Motor trajectories from 4 to 18 months corrected age in infants born at less than 30 weeks of gestation

Background

Preterm infants are recognised as developing at a significantly slower rate than their full-term peers and with different movement quality.

Aim

This study aimed to describe the longitudinal gross motor trajectories of these infants in the first 18 months of (corrected) age and investigate factors associated with gross motor development.

Study design

A longitudinal study was conducted with convenience samples of 58 preterm infants born ≤ 29 weeks of gestation and 52 control full-term infants in Australia.

Outcome measures

The infants were assessed at 4, 8, 12 and 18 months of (corrected) age using the Alberta Infant Motor Scale (AIMS).

Results

Forty-six preterm and 48 control infants completed all four assessments. The preterm group scored significantly lower on various sub-scores at all age levels. Almost half of the preterm infants demonstrated less progression in the sit sub-scale from 4 to 8 months (corrected) age, possibly due to an imbalance between flexor and extensor strength in the trunk. At 12 and 18 months of (corrected) age, lack of rotation and fluency in their movements were evident in some preterm infants. Presence of intra-ventricular haemorrhage and chronic lung disease were associated with poor motor performance at 4 months and use of postnatal steroids was associated with poor motor performance at 4, 8 and 18 months of corrected age.

Conclusion

The imbalance between flexor and extensor muscle strength in preterm infants had a stronger impact on motor development than usually expected. The AIMS appears to be a sensitive assessment tool to demonstrate the unique movement characteristics in this preterm cohort.     

Declining cognitive development from 8 to 18 months in preterm children predicts persisting higher parenting stress

Background

Higher parenting stress in mothers of children born very preterm may be in part a response to poorer neurobehavioral development, reflecting realistic concerns in addition to adaptation to the trauma of preterm delivery. To our knowledge, there are few longitudinal studies of parenting stress that have addressed child cognitive competence.

Aims

To examine parenting stress in preterm and full-term children at 8 and 18 months corrected chronological age (CCA), in relation to child cognitive development and behavior.

Subjects

Participants were N = 152 children (98 preterm born ≤ 32 weeks gestation, and 54 full-term) seen at 8 and 18 months CCA, and the primary caregiver parent.

Study design/Outcome measures

The Parenting Stress Index questionnaire was completed by a parent, child interactive behavior was videotaped, and the Bayley Scales of Infant Development (BSID II, Mental Development Index; MDI) were administered at both ages.

Results

Total Parenting Stress was higher in preterm than full-term children at 8 and 18 months CCA (p < .02), accounted for primarily by the Child domain. Hierarchical regression showed (after controlling for neonatal risk, number of children in the home, child interactive behavior and maternal education) that decreasing Bayley MDI scores from 8 to 18 months CCA predicted higher parenting stress for preterm children. For full-term children, number of children in the home and child interactive behavior predicted parental stress at 18 months.

Conclusion

Higher parenting stress persisting to 18 months CCA in preterm children may partly reflect realistic parental concerns with their child's development.     

Is term newborn body composition being achieved postnatally in preterm infants?

Background

The American Academy of Pediatrics (AAP) recommends that preterm infants' growth duplicates fetal growth rates and that body composition replicates in utero body composition.

Aims

To compare the total body fat mass between preterm infants assessed at term corrected age and full-term newborns, and to investigate the effects of gestational age, gender, weight increase, being breast fed on total adiposity.

Study design

Prospective observational study.

Subjects

One hundred and ten preterm infants [mean (SD) gestational age: 29.9 (2.3) weeks; birth weight: 1118 (274) g], and 87 full term [mean (SD) 38.6 (1.21) weeks, 3203 (385) g], breastfed infants.

Outcome measures

Growth and body composition by means of a pediatric air displacement system were assessed at term corrected age in preterm infants and on day 3 of life in full term infants.

Results

Weight, length and head circumference were smaller in the preterm group as compared to the term group. Mean (SD) percentage of fat mass in preterm infants was significantly higher as compared to term infants [14.8 (4.4) vs 8.59 (3.71), P < 0.0001]. Fat mass was negatively correlated with gestational age (P < 0.001), and positively associated with weight increase (P < 0.05).

