Development and characterization of seven polymorphic microsatellite loci in Bembidion atrocaeruleum (Coleoptera: Carabidae)

We isolated seven polymorphic microsatellite loci from a ground beetle (Bembidion atrocaeruleum, Coleoptera, Carabidae (Stephens, 1826)) associated with naturally and regularly disturbed floodplain habitat in northwest Europe. Loci were tested on 157 individuals collected from five distinct habitat patches across two adjacent drainage basins in Wales, United Kingdom, to assess their potential for revealing population structure across a relatively short spatial extent. Alleles per locus ranged from 4 to 12. For a central representative population, expected heterozygosity ranged from 0.23 to 0.78 (mean: 0.63), and observed heterozygosity ranged from 0.16 to 0.94 (mean: 0.56). Analysis of molecular variance indicated significant structure among populations, even when one locus potentially containing null alleles was removed. These loci have the potential to aid the study of dispersal mechanisms of this important riparian species along and between river corridors, a recurring question in floodplain conservation studies. In addition, given the diversity of the Bembidion genus, they may have utility in the study of sister species.

Responses to river inundation pressures control prey selection of riparian beetles

Background

Riparian habitats are subjected to frequent inundation (flooding) and are characterised by food webs that exhibit variability in aquatic/terrestrial subsidies across the ecotone. The strength of this subsidy in active riparian floodplains is thought to underpin local biodiversity. Terrestrial invertebrates dominate the fauna, exhibiting traits that allow exploitation of variable aquatic subsidies while reducing inundation pressures, leading to inter-species micro-spatial positioning. The effect these strategies have on prey selection is not known. This study hypothesised that plasticity in prey choice from either aquatic or terrestrial sources is an important trait linked to inundation tolerance and avoidance.

Method/Principal Findings

We used hydrological, isotopic and habitat analyses to investigate the diet of riparian Coleoptera in relation to inundation risk and relative spatial positioning in the floodplain. The study examined patch scale and longitudinal changes in utilisation of the aquatic subsidy according to species traits. Prey sourced from terrestrial or emerging/stranded aquatic invertebrates varied in relation to traits for inundation avoidance or tolerance strategies. Traits that favoured rapid dispersal corresponded with highest proportions of aquatic prey, with behavioural traits further predicting uptake. Less able dispersers showed minimal use of aquatic subsidy and switched to a terrestrial diet under moderate inundation pressures. All trait groups showed a seasonal shift in diet towards terrestrial prey in the early spring. Prey selection became exaggerated towards aquatic prey in downstream samples.

Conclusions/Significance

Our results suggest that partitioning of resources and habitat creates overlapping niches that increase the processing of external subsidies in riparian habitats. By demonstrating functional complexity, this work advances understanding of floodplain ecosystem processes and highlights the importance of hydrological variability. With an increasing interest in reconnecting rivers to their floodplains, these invertebrates represent a key functional element in ensuring that such reconnections have demonstrable ecological value.

Analysis of threshold-type behaviour in mathematical models of the intrusion of a novel macroparasite in a host colony

Macroparasites include worms, ticks, mites, bugs and fleas. These parasites are well known to induce morbidity effects including a reduction in the hosts' reproductive output and survival. An important scenario is the introduction of a new macroparasite into an established host population which may be caused by the climate change and by the transport of domestic animals. The aim of the article is to demonstrate an interesting feature of this scenario using a mathematical model with four dimensionless parameters. Six possible scenarios of introducing a new macroparasite into a host colony, ranging from the elimination of the new pathogen, through guaranteed host and parasite coexistence, to the collapse of the host colony are distinguished. The threshold surfaces in the space of parameters which separate the different scenarios are found. Some special limit cases are discussed.

Longitudinal correlates of the persistence of irregular eating from age 5 to 14 years

AIM

To report the stability of parent-perceived child irregular eating from 6 months to 14 years of age and to investigate a predictive model inclusive of child and parent factors.

METHODS

Of the 7223 singleton children in a birth cohort, 5122 children were re-interviewed at 5 years and 4554 for the 14-year analysis. Information was obtained from structured interviews including questions answered by parents of the child at birth, 6 months, 5 years and 14 years; and by teenagers at age 14 years and from physical measures of the child. The mother's perception that the child was an irregular eater at age 14 years was the major outcome variable of interest.

RESULTS

Approximately 40% of irregular eaters at age 5 will still be irregular eaters at age 14 years. This was not related to maternal education or socio-economic class. Significant at multivariate analysis were infant feeding problems and the children's ability to regulate their sleep and mood. Significant maternal factors were greater age, not feeling positive about the baby and persistent maternal anxiety during the child's early years.

CONCLUSION

Irregular eating behaviour displays considerable continuity from childhood to mid-adolescence. Independent contributions to this behavioural phenotype include child biological and psychological factors and maternal anxiety during the child's early years.

Maternal smoking during and after pregnancy and lung function in early adulthood: a prospective study

BACKGROUND AND AIMS

There is a paucity of evidence about whether exposure to antenatal smoking impacts on offspring's lung function in early adulthood. This study aimed to examine whether (1) in utero exposure to maternal smoking is related to poorer respiratory functioning in early adulthood; (2) the impact of prenatal smoking is independent of postnatal maternal smoking; and (3) the link between prenatal smoking and a young adult's lung function is explained by the child's birth weight, smoking or history of asthma.

METHODS

Data were from a 21-year follow-up of mothers and their children recruited into the Mater-University of Queensland Study of Pregnancy, a longitudinal prebirth cohort. The study is based on 2409 young adults (1185 males and 1224 females) who had prospective data available on respiratory function at 21 years and maternal smoking during and after pregnancy. A Spirobank G spirometer system was used to measure forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)) and forced expiratory flow between 25% and 75% of FVC (FEF(25-75)).

RESULTS

In utero exposure to maternal smoking was associated with a reduction in FEV(1) and FEF(25-75) in males (regression coefficient, -0.16; 95% CI, -0.30 to -0.02), after accounting for maternal smoking after pregnancy. At least part of the effect of in utero smoking on young adults' lung function was explained by the child's birth weight and subsequent asthma.

CONCLUSIONS

Adverse effects of antenatal smoking on development of airway growth may persist into early adulthood. Gender differences noted in this longitudinal cohort need to be explored further.

Increasing body mass index from age 5 to 14 years predicts asthma among adolescents: evidence from a birth cohort study

BACKGROUND

Obesity and asthma are common disorders, and the prevalence of both has increased in recent decades. It has been suggested that increases in the prevalence of obesity might in part explain the increase in asthma prevalence. This study aims to examine the prospective association between change in body mass index (BMI) z-score between ages 5 and 14 years and asthma symptoms at 14 years.

METHODS

Data was taken from the Mater University Study of Pregnancy and its outcomes (MUSP), a birth cohort of 7223 mothers and children started in Brisbane (Australia) in 1981. BMI was measured at age 5 and 14 years. Asthma was assessed from maternal reports of symptoms at age 5 and 14 years. In this study analyses were conducted on 2911 participants who had information on BMI and asthma at both ages.

RESULTS

BMI z-score at age 14 and the change in BMI z-score from age 5 to 14-years were positively associated with asthma symptoms at age 14 years, whereas BMI z-score at age 5 was not associated with asthma at age 14. Adjustment for a range of early-life exposures did not substantially alter these findings. The association between change in BMI z-score with asthma symptoms at 14 years appeared stronger for male subjects compared with female subjects but there was no statistical evidence for a sex difference (P=0.36).

CONCLUSIONS

Increase in BMI z-score between age 5 and 14 years is associated with increased risk of asthma symptoms in adolescence.

