Low Birth Weight Survivors Research Articles

Extremely low birthweight infants at 3 years: A developmental profile

This study documents the neurodevelopmental outcome at 3 years of 52 of 55 extremely low birthweight (ELBW) survivors (survival rate 49%) born in a tertiary maternity centre from July 1985 through December 1988, and examines more closely the developmental profile of the neurologically normal survivors. At 3 years, 6 (12%) children had severe neurodevelopmental impairment (severe cerebral palsy, blindness, deafness or a General Quotient (GQ) < 70 on the Griffiths Scales), 11 (21%) had mild to moderate impairment and 35 (67%) had no neurosensory impairment and normal development (GQ > or = 85). Significant risk factors for severe impairment were stage 3 or 4 retinopathy of prematurity (odds ratio [OR] 21.5), treatment with postnatal steroids (OR 21), grade III or IV intraventricular haemorrhage (OR 11) and supplemental oxygen at 'term' (OR 6.4). The developmental profile of the 35 neurologically normal children revealed a significant weakness in eye and hand coordination skills and a relative strength in hearing and speech skills. Early recognition of this developmental profile may allow implementation of more appropriate preschool programmes for ELBW children.

Respiratory Health and Lung Function in 8-Year-Old Children of Very Low Birth Weight: A Cohort Study

In comparison with a cohort of normal birth weight children, those of very low birth weight (less than 1501 g birth weight) had more wheezing illnesses and hospital readmissions for respiratory problems in the first 2 years of life; from 2 years to 8 years of age respiratory health was unrelated to birth weight. Lung function measurements at 8 years of age in very low birth weight children were similar to expected values; few children had severely abnormal lung function. On univariate analyses, forced vital capacity (FVC) and forced expired volume in 1 second (FEV1), but not flow rates, were lower in children who had survived bronchopulmonary dysplasia. However, the univariate analyses were misleading, because bronchopulmonary dysplasia occurred more frequently with lower birth weight, and lower birth weight in turn was strongly related to reduced FVC and FEV1. After adjusting for birth weight and other potential confounding variables, FVC and FEV1 were unrelated to bronchopulmonary dysplasia, and to neonatal ventilation. Flow rates were largely uninfluenced by perinatal events, but were reduced in children with asthma or recurrent bronchitis at 8 years of age. Passive smoking was unrelated to lung function at 8 years of age. However, the effects of passive or active smoking, or perinatal events, on respiratory function or health beyond 8 years of age in very low birth weight survivors remain to be determined.

Survival and cerebral palsy in low birthweight infants: implications for perinatal care.

Whilst only about a third of all cerebral palsy occurs in children who had been of low birthweight, recent increases in the survival of low and very low birthweight infants have coincided with significant increases in the numbers of cerebral palsy children amongst them. This paper analyses data from the Western Australian Cerebral Palsy Register and from the Maternal and Child Health Research Data Base for stillbirths, neonatal deaths and survivors to address the issues of increased survival, cerebral palsy and timing of brain damage. The analysis is inconclusive but suggestive that both antenatal and postnatal complications are important in the increases in cerebral palsy in low birthweight infants. The good news is that this means that a certain proportion of postnatally damaged low birthweight survivors could possibly be prevented by better neonatal care. The bad news is that the remaining proportion have probably received their damage well before delivery and the possibilities for prevention are still remote. Further studies of low birthweight infants with cerebral palsy are urgently required. They should include antenatal factors, investigating the various aetiological pathways to preterm birth, randomised controlled trials of neonatal interventions and searching for better neonatal predictors of brain damage.

Very Low Birth Weight Outcomes

To the Editor.— The authors of the National Institute of Child Health and Human Development report on neonatal care1 found "important" variations among neonatal intensive care units in philosophies of treatment, methods of treatment, and short-term outcomes. In a recent meta-analysis of follow-up studies,2 researchers document a similarly haphazard approach to the long-term evaluation of very low birth weight survivors. Until randomized controlled clinical trials validate the safety and efficacy of neonatal therapies, and until long-term outcomes are assessed accurately, the treatment of very low birth weight infants should be declared experimental.