Conclusions

Our data suggest that body composition, in terms of fat mass, in preterm infants at term corrected age is different from that of full term newborns.     

Brain positron emission tomography in preterm and term newborn infants

Objective

To study the clinical values of positron emission tomography (PET) in preterm and term newborn infants through observing brain glucose metabolism by ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET.

Method

To observe the brain ¹⁸F-FDG PET imaging in 9 term and 7 preterm newborn infants in the same condition after administration of 0.1 mCi/kg ¹⁸F-FDG.

Result

The brain ¹⁸F-FDG PET imaging showed that the uptake of ¹⁸F-FDG was relatively more in the thalamus, and less in the cerebral cortex in preterm and term newborn infants. The uptake of ¹⁸F-FDG of cerebral cortex in preterm infants was less than that in term infants, so the structure of brain ¹⁸F-FDG PET imaging was a little fainter in preterm neonates as compared with that in term newborns.

Conclusion

¹⁸F-FDG PET imaging could show different glucose metabolisms of brain in preterm and term infants. Brain ¹⁸F-FDG PET imaging might be a useful tool for estimating the brain function in newborn infants, and its clinical values need further investigation.     

Parental bilingualism is associated with slower cognitive development in very low birth weight infants

Background

Speech development is frequently impaired in very low birth weight (VLBW) infants. Few and controversial data have been published on concepts regarding the influence of bilingual education.

Aims

The objectives of the current study were to assess the influence of parental bilingualism on speech development and neurodevelopmental outcome in low risk VLBW infants.

Study design

Monocentric prospective controlled cohort study with standardized follow-up.

Subjects

We recruited 50 singleton VLBW infants each from monolingual and bilingual families as well as 90 term control infants. The infants were free of disease and congenital malformation.

Outcome measures

Griffiths scales of infant development at the corrected ages of 6 and 12 months, Bayley Scales of Infant Development II (BSID II) with 22 months.

Results

In general, both bilingual and monolingual VLBW infants achieved age-specific milestones at the corrected age of 6, 12 and 22 months. However, bilingual VLBW infants achieved significantly lower scores than their monolingual peers in all cognitive subscales. The influence of maternal education on the neurodevelopmental outcome of the preterm infants was not significant; the subscales' correlation with socioeconomic or biological parameters was poor. However, a clear differentiation between social status and bilingual environment importance for speech development was not possible.

Conclusions

In the setting of the present investigation, parental bilingualism is associated with slower neurodevelopment in VLBW infants during the first 2 years of life.     

CPAP combined with inhaled nitric oxide for treatment of lung hypoplasia and persistent foetal circulation due to prolonged PPROM

Background

Second trimester preterm premature rupture of the membranes (PPROM) before 24 weeks of gestation is associated with a high morbidity and mortality rate.

Aim

To demonstrate the efficacy of early continuous positive airway pressure (CPAP) combined with inhaled nitric oxide (iNO) for treatment of preterm infants with lung hypoplasia and persistent foetal circulation (PFC) due to very early PPROM and prolonged severe oligohydramnios.

Methods

Seven infants with prolonged PPROM, lung hypoplasia, respiratory distress and persistent foetal circulation were intubated in the delivery room for subsequent surfactant and iNO application. As our new treatment strategy was to keep the period of mechanical ventilation as short as possible, all infants were switched on nasal CPAP combined with iNO within the first 24 hours.

Results

Mean gestational age at PPROM was 19 + 6 weeks (range 14 + 2 to 23 + 6 weeks) and the average latency period between rupture of membranes and delivery was 10 + 3 weeks (7 + 3 to 16 + 4 weeks). Infants were born at 30 + 3 weeks of gestation (28 + 3 to 33 + 1 weeks) with an average birth weight of 1468 g (884 to 2200 g). In all neonates CPAP combined with iNO reversed PFC and 6 patients stabilised without the need for reintubation and mechanical ventilation. One infant had to be reintubated following 12 hours of CPAP combined with iNO due to respiratory insufficiency. All seven infants survived to discharge.

