Extremely low-birth-weight infants less than 901 g: development and behaviour after 4 years of life

Body Structure, Function, Activity, and Participation in 3- to 6-Year-Old Children Born Very Preterm: An ICF-Based Systematic Review and Meta-Analysis

BACKGROUND

The World Health Organization's International Classification of Functioning, Disability, and Health framework, Children and Youth Version (ICF-CY), provides a valuable method of conceptualizing the multidomain difficulties experienced by children born very preterm (VP). Reviews investigating motor outcomes at preschool age across ICF-CY domains are lacking.

PURPOSE

The purpose of this review is to identify and compare motor outcomes of 3- to 6-year-old children born VP and children born full-term (FT) within the ICF-CY framework.

DATA SOURCES

Four electronic databases and reference lists of included and key articles were searched.

STUDY SELECTION

Studies comparing motor outcomes of 3- to 6-year-old children born VP (<32 weeks' gestation or birth weight <1500 g) with peers born FT were included.

DATA EXTRACTION

Two independent authors extracted data and completed quality assessments.

DATA SYNTHESIS

Thirty-six studies were included. Activity motor performance of children born VP was consistently poorer compared with peers born FT: standardized mean difference (SMD) was -0.71 (95% CI = -0.80 to -0.61; 14 studies, 2056 participants). Furthermore, children born VP had higher relative risk (RR) of motor impairment (RR = 3.39; 95% CI = 2.68 to 4.27; 9 studies, 3466 participants). Body structure and function outcomes were largely unable to be pooled because assessment tools varied too widely. However, children born VP had higher RR of any neurological dysfunction (Touwen Neurological Examination) (RR = 4.55; 95% CI = 1.20 to 17.17; 3 studies, 1363 participants). There were no participation outcome data.

LIMITATIONS

Limitations include the lack of consistent assessment tools used in VP follow-up at preschool age and the quality of the evidence.

CONCLUSIONS

Children born VP experience significant motor impairment across ICF-CY activity and body structure and function domains at preschool age compared with peers born FT. Evidence investigating participation in VP preschool-age populations relative to children born at term is sparse, requiring further research.

Attention-Deficit/Hyperactivity Disorder and Very Preterm/Very Low Birth Weight: A Meta-analysis

CONTEXT

Although very preterm (VP), extremely preterm (EP), very low birth weight (VLBW), and extremely low birth weight (ELBW) newborns seem to have a higher risk of later attention-deficit/hyperactivity disorder (ADHD), the magnitude of the risk is not well-defined.

OBJECTIVE

To systematically review and meta-analyze the risk of VP/VLBW and EP/ELBW individuals to develop a ADHD categorical diagnosis or dimensional symptomatology compared with controls with normal weight and/or birth age.

DATA SOURCES

We used PsycINFO, Medline, Embase, and Cochrane databases.

STUDY SELECTION

We selected cross-sectional, prospective, or retrospective studies with no time or language restriction.

DATA EXTRACTION

Independent reviewers screened and extracted data using predefined standard procedures.

RESULTS

In 12 studies (N = 1787), researchers relying on a categorical diagnosis showed that both VP/VLBW and EP/ELBW subjects have a higher ADHD risk (odds ratio [OR] = 3.04 higher than controls; 95% confidence interval [CI] 2.19 to 4.21). In subgroup analyses, we demonstrated that the more extreme the cases, the higher the ORs (VP/VLBW: OR = 2.25 [95% CI 1.56 to 3.26]; EP/ELBW: OR = 4.05 [95% CI 2.38 to 6.87]). We drew data from 29 studies (N = 3504) on ADHD symptomatology and found significant associations with inattention (standardized mean difference [SMD] = 1.31, 95% CI 0.66 to 1.96), hyperactivity and impulsivity (SMD = 0.74, 95% CI 0.35 to 1.13), and combined symptoms (SMD = 0.55, 95% CI 0.42 to 0.68) when compared with controls.

LIMITATIONS

Heterogeneity was significantly high for all analyses involving the 3 ADHD dimensions.

CONCLUSIONS

With our results, we provide evidence that VP/VLBW subjects have an increased risk of ADHD diagnosis and symptomatology compared with controls, and these findings are even stronger in the EP/ELBW group. Future researchers should address which risk factors related to prematurity or low birth weight lead to ADHD.

Neuropsychological Outcomes in Extremely Preterm Preschoolers Exposed to Tiered Low Oxygen Targets: An Observational Study

An observational study of neuropsychological outcomes at preschool age of tiered lowered oxygen (O2) saturation targets in extremely preterm neonates. We studied 111 three-year-olds born <28 weeks' gestational age. Fifty-nine participants born in 2009-2010 during a time-limited quality improvement initiative each received three-tiered stratification of oxygen rates (83-93% until age 32 weeks, 85-95% until age 35 weeks, and 95% after age 35 weeks), the TieredO2 group. Comparisons were made with 52 participants born in 2007-2008 when pre-initiative saturation targets were non-tiered at 89-100%, the Non-tieredO2 group. Neuropsychological domains included general intellectual, executive, attention, language, visuoperceptual, visual-motor, and fine and gross motor functioning. Descriptive and inferential analyses were conducted. Group comparisons were not statistically significant. Descriptively, the TieredO2 group had better general intellectual, executive function, visual-motor, and motor performance and the Non-tieredO2 group had better language performance. Cohen's d and confidence intervals around d were in similar direction and magnitude across measures. A large effect size was found for recall of digits-forward in participants born at 23 and 24 weeks' gestation, d=0.99 and 1.46, respectively. Better TieredO2 outcomes in all domains except language suggests that the tiered oxygen saturation target method is not harmful and merits further investigation through further studies. Benefit in auditory attention appeared greatest in those born at 23 and 24 weeks. Participants in the tiered oxygen saturation group also had fewer ventilation days and a lower incidence of bronchopulmonary dysplasia, perhaps explanatory for these neuropsychological outcomes at age 3.

