children’s risk of cognitive delay at 24 months, low maternal education and family income are more prevalent in the pediatric population and are much stronger predictors of both persistent and emerging delay between ages 24 and 48 months.

Rehospitalization in the first 2 years of life in children born preterm

AIM

Aim of the study is to investigate the frequency of and predictors for rehospitalization within the first 2 years of life among preterm infants.

METHODS

All children born before 32 weeks of gestation in Northern Tyrol between January 2003 and July 2008 were prospectively enrolled. Data on rehospitalizations were obtained from hospital admission records. The association between candidate risk factors and readmission was analysed by means of logistic regression analysis.

RESULTS

In the first and second years of life, 151 and 93 of 377 children (40.1% and 24.7%), respectively, were readmitted to one of the hospitals in Northern Tyrol. The most common causes of rehospitalization were respiratory disorders, accounting for 42.1% and 47.4% of total readmissions in the first and second years of life. Chronic lung disease (CLD), male sex and smoking in pregnancy were risk conditions relevant to readmission in the first year of life, but only CLD in the second year.

CONCLUSION

Infants born before 32 weeks of gestation have a high risk of rehospitalization with respiratory illness significantly contributing to postdischarge morbidity. Neonatal intensive care should aim to further improve respiratory health in preterm infants, and adequate follow-up services must be offered.

Preterm infants fed nutrient-enriched formula until 6 months show improved growth and development

BACKGROUND

The purpose of the present study was to determine the effect of feeding nutrient-enriched preterm formula to preterm infants until 6 months' corrected age (CA) on growth and development in the first 18 months of life.

METHODS

Very low-birthweight preterm infants were fed preterm formula until term (40 weeks CA). Infants were then assigned to one of three groups and were fed term formula until 6 months' CA (group 1, n= 29); preterm formula to 3 months' CA and then term formula to 6 months' CA (group 2, n= 30); or preterm formula until 6 months' CA (group 3, n= 31). Anthropometry was performed at term, 3, 6, 9, 12, 15, and at s18 months' CA. Mental and psychomotor development were assessed using the Bayley Scales of Infant Development II at 18 months' CA.

RESULTS

Although body weight, length, head circumference and z score for CA at term in group 3 were significantly lower than those of groups 1 and 2, growth rates of these parameters were significantly higher in group 3 up to 18 months CA', as compared to groups 1 and 2. The mental developmental index and psychomotor developmental index of the Bayley test were not significantly different between the three groups.

CONCLUSIONS

Very low-birthweight preterm infants fed nutrient-enriched preterm formula until 6 months' CA demonstrated significantly improved growth rates for bodyweight, length and head circumference, and comparable mental and psychomotor development throughout the first 18 months of life.

Can recall of birth size be used as a measure of birthweight in Cameroon?

Birthweight is a key predictor of future life outcomes. When this information is not available we must rely on maternal recall of weight or size. We evaluated the use of maternal recall of size as an indicator for birthweight, using data from the 2004 Demographic and Health Survey in Cameroon. The overall agreement between recorded and recalled weight and subjective assessment of birth size was 90% (Kappa = 0.46). Concordant descriptions were associated with higher birthweights (P < 0.001), higher education (P = 0.008) and delivery in a health unit (P = 0.025). Specificity for low birthweight (92.9%) was much higher than sensitivity (59.9%) and the negative predictive value (96.1%) was much higher than the positive predictive value (44.4%). These results indicate that recall of size, in Cameroonian women and in other low resource settings, should be used only in the absence of other sources of data.

Hypoglycemia and the origin of hypoxia-induced reduction in human fetal growth

BACKGROUND

The most well known reproductive consequence of residence at high altitude (HA >2700 m) is reduction in fetal growth. Reduced fetoplacental oxygenation is an underlying cause of pregnancy pathologies, including intrauterine growth restriction and preeclampsia, which are more common at HA. Therefore, altitude is a natural experimental model to study the etiology of pregnancy pathophysiologies. We have shown that the proximate cause of decreased fetal growth is not reduced oxygen availability, delivery, or consumption. We therefore asked whether glucose, the primary substrate for fetal growth, might be decreased and/or whether altered fetoplacental glucose metabolism might account for reduced fetal growth at HA.

METHODS

Doppler and ultrasound were used to measure maternal uterine and fetal umbilical blood flows in 69 and 58 residents of 400 vs 3600 m. Arterial and venous blood samples from mother and fetus were collected at elective cesarean delivery and analyzed for glucose, lactate and insulin. Maternal delivery and fetal uptakes for oxygen and glucose were calculated.

PRINCIPAL FINDINGS

The maternal arterial - venous glucose concentration difference was greater at HA. However, umbilical venous and arterial glucose concentrations were markedly decreased, resulting in lower glucose delivery at 3600 m. Fetal glucose consumption was reduced by >28%, but strongly correlated with glucose delivery, highlighting the relevance of glucose concentration to fetal uptake. At altitude, fetal lactate levels were increased, insulin concentrations decreased, and the expression of GLUT1 glucose transporter protein in the placental basal membrane was reduced.

CONCLUSION/SIGNIFICANCE

Our results support that preferential anaerobic consumption of glucose by the placenta at high altitude spares oxygen for fetal use, but limits glucose availability for fetal growth. Thus reduced fetal growth at high altitude is associated with fetal hypoglycemia, hypoinsulinemia and a trend towards lactacidemia. Our data support that placentally-mediated reduction in glucose transport is an initiating factor for reduced fetal growth under conditions of chronic hypoxemia.

Fatores associados à morbidade respiratória entre 12 e 36 meses de vida de crianças nascidas de muito baixo peso oriundas de uma UTI neonatal pública

O objetivo do estudo foi estimar a morbidade respiratória entre 12 e 36 meses em crianças prematuras e identificar os fatores associados. A população compreendeu 84 crianças de uma coorte de prematuros de muito baixo peso. O desfecho foi a taxa de incidência de morbidade respiratória. A associação entre as variáveis independentes e morbidade respiratória foi verificada por modelo linear generalizado. Entre 12 e 24 meses, 56,3% das crianças apresentaram morbidade respiratória. Entre 24 e 36 meses, 38,1% das crianças foram acometidas. As variáveis associadas à morbidade respiratória foram: displasia broncopulmonar (RT = 1,9; IC95%: 1,2-2,9), complacência pulmonar alterada (RT = 1,6; IC95%: 1,1-2,2), pneumonia neonatal (RT = 2,8; IC95%: 2,0-4,0), persistência do canal arterial (RT = 1,6; IC95%: 1,1-2,4) e morbidade respiratória no primeiro ano de vida (RT = 1,8; IC95%: 1,3-2,6). A incidência de morbidade respiratória entre 12 e 36 meses se manteve elevada neste grupo de crianças de alto risco, o que reforça a necessidade de acompanhamento e de intervenções efetivas na prevenção do adoecimento e na melhora da qualidade de vida destas crianças e suas famílias.

Parental and perinatal factors affecting childhood anthropometry of very-low-birth-weight premature infants: a population-based survey

BACKGROUND

The perinatal-neonatal course of very-low-birth-weight (VLBW) infants might affect their childhood growth. We evaluated the effect of parental anthropometry and perinatal and neonatal morbidity of VLBW neonates on their childhood growth.

METHODS

We obtained parental anthropometry, height and weight at age 6-10.5 years of 334 children born as VLBW infants. Parental, perinatal and neonatal data of these children were tested for association with childhood anthropometry.