Conclusion

CPAP combined with iNO might be a promising approach for therapy of preterm infants with lung hypoplasia and persistent foetal circulation due to very early PPROM.     

Sodium Alginate (Gaviscon®) does not reduce apnoeas related to gastro-oesophageal reflux in preterm infants

Background

Apnoea of prematurity (AOP) frequently recurs in preterm infants. We have previously shown that a significant but variable proportion of AOP is induced by gastro-oesophageal reflux (GOR).

Aim

The aim of this study is to evaluate the efficacy of sodium alginate in reducing the frequency of GOR-related AOP.

Subjects

Twenty-eight preterm infants with AOP were studied by a six-hour recording of combined multichannel intraluminal impedance and pH monitoring and polysomnography, including two three-hour postprandial periods: sodium alginate was given after one single meal named as drug-given (DG) meal, while the other as drug-free (DF).

Results

During 165 h of registration, 715 apnoeas were recorded, 368 after-DG and 347 after-DF (p = .99); furthermore, 851 GOR episodes were detected, 315 after-DG and 536 after-DF (p = .001). No differences in the number of AOP were found between DG and DF. A significant reduction in the number of acid GORs and in acid exposure was found during DG, while the administration of sodium alginate didn't influence non-acid GOR indexes. The frequency of GOR-related apnoeas didn't differ between DG and DF.

Discussion

Sodium alginate doesn't reduce the total number of AOP nor GOR-related apnoeas. On the other hand, it reduces acid GOR features, while it had no effect on non-acid GOR indexes.     

Prematurity, maternal posttraumatic stress and consequences on the mother-infant relationship

Objective

Premature birth is a stressful experience for parents. This study explores the links between maternal posttraumatic stress, maternal attachment representations of the infant and mother-infant dyadic interactions.

Methods

The study enrols 47 preterm (GA < 34 weeks) and 25 full-term infants. The Perinatal Posttraumatic Stress Disorder Questionnaire was administered to evaluate maternal posttraumatic stress symptoms. At 6 months of corrected age, maternal attachment representations of the infant were explored and coded with the Working Model of the Child Interview. Interactive characteristics were explored in a videotaped play session and coded with the Care Index.

Results

Full-term mothers were more likely to follow a “Cooperative” dyadic pattern of interaction with the infant and demonstrate Balanced representations of the infant. Preterm mothers with high posttraumatic stress symptoms were more likely to follow a “Controlling” dyadic pattern of interaction, with more Distorted representations. In contrast, preterm mothers with low posttraumatic stress symptoms were more likely to fall into a “Heterogeneous” group of patterns of dyadic interaction, with Disengaged representations. Interestingly, in Cooperative preterm dyads, only 23% of the mothers demonstrated Balanced representations, despite rates of 69% in full-term Cooperative dyads.

Conclusion

Premature birth affects both mother-infant interaction characteristics and maternal representations of attachment with the infant. In particular, a “Controlling” dyadic pattern was associated with high maternal posttraumatic stress symptoms and Distorted maternal representations. It is important to examine the impact of maternal posttraumatic stress on the parent-infant relationship in order to plan supportive, preventive interventions in the neonatal period.     

Prognostic value of a scorable neurological examination from 3 to 12 months post-term age in very preterm infants: A longitudinal study

Aims and study design

The Hammersmith Infant Neurological Examination proved effective in predicting locomotor function in very preterm infants after 9 months of age. We performed the examination in a cohort of 103 very preterm infants (gestational age below 32 weeks) as early as 3 months' post-term age, and longitudinally at 6, 9 and 12 months. Our aim was to establish the frequency distribution of the optimality scores at each age period, to explore the predictive value of the examination from 3 months onwards as to developmental outcome and locomotor function at 2 years, and to explore its longitudinal consistency.

Results

The results showed that this standardized neurological examination can be performed in preterm infants as early as 3 months' post-term age to predict motor outcome at 2 years, and that its high predictive value is consistent across the first year of life due to an effective combination of different items for each age period.