Is being overweight associated with behavioural problems in childhood and adolescence? Findings from the Mater-University study of pregnancy and its outcomes

AIMS

To examine the associations between being overweight and behavioural problems at ages 5 and 14.

METHODS

Birth cohort study of 2875 individuals who were born in Brisbane between 1981 and 1984 and who were followed up at ages 5 and 14 years. Behavioural problems were defined as scoring above the 90th centile on Achenbach's child behavioural checklist.

RESULTS

In cross-sectional analyses there was no association between being overweight and behavioural problems in either females at age 5. At age 14 females who were overweight were more likely than those who were normal weight to experience behavioural problems. However, there was no association between being overweight and behavioural problems at age 14 among males. The prevalence of behavioural problems increased linearly across the distribution of body mass index in females at age 14. In prospective analyses, among participants who had no behavioural problems at age 5, there was no association between being overweight at age 5 and behavioural problems at age 14 in either sex. Females who were overweight at age 5 and normal weight at age 14 had reduced odds of behavioural problems at age 14.

CONCLUSIONS

Among adolescent females there is a positive linear association between body size and behavioural problems. However, no such association was found in adolescent males, or in either sex at age 5 years, and in prospective analyses being overweight at age 5 was not associated with behavioural problems in either sex at age 14.

Family and early life factors associated with changes in overweight status between ages 5 and 14 years: findings from the Mater University Study of Pregnancy and its outcomes

OBJECTIVE

To describe different patterns of overweight status between ages 5 and 14 y and examine the role of modifiable family and early life characteristics in explaining different patterns of change between these two ages.

DESIGN

A population-based prospective birth cohort.

SUBJECTS

A total of 2934 children (52% males) who were participants in the Mater-University study of pregnancy, Brisbane, and who were examined at ages 5 and 14 y.

MAIN OUTCOME MEASURES

Four patterns of change in overweight/obesity status between ages 5 and 14 y: (i) normal at both ages; (ii) normal at 5 y and overweight/obese at 14 y; (iii) overweight/obese at 5 y and normal at 14 y; (iv) overweight/obese at both ages.

RESULTS

Of the 2934 participants, 2018 (68.8%) had a normal body mass index (BMI) at ages 5 and 14 y, 425 (14.5%) changed from a normal BMI at age 5 y to overweight or obese at age 14 y, 175 (6.0%) changed from being overweight or obese at age 5 y to normal weight at age 14 y and 316 (10.8%) were overweight or obese at both ages 5 and 14 y. Girls were more likely to make the transition from overweight or obese at age 5 y to normal at 14 y than their boy counterparts. Children whose parents were overweight or obese were more likely to change from having a normal BMI at age 5 y to being overweight at 14 y (fully adjusted RR: 6.17 (95% CI: 3.97, 9.59)) and were more likely to be overweight at both ages (7.44 (95% CI: 4.60, 12.02)). Birth weight and increase in weight over the first 6 months of life were both positively associated with being overweight at both ages. Other explanatory factors were not associated with the different overweight status transitions.

CONCLUSIONS

Parental overweight status is an important determinant of whether a child is overweight at either stage or changes from being not overweight at 5 y to becoming so at 14 y.

Early childhood factors influencing health-related quality of life in adolescents at 13 years

OBJECTIVE

To understand the relationship of health-related quality of life (HR-QOL) to early life experience.

METHODOLOGY

Eight thousand five hundred and fifty-six women enrolled in a prospective study at their first antenatal clinic visit. At 13 years, of 5345 women remaining, a consecutive sample of 901 mother/child pairs provided data on adolescent HR-QOL using the Child Health Questionnaire-Parent Report form (CHQ-PF50) and the Dartmouth COOP Functional Assessment Charts for Adolescents. The CHQ-PF50 yielded physical (PHS) and psychosocial (PSS) summary scores. We examined the relationship between health-related QOL and early childhood predictive variables.

RESULTS

PHS was related to gestation, maternal health symptoms in pregnancy, maternal anxiety at 6 months, child health and hours of childcare at 5 years (P < 0.05). PSS was related to maternal age at index visit, maternal attitude to pregnancy, maternal satisfaction with care giving and maternal depression at 6 months, and child health and behaviour problems at 5 years (internalizing and social/attentional/thought (SAT) domains) (P < 0.05). Findings from adolescent self-reports were similar.

CONCLUSIONS

This study has identified a number of early childhood determinants of adolescent HR-QOL. These findings add to evidence of the effects of early adversity on the developmental pathways of children and support the need for effective early intervention.

Psychoeducational outcome at school age of preterm infants with bronchopulmonary dysplasia

OBJECTIVE

To investigate the cognitive performance and educational attainment at school-age of children with bronchopulmonary dysplasia (BPD), compared with a preterm control group of children.

METHODS

Seventy preterm infants with BPD and 61 birth weight matched controls were prospectively followed-up to school-age. The Weschler Intelligence Scale for Children - III (WISC), the Wide Range Achievement Test (WRAT) and the Developmental Test of Visual Motor Integration (VMI) were administered. The results were compared between the two groups and multiple regression analyses were performed to determine the effect of confounding variables.

RESULTS

The children in the BPD group performed less well on the Full Scale IQ (mean 86.7 vs 93.5; 95% CI, 1.9-11.7), Verbal IQ (mean 87.1 vs 94.1; 95% CI, 2.0-12.0) and the Performance IQ (mean 88.6 vs 95.2; 95% CI, 2.0-11.2) of the WISC, the reading component of the WRAT (mean 93.8 vs 98.9; 95% CI, 0.3-9.8) and the VMI (mean 88.9 vs 93.3; 95%, CI 1.1-7.8). Despite controlling for social and biological variables, statistical differences persisted for Full Scale and Verbal IQ and reading. A Verbal IQ >1 SD below the mean was found in 41% of BPD children compared to 21% of controls, while on the reading component of the WRAT a greater proportion of BPD children also had scores>1 SD below the mean.

CONCLUSION

Impaired psychoeducational performance was found in preterm children with BPD compared to controls, especially in the areas of language abilities and reading skills. This supports a greater need for special educational services and counseling for parents for these children.

Early adolescent smoking and a web of personal and social disadvantage

OBJECTIVE

To examine concurrent physical, educational, behavioural, social and family factors associated with cigarette smoking in adolescents at 14 years.

METHODOLOGY

This study reports cross-sectional data on 14-year-old adolescents and their mothers, drawn from a prospective cohort study commencing at the time of the first antenatal visit. At 14 years, 5247 adolescents completed questionnaires on current cigarette smoking. Adolescents and mothers completed health, psychological, school and social questionnaires relating to the youth. A total of 3864 adolescents were assessed physically, and undertook the Wide Range Achievement Test (WRAT) and Ravens Progressive Matrices Test.

RESULTS

Cigarette smoking at 14 years was associated with externalizing and internalizing behaviour problems, school suspension, contact with children's services and alcohol/illicit drug use. Apart from internalizing behaviour problems, these problems were more prevalent in boys. Poor school performance on maternal/adolescent reports was associated with increased smoking quantity for both genders, though WRAT scores were only decreased in male smokers. The Ravens Progressive Matrices Test scores were lower for boys with greater smoking quantity. The trend was less marked in girls. Body mass index and exercise frequency were not associated with cigarette smoking at 14 years, though girls who smoked had a higher reported prevalence of asthma. Parental smoking, marital conflict, maternal depression, lower income, and mothers aged in their teens and with a lower level of education at the time of this pregnancy were also positively associated with adolescent tobacco use.