Provider use of corrected age during health supervision visits for premature infants

INTRODUCTION

Correcting age for prematurity is recommended by the American Academy of Pediatrics and the Centers for Disease Control and Prevention. The use of chronological age instead of corrected age for infants born prematurely may result in incorrect interpretations regarding the adequacy of a child's growth or developmental progress and has the potential to negatively affect care. This study examined the frequency and impact of the use of corrected age by primary care providers.

METHOD

A retrospective cross-sectional electronic health record review was performed for all infants < 32 weeks' gestation who were seen for a health supervision visit in a 31-site pediatric network during a 1-year period. Primary care providers used an electronic health record that defaulted to chronological age information.

RESULTS

Primary care providers used corrected age for developmental surveillance for 24% of visits, they used chronological age for 71% of visits, and the age used was unclear in 5% of visits. The lower a child's gestational age and the more that chronological age was used, the more concerns were identified by primary care providers. Dietary changes that included the introduction of solid foods, the start of fluoride, and the introduction of milk typically were recommended on the basis of chronological age.

DISCUSSION

Primary care providers used chronological age more than corrected age, which influenced assessment and recommendations for care. This study illustrates the impact of not using corrected age, the importance of ensuring that care aligns with guidelines, and the possible influence of the design of the electronic health record on patient care. Because families of premature infants rely on primary care providers to accurately identify sequelae associated with prematurity, and to provide reassurance when it is warranted, these findings have implications for all health care providers who treat premature infants.

Perinatal events and motor performance of children born with ELBW and nondisabled

PURPOSE

To explore the relationship between perinatal variables and motor performance in children who were born with extremely low birth weight (ELBW) and were nondisabled at 1 and 4 years.

METHODS

Children without neurological or cognitive impairment (n = 48) born weighing less than 1000 g between 1992 and 1994 were assessed at 1 and 4 years corrected age using the Neurosensory Motor Developmental Assessment (NSMDA). Scores were used to categorize motor performance as normal or abnormal.

RESULTS

Chronic lung disease (CLD) of prematurity, necrotizing enterocolitis (NEC), and patent ductus arteriosus were associated with NSMDA category at 1 year. Chronic lung disease, male gender, and NEC were associated with NSMDA category at 4 years. Multiple regression analyses revealed that CLD and NEC were independently associated with abnormal motor outcomes at 1 year.

CONCLUSIONS

Early assessment and motor therapy is recommended for infants with CLD, because of its effect on motor performance in this otherwise healthy group of children born with ELBW.

Focused attention, heart rate deceleration, and cognitive development in preterm and full-term infants

The majority of children who are born very preterm escape major impairment, yet more subtle cognitive and attention problems are very common in this population. Previous research has linked infant focused attention during exploratory play to later cognition in children born full-term and preterm. Infant focused attention can be indexed by sustained decreases in heart rate (HR). However there are no preterm studies that have jointly examined infant behavioral attention and concurrent HR response during exploratory play in relation to developing cognition. We recruited preterm infants free from neonatal conditions associated with major adverse outcomes, and further excluded infants with developmental delay (Bayley Mental Development Index [MDI < 70]) at 8 months corrected age (CA). During infant exploratory play at 8 months CA, focused attention and concurrent HR response were compared in 83 preterm infants (born 23-32 weeks gestational age [GA]) who escaped major impairment to 46 full-term infants. Focused attention and HR response were then examined in relation to Bayley MDI, after adjusting for neonatal risk. MDI did not differ by group, yet full-term infants displayed higher global focused attention ratings. Among the extremely preterm infants born <29 weeks, fewer days on mechanical ventilation, mean longest focus, and greater HR deceleration during focused attention episodes, accounted for 49% of adjusted variance in predicting concurrent MDI. There were no significant associations for later-born gestational age (29-32 weeks) or full-term infants. Among extremely preterm infants who escape major impairment, our findings suggest unique relationships between focused attention, HR deceleration, and developing cognition.

The effect of extremely preterm birth on attachment organization in late adolescence

BACKGROUND

Prior studies have examined the impact of preterm birth on the quality of the attachment relationship to the mother in infancy, but few have examined extremely preterm born infants and almost no data have been reported on prematurity and its impact on the attachment organization attained after childhood.

METHODS

Thirty-nine adolescents born extremely preterm and 39 full-term born control participants were assessed with the Adult Attachment Interview.

RESULTS

The prematurely born showed lower scores regarding measures of attachment security and, in particular, a higher proportion of insecure dismissive patterns. This difference seemed to be clear and persistent even when controlled for intelligence and socio-economic variables.

CONCLUSIONS

Because insecure attachment as well as prematurity may be considered as significant risk factors for developing psychopathology, they deserve careful attention in future research and clinical follow-ups.