RESULTS

(1) Maternal and paternal weight standard deviation score (SDS) and discharge weight (DW) SDS were associated with childhood weight SDS (R(2)= 0.111, p < 0.00001); (2) Maternal and paternal height SDS, corrected gestational age (GA) at discharge, maternal assisted reproduction and SGA status were associated with childhood height SDS (R(2)= 0.208, p < 0.00001); (3) paternal weight SDS, DW SDS and surfactant therapy were associated with childhood body mass index (BMI) SDS (R(2)= 0.096, p < 0.00001). 31.1% of VLBW infants had DW SDS < -1.88, and are to be considered small for gestational age ('SGA'). One quarter of these infants did not catch up by age 6-10.5 years.

CONCLUSION

Childhood anthropometry of VLBW infants depends on parental anthropometry, postnatal respiratory morbidity and growth parameters at birth and at discharge. Almost one-third of VLBW premature infants had growth restriction at discharge from neonatal intensive care unit (NICU), a quarter of whom did not catch up by age 6-10.5 years.

Self-perceived health, functioning and well-being of very low birth weight infants at age 20 years

OBJECTIVE

To examine the self-perceived health of very low birth weight (VLBW; <1.5 kg) infants during young adulthood.

STUDY DESIGN

The population included 241 VLBW and 232 normal birth weight (NBW) controls who completed the Child Health and Illness Profile: Adolescent Edition (CHIP-AE) at 20 years of age. The CHIP-AE includes six domains: Satisfaction, Comfort, Resilience, Achievement, Risk Avoidance, and Disorders, and 13 profiles that characterize patterns of health. Results were compared between VLBW and NBW subjects adjusting for sex and sociodemographic status.

RESULTS

VLBW subjects did not differ from NBW controls in the domains of Satisfaction or Comfort but reported less Resilience (effect size [ES] -0.19, P < .05), specifically in physical activity and family involvement. They reported better Achievement, specifically in work performance (ES 0.28, P < .05), more Risk Avoidance (ES 0.43, P < .001), and significantly more long-term medical, surgical, and psychosocial disorders. Similar proportions of VLBW and NBW subjects reported Excellent (15% vs 11%), Average (27% vs 34%), and Poor (12% vs 13%) profiles of health.

CONCLUSIONS

VLBW subjects report similar health, well-being, and functioning compared with NBW controls and greater risk avoidance. However, we are concerned that their lesser resilience may prove detrimental to their future adult health.

Hospital readmissions and morbidity in a fifteen-year follow-up of very low birthweight children in Southeast Sweden

AIM

To study the effect of very low birthweight on hospital care and morbidity, and their relationship to gender, birthweight and neonatal complications.

METHODS

Eighty-five very low birthweight (VLBW; <or=1500 g) children and term controls born in 1987-1988 in south-east region of Sweden were checked in registers regarding readmissions and diagnoses, need for habilitation and child psychiatric care up to 15 years of age. Ophthalmological examinations were made at age 4 in 64 of VLBW and 61 of control children, and at age 15 in 59 of VLBW and 55 of control children.

RESULTS

VLBW boys had three times more readmissions compared with normal weight control boys (p=0.003). Neonatal risk factors for readmissions were gestational age under 30 weeks (OR 3.1), birthweight less than 1000 g (OR 4.6), mechanical ventilation (OR 9.5) and more than 60 days' stay in neonatal ward (OR 5.0). A minority of VLBW children had an impairment/handicap such as cerebral palsy (CP) in five (5.9%) children, attention deficit hyperactivity disorders (ADHD) in five children, and blindness due to retinopathy of prematurity in one child. One child in the control group had ADHD. At the 15-year examination median visual acuity in the best eye was better in the control group (1.6) than in the VLBW group (1.3) (p=0.009). 32% of VLBW children and 11% of controls had latent or manifest strabismus (p=0.007).

CONCLUSION

Risk factors for readmissions were gender, low gestational age, birthweight<1000 g or mechanical ventilation. A minority of VLBW children had a handicap that influenced their daily life activities at 15 years of age.

Impact of prenatal and/or postnatal growth problems in low birth weight preterm infants on school-age outcomes: an 8-year longitudinal evaluation

OBJECTIVE

The objective of this study was to assess the 8-year growth, cognitive, behavioral status, health status, and academic achievement in low birth weight preterm infants who had failure to thrive only, were small for gestational age only, had failure to thrive plus were small for gestational age, or had normal growth.

METHODS

A total of 985 infants received standardized evaluations to age 8; 180 infants met the criteria for failure to thrive between 4 and 36 months' gestational corrected age. The following outcome variables were collected at age 8: growth, cognitive, behavioral status, health status, and academic achievement. Multivariate analyses were performed among the 4 growth groups on all 8-year outcome variables.

RESULTS

Children who both were small for gestational age and had failure to thrive were the smallest in all growth variables at age 8, and they also demonstrated the lowest cognitive and academic achievement scores. The children with failure to thrive only were significantly smaller than the children with normal growth in all growth variables and had significantly lower IQ scores. Those who were small for gestational age only did not differ from those with normal growth in any cognitive or academic achievement measures. There were no differences among the 4 groups in behavioral status or general health status.

CONCLUSION

Low birth weight preterm infants who develop postnatal growth problems, particularly when associated with prenatal growth problems, demonstrate lower physical size, cognitive scores, and academic achievement at age 8. There does not seem to be an independent affect of small for gestational age status on 8-year cognitive status and academic achievement when postnatal growth is adequate.

The cognitive cost of being a twin: evidence from comparisons within families in the Aberdeen children of the 1950s cohort study

OBJECTIVES

To determine whether twins have lower IQ scores in childhood than singletons in the same family and, if so, whether differences in fetal growth explain this deficit.

DESIGN

Cohort study.

SETTING

Scotland.

PARTICIPANTS

9832 singletons and 236 twins born in Aberdeen between 1950 and 1956.

RESULTS

At age 7, the mean IQ score of twins was 5.3 points lower (95% confidence interval 1.5 to 9.1) and at age 9, 6.0 points lower (1.7 to 10.2) than that of singletons in the same family. Adjustment for sex, mother's age, and number of older siblings had little effect on these differences. Further adjustment for birth weight and gestational age attenuated the IQ difference between twins and singletons: the difference in mean IQ was 2.6 points (-1.5 to 6.7) at age 7 and 4.1 points (-0.5 to 8.8) at age 9.

CONCLUSIONS

Twins have substantially lower IQ in childhood than singletons in the same family. This effect cannot be explained by confounding due to socioeconomic, maternal, or other family characteristics, or by recruitment bias. The reduced prenatal growth and shorter gestations of twins may explain an important part of their lower IQ in childhood.

Post-discharge nutrition for the preterm infant

Newly designed, 'enriched,' formulas are now available for the formula feeding premature infant after hospital discharge. These new formulations add to the array of milks from which to choose when the discharge of the premature infant is approaching. However, the data to support optimal or reference nutrient intakes to use for the premature infant in the post-discharge are lacking. Breastfeeding should be encouraged as its beneficial effects may be related to the duration in which it is fed. Infants at risk for growth failure in the post-discharge period, such as infants unable to consume ad libitum intakes of milk, and who already have growth faltering or abnormal nutritional indices, may benefit for the addition of enriched formula. This review summarizes the recent data and comments on recommendations on post-discharge nutrition for premature infants.