CONCLUSION

Findings of this study indicate that cigarette smoking, at this critical time of smoking initiation, is associated with a broad spectrum of personal and social disadvantage that needs to be considered in intervention strategies.

Association of bullying with adolescent health-related quality of life

OBJECTIVE

To examine the relationship between being bullied and health-related quality of life (HR-QOL) in adolescence.

METHODOLOGY

Subjects were a cohort of 805 adolescents with a mean age of 13.6 years (standard deviation 0.2 years). An adolescent questionnaire elicited the frequency of being bullied. HR-QOL was measured using the Child Health Questionnaire - Parent Report Form (CHQ-PF50) and Dartmouth COOP Functional Health Assessment Charts for Adolescents.

RESULTS

Thirty-six per cent of boys and 38 per cent of girls reported being bullied at least weekly. Adolescent psychosocial HR-QOL was inversely related to frequency of being bullied, while physical HR-QOL was not related.

CONCLUSION

Peer bullying is an important determinant of adolescent HR-QOL with a negative impact on psychosocial well-being.

Non-anaemic iron deficiency identified by ZPP test in extremely premature infants: prevalence, dietary risk factors, and association with neurodevelopmental problems

INTRODUCTION

The aims of this study were to determine, in a cohort of extremely premature infants, the prevalence of iron deficiency identified by zinc protoporphyrin/heme ratio (ZPP) testing, and its association with neurodevelopmental problems and dietary risk factors for iron deficiency.

METHODS

Infants of less than 29 weeks' gestation or less than 1000 g birth weight were studied prospectively at a multidisciplinary follow-up clinic. Assessments were made at a corrected age of either 12 months (n=72) or 2 years (n=69). Physical examination, Griffiths Developmental Scale, and neurosensory-motor assessment were administered, information on diet and behaviour was obtained by questionnaire, and a fingerprick ZPP ratio was performed to identify iron deficiency.

RESULTS

18.4% of infants had positive ZPP tests. There was no significant association between a positive ZPP test result and dietary risk factors, or symptoms of lethargy, irritability or poor attention. In children without cerebral palsy, there was no difference on Griffiths scores or neurosensory-motor assessment between ZPP-positive and ZPP-negative groups. The diagnosis of cerebral palsy (n=12) was significantly associated with both a positive ZPP test and a lower Griffiths general quotient (GQ) score.

CONCLUSIONS

Iron deficiency occurs commonly in extremely low birth weight (ELBW) children in early childhood, and is not predicted by dietary risk factors. The prevalence of iron deficiency is increased in ELBW children with cerebral palsy. Non-anaemic iron deficiency (NAID) does not impair development or significantly affect behaviour of ELBW subjects who do not have cerebral palsy.

Low alcohol preference among the "high alcohol preference" C57/BL10 mice; factors affecting such preference

The effects of age, ethanol concentration and minor stress on the variation in alcohol preference of C57 strain mice were determined. In two bottle choice tests, an older population of mice contained slightly more low-preference mice than a younger population. A wide range of ethanol preference was consistently seen in young mice for 8% and 6% ethanol, but the previously reported biphasic pattern of distribution was revealed only with 8% ethanol. Very few animals showed high preference for concentrations of 10% or 12% ethanol. Moving low alcohol preference mice to a new location (but not repeated cage changing or ultrasonic noise) significantly increased the alcohol preference. Exploratory locomotor activity did not correlate with the subsequent alcohol consumption. Blood and brain alcohol concentrations showed that the differences in alcohol preference were not due to differences in metabolism of ethanol. The C57 strain mice with low preference for alcohol provides a valuable model for the study of the effects of minor stress on alcohol consumption.

Effects of intraperitoneal injections of saline on the alcohol and sucrose consumption of C57/BL10 mice

RATIONALE

To determine the effects of multiple saline injections on alcohol drinking by male and female C57/BL10 mice with low preference for alcohol.

OBJECTIVE

An investigation of the effects of multiple saline injections on alcohol consumption, with a comparison of corresponding effects on sucrose consumption.

METHODS

The effects of a range of injection schedules on preference for 8% alcohol, or 1% sucrose, compared with tap water, were measured in two-bottle choice tests.

RESULTS

The multiple saline injection schedule significantly increased the alcohol preference, even when no alcohol was available during the injection period. The actual administration of fluid was not necessary for the increase in alcohol preference, since sham injections without fluid administration also increased alcohol preference. A single injection of saline did not alter the alcohol preference 3 weeks later. Daily saline injections for 3 weeks did not alter the consumption of the dilute sucrose solution. In the population of mice used, the preference for sucrose over water was found to follow a biphasic distribution, similar to that reported earlier in these mice for alcohol preference, but there was no correlation between alcohol preference and sucrose preference.

CONCLUSIONS

The results suggest that lasting changes in the areas of the brain that specifically control alcohol intake are produced by repetition of a routine laboratory procedure.

Alterations in mesolimbic dopamine function during the abstinence period following chronic ethanol consumption

Previous work demonstrated that the locomotor stimulant actions of amphetamine, cocaine and nicotine were increased when these drugs were given during the abstinence phase after chronic ethanol consumption. These changes were seen at 6 days and at 2 months after cessation of alcohol. The present study examined neuronal alterations which might be related to these changes in behaviour. Markedly reduced spontaneous firing rates of dopaminergic cells in the ventral tegmental area (VTA) in midbrain slices were seen 6 days into the abstinence period after cessation of chronic ethanol consumption, but by 2 months the firing rates had returned to control values. Increased affinity of striatal receptors for the D1-like receptor ligand 3H-SCH23390, but no change in the receptor density, was found both at the 6 day and the 2 month intervals. The binding properties of striatal D2-like receptors, of D1-like and D2-like receptors in the frontal cerebral cortex, and the release of tritiated dopamine from slices of striatum or frontal cerebral cortex, were unchanged at 6 days and 2 months. It is suggested that the decreased neuronal firing leads to a persistent increase in sensitivity of D1-like receptors and that these changes could explain the increased effects of the other drugs of abuse.

Maternal antecedents for cerebral palsy in extremely preterm babies: a case-control study

The study aimed to identify significant antenatal risk factors for cerebral palsy (CP) among extremely preterm infants with a matched case-control design. Infants born between 1989 and 1996 at 24 to 27 weeks' gestation who survived to hospital discharge were evaluated: 30 with a proven diagnosis of CP at 2 years corrected for prematurity and 120 control children matched for gestational age without CP. Information on maternal obstetric risk factors and medication was obtained. Matched analyses were performed and odds ratios (OR) and 95% confidence intervals (CI) were calculated. An antenatal diagnosis of intrauterine growth restriction was associated with an increased risk of CP (OR 6.6; 95% CI 1.8 to 25.2), while maternal administration of corticosteroids was associated with a reduced risk of CP (OR 0.4; 95% CI 0.1 to 0.98). A high rate of placental histopathology was achieved but no relation between clinical or histological chorioamnionitis or funisitis and CP was demonstrated. Maternal preeclampsia was not associated with a statistically significant reduction in the risk of CP. It is concluded that a reduced risk of CP in extremely preterm infants is associated with the antenatal use of corticosteroids.

Serial transform optical correlator design principles

Optical correlators such as the 4f and VanderLugt optical systems have been an active area of research for many years; we refer to these types of optical system collectively as serial transform correlators (STCs). Despite being well known, misconceptions regarding the design of STCs are not uncommon. We show, for example, that one correlator configuration reported to suffer from a phase curvature problem in fact works correctly. We present and prove a simple set of rules to follow in the selection of a STC design that does not contain unnecessary constraints and that makes it easier to identify permissible optical systems. As examples, we discuss three representative types of correlator configuration, one of which is discussed in detail to highlight its practical advantages. A novel proof of the design rules is presented that does not depend on details such as what lenses or combination of lenses are used, what their focal lengths are, or what their locations are within the optical system. We also present a conventional Fourier optics proof.