Conclusions

We confirm the high predictive value of this neurological examination in very preterm infants after 9 months and extend it to the assessments performed as early as 3 months post-term. This is of great relevance as in very preterm infants early prediction of motor function is essential for a prompt planning of therapeutic interventions.     

Parenting stress in mothers of preterm infants during early infancy

Objective

Mothers of preterm infants during the first year of life may experience stresses greater that those found in mothers of term infants. The aim of the study was to determine the levels of parenting stress and psychological well-being in mothers of very preterm babies in comparison to a control group of term mothers.

Methods

One hundred and five mothers who delivered 124 babies at ≤ 30 weeks gestation were recruited together with 105 mothers who delivered 120 babies at term. At 4 months of age (corrected for prematurity for the preterm babies), the mothers completed the Parenting Stress Index Short Form, the Edinburgh Postnatal Depression Scale (EPDS), the Dyadic Adjustment Scale (DAS) and the Short Temperament Scale for Infants (STSI). The preterm and term groups were compared.

Results

Questionnaires were returned from 86 of the preterm mothers and 97 of the term mothers. The mean Total Stress score for the preterm and term groups was 67.0 and 63.79 respectively (P = 0.32) with 17% of the preterm and 9% of the term group having high scores (P = 0.135). There were no differences of the EPDS and the DAS between the groups. The temperament of the preterm infants was similar to the term infants. For both groups, scores on the EPDS, DAS and the STSI were independent predictors of Total Stress scores on multiple regression analysis.

Conclusion

Parenting stress in mothers of preterm infants during early infancy does not appear to be greater than that in mothers of infants born at term. For both groups of mothers, depression symptoms, marital satisfaction and infant temperament were independent risk factors for high levels of parenting stress.     

Circulating adipocyte fatty acid binding protein levels in healthy preterm infants: Positive correlation with weight gain and total-cholesterol levels

Background

Adipocyte fatty acid binding protein (a-FABP) has been suggested to play an important role in the pathogenesis of metabolic syndrome. Preterm infants are at risk for the later development of insulin resistance, and, possibly, other components of metabolic syndrome.

Aim

To determine circulating levels of a-FABP in preterm infants and examine possible associations of a-FABP with metabolic indices (serum lipids, glucose, and insulin levels, and homeostasis model assessment index of insulin resistance [HOMA-IR]), levels of leptin and adiponectin, anthropometric parameters and weight gain.

Study design

Prospective cohort study.

Subjects

55 healthy preterm (mean [SD] gestational age 32.8 [1.8] weeks) and 23 fullterm infants (reference group).

Outcome measures

Serum a-FABP, lipids, glucose, insulin, leptin and adiponectin levels at 31.9 [10.4] days of life.

Results

Serum a-FABP levels did not differ significantly between preterm and fullterm infants. A-FABP levels correlated positively with total-cholesterol [total-C] in both preterm and fullterm infants (β = 0.33; p = 0.01 and β = 0.33; p = 0.04, respectively). In addition to total-C, weight gain correlated independently with a-FABP levels in preterm infants (β = 0.36, p = 0.01).

Conclusions

An association between a-FABP levels and indices of insulin resistance was not present in infants studied. As the development of insulin resistance in children born prematurely is possibly associated with weight gain in early postnatal life, follow-up of our study population is necessary to demonstrate whether a-FABP levels, shown to correlate with weight gain in preterm infants, are a predictive marker for the later development of insulin resistance in these infants.     

High plasma cytokine levels, white matter injury and neurodevelopment of high risk preterm infants: assessment at two years

Background

Controversy exists regarding association of high levels of proinflammatory cytokines, neonatal morbidities and poor neurodevelopment outcome in very low birth weight infants.

Objective

To determine association between severity of early inflammatory response and neurodevelopment outcome in high risk very low birth weight infants.

Methods

Sixty-two very preterm infants with high risk for early-onset sepsis were followed up to 24 months corrected age. Blood sample was collected for IL-6, IL-8, IL-10, IL-1β, and TNF-α analysis. Neurodevelopment outcome by Bayley Scales of Infant Development II was assessed at 22 to 24 months. Magnetic Resonance Image was performed at least once during the first 12 months.