Wheezing illness and re-hospitalization in the first two years of life after neonatal respiratory distress syndrome

OBJECTIVES

To determine the impact of respiratory distress syndrome (RDS) on wheezing illnesses and re-hospitalizations in children as old as 2 years of age.

STUDY DESIGN

We observed 2 geographically defined cohorts of children with RDS born after 26 weeks of gestation during 1990 to 1995 and 1996 to 1999 and gestationally paired control subjects. Recurrent wheezing illness and the re-hospitalizations caused by a respiratory condition were recorded.

RESULTS

In the first year of life, 47 of 224 infants with RDS and 18 of 224 control subjects born in 1990 to 1995 had recurrent wheezing illness (P <.005) compared with 21 of 109 infants with RDS and 14 of 109 control subjects in the latter cohort (P=.27). A higher number of infants with RDS were readmitted to the hospital (25% versus 13%, P=.002) in the former period, and they spent more days in hospital during both periods. The frequencies of wheezing remained constant in the second year of life, but hospital admissions decreased. Siblings at home, male sex, and bronchopulmonary dysplasia were additional risk factors of wheezing illnesses.

CONCLUSION

RDS increases the incidence of wheezing illnesses during the first 2 years of life. Changes in the management of RDS during the 1990s was associated with a decreased incidence of subsequent RDS-associated respiratory morbidity.

The endocrine consequences for very low birth weight premature infants

The aims of this study were: (1) to determine whether premature and small-for-gestational-age (SGA) children have alterations to the insulin-like growth factor (IGF)-IGF binding protein axis and (2) to evaluate growth in premature children. Three groups of children were evaluated: (i) premature children of </= 32 weeks gestation, which included appropriate-for-gestational-age (AGA) and small-for-gestational-age (SGA) subgroups; (ii) term children of >36 weeks gestation, which included AGA and SGA subgroups; and (iii) children born at term and AGA with normal childhood heights and weights. Fasting plasma IGF-I, insulin-like growth factor binding protein-3 (IGFBP-3), and IGF-II (all expressed as microgm/L) were drawn on available subjects. To examine the influence of SGA on the IGF-IGFBP axis, term SGA subjects were compared with term AGA subjects. To examine the influence of prematurity on the IGF-IGFBP axis, preterm SGA subjects were compared with term SGA subjects and preterm AGA subjects were compared with the normal-stature AGA controls. This ensured that groups of very similar stature and nutritional statuses were compared. Auxological data were available for 24 premature children, and biochemical data were available for 77 children, including the premature children. Across the height standard deviation score (SDS) range, premature children did not reach mid-parental height (MPH) SDS and were approximately 0.6 standard deviations (SDs) below the MPH SD (P < 0.0001). Plasma IGF-I and IGFBP-3 levels were higher in term SGA subjects compared with term AGA subjects (P < 0.001, respectively). Conversely, IGF-I and IGFBP-3 values were lower in the premature SGA subgroup compared with the premature AGA subgroup (P < 0.001 for both), and both were also lower in the premature AGA subgroup compared with the normal-statured AGA subgroup (P < 0.001 for both). IGF-II values were higher in the preterm group than in the term group (P < 0.001). In conclusion, very low birth weight (VLBW) children, regardless of whether they were AGA or SGA, have low plasma IGF-I and IGFBP-3 levels in mid-childhood, suggesting partial growth hormone (GH) resistance. Conversely, term SGA children have elevated plasma IGF-I and IGFBP-3 levels. When combined, premature birth plays a more dominant role than SGA on the IGF-IGF binding protein axis.

[Respiratory morbidity after hospital discharge in premature infants born at < or = 32 weeks gestation with bronchopulmonary dysplasia]

BACKGROUND

Bronchopulmonary dysplasia (BPD) is the most frequent cause of respiratory morbidity in the first 2 years of life among preterm infants who survive the first 28 days.

OBJECTIVES

To evaluate respiratory morbidity in the first 2 years of life in a group of preterm infants born at (32 weeks' gestation with BPD (oxygen requirement at 36 weeks' postconceptional age) by comparing it with that in preterm infants born at (32 weeks without BPD and with a control group of full term infants without neonatal morbidity. To determine whether respiratory morbidity in children with BPD decreases after the age of 2 years.

PATIENTS AND METHOD

Group I: preterm children with BPD (n = 29). Group II: preterm children without BPD (n = 29). Group III: children with appropriate gestational age and weight (n = 32). A cross-sectional, descriptive study of the three groups was performed over a 2-year period. In 17 children in group 1, the study was prolonged to the age of 4 years. We analyzed wheezing on at least two occasions, use of inhaled bronchodilators, use of inhaled glucocorticosteroids for more than 6 months, and hospitalization for respiratory illness. The chi-square test and Fischer's exact test were performed.

RESULTS

At least one episode of wheezing occurred in 25 children (86.2%) in group I compared with 12 children (41.4%) in group II and 6 (18.8%) in group III. Nineteen children (65.5%) in group I and none in the remaining two groups received treatment with inhaled glucocorticosteroids for more than 6 months (p < 0.001). Inhaled bronchodilators were used by 25 children (86.2%) in group I compared with 12 (41.4%) in group II and 6 (18.8%) in the control group (p < 0.001). Twelve children (41.3%) in group I were hospitalized for respiratory illness compared with 8 (27.6%) in group II. There were no admissions among the control group. None of the children with BPD who received prophylaxis with palivizumab contracted respiratory syncytial virus infection. Seventeen children with BPD were evaluated until the age of 4 years. Episodes of wheezing decreased from 88.2% in the first year to 41 % between the third and fourth years (p < 0.001). Treatment with inhaled glucocorticosteroids for more than 6 months was given to 88.2% in the first year, 41.2 % between the first and second year and to 0 % after the second year (p < 0.001). Hospital admissions for respiratory illness decreased from 52.9% in the first year to 17.6% in the second year. None of the children were hospitalized after the age of 2 years (p < 0.001).

CONCLUSIONS

During the first 2 years of life, children with BPD showed a greater number of admissions and episodes of wheezing and a greater need for medical treatment. Respiratory morbidity improved with age, 40% showed recurrent wheezing episodes at the age of 4 years.

Longitudinal outcomes of very low birth weight: neuropsychological findings

To investigate the effects of very low birth weight (VLBW, &1500 g) on the development of neuropsychological skills, we assessed 67 children with birth weight <750 g, 64 with birth weight 750-1499 g, and 67 term-born controls. Growth modeling of raw scores from mean ages 7-14 years revealed persistent VLBW sequelae. Even when adjusting for IQ, the <750 g group scored more poorly than the term-born group on measures of language processing, verbal list learning, and perceptual-motor and organizational abilities. This group also made slower age-related progress than the control group on tests of perceptual-motor and executive functions. Environmental factors moderated group differences in change on other cognitive measures. These results revealed further evidence for slower skill development in both VLBW groups relative to controls, as well as"catch-up" growth in the 750-1499 g group on some measures. The findings suggest age-related changes in the cognitive sequelae of VLBW that depend on the skill assessed, the degree of VLBW, and environmental factors.

Variation in childhood asthma among former preterm infants

OBJECTIVES

The role of in utero and perinatal exposures in modifying asthma risk among children born prematurely was assessed. Study design Former preterm children (n=251) were identified from a birth cohort. Examinations, including lung function testing, were performed at ages 8 to 11 years. Perinatal exposures were ascertained from neonatal medical records.