Childhood neglect and cognitive development in extremely low birth weight infants: a prospective study

OBJECTIVE

To examine the relationship between child maltreatment and cognitive development in extremely low birth weight infants, adjusting for perinatal and parental risk factors.

METHODS

A total of 352 infants with birth weight of <1000 g were followed prospectively for 4 years. The data were analyzed with regard to perinatal and parental risk factors and referrals for suspected child maltreatment to government agencies. Perinatal risk factors included birth weight, gestation, gender, periventricular hemorrhage, ventricular dilation, home oxygen requirement, and necrotizing enterocolitis. Parental risk factors included maternal age, race, marital status, education, and hospital insurance status. Cognitive z scores were calculated at 1, 2, and 4 years, and head circumference z scores were calculated at birth, 2 years, and 4 years.

RESULTS

Fifteen percent of infants were referred to child protective services for suspected child maltreatment. The adjusted general cognitive index at 4 years was significantly reduced in infants who were referred for neglect (-17.6; 95% confidence interval: -3.3, -31.9). Infants whose neglect was substantiated had a progressive decline in their cognitive function over time (cognitive z scores: -0.97, -1.37, and -2.05 standard deviations at 1, 2, and 4 years, respectively), compared with non-neglected infants (z scores: -0.04 to -0.36). They had a significantly smaller head circumference at 2 and 4 years but not at birth (adjusted z score at 4 years: -0.812; 95% confidence interval: -0.167, -1.458). Perinatal risk factors and physical disability were not related to maltreatment referral; only parental factors were independent predictors.

CONCLUSIONS

Childhood neglect is associated significantly with delayed cognitive development and head growth. Addressing risk factors antenatally and in early childhood may improve outcomes.

A parent-completed developmental questionnaire: follow up of ex-premature infants

OBJECTIVE

Premature infants are at increased risk of developmental disability. Early identification of problems allows intervention to ameliorate or attenuate problems. A reliable screening tool allows triage of children in this high-risk population by identifying those unlikely to need full developmental assessment. To explore the test characteristics of an established parent-completed developmental assessment questionnaire 'Ages and Stages Questionnaire' (ASQ) in follow up of an Australian population of premature infants.

METHODOLOGY

One hundred and sixty-seven children born prematurely with corrected ages 12- to 48-months attending the Growth and Development Clinic at the Mater Children's Hospital in Brisbane, Queensland, Australia; 136 questionnaires 'ASQ' were returned completed (81%) and were compared to formal psychometric assessment (Griffith Mental Development Scales for 12- and 24-months, Bayley Mental Development Intelligence Scale for 18-months, McCarthy General Cognitive Intelligence Scale for 48-months). Developmental delay was considered to be present if any of the above psychometric assessments fell below 1.0 standard deviations (SD). The ASQ cut-off used was 2.0 SD (US data derived means and SD).

RESULTS

Aggregate results for all age groups comparing ASQ to psychometric assessments as 'gold standards' found the ASQ to have the following test characteristics: sensitivity (90%); specificity (77%); positive predictive value (40%); negative predictive value (98%); % over-referred (20%); % under-referred (1%); % agreement (79%). Likelihood ratio for children failing the ASQ was 3.8 and for passing the ASQ was 0.13. Twenty-one children with known disabilities were included in the study and in 14 of these, the ASQ overall score agreed with the psychometric assessment (67%).

CONCLUSION

The high negative predictive value of the ASQ supports its use as a screening tool for cognitive and motor delays in the follow up of ex-premature infants. This would need to be combined with other strategies as part of a comprehensive follow up program for ex-premature infants.

Gender differences in cognitive abilities at 2 years in ELBW infants. Extremely low birth weight

Gender differences in cognitive abilities exist for children born at term. For very preterm infants uncertainty exists regarding the presence and extent of such differences and their relationship to perinatal brain injury and neurological impairment. This study examined gender differences in cognitive abilities in a cohort of 336 extremely low birth weight (ELBW) infants at 2 years corrected age. Infants were classified as at low or high perinatal risk at birth according to four perinatal risk factors. A subgroup of 33 neurologically impaired infants was identified. Outcome at 2 years was measured by the overall General Quotient (GQ) on the Griffiths scale and its five subscale scores. Female ELBW children were superior to male ELBW children by 4.1 GQ points (95% CI 1.0, 7.1). If the impaired subgroup was excluded, the difference in GQ was 3.2 points (95% CI 0.4, 5.6), and this difference was predominantly due to female infants being superior in the hearing and speech subscale (6.0 points, 95% CI 2.6, 9.5). These differences were relatively independent of perinatal risk status. Gender differences in the Griffiths GQ for ELBW infants are similar to expected differences for term infants and are unlikely to cause substantial bias in interpreting outcome studies for ELBW infants, unless these involve tests of specific cognitive abilities such as language.

Postnatal depression-myth and reality: maternal depression before and after the birth of a child

BACKGROUND

Much has been written about postnatal depression as a clinical condition. There is some evidence to suggest that a substantial proportion of women who give birth experience a depression in the postnatal period. This paper reports the results of a longitudinal study of the mental health of a large sample of women who were in the early stages of pregnancy at entry to the study.

METHODS

Each participant was assessed for symptoms of depression at the first clinic visit (entry to the study), and reassessed at various intervals--at 3-5 days, at 6 months, and again at 5 years after the birth of the child--using the DSSI-D (Delusions-Symptoms-States Inventory).

RESULTS

Retrospective recall questions indicate that shortly after the birth the majority of women experienced some depressed mood. Of those who experienced depressed mood, the data suggest that the symptoms were not severe, nor did these symptoms generally continue beyond a few weeks. The longitudinal data indicate that levels of depression in our sample are highest either at the first clinic visit or at the 5-year follow-up. Rates of depression at the 6-month follow-up are relatively low by comparison.

CONCLUSION

While most mothers experience periods of depressed mood after the birth of their baby, these periods are generally of short duration and of lesser intensity than a major depression. Mothers appear to experience increasing levels of symptoms of depression as their child grows up. Many of the "cases" of depression experienced at the 5-year follow-up represent a recurrence of a previous experience of depression.

Behavioural and cognitive associations of short stature at 5 years

OBJECTIVES

To determine the extent to which childhood short stature is associated with cognitive, behavioural and chronic health problems, and whether these problems could be attributed to recognized adverse biological, psychosocial or psychological factors.

METHODOLOGY

At their first antenatal session, 8556 women were enrolled in a prospective study of pregnancy. When their children were 4 and 6 years of age, mothers completed a detailed questionnaire concerning their child's health and behaviour. A Peabody Picture Vocabulary Test-Revised (PPVT-R) was completed by the child at 5 years of age. Z scores were used to categorize height measurements in 3986 children. The relationship of these height categories with the child's health, and behavioural and cognitive problems was then examined.

RESULTS

No association was found between height and symptoms of chronic disease or behaviour problems in boys or girls. On the unadjusted analysis, mean PPVT-R scores were significantly lower in boys with heights < 3 percentile and 3-< 10 percentile compared with study children between 10 to 90 percentile (P < 0.01). Scores were similarly significantly lower in girls with heights < 3 percentile and 3-10 percentile (P = 0.01). Even after adjusting for psychosocial and biological confounders, short stature remained a significant predictor for lower PPVT-R scores in both boys and girls, although height only accounted for 1.1% of the variance in scores in boys and 0.5% of the variance in PPVT-R scores in girls. Psychosocial factors had a greater role than height in determining PPVT-R scores at 5 years of age.