Regulation of corticoid and serotonin receptor brain system following early life exposure of glucocorticoids: long term implications for the neurobiology of mood

Potent glucocorticoids (GC) administered early in life have improved premature infant survival dramatically. However, these agents may increase the risk for physical, neurological and behavior alterations. Anxiety, depression and attention difficulties are commonly described in adolescent and young adult survivors of prematurity. In the present study we administered vehicle, dexamethasone, or hydrocortisone to Sprague-Dawley rat pups on postnatal days 5 and 6, mimicking a short term clinical protocol commonly used in human infants. Two systems that are implicated in the regulation of stress and behavior were assessed: the limbic-hypothalamic-pituitary-adrenal axis [LHPA; glucocorticoid and mineralocorticoid receptors within] and the Serotonin (5-HT) system. We found that as adults, male Sprague-Dawley pups treated with GC showed agent specific altered growth, anxiety-related behavior, changes in corticoid response to novelty and gene expression changes within LHPA and 5-HT-related circuitry. The data suggest that prolonged GC-receptor stimulation during the early neonatal period can contribute to the development of individual differences in stress response and anxiety-related behavior later in life.

Follow-up studies of very low birthweight children in Sweden

Follow-up studies are essential to our knowledge of outcome in very low birthweight (VLBW) or extremely preterm (EPT) infants because those children have a greater risk for developing neurosensory disabilities and behavioural and educational problems and have decreased probability for an optimal transition into adulthood compared to term controls. Outcome data are of interest not only to healthcare professionals but also to parents, schoolteachers and society. The aim of this review is to describe the follow-up studies of seven populations of VLBW or EPT infants performed in Sweden and published between 1995 and 2009.

CONCLUSION

 The time has come to implement evident data from these Swedish follow-up studies into clinical practice and to perform regular and specific follow-up examinations during childhood for all VLBW and EPT children. These assessments, specially designed for high-risk infants, should consider the potential outcomes for neurological, visual, auditory function and cognitive function as well as behaviour and growth, from birth to school-start.

An evidentiary review regarding the use of chronological and adjusted age in the assessment of preterm infants

PURPOSE

The evidence supporting the recommendation to use age adjustment when assessing the growth, motor, and global development of premature infants was explored. Following a comprehensive literature search, 16 articles that compared the use of adjusted and chronological age were reviewed.

CONCLUSIONS

The use of full age adjustment based on the degree of prematurity was supported for the assessment of premature infants for a minimum of 12 months adjusted age.

PRACTICE IMPLICATIONS

The use of adjusted age enhances the ability to accurately recognize genuine delays as opposed to perceived delays related to a child's gestational age at birth.

Dental behavioural management problems and dental caries prevalence in 3- to 6-year-old Swedish children born preterm

BACKGROUND

Today, most children born preterm survive without major impairments. But high frequencies of cognitive and behavioural difficulties arise. Studies on dental behavioural management problems (DBMP) in these children are lacking. In addition, studies on caries prevalence are few and inconclusive.

AIM

This study aims to compare the frequency of behavioural problems and poor compliance with dental treatment in preschool children born preterm with those born full-term. The prevalence of caries was also studied.

METHODS

The study group included 187 children born between 23 and 32 weeks of gestation. The control group constituted full-term children matched by age, sex, immigrant background, and dental operator. DBMP, number of dental visits, missed appointments, and caries between ages 3 and 6 were noted.

RESULTS

At age 3, but not at age 6, the prevalence of DBMP at clinical examinations was significantly higher in preterm children compared with the control group. Of the children who received dental treatments during preschool years, preterm children displayed significantly more DBMP. No significant difference in dental visits or in caries prevalence was found. Preterm children, however, missed significantly more dental appointments.

CONCLUSION

Children born preterm display a higher prevalence of DBMP at dental examinations and treatments during preschool years.

Quality of life of formerly preterm and very low birth weight infants from preschool age to adulthood: a systematic review

OBJECTIVE

The goal of this systematic review was to synthesize studies that examined the health-related quality of life of preschool- and school-aged children, adolescents, and young adults who were born preterm and/or at very low birth weight.

METHODS

We searched 7 databases up to September 2006 (Medline, PubMed, Embase, EBM Reviews, Cumulative Index of Nursing and Allied Health Literature, PsycINFO, and the Educational Resource Information Center) as well as gray literature sources. We independently screened studies and included them only if a quality-of-life outcome measure was used and findings compared preterm, very low birth weight, or extremely low birth weight infants with term or normal birth weight peers. We independently assessed the methodologic quality of each study by using criteria adapted from the Centre for Reviews and Dissemination.

RESULTS

Fifteen cohort or cross-sectional studies met the review criteria. In 6 studies of preschool-aged children, differences were found between study and control groups, suggesting that many preschool children born preterm or at very low birth weight perform more poorly than their peers in physical, emotional, and/or social functioning. Extremely low birth weight school-aged children had lower health utility scores compared with their peers, and similar results were found for adolescents. Parents of preterm and very low birth weight teens noted significantly poorer performance in their child's global health, behavior, and physical functioning, whereas the teenagers themselves did not. In young adulthood, differences in physical functioning remained, but subjective quality of life was similar to normal birth weight peers.

CONCLUSIONS

The effects of preterm birth/very low birth weight on health-related quality of life seem to diminish over time, which possibly reflects issues related to a child's report versus a parent-proxy report, differing definitions of health-related quality of life, and adaptation of individuals over time, versus true change in health-related quality of life.

