Neurodevelopmental profile at five years of children born at < or = 32 weeks gestation

Multi-domain cognitive impairments at school age in very preterm-born children compared to term-born peers

Background

Preterm infants are at risk for functional impairments in motor, cognitive, and behavioral development that may persist into childhood. The aim of this study was to determine the co-occurrence of cognitive impairments in multiple cognitive domains at school age in very preterm born children compared to term-born children.

Methods

Comparative study including 60 very preterm-born children (gestational age ≤ 32 weeks) and 120 term-born controls. At school age, we assessed intelligence with the WISC-III, and visuomotor integration with the NEPSY-II, verbal memory with the AVLT, attention with the TEA-ch, and executive functioning with the BRIEF. We investigated co-occurrence of various abnormal (<5th percentile) and suspect-abnormal (<15th percentile, including both suspect and abnormal) cognitive functions.

Results

At mean age 8.8 years, 15% of preterm children had abnormal outcomes in multiple cognitive functions (≥2), versus 3% of the controls (odds ratio, OR 4.65, 95%-confidence interval, CI 1.33–16.35). For multiple suspect-abnormal cognitive outcomes, rates were 55% versus 25% (OR 3.02, 95%-CI 1.49–6.12). We found no pattern of co-occurrence of cognitive impairments among preterm children that deviated from term-born controls. However, low performance IQ was more frequently accompanied by additional cognitive impairments in preterms than in controls (OR 5.43, 95%-CI 1.75–16.81).

Conclusions

A majority of preterm children showed co-occurrence of impairments in multiple cognitive domains, but with no specific pattern of impairments. The occurrence of multi-domain cognitive impairments is higher in preterms but this seems to reflect a general increase, not one with a pattern specific for preterm-born children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02641-z.

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.

Visuo-manual coordination in preterm infants without neurological impairments

The extent of and reasons for visuo-manual coordination deficits in moderate and late preterm born infants without neurological impairments are not well known. This paper presents a longitudinal study on the visuo-manual development of twelve preterm infants, born after 33-36 weeks of gestation without neurological complications, between the ages of 6 and 12 months. Visuo-manual integration and grasping were assessed using the Peabody Developmental Motor Scales, along with bimanual coordination and handedness tests. Visual function was examined once prior to the beginning of the study. Gross motor development was also evaluated every month. Preterm infants were compared to a control group of ten full-term infants according to corrected age. Compared to full-terms, the visual perception of preterm infants was close to normal, with only a measure of visual fixation lower than in full-terms. In contrast, preterm infants had delayed development of visuo-manual integration, grasping, bimanual coordination, and handedness even when compared using corrected age. Tonicity and gestational age at birth were the main variables associated to the delays. These results are discussed in terms of the possible factors underlying such delays. They need to be confirmed on a larger sample of preterm born children, and to be correlated with later development. This would allow developing markers of future neuropsychological impairments during childhood.

Memory processes in learning disability subtypes of children born preterm

The purpose of this study was to evaluate immediate auditory and visual memory processes in learning disability subtypes of 40 children born preterm. Three subgroups of children were examined: (a) primary language disability group (n = 13), (b) perceptual-motor disability group (n = 14), and (c) no learning disability diagnosis group without identified language or perceptual-motor learning disability (n = 13). Between-group comparisons indicate no significant differences in immediate auditory or visual memory performances between language and perceptual-motor learning disability groups. Within-group comparisons revealed that both learning disability groups performed significantly lower on a task of immediate memory when the mode of stimulus presentation and mode of response were visual.

Pattern visual evoked potential performance in preterm preschoolers with average intelligence quotients

BACKGROUND

Preterm infants are more likely to develop visual perceptual and visual-motor impairments. Visual perceptual deficiencies may contribute to significant difficulties in daily life, but few reports are available relating electrophysiological assessment of the visual system to spatial information problems in premature preschoolers with average intelligence quotients.

AIM

This study was designed to investigate preterm preschoolers' responses to various spatial frequencies of pattern reversal visual evoked potential (PRVEP) and compare them to normal children.