CONCLUSIONS

These findings suggest a significant, though small, association between height and PPVT-R scores at 5 years of age, independent of psychosocial disadvantage and known biological risk factors.

Low alcohol preference among the "high alcohol preference" C57 strain of mice; preference increased by saline injections

RATIONALE AND OBJECTIVE

This study investigated individual alcohol preference among the "high alcohol preferring" strain of C57BL10 (line ScSn) mice.

METHODS

Alcohol preference was assessed in free choice two-bottle preference tests, using 8% ethanol and tap water, under various conditions.

RESULTS

Between 15 and 40% of the mice, bred in house, showed a low preference for alcohol with ethanol/water ratios of 0.4 or less. There was a biphasic distribution of preference, and no relationship between alcohol preference and gender. Mice of the C57BL/6 strain from an outside breeder also contained animals with low preference for alcohol. Selective breeding from "in house" stock did not demonstrate evidence of a simple genetic link. Ethanol preference showed no correlation with locomotor activity or the effects of alcohol on such activity. Daily intraperitoneal injections of saline increased the preference of low preference mice, an effect prevented by the CCK(B) antagonist, CAM1028. The preference of "low preference" mice was significantly increased when the effects of saline injections were compared with those of handling alone. Diazepam, at 1 mg/kg, did not affect the low preference, compared with Tween vehicle. This demonstration of C57 strain mice with low preference for alcohol may provide a valuable model for the effects of stress on alcohol consumption.

Executive function of children with extremely low birthweight: a case control study

This study examines the executive function (EF) skills of extremely-low-birthweight (ELBW) children at school compared with their peers. Thirty children with ELBW and 50 control children (both with a mean age of 62+/-4 months) were administered tests of EF including the Tower of Hanoi task, Finger Sequencing task, and Tapping Test. Children with ELBW, including those who scored more than 1 SD below the mean on the Peabody Picture Vocabulary Test-Revised, scored significantly lower than their peers on all executive tasks. There was limited correlation between EF and previous general quotient index scores obtained at routine assessment using the McCarthy Scales of General Ability at 4 years of age for the children with ELBW. Results suggest that children with ELBW are at risk for deficits in 'executive' behaviours including planning, sequencing, and inhibition which may have implications for later learning.

Aetiological factors and development in subjects with obstructive sleep apnoea

OBJECTIVE

To examine whether maternal pregnancy complications, adverse birth events, respiratory illnesses, or developmental difficulty were increased in neurologically normal children with obstructive sleep apnoea (OSA) and whether severity of OSA adversely affects the child's development and temperament.

METHODOLOGY

Maternal report of perinatal events, respiratory illness and developmental difficulty in 37 children with OSA was contrasted with a comparison group (n = 67). Children with OSA were assessed developmentally (Griffiths Scales), had a parental rating of temperament (Australian Temperament Scale) and attended an overnight polysomnographic sleep study.

RESULTS

Children with OSA had an increased prevalence of adverse maternal pregnancy and perinatal events, respiratory disease and developmental concerns. Limited associations were found between the severity of OSA and development or temperament difficulty.

CONCLUSIONS

This study suggests a relationship between OSA, though not its severity, and pre/perinatal adversity and child development. Polysomnographic and detailed developmental assessment of community-based samples of children with OSA and control children are necessary to confirm these findings.

Six-month follow-up of children with obstructive sleep apnoea

OBJECTIVES

This study examined prospectively changes in development, temperament and sleep related behaviour in children referred for obstructive sleep apnoea (OSA) and polysomnographic sleep study, some of whom had surgical intervention.

METHODOLOGY

Using a prospective cohort study design, parents of 56 children referred for OSA completed sleep and temperament questionnaires and their child was assessed developmentally at the time of the polysomnographic sleep study. Forty (72%) of the children were neurologically normal. At 6 months, 42 children were reassessed using sleep and temperament questionnaires and a developmental assessment. After excluding the primary snorers, subjects were categorised as having had intervention (n = 24) or not (n = 15), and differences over the 6-month period in Griffiths scores, temperament and sleep related behaviour were examined.

RESULTS

Regardless of intervention status, there was an improvement in night-time and day-time sleep behaviour for the total group, though the extent of improvement was more marked in the intervention group. For the neurologically normal children, improvement in the sleep behaviour was only significant for the intervention group (P < 0.05). Intervention did not result in any significant changes in Griffiths developmental score or temperament.

CONCLUSION

Surgical intervention improves sleep behaviour in children though not temperament or development.

The influence of growth on development outcome in extremely low birthweight infants at 2 years of age

OBJECTIVE

To determine if weight < 3rd and < 10th centile at 2 years in extremely low birthweight (ELBW) infants is associated with problems of development and motor skills, and whether this association is explained by perinatal risk status.

METHODOLOGY

One hundred and ninety-eight of 226 (88%) surviving ELBW infants born between January 1987 and December 1992 were assessed at 2 years corrected age. Children were classified as being at low perinatal risk (n = 128) or high perinatal risk (n = 70) for adverse developmental outcome based on perinatal risk factors. Weight at 2 years was classified as < 3rd, 3rd-9th or > or = 10th centile for age and gender. Development was assessed using the Griffiths Mental Developmental Scales and motor skills using the Neurosensory Motor Developmental Assessment (NSMDA).

RESULTS

For the total study group weight centile was strongly related to General Quotient (GQ) and motor abilities. For children < 3rd percentile (n = 48) mean (GQ) was 90.4 (SD, 15.9), for children between the 3rd-9th percentile (n = 49) 91.5 (SD, 17.9), and for children > or = 10th percentile (n = 99) mean GQ was 99.8 (SD, 8.6). The association with mean GQ and NSMDA category occurred for the high-risk subgroup and became non-significant in the low-risk subgroup if neurologically abnormal children were excluded. Other perinatal risk factors, exposure to breast milk, level of maternal education, marital status and history of feeding problems or infections over the 2 years did not confound this association.

CONCLUSION

Low weight percentile at 2 years was related to adverse developmental outcome in ELBW infants at high perinatal risk or with neurological impairment, though minimal association was present for neurologically normal infants at low perinatal risk.

Clinical versus polysomnographic profiles in children with obstructive sleep apnoea

OBJECTIVE

To examine the clinical and polysomnographic (PSG) profiles of neurologically normal and abnormal children with obstructive sleep apnoea (OSA) and explore the relationship between these profiles.

METHODOLOGY

We enrolled 56 children with persistent snoring and OSA for the study, 16 of whom were neurologically abnormal. All children were examined clinically and attended an overnight PSG study. Total clinical scores, PSG scores, and mild/moderate or severe ratings were derived for each child.

RESULTS

Comparison of individual PSG parameters with neurological status demonstrated that the abnormal children had significantly increased obstructive apnoea indices, increased desaturation events and lower mean arousal indices compared to their neurologically normal OSA peers. For the neurologically abnormal children, there was a significant correlation between severity ratings of disease according to clinical and PSG profiles (r = 0.56, P = 0.03, sensitivity 82%) using the clinical summary as the gold standard, although the association was less marked in the neurologically normal children (r = -0.08, P = NS, sensitivity 69%).

CONCLUSION

Neurologically abnormal children are likely to have more severe abnormalities in selected polysomnographic indices and overall scores. However, the clinical assessment is only likely to reflect this at the severe end of the spectrum. These relationships are not seen in the neurologically normal child, where little or no reliance can be placed upon predicting the severity of the polysomnographic findings from the clinical data. Decisions regarding the severity of disease and treatment should be based on the combined findings of the clinical and PSG data rather than overall clinical and polysomnographic scores or selected clinical and polysomnographic parameters.