Cognitive abilities and school performance of extremely low birth weight children and matched term control children at age 8 years: A regional study

The intellectual, psychoeducational, and functional status of a regional cohort of extremely low birth weight (ELBW) survivors who weighed 501 to 1000 gm at birth (n = 143) and who were born between 1977 and 1981 was compared with that of control children born at term (n = 145) who were matched for gender, age, and social class. One hundred twenty-nine ELBW survivors (90%) were available; their mean birth weight was 839 +/- 124 gm and mean gestational age 27 +/- 2.1 weeks, and 48 of them weighed less than or equal to 800 gm at birth. Both ELBW and control groups were tested at a mean unadjusted age of 8 years; 113 of 129 ELBW children completed the full test battery, eight blind children had other tests, and eight were not testable. The mean Full Scale IQ (Wechsler Intelligence Scale for Children--Revised) was 91 +/- 16 for ELBW children and 104 +/- 12 for control children (p less than 0.0001). Between 8% and 12% of the ELBW group scored in the "abnormal" range (less than or equal to -2 SD) on the Wechsler IQ and subtests, compared with 1% to 2% of the control group. The ELBW group did less well on the reading, spelling, and mathematics tests (Wide Range Achievement Test--Revised less than or equal to -2 SD: ELBW = 20% to 28%; control = 3% to 10%). The motor performance of the ELBW group (Bruininks-Oseretsky Test of Motor Proficiency less than or equal to -2 SD: ELBW = 20%; control = 1%) and their visual-motor integration (Beery Developmental Test of Visual-Motor Integration less than or equal to -2 SD: ELBW = 21%; control = 6%) were also poorer. Exclusion of 19 ELBW children with neurologic impairments or an IQ less than or equal to 70 or both did not result in significant improvement in Wechsler or achievement measures. Approximately 15% of the ELBW cohort performed in the abnormal range on the Vineland Adaptive Behavior Scales, compared with none of the control group. Although approximately two thirds of the ELBW group were performing in the normal range on intellectual measures, comparison with the control group suggests that, as a group, ELBW children were significantly disadvantaged on every measure tested.

Neurodevelopmental Outcome, Growth And Health Of Extremely Low‐Birthweight Survivors: How Soon Can We Tell?

A three-year cohort of extremely low-birthweight (ELBW, less than 1000g) survivors born between 1st January 1979 and 31st December 1981 were followed prospectively at one, two and five years of age, corrected for preterm birth. 57 of 110 infants survived, and 53 children were still alive at five years. The diagnoses of cerebral palsy, blindness, deafness and developmental delay fluctuated markedly according to age at developmental assessment. Although 13 of the 53 children were found to have impairments at five years, only seven were identified at one year, while 17 were identified at two years. In relation to the five-year assessment, impairments were underestimated at one year and developmental delay was overestimated at two years, which suggest that valid and reliable estimation of adverse neurodevelopmental sequelae among ELBW survivors may not be possible until school-age.

Cerebral palsy in very low birthweight infants.

Eighty one very low birthweight survivors with cerebral palsy were matched with controls by sex, gestational age, and place of birth. Using discriminant analysis, the perinatal profiles for infants with cerebral palsy and their controls were shown to differ significantly. When infants with various types of cerebral palsy were analysed with their controls the discriminating variables differed. Diplegic infants could be differentiated from controls on antenatal variables alone, but significant discrimination of hemiplegic and quadriplegic infants required the addition of postnatal variables. Cranial ultrasound appearances differed appreciably between types of cerebral palsy. Future studies should differentiate between types of cerebral palsy and include ultrasound data. Cerebral palsy in very low birthweight infants is unlikely to prove a useful outcome indicator for neonatal intensive care.

Morbidity Is Decreased by Neonatal Intensive Care

To the Editor.— A recent annotation by "Student" (Pediatrics 1989;83:180) is a quote from a letter from Johnson and MacFarlane in The Lancet of July 16, 1988, stating that, in geographically defined populations, a reduction in the level of morbidity among low birth weight survivors has not yet been demonstrated. We believe that there are, however, some encouraging signs. There is a report from the Federal Republic of Germany1 describing a reduction in the frequency of neurologic sequelae in a very low birth weight population, born between 1977 and 1983, from a neonatal intensive care unit.

DECLINE IN MORBIDITY OF LOW BIRTH WEIGHT SURVIVORS NOT YET SHOWN

Hundreds of "follow-up studies" have been published since the early days of neonatal intensive care, and each represents a considerable cost in terms of time and resources. It is unfortunate that only a mere handful of these are based on geographically defined populations since [meaningful] comparisons . . . can only be made through such studies. To date these show that there has been no real change in the level of morbidity among low birthweight survivors. The "important reduction in morbidity," which we would all welcome, is yet to be demonstrated.