A decade comparison of preterm motor performance at age 4

This was a prospective longitudinal study of two cohorts comprised of one full term and three premature infant groups born 10 years apart. Birth cohort, perinatal morbidity, and birth weight effects were investigated at age 4. Cohort 1 (1985-1989) had longer gestation, higher birth weight, and better Apgar scores than Cohort 2 (1996-1999), which had more intraventricular hemorrhage and bronchopulmonary dysplasia. Cohort and perinatal morbidity group, but not birth weight, predicted motor scores. Preterm Cohort 2 children had better oral motor, fine motor, and total motor scores, but lower visual motor integration scores than Cohort 1. Motor problems continue to affect preterm children at age 4, in particular those who experience perinatal morbidity, despite a decade of neonatal intensive care advancements.

Health-related quality of life among 3--4-year-old children born with very low birthweight

AIM

This paper reports a study comparing health-related quality of life at 3-4 years of age among children born with very low birthweight (<or=1500 g) to a group of non-very low birthweight controls, and to examine biological, environmental, demographic and health factors associated with quality of life of children born with very low birthweight.

BACKGROUND

Advances in modern medicine have increased the survival of infants with very low birthweight, but its impact on quality of life of children during preschool years has been less studied.

METHODS

The study sample included 118 children born with very low birthweight and 170 non-very low birthweight controls in Taiwan. Primary caregivers of the study children completed structured questionnaires during the period November 2002 to April 2003. Health-related quality of life was measured using the Mandarin version of the TZO-AZL Preschool Children Quality of Life instrument. This tool has four dimensions: physical, emotional, cognitive and social functions. Higher scores indicate better quality of life.

FINDINGS

Children born with very low birthweight had statistically significantly lower mean quality of life scores in all the four dimensions compared with controls. Among the former, those who had current physical health problems scored lower in all dimensions of quality of life. Primary caregivers with higher educational levels and increased ages of the children were associated with improved scores in the emotional and social functions. Birth gestational age was negatively associated with cognitive function. Length of stay in the neonatal intensive care unit was negatively associated with scores for the social function aspect of quality of life.

CONCLUSION

Regular monitoring of the quality of life among very low birthweight children is needed. Nurses need to assess the child's current health state, birth gestational age, and the primary caregiver's educational level in order to identify those who are at risk for low quality of life and intervene early.

Assessment of motor control using kinematics analysis in preschool children born very preterm

The aim of this study was to better understand the mechanisms underlying the motor difficulties encountered by children born very preterm (VPT) without major sequelae from preterm birth. We compared the organization of visuo-manual aiming in preterm and full term (FT) preschool aged children based on performance and kinematics data. Twenty preterm (4 females, 16 males) and 20 sex- and age-matched FT children were divided into two age groups (mean age: 3 years-4 months, and 5 years). Comparison of the performance data showed differences between the older preterm and FT children. Kinematics data revealed differences in movement control between the younger preterm and FT children. The younger FT children did not differ from the older children. In addition, there was an effect of age on both performance and kinematics data for the preterm children only. The pattern of results suggests difficulties in integrating sensory information for movement control in the preterm groups, leading to a delay in the development of visuo-manual coordination. Kinematics analyses may help identify children at risk for poor school performance.

Intellectual development in a Danish cohort of prematurely born preschool children: specific or general difficulties?

A national cohort of extremely low birth weight (ELBW) and/or extremely preterm (EPT) children and a term control group was followed up at the age of 5 years. The primary objective was to investigate whether premature birth had a global impact on cognitive functions or affected specific functions only. Assessment tools were Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), Movement Assessment Battery for Children (M-ABC), and subtests from the Neuropsychological Assessment 4-7 years (NEPSY). The mean Full Scale IQ (FSIQ) and M-ABC score of the index children were 1.1 and 1.2 SDs lower than that of the control children (p <.001). Most WPPSI-R subtests showed medium to large differences between index and control children, suggesting a global impact of premature birth on cognitive functions. For both unadjusted and FSIQ adjusted means, no significant group differences on tests of memory or executive function were observed (p >.1), suggesting little impact of premature birth on these specific functions. In this sample, cognitive difficulties in 5-year-old ELBW and/or EPT children tended to be associated with general intellectual difficulties rather than with specific dysfunctions; however, the implications of this finding are ambiguous due to substantial attrition on the NEPSY subtests.

A randomized, controlled trial of the effectiveness of an early-intervention program in reducing parenting stress after preterm birth

BACKGROUND

Preterm birth has been associated with increased parenting stress in early infancy, and some reports have found this to be a risk factor for later behavioral problems. There are, however, few studies and conflicting results. Information about the fathers is scarce.

OBJECTIVES

Our goal was to study the effects of an early-intervention program on parenting stress after a preterm birth until 1 year corrected age.

METHODS

A randomized, controlled trial was conducted including infants with a birth weight <2000 g treated at the University Hospital of North Norway Trust, which serves the 2 northern-most counties in Norway, to examine the effects of a modified version of the Mother-Infant Transaction Program on parenting stress measured by the Parenting Stress Index. A term control group was also recruited. The Parenting Stress Index was administered to the mothers at 6 and 12 months' corrected age and to the fathers at 12 months' corrected age. The intervention consisted of 8 sessions shortly before discharge and 4 home visits by specially trained nurses focusing on the infant's unique characteristics, temperament, and developmental potential and the interaction between the infant and the parents.