RESULTS

Univariate predictors of asthma included male gender, African American ethnicity, maternal asthma, and birth weight. Asthmatics were less likely to have been small for gestational age (SGA) than nonasthmatics (12.4% vs 22.7%, P=.04) and had more neonatal pulmonary disease. After adjusting for maternal asthma and demographic factors, asthma was associated with chronic lung disease of infancy, neonatal mechanical ventilation and corticosteroid use, and a higher childhood body mass index. Children who were septic postbirth and girls who were SGA were less likely to have asthma (OR for sepsis, 0.2; 95% CI, 0.1-0.6; OR for girls who were SGA compared with girls who were not SGA, 0.05; CI, 0.01-0.34).

CONCLUSIONS

Among premature children, female SGA status and neonatal sepsis appear protective relative to the development of childhood asthma. Differential susceptibility to asthma among preterm children may relate to exposures that operate in the in utero and early postnatal environment to accelerate lung development, alter innate immunity, or both.

Pulmonary function and exercise capacity for ELBW survivors in preadolescence: effect of neonatal chronic lung disease

OBJECTIVE

To assess pulmonary function and exercise capacity of apparently asymptomatic children who were born extremely preterm.

STUDY DESIGN

Pulmonary function and treadmill testing were performed on 50 children 9 to 15 years old who had birth weight <801 g (extremely low birth weight [ELBW]) and without apparent neurodevelopmental or pulmonary disabilities, compared with 25 children born at term with normal birth weight (NBW). Medical history and physical activity levels were assessed by parent questionnaire. Group differences were determined by two-sample t test. Secondary analysis was performed to assess significant influence of neonatal chronic lung disease (CLD) on outcome measures.

RESULTS

Twenty percent of ELBW subjects but no subjects with NBW had clinically abnormal pulmonary function (>2 SD from norms, P=.026). All significant pulmonary function differences except peak expiratory flow rate percentages were accounted for by ELBW subjects who had CLD. Oxygen consumption measurements were significantly lower for subjects with ELBW (30.3+/-6.9 and 38.5+/-5.2 mL/kg/min, P=.000), independent of CLD status.

CONCLUSION

Pulmonary function abnormalities consistent with obstructive lung disease were more frequently detected in ELBW children who had neonatal CLD. Low oxygen consumption measurements suggest a lower level of fitness for ELBW children compared with children with NBW.

Use of healthcare resources, family function, and socioeconomic support during the first four years after preterm birth

OBJECTIVES

To assess the use of healthcare resources for preterm infants and to evaluate family function and socioeconomic support in a defined population from birth to 4 years of age.

METHODS

In a prospective case-control study, 39 singleton preterm infants without prenatal abnormalities born during an 18 month period were studied together with their families. The population consisted of 19 very preterm infants (less than 32 weeks) and 20 randomised moderate preterm infants (32-35 weeks), and the control group comprised 39 full term infants. Contacts with medical services, child health services, and the social welfare system were registered, and family function and life events were studied.

RESULTS

The preterm children were more often readmitted to hospital (odds ratio (OR) 6.6, 95% confidence interval (CI) 2.0 to 22.1) and had more outpatient attendances (OR 5.6, 95% CI 2.1 to 15.0) during their first year of life. Mothers in the preterm group more often used temporary parental allowance than the control mothers (p < 0.001). The number of contacts with the child health services and the social welfare system did not differ significantly from the controls. Neither was there any significant difference with regard to family function or life events at 4 years of age.

CONCLUSIONS

A large proportion of the premature children used specialist care during the first years of life. However, the families of the preterm infants were socially well adapted up to four years after birth compared with the control families.

Growth of very low birth weight infants to age 20 years

OBJECTIVE

Intrauterine and neonatal growth failure of very low birth weight (VLBW; <1500 g) infants may influence adult growth attainment and have long-term implications for adult health. As part of a longitudinal study of VLBW infants, we sought to examine gender-specific changes in growth from birth to 20 years old and to identify the correlates of growth attainment at 20 years old.

DESIGN, SETTING, PARTICIPANTS

A cohort of 103 male and 92 female VLBW infants who had a mean birth weight of 1189 g and mean gestational age of 29.8 weeks, were born from 1977 through 1979 and treated at Rainbow Babies and Children's Hospital in Cleveland, Ohio, and were free of neurosensory impairment were followed prospectively from birth and compared with a population-based sample of 101 male and 107 female normal birth weight (NBW) controls selected at 8 years old. Maternal sociodemographic status and infant birth and neonatal data did not differ significantly between male and female VLBW subjects. However, male VLBW subjects had significantly higher rates of rehospitalization during infancy than female VLBW (39% vs 21%). At 20 years, their rates of chronic illness were similar (18% vs 24%).

MAIN OUTCOME MEASURES

Weight and height z scores were computed at birth, 40 weeks, 8 and 20 months, and 8 and 20 years among the VLBW subjects, and at 8 and 20 years among the NBW controls. Body mass index (BMI) z scores were computed at 8 and 20 years. Among the VLBW subjects, gender-specific longitudinal growth measures were examined at birth, at the expected term date (40 weeks corrected age), and at 8 and 20 months, and 8 and 20 years of age. In addition, we compared the weight, height, and BMI of the VLBW and NBW controls at 8 and 20 years. Predictors of 20-year growth were examined via multivariate analyses.

RESULTS

Among the VLBW males, mean weight for age z scores at birth, 40 weeks, and 8 years were -0.7, -1.8, and -0.5; and height for age z scores were -1.2, -2.6, and -0.5, respectively. For VLBW females, mean weight for age z scores were -1.1, -2.0, and -0.2 and height for age z scores were -1.2, -2.4, and -0.2, respectively. At 8 years of age, VLBW males had a significantly lower mean weight, height, and BMI than NBW controls, whereas VLBW females differed significantly from their NBW controls in mean weight and BMI but not in height. Catch-up growth in weight, height, and BMI occurred between 8 and 20 years among VLBW females but not among VLBW males who remained significantly smaller than their controls at 20 years old. At 20 years mean weight of VLBW males was 69 kg versus 80 kg for controls (z score -0.4 vs +0.5); mean height was 174 cm versus 177 cm (z score -0.4 vs +0.03) and mean BMI was 23 versus 26, respectively. For VLBW females, mean weight was 65 kg versus 68 kg for controls (z score +0.3 vs +0.5), mean height was 162 versus 163 cm (z score -0.3 vs -0.1) and mean BMI was 25 versus 25, respectively. Rates of obesity (BMI >30) for VLBW males were 7% compared with 15% for controls and for VLBW females 15% compared with 18% for controls. Age of menarche was 12.4 years for VLBW females and 12.3 years for controls. Nineteen (18%) male and 20 (22%) female VLBW subjects were born small for gestational age (SGA; weight less than -2 standard deviation for gestational age). At 20 years, significantly more SGA than appropriate for gestational age VLBW males remained subnormal (less than -2 standard deviation) in weight (32% vs 6%) and height (21% vs 4%), whereas rates of subnormal growth did not differ significantly between SGA and appropriate for gestational age females (weight 5% vs 1%, height 0% vs 7%). Predictor variables included in the multivariate analyses of 20-year growth attainment were maternal education and height, race, birth weight z score (a measure of intrauterine growth failure), neonatal hospital stay (a measure of neonatal illness), and chronic illness at 20 years. Twenty-year weight was predicted by black race and chronic illness among females. Twenty-year height was predicted by maternal height and birth weight z score among both males and females and by duration of neonatal hospital stay among males only. In a separate model, when we examined the effect of being SGA at birth instead of the effect of birth weight z score, SGA birth was predictive of 20-year height among males but not among females.