Placental pathology and neurodevelopment of the infant with intrauterine growth restriction

The placentas of 68 infants with intrauterine growth restriction (IUGR) were examined for evidence of impaired uteroplacental circulation and compared with those of 65 appropriately grown infants. Infarcts and/or accelerated villous maturation were present in the placentas in 27 (40%) of the infants with IUGR compared with seven (11%) of the infants without IUGR (P<0.001). The infants were followed-up at 4 and 12 months of age and growth parameters recorded. Medical and developmental assessments and neuromotor developmental examinations were also performed. The 23 infants in the IUGR group with placentas with evidence of impaired uteroplacental circulation were compared with the 31 infants with IUGR with normal placentas. There was no difference between the groups in growth, cognitive development, or neuromotor abnormality. It was concluded that IUGR is strongly associated with placental markers of impaired uteroplacental blood flow while it would appear that there is no association between placental pathology and growth or neurodevelopment in the first year.

Maternal hypertension and neurodevelopmental outcome in very preterm infants

AIM

To determine the outcome of preterm infants born to mothers with hypertension during pregnancy, and preterm controls.

METHODS

107 infants of 24-32 weeks gestation, born to hypertensive mothers, and 107 controls matched for gestational age, sex, and multiple pregnancy, born to normotensive mothers, were prospectively enrolled over 2 years. Information on maternal complications and medication was obtained and neonatal mortality and morbidities recorded. Survivors were followed up to at least 2 years, corrected for prematurity.

RESULTS

One third of the hypertensive mothers were treated with antihypertensive drugs, while 18% received convulsion prophylaxis with phenytoin. Magnesium sulphate was not prescribed. Both groups had a mean gestational age of 29.9 weeks, with the study infants having a significantly lower birthweight than the controls. Four study and three control infants died in the neonatal period. Cerebral palsy was not diagnosed in any infant of a hypertensive mother compared with five of the controls. The mean general quotient for the two groups was very similar and no difference in the incidence of minor neuromotor developmental problems was shown.

CONCLUSIONS

Maternal hypertension seems to protect against cerebral palsy in preterm infants without increasing the risk of cognitive impairment. This was independent of the use of maternally administered magnesium sulphate.

Obstetric and perinatal factors as predictors of child behaviour at 5 years

OBJECTIVE

To identify whether obstetric and perinatal factors are independent predictors of child behaviour at 5 years.

METHODOLOGY

The Mater University Study of Pregnancy (MUSP) is a prospective cohort study of 8556 mothers enrolled in early pregnancy. The relationship of obstetric and perinatal factors, maternal lifestyle, age and gender of the child, and social disadvantage were examined as predictors of child behaviour in 5005 children completing a modified child behaviour checklist at 5 years. This checklist contained three independent groups of behaviour: externalizng, internalizing and SAT (social, attentional and thought problems).

RESULTS

In the initial analysis a limited number of associations were present. After adjusting for measures of social disadvantage, only number of antenatal admissions was associated with child behaviour in all three scales, while maternal cigarette smoking in pregnancy and male gender were associated with externalising and SAT behaviours.

CONCLUSIONS

Most common epidemiologic obstetric and perinatal risk factors were not independent predictors of behaviour problems in children at 5 years.

Biological predictors and co-morbidity of attention deficit and hyperactivity disorder in extremely low birthweight infants at school

OBJECTIVE

To examine biological predictors and co-morbidity of Attention Deficit Hyperactivity Disorder (ADHD) and associated academic and social impairment in a cohort of extremely low birthweight of (ELBW) children attending school.

METHODOLOGY

Eight seven (70%) of 125 ELBW children born between 1977 and 1986 were followed prospectively. Neonatal and biological data including cranial ultrasound for 62% of children, formal developmental assessment at 4 or 6 years of age, teacher and parent ADHD questionnaire, parental rating of health status and social impairment and school teacher rating of academic performance was recorded.

RESULTS

Apart from grades 3 or 4 intraventricular haemorrhage in a minority of children, there was no evidence to suggest an association between ADHD and perinatal adversity in ELBW children. Social impairment, academic difficulty and atopic symptoms were significantly related to ADHD.

CONCLUSIONS

Extremely low birthweight children presenting with symptoms of ADHD are likely to suffer social and learning impairment and these, rather than perinatal risk factors, should be the focus of clinical attention.

Characteristics at four months follow-up of infants born small for gestational age: a controlled study

This prospective study compared 65 small-for-gestational-age (SGA) (birth weight < 3rd centile) and 71 control infants at a corrected age of 4 months. It was hypothesised that differences would exist in growth, development, temperament and minor neurological signs and that these would be predicted by type (proportional/disproportional) of growth restriction at birth and maternal mood disturbance at birth or at 4 months. Infants had a Griffith's developmental test and neuromotor assessment. Maternal mood and infant temperament were surveyed. Few differences were found between SGA and control infants. SGA infants showed catch-up growth with 63% being above the third percentile and 43% being above the tenth percentile for weight. SGA infants had lower Griffith's GQ scores (97 vs. 102, P = 0.02) and they were rated in temperament as more manageable than controls. There were no differences in subtle neuromotor signs. Neither type of SGA nor maternal mood disturbance at birth had prognostic significance for infant catch up growth, neuromotor scores, or temperament though level of maternal stress and anxiety at 4 months were related to lower GQ scores in SGA infants.

Prediction of obesity in children at 5 years: a cohort study

OBJECTIVE

To examine determinants of moderate and severe obesity in children at 5 years of age.

METHODOLOGY

A prospective cohort of mothers were enrolled at first antenatal visit, and interviewed shortly after delivery, at 6 months and 5 years. Detailed health, psychological and social questionnaires were completed at each phase by mothers, and child health questionnaires at 6 months and 5 years. At 5 years 4062 children were assessed physically, the Peabody Picture Vocabulary Test administered and mothers completed a modified Child Behaviour Checklist. Moderate obesity was defined as BMI between 85th and 94th percentiles inclusively, and severe obesity as a BMI greater than the 94th percentile.

RESULTS

Independent predictors of severe obesity at 5 years were birthweight, female gender, maternal BMI and paternal BMI. Moderate obesity at 5 years was predicted by birthweight, paternal BMI and sleeplessness at 6 months, while small for gestational age (SGA) status and feeding problems at 6 months were protective factors for moderate obesity. Obesity was not associated with problems of language comprehension or behaviour.

CONCLUSIONS

Findings of this study suggest that biological rather than psychosocial factors are the major determinants of obesity at 5 years.

Aetiology and classification of small for gestational age infants

OBJECTIVE

To determine important aetiological factors in small gestational age (SGA) infants and the effectiveness of anthropometric indexes in identifying patterns of growth retardation.

METHODOLOGY

Eighty-four SGA infants and 81 controls were enrolled. Maternal biological, lifestyle and psychosocial factors were compared for the total group and the term Caucasian subset. Anthropometric indexes were also examined in relation to growth patterns.

RESULTS

Decreased maternal size, poor weight gain, previous SGA infant and smoking were significantly associated with SGA status. Poor parental education and unemployment was increased in the study group. Mothers of SGA infants, especially the term Caucasian group, had a greater prevalence of hypertension and depressive and stress symptomatology. Ponderal index failed to identify discreet patterns of disproportionate/proportionate growth retardation.

CONCLUSION

Biological, lifestyle and psychosocial differences remain important aetiological factors of intrauterine growth retardation. Identification of specific patterns of growth retardation by ponderal index remains controversial.