Systemic candidiasis and pneumonia in preterm infants

Twenty-two preterm infants with systemic candidiasis are reported, of which seven cases were presumed to be antenatally acquired and 15 postnatally acquired. All except one were of very low birthweight. Fifteen infants had positive cultures of blood, cerebrospinal fluid or urine and seven had candida pneumonia only. Clinical features included general instability, respiratory deterioration and a necrotizing enterocolitis-like presentation. The incidence of leukocytosis, shift to the left, eosinophilia and thrombocytopenia were not different from those with bacterial infection. The diagnosis was made after death in two infants. In the remaining 20 infants, treatment was initiated between 5 and 97 days of age, with a median delay of 4 days after the first positive cultures were taken. Complications of amphotericin and 5-flucytosine therapy which developed in five infants resolved on cessation of treatment. The mortality rate was 18% and impairment rate among the 17 very low birthweight survivors was 18%. A high index of suspicion is required for systemic candidiasis, especially in infants of less than 1000 g birthweight. If recognized early, effective and safe antifungal therapy is possible with favourable short- and long-term outcome.

Cerebral palsy in low-birthweight infants. II. Spastic diplegia: associations with fetal immaturity.

Twenty children with spastic diplegia were identified by clinical assessment among a representative cohort of 1048 survivors with a birthweight of 2000g or less. Data from hospital case-records were used to investigate which perinatal conditions might differentiate infants with diplegia from other low-birthweight survivors. Even allowing for a strong association with lower gestational age, diplegic children were more likely to have suffered respiratory disease, necrotising enterocolitis and fits in the neonatal period, than children without cerebral palsy. Among preterm infants, diplegia differed from hemiplegia mainly in a lack of significant association with recorded maternal characteristics and markers of intrapartum stress. Important determinants of diplegia were not identified, but the results suggest that infants born both immature and relatively immature for their gestational age have the highest risk of diplegia. Factors that influence the rate of fetal development may be implicated in the aetiology of diplegia in both preterm and fullterm infants.

Cerebral palsy in low-birthweight infants. I. Spastic hemiplegia: associations with intrapartum stress.

Children with and without spastic hemiplegia were identified among a representative sample of 1048 low-birthweight survivors by clinical assessment after three years of age. The hypothesis that hemiplegia was predetermined at birth was tested by estimating the probability of hemiplegia for each infant by logistic regression analysis, using data from hospital records on conditions known at the time of birth. 16 of 42 children with cerebral palsy had spastic hemiplegia. Allowing for the lower birthweights of hemiplegic children, increased prevalence was associated with previous reproductive loss, breech vaginal delivery, later birth-order, prolonged second stage of delivery, emergency caesarean section, and low Apgar scores. These variables identified correctly most children as having a higher or lower estimated probability of hemiplegia. Hemiplegia was also associated with prolonged respiratory disease and intraventricular haemorrhage. In this population it is likely that intrapartum events were closely related to the pathogenesis of hemiplegia; their effects may have been mediated by postnatal events.

Very low birth weight survivors:: Authors' reply

Very low birth weight survivors:: Authors' reply

Very low birthweight survivors: illness and rehospitalisation in the first fifteen months of life

Very low birthweight survivors: illness and rehospitalisation in the first fifteen months of life

Regional neonatal intensive care: bias and benefit.

Among very low birthweight infants born to residents of Merseyside in 1979-81 those booked at or transferred in utero to the regional unit were more likely to survive than those born elsewhere in the region. A study was carried out to determine whether the increased survival rate was attributable to better care or differences in the babies treated at the unit, or both. Four subpopulations were defined by district of maternal residence to obtain fairly comparable samples. Survival to 2 years increased as proportions treated at the regional unit increased, this "dose-response" effect being most pronounced among the smallest infants. Despite less favourable social state infants from the district housing the regional unit were apparently in the best condition at birth; had been managed most actively before, at, and after birth; and were the most likely to survive. This increased survival, however, was associated with a marginally significant increase in prevalence of major impairments. These data underline the need for routine surveillance of large representative samples of low birthweight survivors.

Very low birthweight survivors: illness and readmission to hospital in the first 15 months of life.