CONCLUSIONS

VLBW females catch up in growth by 20 years of age whereas VLBW males remain significantly shorter and lighter than controls. Since catch-up growth may be associated with metabolic and cardiovascular risk later in life, these findings may have implications for the future adult health of VLBW survivors.

Human milk reduces outpatient upper respiratory symptoms in premature infants during their first year of life

OBJECTIVE

To determine if ingestion of human milk after discharge reduces symptoms of infections in premature infants.

STUDY DESIGN

Follow-up of 39 infants with birth weights <2000 g, 24 of whom received any amount of human milk and 15 of whom received only formula after discharge, was carried out. Mothers were given a calendar on which they recorded any signs of infections and feeding and day-care information. Data were collected at 1 month after discharge and at 3, 7, and 12 months corrected age.

RESULTS

Results show no differences between groups in birth weight, gestation, gender, maternal age, parental tobacco use, number of siblings, and day-care attendance. Socioeconomic status score was higher in the human milk group. Infants who received human milk had fewer days of upper respiratory symptoms at 1 month after discharge (p<0.025) and at 7 months corrected age (p<0.025).

CONCLUSION

Ingestion of human milk post discharge is associated with a reduction of upper respiratory symptoms in premature infants during their first year of life.

Outcomes in young adulthood for very-low-birth-weight infants

BACKGROUND

Very-low-birth-weight infants (those weighing less than 1500 g) born during the initial years of neonatal intensive care have now reached young adulthood.

METHODS

We compared a cohort of 242 survivors among very-low-birth-weight infants born between 1977 and 1979 (mean birth weight, 1179 g; mean gestational age at birth, 29.7 weeks) with 233 controls from the same population in Cleveland who had normal birth weights. We assessed the level of education, cognitive and academic achievement, and rates of chronic illness and risk-taking behavior at 20 years of age. Outcomes were adjusted for sex and sociodemographic status.

RESULTS

Fewer very-low-birth-weight young adults than normal-birth-weight young adults had graduated from high school (74 percent vs. 83 percent, P=0.04). Very-low-birth-weight men, but not women, were significantly less likely than normal-birth-weight controls to be enrolled in postsecondary study (30 percent vs. 53 percent, P=0.002). Very-low-birth-weight participants had a lower mean IQ (87 vs. 92) and lower academic achievement scores (P<0.001 for both comparisons). They had higher rates of neurosensory impairments (10 percent vs. <1 percent, P<0.001) and subnormal height (10 percent vs. 5 percent, P=0.04). The very-low-birth-weight group reported less alcohol and drug use and had lower rates of pregnancy than normal-birth-weight controls; these differences persisted when comparisons were restricted to the participants without neurosensory impairment.

CONCLUSIONS

Educational disadvantage associated with very low birth weight persists into early adulthood.

Physical growth and current health status of infants who were of extremely low birth weight and controls at adolescence

OBJECTIVES

To compare the physical growth, current health status, and utilization of health care resources by extremely low birth weight (ELBW) and control (C) adolescents and to look at changes over time.

METHODS

A longitudinal regional cohort study was conducted. Growth measures were converted to z scores on the National Center for Health Statistics growth curves. Information regarding current health status/health care utilization was obtained by parental interviews.

RESULTS

A total of 154 (91%) of 169 ELBW survivors between 12 and 16 years and 125 (86%) of 145 controls participated. Neurosensory impairments were present in 28% of ELBW survivors and 2% of control participants. Mean z scores for both height and weight were below 0 for ELBW survivors (weight: -0.35; height: -0.55) compared with control participants (weight: 0.40; height: 0.28). However, among ELBW survivors, significant catch-up growth occurred in both parameters between age 8 and adolescence but remained stable among control participants. ELBW survivors had a higher prevalence of visual problems (57% vs 21%), seizures (7% vs 1%), developmental delay (26% vs 1%), learning disabilities (34% vs 10%), and hyperactivity (9% vs 2%) and used more specialists and community resources than did control participants.

CONCLUSIONS

Although physical growth continues to be compromised and substantial morbidity remains among ELBW survivors at adolescence, there seems to be some catch-up growth, a reduction in the prevalence of acute health problems, and a decrease in the utilization of medical resources.

Growth of preterm infants fed nutrient-enriched or term formula after hospital discharge

OBJECTIVE

At hospital discharge, preterm infants may have low body stores of nutrients, deficient bone mineralization, and an accumulated energy deficit. This double-blind, randomized study evaluated the growth of premature infants with birth weights <1800 g who were fed a 22 kcal/fl oz nutrient-enriched postdischarge formula (PDF) or a 20 kcal/fl oz term-infant formula (TF) from hospital discharge to 12 months' corrected age (CA).

METHODS

Infants were randomized to PDF or TF a few days before hospital discharge with stratification by gender and birth weight (<1250 g or >/=1250 g). The formulas were fed to 12 months' CA. Growth was evaluated using analysis of variance controlling for site, feeding, gender, and birth weight group. Interaction effects were also assessed. Secondary analyses included a repeated measures analysis and growth modeling.

RESULTS

One hundred twenty-five infants were randomized; 74 completed to 6 months' CA and 53 to 12 months' CA. PDF-fed infants weighed more than TF-fed infants at 1 and 2 months' CA, gained more weight from study day 1 to 1 and 2 months' CA, and were longer at 3 months' CA. There were significant interactions between feeding and birth weight group-among infants with birth weights <1250 g, those fed PDF weighed more at 6 months' CA, were longer at 6 months' CA, had larger head circumferences at term 1, 3, 6, and 12 months' CA, and gained more in head circumference from study day 1 to term and to 1 month CA. The repeated measures and growth modeling analyses confirmed the analysis of variance results. The PDF formula seemed to be of particular benefit for the growth of male infants. Infants fed the PDF consumed less formula and had higher protein intakes at several time points. Energy intakes, however, were not different.

CONCLUSIONS

Growth was improved in preterm infants fed a nutrient-enriched postdischarge formula after hospital discharge to 12 months' CA. Beneficial effects were most evident among infants with birth weights <1250 g, particularly for head circumference measurements.

Very low birthweight and asthma by age seven years in a national cohort

Several studies have suggested that very low birthweight (VLBW < 1500 g) is associated with increased rates of respiratory problems in childhood and that the presence of chronic lung disease further increases the risk. We aimed to assess rates of asthma at 7-8 years of age in a national cohort of VLBW infants born in 1986 and for whom perinatal data were available. Two hundred ninety-nine former VLBW children (96% of surviving children living in New Zealand) were assessed at a home visit. Parents were asked a comprehensive questionnaire, including three questions aimed at assessing morbidity from asthma: 1) was the child diagnosed as having asthma before age 7 years; 2) was the child still experiencing asthma at the age of 7 years; and 3) was the child prescribed daily medication for asthma at the age of 7 years. Overall, 50% of the cohort had been diagnosed with asthma before age 7, compared with 27% of a sample of New Zealand children assessed contemporaneously in an international study; 32% had asthma at age 7, and 11% were taking daily medication. All three categories of asthma were associated with a family history of asthma, but there was no association with any perinatal factors. A diagnosis of asthma before age 7 was more likely when the mother smoked in pregnancy (P < 0.005) and currently smoked (P < 0.01), and trended so when parents lacked high school qualifications and in Maori or Pacific Island families (P < 0.10). In contrast, daily medication was more frequent when parents had educational qualifications and in non-Maori or Pacific Island families (P < 0.05). On multiple logistic regression, a family history of asthma was a significant predictor for any and current asthma (P < 0.001) and daily medication (P < 0.05); maternal smoking in pregnancy was a significant predictor for any asthma (P < 0.05); and non-Maori or Pacific Island ethnicity was a significant predictor for asthma treatment (P < 0.05). We conclude that rates of childhood asthma are high in this VLBW cohort, but the high prevalence appears to be unrelated to perinatal factors, including respiratory morbidity. There are suggestions that social factors contribute to both asthma risk and treatment.