DESIGN

Participants were 20 very low birth weight (VLBW), 41 low birth weight (LBW) and 41 normal children who were 4 to 6 years old and were free from major disability and developmentally appropriate for gestational age at birth. They were evaluated using the Chinese population adaptation of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) and recorded PRVEP at five levels of spatial frequency (checkerboard pattern (check) sizes of 108', 54', 27', 13' and 7') using a VikingQuest-IV neuroelectrophysiological device (Nicolet, Madison, WI, USA).

RESULTS

Compared with normal children, the LBW and VLBW groups had significantly lower level in the tests of verbal, performance and overall intelligence quotients, particularly in performance, although the levels were within the average range. The PRVEP P100 wave latencies were significantly prolonged at all five degrees of spatial frequency in the VLBW group compared with the controls, while showing delay in the LBW with 13' and 7' check size. In the meanwhile, the amplitudes of P100 at all five spatial frequencies were significantly smaller in the VLBW and LBW groups than in the normal children. And VLBW group had even lower P100 amplitudes than the LBW group.

CONCLUSIONS

Preterm preschoolers with average cognition capability are at risk of defect in visual-spatial perception, especially when they are confronted with more complicated information. PRVEP may provide an objective and convenient measurement in detecting the problem of visual perception in children.

Predictive value of early motor evaluation in preterm very low birth weight and term small for gestational age children

BACKGROUND

Motor problems are common in children born preterm or small for gestational age.

AIM

To study the predictive value of early motor assessments for later motor skills.

SUBJECTS

Twenty-eight children born preterm with very low birth weight (VLBW: birth weight <or=1500 g), 57 children born small for gestational age (SGA: birth weight <10th centile) at term and 77 term-born controls with normal birth weight.

METHODS

The psychomotor development index (PDI) of the Bayley Scales of Infant Development was used as a measure of motor skills at age one, the Peabody Developmental Motor Scales (PDMS) at age five and the Movement Assessment Battery for Children (Movement ABC) at age 14. Low/borderline low scores were defined as <-2SD/-1SD (PDI) or <5th/15th centile (PDMS; Movement ABC).

RESULTS

In the VLBW group, motor problems in adolescence were identified both by low PDI (sensitivity: 0.80; 95%CI:0.38-0.96) and PDMS scores (sensitivity: 0.83; 95%CI:0.44-0.97). In the SGA and the control group sensitivity was poor for low PDI and moderate for low PDMS scores. However, in the SGA group, sensitivity increased when borderline low PDMS scores were used as cut-off (sensitivity: 0.75; 95%CI:0.41-0.93). Specificity of PDI and PDMS was high in all three groups.

CONCLUSIONS

Both PDI and PDMS may be valuable tools for early identification of motor problems in VLBW children, whereas PDMS best predicted motor problems in the two other groups. In all three groups, a normal motor examination at 1 and 5 years was highly predictive of normal motor skills at age 14.

Do visual impairments affect risk of motor problems in preterm and term low birth weight adolescents?

BACKGROUND

Increased prevalence of motor and visual problems has been reported in low birth weight populations, but the association between them is less studied.

AIM

To examine how visual impairments may be associated with the increased risk of motor problems in low birth weight adolescents.

METHODS

Fifty-one very low birth weight adolescents (VLBW), 56 term small for gestational age (SGA) and 75 term control adolescents, without cerebral palsy, were examined at the age of 14. Motor skills were examined by the Movement Assessment Battery for Children. Visual functions included visual acuity, contrast sensitivity, nystagmus, strabismus, stereoacuity, accommodation, convergence and visual perception (Visual-Motor Integration test). An abnormality score was calculated as the sum of visual impairments. We used odds ratio as an estimate of the relative risk of having motor problems.

RESULTS

The odds of having motor problems were 10.4 (95% CI: 2.2-49.4) in the VLBW group and 5.1 (95% CI: 1.0-25.8) in the SGA group compared with the control group. The odds of having motor problems in the VLBW group were influenced by all visual variables, and most by visual acuity, when we adjusted for these separately. The greatest reduction in OR was found when adjusting for the abnormality score (adjusted OR: 6.8; 95% CI: 1.3-34.5). In the SGA group the odds of having motor problems were relatively unaffected by the visual variables and the abnormality score.

CONCLUSIONS

Visual impairments influence motor problems in VLBW adolescents, whereas motor problems in SGA adolescents seem to be unaffected by visual impairments.