Results

In 24 (38.7%) MDI was < 85, and 16 (25.8%) had PDI < 85. Low birth weight was significantly associated with low MDI, and birth weight and periventricular leukomalacia were significantly associated with low PDI by multiple regression analysis. After controlling for birth weight and gestational age, none of the studied variables was associated with low MDI, and only periventricular leukomalacia with low PDI. Each additional 100 g in the birth weight reduced the probability of low MDI and PDI scores in 14%.

Conclusions

There was no association of high cytokines plasma levels with poor neurodevelopment outcome at 22 to 24 months' corrected age, suggesting that elevations of plasma proinflammatory cytokines early in life do not play an important role in pathophysiology of brain injury in high risk preterm infants.     

Quantitative electroencephalographic patterns in normal preterm infants over the first week after birth

Background

Currently available tools to assist clinicians with prediction of neurodevelopmental outcome of preterm infants are inadequate. Modified cotside electroencephalography (EEG) has the ability to produce quantitative electrophysiologic measures. These measures may be useful in future prediction of outcome.

Aim

To determine patterns of change in quantitative EEG measures in preterm infants during their first week after birth.

Design

Observational.

Subjects

Preterm infants born at less than 32 weeks completed gestation surviving to discharge with unremarkable serial ultrasound scans.

Outcome measures

Changes in continuity, amplitude and spectral edge frequency measures of EEGs obtained over the first week after birth.

Results

Results of EEGs performed using a novel EEG device on 63 infants are reported here. Their median (range) gestation was 29 (24-31) weeks and birthweight was 1235 (540-1980) g. Quantitative measures of EEG continuity increased over the first week after birth from 72 (25-99)% to 92 (54-100)% at the 25 μV threshold, and from 39 (10-87)% to 64 (34-75)% at the 50 μV threshold, both p < 0.0001. There was a related 32% increase in median amplitude from 5.8 (2.6-10.6) μV on day 1 to 7.6 (4.3-9.4) μV on day 4, p = 0.005. There was a trend for average spectral edge frequency to fall from 10.7 (9.3-12.9) Hz on day 1 to 9.9 (8.1-12.3) Hz on day 3, p = 0.06. Each gestational tertile showed similar patterns.

Conclusions

There are consistent changes in quantitative neurophysiologic measures over the first week after birth, and particularly measures of continuity over the first 4 days, in normal preterm infants.     

Assessment of risk factors for survival of neonates born after second-trimester PPROM

Objective

Assess fetal risk factors which impact survival of infants delivered after second-trimester PPROM.

Study design

Clinical records of 87 patients, who all had second-trimester rupture of membranes between 14 + 0 and 24 + 6 weeks of gestation treated January 1998 to July 2005 were reviewed regarding perinatal outcome. This study is based on 25 surviving infants.

Results

13 of these 25 infants died in the hospital. Survivors had a higher birth weight (p = 0.008) and higher Apgar scores after 5 min (p = 0.005) than those infants dying. No differences in UA pH, the need of catecholamines and no association between histological verified chorioamnionitis and early onset sepsis were seen between survivors and nonsurvivors.

Conclusion

Higher gestational age at birth, higher birth weight, the absence of histologically verified chorioamnionitis and 5 min Apgar scores of ≥ than 6 have positive prognostic value for survival of neonates delivered preterm after second-trimester PPROM.     

Placental pathology is associated with illness severity in preterm infants in the first twenty-four hours after birth

Background

Placental pathology is associated with long-term neurological morbidity. Little is known about the association of placental pathology and illness severity directly after birth in preterm infants.

Objective

To determine the association between placental pathology and illness severity in preterm infants during the first 24 h after birth.

Study design

Placentas of 40 preterm infants, born after singleton pregnancies (gestational age 25.4-31.7 weeks, birth weight 560-2250 g) were assessed for histopathology. Illness severity was measured using the Score of Neonatal Acute Physiology Perinatal Extension (SNAPPE). A high SNAPPE reflects high illness severity.