Estimation of neonatal outcome and perinatal therapy use

OBJECTIVES

To learn whether US obstetricians and pediatricians accurately estimate rates of survival and freedom from handicap in preterm infants and to learn whether their knowledge and attitudes influence their choice of interventions that may enhance survival.

METHODS

A cross-sectional survey of obstetricians and pediatricians practicing in the United States was performed using a pretested questionnaire designed to identify their knowledge regarding survival and handicap-free rates of infants born at 23 to 36 weeks of gestation. At each week of gestation, they were asked whether they would provide specific therapeutic interventions to either the expectant mother or infant. Survival and handicap-free rates were compared with published national rates. Obstetricians and pediatricians were divided into an optimists group and a pessimists group, based on their estimates of survival. The rates at which each group used therapeutic interventions were compared.

RESULTS

Both obstetricians and pediatricians underestimated survival rates from 24 through 35 weeks of gestation and freedom from serious handicap from 23 through 36 weeks of gestation. On the average, optimists accurately predicted neonatal survival. Obstetricians who underestimated neonatal survival would less often administer antenatal corticosteroids, perform a cesarean section for fetal distress, and transfer a mother to a tertiary center. Pediatricians who underestimated neonatal survival would less often use mechanical ventilation, cardiopulmonary resuscitation, inotropes, intravenous fluids, thermal support, and oxygen supplementation.

CONCLUSION

Physicians underestimate survival and freedom from handicap in preterm infants. Underestimation of outcome is associated with restriction in the use of appropriate interventions.

School difficulties at adolescence in a regional cohort of children who were extremely low birth weight

OBJECTIVES

To compare measures of psychometric assessment and school difficulties in a cohort of extremely low birth weight (ELBW) teenagers and term controls, and to determine whether there is stability in psychometric measures between age 8 and the teen years.

STUDY DESIGN

Longitudinal follow-up; geographically defined region.

PARTICIPANTS

150 of 169 (89%) ELBW survivors born between 1977 and 1982 and 124 of 145 (86%) sociodemographically matched term controls between 12 and 16 years of age. Psychometric measures: Wechsler Intelligence Scale for Children-Revised, Wide Range Achievement Test-Revised, and a validated parent questionnaire.

RESULTS

Neurosensory impairments were present in 28% of ELBW and 1% of controls. The mean Wechsler Intelligence Scale for Children-Revised scores were ELBW: 89 +/- 19 and controls: 102 +/- 13. ELBW children did less well on Wide Range Achievement Test-Revised Reading, Spelling, and Arithmetic measures with mean scores in the range from 75 to 85. ELBW children <750 g were more disadvantaged, compared with those >/=750 g. A significantly higher proportion of ELBW children were receiving special educational assistance and/or had repeated a grade (ELBW: 58%; controls: 13%; odds ratio: 9.0). Paired analysis of within-cohort data at age 8 and teen years showed that for both cohorts Arithmetic scores declined, but there were small improvements in other measures, predominantly in the term children.

CONCLUSIONS

Differences of 13 to 18 points in psychometric measures in ELBW teens compared with controls are both statistically significant and clinically relevant. Decreasing birth weight was associated with increased risk on all measures. The high utilization of special educational resources has economic implications, and the incremental cost attributable to being extremely premature needs to be determined.

The physical health of rural mothers and their low birth weight children

The purpose of this research was to examine the physical health of rural mothers and their low birth weight children (< 2,500 gm). The health of rural mothers is of concern because rural families have poorer health than urban ones, and as the primary caregiver for the low birth weight child, mother's health affects the child's care and potentially the child's health. In this cross-sectional, exploratory study, in-home interviews were conducted with 48 mothers between 2 weeks and 18 months after their children were discharged from their birth hospitalization. Mothers' physical health and their perceptions of their children's health were assessed. The mothers were more concerned about their children's health than their own (p = .0005). The concerns included uncertainty about the children's future health, growth, and development. Suggestions for community health care providers are addressed.

Positive Pre‐conception Partnerships: The Essential Ingredient for Good Mental Health

Ensuring that a child has a good start in life requires a partnership that extends beyond that of the parents and that precedes a child's conception. Sharing this vision among agencies that have contact with marginalised young people led to the use of an infant simulator to attract ‘at risk’ young people into a program that helps ensure that the choice to conceive is not only informed but also has the potential to promote mental health. Participants demonstrated that they increased their knowledge of the health and other implications of having a baby and some took active measures to improve their health.

Rehospitalization in the first two weeks after discharge from the neonatal intensive care unit

BACKGROUND

High-risk newborns are known to have higher than average utilization of services after discharge from the neonatal intensive care unit (NICU). Most studies on this subject report aggregate data over periods ranging from 1 to 3 years postdischarge. Little is known about events that are temporally close to NICU discharge.

OBJECTIVES

To characterize rehospitalizations within the first 2 weeks after discharge from six community NICUs.

METHODS

We scanned electronic databases and reviewed the charts of rehospitalized infants from six NICUs in the Kaiser Permanente Medical Care Program. We subdivided infants into five groups based on gestational age (GA) and birth hospitalization length of stay (LOS): 1) >/=37 weeks' GA with <4 days LOS (n = 2593); 2) >/=37 weeks' GA with >/=4 days' LOS (n = 1133); 3) from 33 to 36 weeks' GA with <4 days' LOS (n = 545); 4) from 33 to 36 weeks' GA with >/=4 days' LOS (n = 1196); and 5) <33 weeks' GA (n = 587). We performed bivariate and multivariate analyses to identify predictors that might be useful for practitioners.

RESULTS

There were 6054 newborns discharged alive from the six study NICUs between August 1, 1992 and December 31, 1995, and 99.5% of these infants remained in the health plan during the 2 weeks after NICU discharge. The overall rehospitalization rate was 2.72%, which is 20% higher than the rate among healthy term newborns in the Kaiser Permanente Medical Care Program (2.26%). The two most common reasons for rehospitalization were jaundice (62/165, 37.6%) and feeding difficulties (25/165, 15.2%). Infants with 33 to 36 weeks' GA and <4 days' LOS were rehospitalized at a significantly higher rate than were all other infants (5.69%); 71% of infants in this group were rehospitalized for jaundice. The following variables predicted rehospitalization in multivariate models: <33 weeks' GA (adjusted OR [AOR]: 1.88; 95% CI: 1.10-3.21), from 33 to 36 weeks' GA with <96 hours' LOS (AOR: 2.94; 95% CI: 1.87-4.62), and birth at facility B, which had the highest rehospitalization rate of the six facilities (AOR: 1.92; 95% CI: 1.39-2.65).