Revue portant sur 57 nouveau-nes (non jumeaux) pesant moins de 1500 g a la naissance. 26 d'entre eux presentent une morbidite importante pendant les 15 premiers mois: 19 souffrent d'infections respiratoires serieuses, necessitant souvent des rehospitalisations. 4 sont hospitalises pour d'autres maladies. 5 sont hospitalises pour des maladies benignes

Relationship between two-year behaviour and neurodevelopmental outcome at five years of very low-birthweight survivors.

A prospective five-year follow-up of survivors of very low birthweight (less than or equal to 1500 g) born in 1979 was carried out at the Queen Victoria Medical Centre, Melbourne, between 1980 and 1985. Of the 57 children reported here, 23 had been identified during psychological testing at two years as having an attention deficit disorder (ADD). Although the number with ADD at five years had decreased to 18, the two-year diagnosis was retained to test its predictive value for outcome at school-age. Children with ADD at two years differed significantly from their peers at five years in verbal, performance and full-scale IQ and had significantly more minor physical disabilities. They also had poorer visual acuity, more tremor, poorer balance, and more deviations with arms extended in pronation. The ADD children had more minor, though chronic, physical illnesses such as tonsillitis and serous otitis media. Their mothers expressed greater concern than the other mothers about hearing and behaviour. The ADD children were rated as significantly more aggressive, difficult to manage and less able to cope with frustration. As a predictor of five-year IQ, behaviour at two years was more powerful than social class. ADD discriminated a subgroup of very low-birthweight children whose lower IQ and multiple physical, neurological and behavioural difficulties place them at very high risk of learning disabilities.

Why do so many small infants develop an inguinal hernia?

Prevalence and incidence of inguinal hernia in a representative sample of low birthweight survivors were determined by tracing children at 3 years of age. Prevalence was examined in relation to perinatal factors recorded in hospital case notes, using a logistic regression model to allow for confounding variables. Of the 1074 two year survivors, 995 (93%) were assessed. Seventeen per cent of 497 boys and 2% of 498 girls had a hernia by 3 years of age, a total cumulative prevalence of 9.2%: it was significantly increased by lower birth weight, male sex, neonatal intravenous feeding, and lack of respiratory disease. Neonatal illnesses were otherwise not associated with herniation, and most infants were well when they presented. Peak incidence was at the expected full term of gestation. Bilateral hernias were increasingly more common than unilateral hernias at lower gestational ages. It is proposed that causes of increased abdominal pressure in healthy neonates are important causes of herniation during a critical period of inguinal development.

Status at two years in 121 very low birth weight survivors related to neonatal intraventricular haemorrhage and mode of delivery.

All 121 infants with birthweight less than or equal to 1500 g (VLBW) discharged from our department through an 18-month period were followed up at two years of age. All but 10 infants were examined by cranial ultrasound scanning in the neonatal period. Six had died after discharge; and of these two had severe brain damage following neonatal intraventricular haemorrhage. Twelve children had definite neuromotor abnormality; of these, the nine children with spastic types of cerebral palsy had all been delivered vaginally. Of the remaining children, one half had at least one neurodevelopmental symptom suggesting perinatal brain damage. Outcome was associated to neonatal intraventricular/subependymal haemorrhage when complicated by ventricular dilatation. Outcome in children with simple haemorrhage was similar to that in children without haemorrhage. The association between outcome and haemorrhage was considerably reduced by simultaneously considering the associations of gestational age at birth and the use of mechanical ventilation in the neonatal period. Head circumference at follow-up was greatest in those children with haemorrhage complicated by ventricular dilatation, when adjusted for actual body weight, birth weight, and gestational age at birth.

Disabilities in survivors of low birthweight.

A study of those survivors weighing 2000 g or less at birth born to residents of the South East Thames Regional Health Authority in 1970, '71, and '73 was carried out by abstracting data from health visitors' and school health records. Some postnatal information was available for 78% of the children. Prevalences of reported impairments in relation to birthweight were 20% in babies of 1500 g or less, 13% in the group weighing 1501 to 1750 g, and 11% for those of 1751 to 2000 g. Only half the impairments in the first group were likely to be seriously disabling, and only a fifth were of obvious prenatal origin. In the heaviest group, about 3% were likely to become severely disabled, but in over two fifths with impairment, this was likely to be of prenatal origin and therefore more difficult to prevent. This factor together with the larger number of survivors of birthweight 1751 to 2000 g than of 1500 g or less, indicate that an increase in impairments may be seen in the heavier group if their mortality continues to fall.