RESULTS

Seventy-one infants were included in the preterm intervention group, and 69 were included in the preterm control group. The preterm groups were well balanced. Seventy-four infants were included in the term control group. Compared with the preterm controls, both the mothers and fathers in the preterm intervention group reported significant lower scores in child domain, parent domain, and total stress on all occasions except the mother-reported child domain at 12 months. These differences were not related to birth weight or gestational age. The level of stress among the preterm intervention group was comparable to their term peers. Both parents in the intervention group reported consistently lower scores within the distractibility/hyperactivity, reinforces parents, competence, and attachment subscales compared with the preterm control group. There were no differences in mean summary stress scores between the mothers and fathers in the 2 preterm groups at 12 months, but the intraclass correlation coefficient was higher in the intervention group.

CONCLUSIONS

This early-intervention program reduces parenting stress among both mothers and fathers of preterm infants to a level comparable to their term peers. We are now studying whether this will result in long-term beneficial effects.

Comparison of chronological and corrected ages in the gross motor assessment of low-risk preterm infants during the first year of life

OBJECTIVE: To evaluate the need of chronological age correction according to the degree of prematurity, when assessing gross motor development in preterm infants, during the first year of life. METHOD: Cohort, observational and prospective study. Alberta Infant Motor Scale (AIMS) was used to evaluate 43 preterm infants with low risk for motor neurological sequelae, during the first year of corrected age. Mean scores were analyzed according to chronological and corrected ages. Children with motor neurological sequelae were excluded during follow-up. RESULTS: Gross motor mean scores in preterm infants tended to be higher when corrected age was used compared with those obtained when using chronological age, during the first twelve months. At thirteen months of corrected age, an overlapping of confidence intervals between corrected and chronological ages was observed, suggesting that from that period onwards correction for the degree of prematurity is no longer necessary. CONCLUSION: Corrected age should be used for gross motor assessment in preterm infants during the first year of life.

[Primitive reflex in premature healthy newborns during the first year]

A non-controlled, prognostic cohort study was performed with the aim of establishing markers of neurological development and defining a clinical and epidemiological profile of preterm newborns at 3, 6, 9, and 12 months of gestation-corrected age in terms of primitive reflexes evolution.

RESULTS

At 3 months old of corrected age, all primitive reflexes were present. At 6 months old, all children showed plantar grasp and 2.7% still showed Moro and palmar grasp. Plantar grasp was the unique primitive reflex found at 9 and 12 months of corrected age.

CONCLUSION

It was possible to evaluate the occurence, as well as the disappearing of primitive reflexes in preterm newborns. The results show delay in the disappearing of primitive reflexes even with the use of corrected age.

Fetal infants: the fate of 4172 infants with birth weights of 401 to 500 grams--the Vermont Oxford Network experience (1996-2000)

OBJECTIVE

Improvement in the survival of extremely low birth weight infants requires that we evaluate the limits of our care and assess the impact of treatment on a population of infants who previously rarely survived.

METHODS

A review was conducted of demographic and clinical data of infants who had birth weight 401 to 500 g and were entered in the Vermont Oxford Network Database between 1996 and 2000.

RESULTS

A total of 4172 infants who weighed 401-500 g (mean gestational age: 23.3 +/- 2.1 weeks) were born at 346 participating centers. Overall, 17% survived until discharge. A total of 2186 (52%) died in the delivery room (DR), and 1986 (48%) were admitted to a neonatal intensive care unit (NICU). Compared with infants who died in the DR, infants who survived the DR and were admitted to the NICU were more likely to be female (58% vs 49%), to be small for gestational age (56% vs 11%), to have received prenatal steroids (61% vs 12%), and to have been delivered by cesarean section (55% vs 5%). Thirty-six percent of NICU admissions survived to discharge. Mean gestational age of the 690 NICU survivors was 25.3 +/- 2.0 weeks. These survivors experienced significant morbidity in the NICU.

CONCLUSIONS

An appreciable number of these marginally viable fetal infants survive. They experienced a high rate of serious morbidities while in the NICU. There is very little information about long-term outcomes, as the medical and developmental status of few of these infants has been followed carefully. Parents should be made aware of the high incidence of serious problems, and concerted efforts should be made to follow the status of these infants.

[Prognostic factors for cognitive development of very low birth weight premature children]

OBJECTIVE

Very low birth weight premature children often show cognitive development abnormalities. There is scarce information about the outcome of these children at preschool age in Brazil. The objective of the study is to describe the cognitive development of a population of premature newborns and to assess possible prognostic factors for abnormalities.

METHODS

A cohort study was conducted in a preschool children population whose subjects were very low birth weight premature babies born between January 1991 and September 1993. WPPSI-R Test was used for cognitive evaluation and it was applied by psychologists. Two cut-offs were set to describe abnormality: scores below 1 and 2 standard deviations (SD).

RESULTS

Seventy-nine children aged 4 and 5 years were studied. The mean full WIPPSI-R score was 75.6 (+/-11.9). The incidence of abnormal 1 and 2 SD full score was 77.2% and 32.9%, respectively. After adjusting for the method of delivery, small for gestational age (OR=6.19, 95% CI 1.60-23.86), abnormal cerebral ultrasound exam (OR=5.90, 95% CI 1.04-9.83) and male sex (OR=3.20, 95% CI 1.32-26.35) were predictors of full score <70.

CONCLUSIONS

Compared to the literature, these children showed a more severe cognitive development impairment. Small for gestational age, abnormal cerebral ultrasound exam and male sex were prognostic factors for worse outcome.