CONCLUSIONS

The rate of rehospitalization among NICU graduates is higher than among healthy term infants. Most of the rehospitalizations among infants with from 33 to 36 weeks' GA and <4 days' LOS are for illnesses that are not life-threatening. Collaborative studies and new process and outcomes measures are needed to assess the effectiveness of follow-up strategies in high-risk newborns.

Medical and ecological factors in estimating motor outcomes of preschool children

The twofold purpose of this study was to compare motor function in preschool children born with varying degrees of medical risk and to determine the independent contribution to motor function of three domains of ecological influence. One hundred and eighty-four 4-year-old children and their mothers participated. Three predictor sets, proximal, distal, and child, and four motor outcomes were measured by multiple methods. Children born prematurely scored lower on all dimensions of motor function. Prematurity complications had a different effect on motor function. Hierarchical regression models explained 16-40% of motor score variance. Results are discussed in relation to heterogeneity of prematurity and ecological influences on motor outcomes.

Hearing screening in at-risk neonate cohort

OBJECTIVE

This prospective study reports on the prevalence of hearing impairment in an at-risk neonatal intensive care unit (NICU) population.

DESIGN

From 1990 to 1997, 942 neonates were screened with transient evoked otoacoustic emissions (TEOAE) and brainstem evoked response audiometry (BERA).

RESULTS

835 Infants passed the primary screen for both ears, 57 for one ear, adding up to 94.7%. Seventeen infants (1.9%) were lost to follow-up. In thirteen infants (1.4%), bilateral hearing impairment above 30 dB was confirmed. While all children with hearing impairment belonged to the group of 820 children receiving aminoglycosides, only one presented no other risk factors. In 11 of the hearing impaired children other anamnestic factors, i.e. dysmorphism, prenatal rubella or cytomegaly, family history of hearing loss or severe peri- and postnatal complications seem to be more probable causes of the identified hearing loss.

CONCLUSIONS

From our data, aminoglycosides seem not to be an important risk factor for communication related hearing impairment, when serum levels are continuously monitored, as occurred in our cohort. After adjustment for other risk factors, birth weight between 1000 and 1500 g and a gestational age between 29 and 31 weeks were no predictive markers for hearing impairment. It might be speculated that the improved medical treatment in a Neonatal Intensive Care Unit (NICU) reduces the probability of hearing impairment for those two groups. Conductive hearing loss as a possible additional cause for hearing impairment was not studied in detail, but the high percentage of malformations detected (four out of 13 hearing impaired infants) demands further monitoring, close follow-up, counselling and adequate treatment.

Health, growth, and use of community services in NICU graduates at early school age

PURPOSE

To examine outcomes related to health, growth, and use of community health and education services in children ages 6 to 8 years who received newborn intensive care because of prematurity or perinatal complications.

METHOD

Parents of 81 children who had received neonatal intensive care at a Midwest US tertiary care center completed a mailed questionnaire. Three birth weight groups (very low birth weight [VLBW] < 1500 g, n = 35; low birth weight [LBW] 1501-2500 g, n = 24, and normal birth weight [NBW] > 2500 g, n = 22) were compared regarding growth, health, and use of community-based services using descriptive statistics and one-way analysis of variance.

FINDINGS

VLBW and NBW groups had more ongoing health concerns. Growth patterns were similar in all groups. VLBW and NBW groups demonstrated greater use of community-based services, and service use increased at school age.

CONCLUSIONS

Comprehensive systems are needed for follow-up of high-risk infants to detect and refer problems early. Neonatal histories must be tracked throughout childhood. Seriously ill term NBW infants are at risk for later morbidity and require follow-up similar to that provided for VLBW children.

Estimation of outcome and restriction of interventions in neonates

OBJECTIVE

To learn whether pediatricians accurately estimate rates of survival and freedom from handicap in preterm infants and to learn whether their knowledge and attitude influence their choice of interventions that may enhance survival of extremely preterm infants.

METHODS

Pediatricians practicing in Alabama were surveyed using a pretested questionnaire designed to identify pediatricians' knowledge regarding survival and handicap-free rates of infants born at gestational ages between 21 and 36 weeks. For infants born at each week of gestation, they were asked if they would provide specific therapeutic interventions. Survival and handicap-free rates were compared with published national rates. Pediatricians were divided into an optimist group and a pessimist group based on how their estimates of survival compared with national published data. The rates at which each group used therapeutic interventions were compared.

RESULTS

The 159 (57%) responding pediatricians underestimated survival rates from 23 through 34 weeks' gestation and freedom from serious handicap from 23 through 36 weeks. Responses of the optimists approximated actual data whereas the pessimists underestimated neonatal outcome. Those pediatricians who underestimated neonatal outcome would intervene less often with invasive therapies, including mechanical ventilation, cardiopulmonary resuscitation, inotropes, and intravenous fluids, compared with those who accurately predicted outcome from 23 through 27 weeks' gestation.

CONCLUSION

Pediatricians often underestimate neonatal outcome of preterm infants. Appropriate neonatal practice may be affected by this underestimation of the survival potential of preterm infants.

Evaluation of criteria for chronic lung disease in surviving very low birth weight infants. Newborn Lung Project

Criteria in common use for the diagnosis of chronic lung disease of prematurity or bronchopulmonary dysplasia in the neonatal period have not been sufficiently compared and validated against indicators of later respiratory complications. In this study of all 680 infants < or = 1500 gm birth weight admitted to six perinatal centers August 1, 1988, to July 31, 1990, 524 were alive and had no major congenital anomalies at 5 years old. Of 419 who had given permission to release their names and addresses, 272 were located and participated in a follow-up study. The following diagnostic criteria for bronchopulmonary dysplasia and chronic lung disease of prematurity were used during the initial hospitalization: (1) use of supplemental oxygen on day 30 of life, (2) a comprehensive bronchopulmonary dysplasia severity score applied at 25 to 35 days of life developed by a clinician panel to adjust for practice variation in ventilatory support and blood gases, (3) use of supplemental oxygen on day 30 of life with radiographic evidence consistent with bronchopulmonary dysplasia between days 25 and 35 of life, (4) radiographic evidence consistent with bronchopulmonary dysplasia alone, and (5) use of supplemental oxygen at 36 weeks' postconceptional age. These criteria were assessed against use of bronchodilators or steroids during the first 2 years of life, diagnosis of asthma, and hospitalizations for respiratory causes up to age 5. Although all criteria were significantly associated with all the outcomes, radiographic evidence was most predictive. These results indicate that, during a period when 21% of neonates were exposed to antenatal steroids, 24% received surfactant and 9% received postnatal corticosteroids, radiographic evidence was more predictive of long-term respiratory outcome than other commonly used criteria.

Breastfeeding infants who were extremely low birth weight

OBJECTIVE

To compare the clinical effect of breastfeedings and bottle feedings in extremely low birth weight (ELBW) infants (birth weight </=800 g).

METHODS

A total of 12 ELBW infants (mean birth weight, 672 +/- 95 g; mean gestation, 26 +/- 2 weeks) served as their own controls in this prospective study comparing physiologic parameters during bottle and breastfeeding. The infants were put to breast the same week they began on bottle feedings of human milk or premature infant formula (mean gestation, 35 weeks). One breastfeeding and one bottle feeding were observed each day for 10 days. Pre- and postfeeding weights were measured, and oxygen saturation, respiratory rate, heart rate, and axillary temperature were monitored continuously and recorded every minute during feedings.