Survival and neonatal and neurodevelopmental outcome of 24-29 week gestation infants according to primary cause of preterm delivery

A total of 189 infants of 24-29 weeks' gestation were born in a regional perinatal centre during a 2-year period. They were divided into groups according to the primary cause of preterm delivery: antepartum haemorrhage (n = 37, 20%), preeclampsia (n = 27), 14%), preterm premature rupture of membranes (n = 64, 34%), preterm labour (n = 27, 14%), chorioamnionitis (n = 16, 8%), other complications (n = 18, 10%). The perinatal mortality rate (PMR) was 286/1,000 of whom 44% were stillbirths. The 'other complication' group had the highest PMR due to a large number of intrauterine deaths, with no differences in neonatal mortality between the groups. Preeclampsia was associated with an increased risk of necrotizing enterocolitis and chorioamnionitis was associated with an increased risk of periventricular haemorrhage. Follow-up to at least 2 years was performed in 122 (97%) of survivors. Cerebral palsy occurred in 7%, while 18% had neurodevelopmental disability. No relationship was found between primary cause of preterm delivery and outcome. This information should be of value in counselling parents when preterm delivery is imminent.

Prevalence of maternal depression and its relationship to ADL skills in children with developmental delay

OBJECTIVE

To determine the prevalence of maternal affective symptoms in children with developmental problems compared to a control group, and to examine their relationship to the child's Activities of Daily Living (ADL), socialization skills and behaviour.

METHODOLOGY

This study examined prospectively the prevalence of symptoms of maternal depression, maternal anxiety, stress and adverse life events in 65 mothers whose children were attending a Child Development Clinic. ADL and socialization skills were measured using the Vinelands Adaptive Behaviour Scales, and behaviour using a checklist.

RESULTS

Symptoms of maternal depression (P = 0.04), maternal anxiety (P = 0.01) and number of adverse life events (P = 0.03) were increased in the study compared to control mothers. Presence of maternal symptoms was unrelated to ADL or socialization skills though was associated with increased behavioural symptoms in the child.

CONCLUSION

Affective disturbance in mothers of children with developmental problems are common and should be addressed as part of a comprehensive assessment of such children.

School performance of ELBW children: a controlled study

This paper examines the prevalence of learning difficulty in reading, spelling, mathematics and writing and the prevalence of attention deficit disorder (ADD) in extremely low-birthweight (ELBW) children at school compared to their peers. Parents of 87 eligible ELBW children completed an educational questionnaire and questionnaire for ADD. Teachers of the ELBW children completed a detailed educational and ADD questionnaire for the study child and two control children in the same class, matched for age and nearest in birth date to the study child. Parents reported that 4% of the ELBW children born between 1977 and 1986 were in a special education unit, 46% received remedial help and 21% repeated a grade. Teacher assessment of six aspects of reading and spelling and five aspects of mathematics and writing skills indicated that the ELBW children experienced marked problems in all areas compared to control children and were approximately 3 times more likely to be delayed by more than a year in all areas. Prevalence of ADD was not increased in the ELBW children compared to the control group, though males in both groups had a higher prevalence of symptoms. Early intervention and special education resources must be available for ELBW children attending school.

Prevalence and aetiology of neurological impairment in extremely low birthweight infants

OBJECTIVE

To determine the prevalence and perinatal predictors of cerebral palsy, intellectual impairment, visual impairment and deafness in a cohort of extremely low birthweight (ELBW) infants at two years of age.

METHODOLOGY

The study population comprised 199 of the 224 (89%) ELBW infants managed at the Mater's Mothers Hospital, Brisbane, between July 1977 and February 1990 and who survived to two years. The prevalence of cerebral palsy, intellectual impairment, blindness and deafness was measured by clinical,psychometric and audiological assessment and the association with 24 risk factors examined.

RESULTS

Cerebral palsy occurred in 20 children (10%). Risk of cerebral palsy was associated with ventricular dilatation, intraventricular haemorrhage, necrotizing enterocolitis and multiple birth, though only ventricular dilatation (OR 4.41; 95% CI 1.32-14.8) remained significant in the adjusted analysis. Intellectual impairment occurred in 20 children (10%) and was independently associated with ventricular dilatation (OR 15.0; 95% CI 2.2-102.8), ventilation F(i)(2) > 80% (OR 3.4; 95% CI 1.01-11.5), vaginal delivery (OR 3.5; 95% Cl 1.09-11.4) and male sex (OR 6.1; 95% Cl 1.67-22.3). No perinatal predictor was statistically associated with risk of deafness. Retinopathy of prematurity (OR 36.9; 95% Cl 2.8-495.5) was associated with risk of later visual impairment.

CONCLUSIONS

Intellectual impairment was associated with a broad range of perinatal variables. Cerebral palsy was associated with fewer variables, all of which were also associated with intellectual impairment. Neurologic injury was associated with male sex and multiple birth, which are not biological insults themselves, but may be markers of susceptibility to injury.

Neurodevelopmental outcome of preterm infants with bronchopulmonary dysplasia

The neurodevelopmental outcome of 78 infants with bronchopulmonary dysplasia (BPD) was compared with that of 78 control infants matched for birthweight. To determine the effect of the severity of BPD, 62 infants requiring oxygen at 36 weeks' postmenstrual age (sBPD) were compared with their matched controls. Infants were followed up to 2 years of age, corrected for prematurity, and were classified for neurological impairment, developmental delay, and neurodevelopmental disability. Seventy six (98%) BPD infants and 71 (91%) controls had follow up data available to two years. Neurological impairment, developmental delay, and neurodevelopmental disability occurred more frequently in infants with BPD than in controls but this was not significant. For infants with sBPD, the increased incidence of neurological impairment and definite developmental delay was not significant when compared with the controls, though neurodevelopmental disability occurred more frequently (odds ratio (OR) 3.6: 95% confidence intervals (CI) 1.1-11.8). Predictors of disability in infants with sBPD included periventricular haemorrhage (OR 19.4: 95% CI 4.3-86.6), ventricular dilatation (OR 12.8: 95% CI 2.9-57.3), and sepsis (OR 5.0: 95% CI 1.3-19.4). Adjusting for the presence of these factors, the association between BPD and disability was no longer apparent (OR 0.9: 95% CI 0.2-3.6). The findings suggest that BPD is not independently associated with adverse neurodevelopmental outcome.

Changing patterns of survival and outcome at 4 years of children who weighted 500-999 g at birth

OBJECTIVE

To evaluate the impact of changing perinatal practices on survival rates and 4 year neurodevelopmental outcome for infants of birthweight 500-999 g.

METHODOLOGY

The study was a tertiary hospital-based prospective cohort study that compared survival, impairment and handicap rates between two eras, July 1977 to December 1982 (era 1) and January 1983 to June 1988 (era 2). All 348 live, inborn infants and 49 outborn infants of birthweight 500-999 g were prospectively enrolled in a study of survival and outcome. Rates of survival, neurodevelopmental impairment and functional handicap at 4 years were compared between eras. Perinatal risk factors for handicap were also compared between eras.

RESULTS

Four year survival rates for inborn infants 500-999 g improved from 32.6% in era 1 to 49.2% in era 2 (OR 2.1, 95% CI 1.26-3.48) but for outborn infants the improvement between 31.8% and 53.6% was not significant. There were significant improvements in survival for inborn infants in birthweights 800-899 g and 900-999 g between study periods. The rates of functional handicap between the first and second eras (mild 10 vs 7%; severe or multiply severe 14 vs 16%) were not significantly different. Although the rate of cerebral palsy increased from 0 to 12% (P < 0.01) other rates of impairment such as blindness 0 vs 3%, deafness 2 vs 2% and developmental delay 12 vs 11% did not change. The chance of a survivor being free of handicap remained unchanged at 78% and 76% for the two eras, respectively. Although the absolute number of intact survivors more than doubled (41 vs 83) so too did the number of severe or multiply severe handicapped survivors (7 vs 17). Multivariate logistic regression analysis for the entire study cohort revealed male gender, multiple birth, prolonged mechanical ventilation and cerebral ventricular dilatation but not birthweight or gestational age to be independently associated with severe or multiply severe handicap.