Quality of life of 6-year-old survivors from a regional neonatal unit

OBJECTIVE

Quality of life (QOL) of children who required treatment in a national neonatal intensive care unit (NICU) during the first week of life was determined at 6 years of age.

METHOD

QOL was assessed using a standardized questionnaire employing a multi-attribute scoring system including the functions: hearing, vision, speech, mobility, emotion, learning, self-care and pain. After excluding those with congenital neurodevelopmental disorders, questionnaire returns were analyzed from 177 children treated in the NICU in 1990 and a comparative age-matched group of 230 children who did not require neonatal care. Of these, returns were obtained from 143 (81%) cases and 171 (74%) of the non-treated group.

RESULTS

There was no difference in overall ability between the two groups, with 95 (66%) of cases and 126 (74%) of the comparison group reporting normal scores in all functions. Children treated in the NICU had decreased scores in individual functions including speech (p = 0.04), mobility (p = 0.009) and self-care (p = 0.006). For the study population, males had lower function in speech (p = 0.04) and learning (p = 0.001), with significantly worse function overall (p = 0.02) when compared with female cases. When compared with same-gender children who did not require NICU care, overall function was also significantly worse for male but not female cases (p = 0.0002), and this was largely contributed to by impairment in speech (p = 0.03), mobility (p = 0.04), learning abilities (p = 0.02) and self-care (p = 0.03). Eleven (7.7%) cases compared with just two (1.2%) children who were not treated in the NICU required assistance at school (p = 0.009). No difference was observed when QOL was assessed according to gestational age and birth weight.

CONCLUSION

Using a simple scoring system this study has shown that, for survivors who required early neonatal intensive care, the QOL at 6 years compared favorably with that of children not treated in the NICU, especially for girls.

Health-related quality of life of preterm children and their caregivers

As advances in medical science have extended the limit of viability downward to 23 or 24 weeks gestation, interest has turned from long-term health outcomes to quality of life for survivors. During the last decade, the first studies of the health-related quality of life (HRQOL) of children and young adults who were born extremely preterm were published. Taken from the fields of anthropology, economics, sociology, and psychology, the foundation of HRQOL is formed by theories of functionalism, positive well-being, and utility. HRQOL can be defined as the physical, psychological, and social domains of health, which can be influenced by an individual's experiences and perception. HRQOL instruments are generally composed of multiple domains and measure physical functioning, mental health, and social role functioning in some form. Utilities, or preferences for health outcomes under conditions of uncertainty, are also used. Studies of HRQOL to-date indicate that preterm children have, on average, poorer health than their normal birthweight peers, but the majority do not perceive their quality of life as significantly different than others of their own age. Measures of HRQOL should not replace the traditional measures of morbidity, but should become part of the standard battery of tools used to assess a preterm child's health and well-being. Ultimately, studies of the HRQOL of preterm children should identify aspects of life, physical, psychological, or social, that could be improved with intervention.

Tracheostomy and home ventilation in children

The last 30 years have brought a significant emphasis on home care for ventilator-dependent children. While the movement was driven by the desire to minimize healthcare costs, the advancements in medical knowledge and technology, and the change in the perception of a ventilator-dependent child have offered a fertile environment for the development of programs that support the chronic care of ventilator-dependent children at home (N. Engl. J. Med. 309(21) (1983) 1319; J. Pediatr. 106(5) (1985) 850; N. Engl. J. Med. 310(17) (1984) 1126; JAMA 258(23) (1987) 3398). In addition, the advances in medical and nursing care have led to the steady increase in the number of children with chronic respiratory failure and development of multi-disciplinary teams experienced and dedicated to the care of these children. Another trend that has also contributed to the rise in the number of pediatric patients using long-term mechanical ventilation is the parental expectation of long-term survival of their child. This parental expectation continues to grow as the effect of long-term mechanical ventilation on quality of life and longer survival becomes more evident. The primary indication for use of home mechanical ventilation is chronic respiratory failure (CRF) as indicated by hypoxemia and or hypercapnia. CRF is considered to be a condition persisting for greater than 1 month and requiring mechanical ventilation during part or all of the day to provide adequate gas exchange for the support of vital function (Chest 103(5) (1993) 1463).

Perinatal risk factors for schizophrenia: diagnostic specificity and relationships with maternal psychopathology

Although a growing body of evidence supports the hypothesis that exposure to obstetric complications (OCs) increases the vulnerability for schizophrenia, some questions remain unanswered regarding the diagnostic specificity and the etiological significance of this association. Associations with a history of OCs have been reported for other severe psychiatric disorders, such as autism, anorexia nervosa, or psychotic affective disorder. Thus, OCs may increase in a relatively non-specific way the vulnerability for a range of severe mental disorders, the expression of this vulnerability depending on the interaction between OCs and other risk factors, such as the genetic liability for specific psychiatric disorder, or exposure to later environmental risk factors. The causal pathway between OCs, maternal psychopathology, and psychotic outcome in the offspring is not fully elucidated. The directions of the associations are often bi-directional, and the mediating variables, if any, are not clearly identified. OCs may have a direct negative impact on fetal brain development, may be on the causal pathway between prepartum maternal depression/exposure to stress and increased risk of schizophrenia, or may indirectly increase the risk of child's later psychiatric disorder by acting as risk factors for maternal postpartum depression. The links and possible interactions between somatic perinatal risk factors and maternal psychopathology in the association with offspring's increased vulnerability for psychosis have to be further explored.