Results

Examination of the 40 placentas revealed: pathology consistent with maternal vascular underperfusion (MVU) (n = 24), ascending intrauterine infection (AIUI) (n = 17), villitis of unknown aetiology (VUE) (n = 6), foetal thrombotic vasculopathy (FTV) (n = 6), elevated nucleated red blood cells (NRBCs) (n = 6), and chronic deciduitis (n = 10). SNAPPE ranged from 1 to 53 (median 10). Infants with elevated NRBCs had a higher SNAPPE than infants without elevated NRBCs (median 30 vs. 10, p = 0.014). The same was found for the presence of FTV (median 30 vs. 10, p = 0.019). No relation existed between SNAPPE and the other placental pathologies.

Conclusions

Elevated NRBCs and FTV were associated with higher illness severity during the first 24 h after birth in preterm infants. Ascending intrauterine infection was not associated with high illness severity.     

Hypothalamic-pituitary-adrenal (HPA) axis function in 3-month old infants with prenatal selective serotonin reuptake inhibitor (SSRI) antidepressant exposure

Background

Prenatal exposure to stress and selective serotonin reuptake inhibitors (SSRIs) alter hypothalamic-pituitary-adrenal (HPA) stress reactivity in offspring, however, the effects of combined exposure to HPA activity in human infants is unknown.

Objective

To examine HPA basal levels and stress responsiveness in 3-month olds with prenatal exposure to SSRIs.

Methods

Salivary cortisol levels in infants of SSRI treated mothers (n = 31, mean exposure 230.2 ± 72.2 days) were compared with non-SSRI exposed (n = 45) infants in response to a challenge (infant-controlled habituation task) and under basal conditions in the late afternoon/early evening. Mode of feeding, to account for possible postnatal drug exposure via breast milk, as well as measures of pre and postnatal maternal mood, were included as covariates.

Results

Lower post-stress cortisol levels were observed in non-SSRI exposed/non-breastfed infants compared with non-SSRI exposed infants who were breastfed at 3 months of age. Stress reactivity patterns among SSRI exposed infants did not differ with mode of feeding. The cortisol reactivity slope (CRS) was significantly lower among non-SSRI exposed non-breastfed infants compared with non-SSRI exposed breastfed infants. Early evening basal cortisol levels were lower in SSRI exposed infants than in non-SSRI exposed infants, controlling for maternal mood and mode of feeding. Postnatal SSRI exposure (infant SSRI drug levels) via breast milk was not associated with stress or basal cortisol levels. Total cortisol, reflected by the AUC measure, did not differ significantly between exposure groups.

Conclusions

Prenatal SSRI exposure altered HPA stress response patterns and reduced early evening basal cortisol levels. Stress challenge HPA response differences only became apparent when the moderating effect of method of feeding was accounted for. These findings suggest an early “programming” effect of antenatal maternal mood, prenatal SSRI exposure and postnatal maternal care giving on the HPA system.     

Support for the global feasibility of the Ages and Stages Questionnaire as developmental screener

Objective

To investigate the psychometric properties of the Dutch version of the 48 months Ages and Stages Questionnaire (D_ASQ_48).

Design

Prospective cohort study of a community-based sample of children born in 2002 and 2003 whose parents filled out the D_ASQ_48 and a questionnaire on school status at 60 months. The ASQ was translated into Dutch and back-translated into English by three independent translators.

Setting

Well Child Centers covering 25% of the Netherlands.

Participants

Parents of 1510 preterm and 562 term children born in 2002-2003 attending routine Well Child visits at age 45-50 months.

Main outcome measures

Reliability, validity and mean population scores for D_ASQ_48 compared to other countries.

Results

Mean population scores for the D_ASQ_48 were mostly similar to those in the USA, Norway and Korea. Exceptions (effect sizes of difference > 0.5) were problem solving (USA) and fine motor (Korea). Reliability was good for the total score (Cronbach alpha 0.79) and acceptable for all domains (0.61-0.74). As expected, infants born at gestational age < 32 weeks, children from low income families, of low educated mothers, and boys were more likely to fail on several domains (odds ratios, OR ranging from 1.5 to 4.9). The only unexpected association concerned children from one-parent families. Sensitivity to predict special education at five years of age was 89% and specificity 80%.