RESULTS

The infants demonstrated a higher oxygen saturation and a higher temperature during breastfeeding than during bottle feeding, and were less likely to desaturate to <90% oxygen during breastfeeding. Mean weight gain was greater during bottle feeding than during breastfeeding (31 vs 9 g).

CONCLUSIONS

Breastfeeding the ELBW infant is desirable from a standpoint of improved physiologic responses, but such practice requires breastfeeding support and possible supplementation to optimize weight gain.

School age outcome in low birth weight preterm infants

Very low birth weight (VLBW) children at school age show variability in their outcome, compared with normal birth weight children, although many early physical and health differences are equalized by middle childhood. Studies of nonhandicapped VLBW children have found a higher rate of school retention and school problems in this population. Differences in intelligence have been reported, although these are often confounded by socioeconomic factors such as educational level of the parent. Few studies today of children born in the late 1970s and early 1980s have related school age outcome to central nervous system (CNS) status, yet for learning disabilities or other neuropsychological deficits, this may be highly relevant. Better understanding of medical risk factors, however, will not affect the decisive influence of social factors on their expression in the school age child.

Obstetric determinants of neonatal survival: influence of willingness to perform cesarean delivery on survival of extremely low-birth-weight infants. National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units

OBJECTIVE

Our purpose was to evaluate the relationship between the approach to obstetric management and survival of extremely low-birth-weight infants.

STUDY DESIGN

In this prospective observational study we evaluated 713 singleton births of infants weighing < or = 1000 gm during 1 year at the 11 tertiary perinatal care centers of the National Institutes of Child Health and Human Development network of maternal-fetal medicine units. Major anomalies, extramural delivery, antepartum stillbirth, induced abortion, and gestational age < 21 weeks were excluded. The obstetrician's opinion of viability and willingness to perform cesarean delivery in the event of fetal distress were ascertained from the medical record or interview when documentation was unclear. Grade 3 and 4 intraventricular hemorrhage, grade 3 and 4 retinopathy of prematurity, necrotizing enterocolitis requiring surgery, oxygen dependence at discharge or 120 days, and seizures were considered serious morbidity. Survival without serious morbidity was considered intact survival. Logistic regression was used to evaluate the influence of the approach to obstetric management, adjusted for birth weight, growth, gender, presentation, and ethnicity.

RESULTS

Willingness to perform cesarean delivery was associated with increased likelihood of both survival (adjusted odds ratio 3.7, 95% confidence interval 2.3 to 6.0) and intact survival (adjusted odds ratio 1.8, 95% confidence interval 1.0 to 3.3). Willingness to intervene for fetal indications appeared to virtually eliminate intrapartum stillbirth and to reduce neonatal mortality. Below 800 gm or 26 weeks, however, willingness to perform cesarean delivery was linked to an increased chance of survival with serious morbidity. Although obstetricians were willing to intervene for fetal indications in most cases by 24 weeks, willingness to perform cesarean delivery was associated with twice the risk for serious morbidity at that gestational age.

CONCLUSIONS

The approach to obstetric management significantly influences the outcome of extremely low-birth-weight infants. Above 800 gm or 26 weeks the obstetrician should usually be willing to perform cesarean delivery for fetal indications. Between 22 and 25 weeks willingness to intervene results in greater likelihood of both intact survival and survival with serious morbidity. In these cases patients and physicians should be aware of the impact of the approach to obstetric management and consider the likelihood of serious morbidity and mortality when formulating plans for delivery.

Comparison of morbidities in very low birthweight and normal birthweight infants during the first year of life in a developing country

OBJECTIVE

To compare the morbidities in the very low birthweight (VLBW; < 1500 g) and normal birthweight (NBW; > or = 2500 g) Malaysian infants during the first year of life.

METHODOLOGY

Prospective observational cohort study of consecutive surviving VLBW infants and randomly sampled NBW infants born in the Kuala Lumpur Maternity Hospital between 1 December 1989 and 31 December 1992. Infants were followed up regularly during the first year of life, after correction for prematurity.

RESULTS

Compared with NBW infants (n = 106), VLBW infants (n = 127) had significantly higher risk of failure to thrive (odds ratio [OR] = 8.0, 95% confidence intervals [CI]: 1.1 to 354.3), wheezing (OR = 3.7, 95% CI: 1.6 to 9.3), rehospitalization (OR = 2.3, 95% CI: 1.1 to 5.0), cerebral palsy (OR = 8.6, 95% CI: 2.0 to 77.6), neurosensory hearing loss (OR = 12.0, 95% CI: 1.7 to 513.6) and visual loss (7.9 vs 0%, P = 0.002). The mean mental developmental index (MDI) and mean psychomotor developmental index (PDI) at 1 year of age were significantly lower among VLBW infants (MDI 99 [SD = 28], PDI 89 [SD = 25]) than NBW infants (MDI 106 [SD = 18], PDI 101 [SD = 18]) (95% CI for difference between means being MDI: -14.1 to -1.7; and PDI: -17.6 to -6.0). Logistic regression analysis showed that among VLBW infants: (i) male sex, Malay ethnicity and bronchopulmonary dysplasia were significant risk factors associated with wheezing; (ii) longer duration of oxygen therapy during the neonatal period, seizures after the post-neonatal period and wheezing were significant risk factors associated with rehospitalization; and (iii) longer duration of oxygen therapy during the neonatal period was a significant risk factor associated with adverse neurodevelopmental outcome during the first year of life.

CONCLUSIONS

Compared with NBW infants, VLBW Malaysian infants had significantly higher risks of physical and neuro-developmental morbidities.

Outcome at 4 to 5 years of age in children recovered from neonatal chronic lung disease

Outcomes were compared for 31 very-low-birthweight children recovered from chronic lung disease and 31 very-low-birthweight controls. All children had been free of major abnormalities on neonatal cranial ultrasonography. At 4 to 5 years of age, children were examined by a pediatrician and tested by a psychologist who administered the Wechsler Preschool and Primary Scale of Intelligence-Revised. Despite similar medical outcomes, the children who had had neonatal chronic lung disease had lower Full-scale IQs (median 83 vs 87) and Performance IQs (79 vs 90). Median Verbal IQ was similar in the two groups (85 vs 87). A higher proportion of children who had had chronic lung disease had Full-scale IQ < 70 (8/31 [26%] vs 1/31 [3%]) and Performance IQ < 70 (8/31 [26%] vs 0/31). These effects persisted after adjustment for confounding factors.

Respiratory morbidity in preschool children born prematurely. Relationship to adverse neonatal events

Respiratory morbidity, recurrent cough and/or wheeze and lung function abnormalities are common even outside infancy in preschool children born prematurely. Throughout the first 5 years of life, adverse neonatal events such as immaturity at birth and a requirement for prolonged respiratory support are significantly associated with positive symptom status. In the older preschool child, however, there is some evidence to suggest that other factors, such as a family history of atopy, may be equally important. The development of recurrent symptoms even at 4 years of age can be predicted accurately from the results of lung function measurements made in infancy, and hopefully such data will facilitate the introduction of effective intervention strategies. Lung function abnormalities are more marked in symptomatic patients and, in older children, seem to reflect increased airway responsiveness rather than having a significant relationship to adverse neonatal events. The hospital readmission rate for respiratory disorders, however, is certainly adversely affected by extremely low birthweight and neonatal chronic lung disease, as well as current symptom status. These data highlight that strategies to reduce extremely premature delivery and its consequences should favourably influence respiratory morbidity in preschool children.