Early developmental outcomes after newborn encephalopathy

OBJECTIVE

The aim of this study was to ascertain the early developmental status of children who have a history of newborn encephalopathy.

METHODS

A longitudinal follow-up was conducted of a population-based, case-control study of children born in Western Australia between June 1993 and December 1996. The study included 276 term children (>/=37 weeks' gestation) with moderate or severe newborn encephalopathy and 564 unmatched term control subjects. The Griffiths Mental Development Scales was used to ascertain developmental status and a General Quotient (GQ) score. Outcome measures were the Griffiths developmental subscales, GQ, diagnosis of cerebral palsy, and mortality.

RESULTS

Thirty-four patients and 1 control subject died before reaching assessment. Between June 1994 and December 1999, 195 (81%) eligible patients and 445 (79%) eligible control subjects were assessed. Statistically significant differences were found between patients and control subjects for GQ and all developmental subscales. Overall, 39% of patients had a poor outcome as defined by death, cerebral palsy, or a significant degree of developmental delay, compared with 2.7% of control subjects. Furthermore, 62% of those with severe encephalopathy had a poor outcome compared with 25% of those with moderate encephalopathy. Patients with a history of seizures were 3 times more likely to develop cerebral palsy than patients without. Overall, 28 (10.1%) of patients have cerebral palsy.

CONCLUSIONS

These data provide important prognostic information regarding survival and serious disability and indicate that newborn encephalopathy places children at significant risk of developmental delay by their second year. These findings also suggest that comprehensive clinical and educational assessments are required to enable appropriate educational provisions as these infants approach school entry.

Biological contributions to the presentation and understanding of attention-deficit/hyperactivity disorder: a review

Attention-deficit/hyperactivity disorder (ADHD) is the most commonly diagnosed disorder in children today with estimated prevalence rates falling between 3 and 5% of children (American Psychiatric Association, 1994). From inception, research has focused on studying varying facets of this disorder with initial efforts primarily focusing on treatment outcome. However, prominent efforts have been made in recent research efforts to shed light on the etiology of this disorder. Such research has discovered the contribution of genetic inheritance, as well as environmental factors that lead to the development of this disorder. Furthermore, studies using neurological and neuropsychological assessment measures have implicated the involvement of various Parts of the brain. This article critically reviews this body of research in light of its impact on the current specific neuropsychologically based etiological theories, as well as the most beneficial directions for future research.

Longitudinal follow-up of children born preterm: cognitive development at age 19

In a long-term prospective study, 39 preterm children born before 35 completed weeks of gestation and 23 full-term children were followed up at 4, 9 and 19 years of age. Psychometric evaluation of the cognitive development at 4 years of age showed that the preterms fell within the normal range, although their performance was inferior to that of the full-terms. This difference between the groups was not found at 9 and 19 years of age. Within the preterm group there was no correlation between the test results and birthweight, gestational age, prenatal or perinatal optimality scores. Full-terms had better scholastic performance at the end of compulsory schooling, while there was no difference at 19 years of age. At 19 years of age, about 1/3 of the children in both groups rated themselves as having had attention deficits during their childhood and adolescence. In this group of moderately immature, low-risk children, preterm birth without major physical or mental disabilities poses a developmental risk that seems to have the greatest impact during the preschool years and then gradually attenuates.

Visual-motor function of very low birth weight and full-term children at 3 1/2 to 4 years of age

Improvements in perinatal and neonatal management have not only led to a higher survival rate of very low birth weight infants (VLBW; < or = 1,500 g or < 32 weeks gestational age), but also to a better outcome of these children. However the percentage of VLBW children who need special education because of later school problems remains high even in children considered neurologically normal during infancy. We assessed 40 VLBW children and 83 healthy full-term children at age 3 to 4 years by means of a simple and short test for visual-motor deficits. The test included the copying and cutting-out of geometric shapes, the building of models, the recognition of colours and the observation of the concentration and cooperation during the test. All VLBW children had had a good perinatal outcome and had been considered neurologically normal at one year of age. Most VLBW children scored within 1 standard deviation (S.D.) of the test mean, but on average the VLBW children scored significantly lower than the full-term infants in the copying of figures, the cutting-out of geometric forms, the building of models and in the overall concentration and cooperation during the test. Children who attended a nursery school achieved significantly better test results. Girls tended to have better results, but this was not statistically significant. Social factors and age had a significantly greater impact on results than perinatal factors. In summary, VLBW children scored significantly less in almost every test item compared to their term peers. Our test battery could serve as a short introductory test to screen for deficits in visual-motor skills, especially in VLBW children.

Ethnic differences in the growth of low-birthweight infants

Differences in growth were investigated among ethnic groups in low-birthweight babies (< 2500 g or < 32 weeks gestation) at birth and at 2-3 years. This prospective study was based on data for all 3091 low-birthweight live births in the South East Thames Region, UK, over a 1-year period, surviving to discharge from hospital. Weights were recorded at birth and at 2-3 years for 998 babies, and head circumferences for 859. These were compared with the UK 1990 reference standards. Ethnic differences were adjusted for parity, multiple birth, smoking and alcohol during pregnancy, mother's height, weight and age, marital status, partner's support and social class. At 2-3 years, there was substantial average catch-up growth only for the weight of infants of > or = 32 weeks' gestation. Babies < 32 weeks gestation had fallen behind. Head circumferences had failed to keep up or had fallen behind for both groups. The ethnic groups had similar birthweight standard deviation scores (SDS). At 2-3 years, Black babies of < 32 weeks' gestation had gained in weight and head circumference compared with White babies (adjusted difference in weight SDS: 0.71, [95% CI 0.28, 1.13]). Asian babies of at least 32 weeks' gestation had smaller heads than White, a difference that increased with time. It was concluded that ethnic differences in the growth of low-birthweight infants are related to gestational age. Although most of the babies born at < 28 weeks' gestation were close to their birthweight reference standards, only the Black infants had maintained their position at 2-3 years. Black infants, particularly when born preterm, tend to put on more weight than White.