CONCLUSIONS

The advances in neonatal intensive care for extremely low birthweight infants between July 1977 and December 1982 and January 1983-June 1988 resulted in an increased number of non-disabled survivors but had no impact on incidence of severe disability. The application of prediction of mortality or severe handicap to clinical practice has the potential to reduce the proportion and absolute number of severely handicapped survivors.

Improvement of spatial light modulator optical input/output performance using microlens arrays

Advanced spatial light modulators both detect incident light and modulate reflected light. Each pixel may contain multiple photodetectors, a modulator, control circuitry, and signal-processing circuitry. Because each detector and modulator occupies only a fraction of the area of a pixel the optical efficiency of these devices suffers. We have experimented with improving optical input/output performance by integrating a microlens array with a ferroelectric liquid-crystal VLSI spatial light modulator. We have studied the microlens VLSI spacing accuracy that must be achieved to yield minimum distortion of ref lected wave fronts and the best optical efficiency for Fourier-transform applications.

Extremely low birth weight and control infants at 2 years corrected age: a comparison of intellectual abilities, motor performance, growth and health

A 2-year cohort of 63 surviving extremely low birth weight (ELBW) infants was prospectively studied and 60 of these infants, together with 44 normal birth weight control infants, were assessed at 2 years of age for intellectual abilities, motor skills, growth and health. The total ELBW group differed significantly from controls on overall Griffiths developmental quotient (99.3 vs. 103.8 P = 0.02) and in the personal/social subscale (100.7 vs. 106.7 P = 0.01). A subset of 43 of the ELBW infants was identified as low risk at discharge. No statistically significant differences were present between the low risk ELBW subset and controls in intellectual abilities though both the total ELBW group and the low risk ELBW subset differed from controls in fine and gross motor abilities, and in weight at 2 years. The total ELBW group also experienced more frequent ill health and hospital readmission.

Prognostic factors and long-term outcomes for children who have nearly drowned

OBJECTIVE

To find predictors of outcome and to describe the long term outcome for children who require mechanical ventilation after nearly drowning.

PATIENTS AND SETTING

From 1981 to 1989, all children who underwent ventilation in the Intensive Care Unit of the Master Children's Hospital, Brisbane, after an immersion. Children who died within 24 hours were excluded. Of 57 children eligible for entry, 18 died after 24 hours.

DESIGN

Retrospective study of hospital records and prospective assessment of neurodevelopmental outcome. Thirty-eight families of survivors were contacted by questionnaire and 25 children of these families were examined. Follow-up was between 0.8 and 9.6 years after immersion.

RESULTS

All children who had a motor response to pain in the hospital's emergency department survived without sequelae. Thirty-one children were in cardiac arrest and, of these, 17 died, six survived with severe spastic quadriplegia and eight are ambulant. Of those ambulant, four have motor coordination difficulties and three have learning difficulties. Children in cardiac arrest who had a delay of more than 20 minutes between rescue and arrival at hospital were more likely to die or sustain severe spastic quadriplegia. No child survived if more than 25 minutes of advanced resuscitation was required after they had been warmed.

CONCLUSIONS

Children with a motor response to pain seem to have a good prognosis. However, we could not predict which children in cardiac arrest would die or survive either severely impaired or ambulant. All children in cardiac arrest should receive aggressive resuscitation for at least 25 minutes after being warmed; they have a better prognosis if advanced resuscitation is started less than 20 minutes after rescue. Children who survive a cardiac arrest without spastic quadriplegia warrant long term surveillance as they may have coordination and learning difficulties.

Handedness in extremely low birth weight infants: aetiology and relationship to intellectual abilities, motor performance and behaviour at four and six years

Hand preference was measured in a total group of 71 ELBW children to determine patterns of hand preference at 4 and 6 years, possible aetiological factors leading to handedness, and whether left or non right hand preference were markers for intellectual, motor, temperament or behavioural differences. At both 4 and 6 years the prevalence of left handedness was increased, though this prevalence changed over the period of the study. Results supported brain injury as one mechanism leading to increased left hand preference, though this process did not adequately explain this increase. Possible reasons for this and the apparent change in prevalence with time are examined. Mixed handedness at 4 years was associated with lower intellectual abilities though otherwise children were similar in motor skills, temperament and behaviour independent of hand preference category.

The prevalence and origins of left hand preference in high risk infants, and its implications for intellectual, motor and behavioural performance at four and six years

This study investigates the origins of hand preference at 4 years in a cohort of 115 high risk and premature infants; the relationship between patterns of hand preference and intellectual, motor, temperament and behavioural status at 4 and 6 years; and evidence for brain injury in mediating the relationship between hand preference and development disorder. Increased left hand preference was independently associated with extreme prematurity, high neonatal risk, increased numbers of minor physical anomalies, lowered intellectual and motor abilities, and more difficult temperament. These findings supported the presence of intrauterine and neonatal pathological mechanisms leading to left hand preference in a small number of children. Neither poor function of the non dominant hand nor absence of a family history of left handedness could further define this pathological subgroup. Support for pathological mechanisms producing left handedness was found predominatly in the infants of high birth weight, whereas prevalence of left handedness was increased mainly among the extremely low birth weight infants. In this latter group the prevalence of left handedness was also increased among children of normal intelligence, suggesting that mechanisms other than brain damage lead to left hand preference in very premature infants.

Perinatal hypoxic-ischaemic brain injury: prediction of outcome

Twenty-six term babies with hypoxic-ischaemic brain injury were studied during the neonatal period to evaluate the prediction of outcome to at least one year of age by means of ultrasonography, CT scanning and Doppler ultrasound assessment of cerebral palsy blood flow velocity (CBFV). Adverse outcome was defined as the occurrence of cerebral palsy, developmental delay or death. At follow-up, 17 infants had an adverse outcome (seven died, 10 had disability); the remainder had no detectable impairment. Abnormalities on cranial ultrasound were not, but generalised decreased tissue density on CT scan was, associated with adverse outcome. Abnormal mean CBFV in the middle cerebral artery had no association with outcome, but abnormal mean CBFV in the anterior cerebral artery and a low resistance index in both arteries were significantly associated with adverse outcome. Such information may be used for appropriate counselling of parents of asphyxiated infants.

Single daily dose ceftriaxone therapy in epiglottitis

Ceftriaxone as a single daily intravenous dose for 5 days was used to treat seven patients with proven Haemophilus influenzae epiglottitis. All children responded favourably. The serum levels achieved exceeded the MIC by up to 1500 times at the trough level during and for up to 24 h after the completion of the treatment. Side effects were mild and transient and did not disrupt the continuity of the treatment. Ceftriaxone potentially offers a number of clinical and economic advantages in the management of epiglottitis.

Diffractive ferroelectric liquid-crystal shutters for unpolarized light

Electro-optic modulators using ferroelectric liquid-crystal technology have generally been limited to use with polarized light. It is possible, however, to construct a diffractive array of ferroelectric liquid-crystal phase modulators that can act as a shutter for unpolarized light. We have built two types of polarization-independent diffractive shutter based on this principle. We describe their principles of operation and performance.