Conclusions

The good psychometric properties of the Dutch ASQ_48 and the small differences when compared to other countries support its usefulness in the early detection of developmental problems amongst children worldwide.     

Postural control of pre-term infants at 6 and 12 months corrected age

Background

Pre-term infants are at high risk for motor disabilities. Postural control, the basis for motor development, develops rapidly during the first year of life. An early start to extra-uterine life with an immature motor system may influence a pre-term infant's postural control.

Aims

To identify important prognostic factors and determine the difference in postural control between full-term and pre-term infants.

Method

Medical records of 93 pre-term infants with birth weight of less than 1501 g (mean birth weight = 1136.03 ± 243.86 g; mean gestational age = 29.14 ± 2.78 weeks) were reviewed. Data was collected from the preemie clinical follow-up program at the National Cheng Kung University, Taiwan.

Results

Results demonstrated that pre-term infants had poorer postural control than full-term infants both at 6 and 12 months adjusted age, and that medical complication as measured by the Neonatal Medical Index was the best predictor of postural control in pre-term infants in the first year of life. In addition, our findings confirmed that the development of postural control at 6 months adjusted age predicts the development of postural control at 12 months adjusted age after controlling for prognostic factors.

Conclusions

Both biological and social environmental factors appeared to be associated with pre-term infants' postural control at 6 and 12 months adjusted age. The development of postural control at 6 months adjusted age predicted the development of postural control at 12 months adjusted age. This suggested the value of early follow-up examinations at 6 months adjusted age.     

Executive function deficit in preschool children born very low birth weight with normal early development

Background

Many studies showed that children born very low birth weight (VLBW) are at high risk of executive function (EF) deficit, including impulse control, working memory and cognitive flexibility. However, they did not exclude the influence of abnormal early development on EF deficit.

Aims

The aim was to investigate if six-year-old VLBW children with normal early development still have EF deficit.

Methods

The research was conducted in two groups. The VLBW group included 37 children at aged 6, with more than 70 of Bayley Scales of Infant Development-Second Edition (BSIDII) before aged 2. The normal group included 22 term children aged 6 who were born healthy and developed normally, with comparable IQ and social economic status. Five instruments, including Comprehensive Nonverbal Attention Test Battery (CNAT), Tower of London (ToL), Wisconsin Card Sorting Test (WCST), Knox's Cube Test and Digit Span Subtest of WISC-IV, were analyzed to evaluate four kinds of EF, including impulse control, planning, cognitive flexibility and working memory.

Results

The EF of VLBW group was significantly lower in independent t-test on the scores of planning in ToL, cognitive flexibility in WCST and nonverbal working memory in Knox's Cube Test. Yet, the inferiority in EF of VLBW group became less significant when ANCOVA analysis was used to adjust gestation age and birth weight.

Conclusions

Six-year-old VLBW children even with normal early development are still at risk of deficits in “planning”, “cognitive flexibility” and “nonverbal working memory” while the preterm factors, both gestation age and birth weight, were important covariant factors.     

Resting heart rate does not predict growth in preterm infants

Background

Previous reports indicate that preterm infants with higher baseline heart rate (HR) have greater weight gain than preterm infants with lower baseline HR. To verify this correlation and the potential utility of resting HR as a bench mark for risk of extrauterine growth restriction (EUGR), we studied preterm infants born between 32 and 36 weeks gestation. Earlier gestation infants (27 to 31 weeks) were included.

Methods

In retrospective chart review we collected heart rate (HR) and growth data on 156 infants between 27.0 and 34.0 weeks gestation from birth to hospital discharge.

Results

There was a significant increase in weight gain from day 10 of life in infants with higher resting HR compared to infants with lower resting HR. However, upon controlling for birth weight and gestational age, there was no significant relationship between HR and weight gain for any gestational age group of premature infants.

Conclusions

Contrary to previous reports, there was no significant relationship between HR and growth at any gestational age after controlling for birth weight and gestational age. It is important to continue to search for a clinical marker of risk for poor growth in preterm infants and to give an opportunity for nutritional interventions which may support better growth and developmental outcomes.