Neuromotor ability in 5- to 7-year-old children with very low or extremely low birthweight

This study was intended to determine the effects of extremely low birthweight (ELBW, 500 to 999 g) and very low birthweight (VLBW, 1000 to 1499 g) on neuromotor ability in 5- to 7-year-old children. Fourteen ELBW and 20 VLBW children were compared with 24 term control children of normal birthweight (NBW, >2500 g). Using quantitative assessment instruments, the following data were collected: maximal cycling speed during 30 seconds of cycling at 'zero' resistance, simple reaction time of the legs, and performance on components of a whole-body coordination test. The main findings were a slower reaction time, lower maximal cycling speed, and lower coordination scores in the ELBW group compared with the NBW group and, for some variables, with the VLBW group. The reduced motor performance in these children appears for the most part to be a reflection of impaired neuromotor control and motor development, rather than merely a smaller body or muscle size.

Neurodevelopment until the adjusted age of 2 years in extremely low birth weight infants after early intervention--a case-control study

A total of 104 infants with birth weights of less than 1000 grams were enrolled in this prospective case-control study in order to examine the effect of occupational therapy based on sensory integration (SI) and neurodevelopmental therapy (NDT) on neurological development. The children were grouped as matched pairs on the basis of a set of developmental risks assessed at the age of 3 months. The intervention children had a weekly session of 60 minutes of occupational therapy from the corrected age of 6 months up to 12 months. All the children were examined at the corrected age of 3, 6, 9, 12, 18 and 24 months. The neurodevelopment of the cases and the controls did not differ essentially and the only significant difference was found in the social development of the children at the age of 12 months to the advantage of the intervention group. It is concluded that this amount of occupational therapy in at-risk children does not have a relevant effect on neurological development.

Birth weight and physical ability in 5- to 8-yr-old healthy children born prematurely

Recent advances in perinatal care have resulted in increased survival rates of extremely small and immature newborns. This has resulted in some neurodevelopmental impairment. The purpose of this study was to quantitatively evaluate and compare neuromuscular performance in children born prematurely at various levels of subnormal birth weight (BW). Subjects were 5- to 8-yr-old children born prematurely at different levels of subnormal BW (535-1760 g, N = 22, PM), and age-matched controls born at full term (> 2500 g, N = 15, CON). None of the subjects had any clinically defined neuromuscular disabilities. Body mass (BM) of PM was lower than that of CON (18.3 +/- 2.7 vs 21.7 +/- 3.8 kg) with no difference in height or sum of 4 skinfolds. Peak mechanical power output determined with a 15-s modified Wingate Anaerobic Test and corrected for BM was lower (P = 0.07) in PM than in CON (5.11 +/- 1.07 vs 5.94 +/- 1.00 W.kg-1). This was especially noticeable in children born at extremely low BW (ELBW, < 1000 g, 4.49 +/- 1.04 W.kg-1, P < 0.01). Peak power, determined in a force-plate vertical jump, corrected for BM was lower in PM vs CON (25.5 +/- 5.4 vs 30.8 +/- 5.2 W.kg-1, respectively P = 0.01), especially in the ELBW group (20.0 +/- 5.5 W.kg-1). Similarly, the elapsed time between peak velocity and actual jump take-off was longer in PM than in CON (41.2 +/- 9.4 vs 35.8 +/- 5.8 ms, respectively, P = 0.04). No differences were observed in peak force. The results suggest that performance deficiencies of prematurely-born children may be a result of inferior inter-muscular coordination. The precise neuromotor factors responsible for this should be identified by future research.

Etiology and pathogenesis of attention-deficit hyperactivity disorder (ADHD): significance of prematurity and perinatal hypoxic-haemodynamic encephalopathy

Attention-deficit Hyperactivity Disorder (ADHD), defined as a disorder of awareness with impulsivity, has lately been characterized as a dysfunction of the striatum (neostriatum = globus pallidus + putamen). This structure is in a unique position of contextual analysis and samples information samples information from almost the entire cortex through its spiny neurons. The etiology is heterogeneous, with genetic as well as lesional factors. Among the latter, pre- and perinatal events are prominent. Advances in the understanding of the role of fetal circulatory insufficiency with loss of autoregulation and systemic hypotension have drawn attention to the vulnerability of watershed regions, including the striatum. Not only circulatory facts are important for this selectivity, however. The anatomical characteristics, with convergent glutaminergic afferent synaptic transmission from almost the entire cortex contribute to the vulnerability in ischemia-induced liberation of glutamate: The striatum becomes the victim of its virtue. Repeated hypoxic-ischemic events are particularly common in prematurity, a fact which seems to explain the high incidence of ADHD in this patient group. The magnitude, of the problem is increasing with the increased survival rate among premature infants.