School performance of adolescents born preterm: neuropsychological and background correlates

In this longitudinal study the development of preterm and control children was followed from infancy until adolescence. School performance at the age of 16 in subjects born very preterm with a gestational age (GA) of <or= 32 weeks was compared with the performance of adolescents born full-term. None of the subjects had major disabilities. The study groups performed similarly in most school subjects, including mathematics, the second foreign language and the native language (Finnish). Subjects in the preterm group achieved significantly higher grade points in the first foreign language than control subjects. In particular, the difference was evident between the preterm and control boys. The extremely preterm group with a GA <or= 29 weeks did not differ from the more mature group with a GA between 30 and 32 weeks in terms of the school grade points. Verbal and performance scale IQs as assessed at the age of 9 were of primary importance in predicting school success in adolescence. The results suggest a good outcome, measured by school grade scores at 16 years of age, of the subjects born very preterm.

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.

Inter- and intra-modal matching in very low birth weight and small for gestational age adolescents

BACKGROUND

Motor problems in low birth weight children may be related to problems in sensorimotor integration processes. Specific tests of inter- and intra-modal matching have not been used in low birth weight populations.

AIM

Examine whether low birth weight adolescents have poorer performance in inter- and intra-modal matching than normal birth weight adolescents.

STUDY DESIGN

A population based follow up study of very low birth weight and small for gestational age children at 14 years of age.

SUBJECTS

Fifty-three very low birth weight adolescents (VLBW: birth weight < or =1500 g), 59 term small for gestational age (SGA: birth weight <10th centile) and 82 adolescents with birth weight > or =10th centile at term (reference group).

OUTCOME MEASURES

Inter- and intra-modal matching was assessed by a manual matching task and results were presented for the preferred and the non-preferred hand in the visual (inter-modal) and proprioceptive (intra-modal) condition.

RESULTS

VLBW adolescents performed poorer in inter- and intra-modal matching compared with the reference group. However, the results were mainly due to a higher number of adolescents with cerebral palsy (CP) and a low estimated intelligence quotient (IQ(est)) in the VLBW group. SGA adolescents showed poorer performance with their non-preferred hand compared with their preferred hand in both inter- and intra-modal matching, whereas adolescents in the reference group and VLBW adolescents with normal IQ(est) and without CP performed equally well with both hands.

CONCLUSION

VLBW adolescents with normal IQ(est) and without CP do not have major problems in inter- and intra-modal matching. The poorer performance with the non-preferred hand in the SGA group may suggest a specific effect of intrauterine growth retardation.

Increased number of febrile seizures in children born very preterm: relation of neonatal, febrile and epileptic seizures and neurological dysfunction to seizure outcome at 16 years of age

PURPOSE

In prematurely born population, a cascade of events from initial injury in the developing brain to morbidity may be followed. The aim of our study was to assess seizures in prematurely born children from birth up to 16 years and to evaluate the contribution of different seizures, and of neurological dysfunction to the seizure outcome.

METHODS

Pre- and neonatal data and data from neurodevelopmental examination at 5 years of 60 prospectively followed children born at or before 32 weeks of gestation, and of 60 matched term controls from the 2 year birth cohort were available from earlier phases of the study. Later seizure data were obtained from questionnaires at 5, 9, and 16 years, and from hospital records and parent interviews.

RESULTS

In the preterm group, 16 children (27%) exhibited neonatal seizures, 10 children (17%) had seizures during febrile illness and 5 children had epilepsy. Eight children had only febrile seizures, and 3 of these had both multiple simple and complex febrile seizures and neurodevelopmental dysfunction. None of the 8 children had experienced neonatal seizures, 6 had a positive family history of seizures, but none developed epilepsy. The children with epilepsy had CP and neurocognitive problems, and all but one had experienced neonatal seizures; two of them had also had fever-induced epileptic seizures. In controls 3 children (5%) had simple febrile seizures.

CONCLUSION

Children born very preterm have increased rate of febrile seizures compared to the controls. However, no cascade from initial injury via febrile seizures to epilepsy could be shown during the follow-up of 16 years. Symptomatic epilepsy in prematurely born children is characterised by neonatal seizures, major neurological disabilities and early onset of epilepsy.

Naming skills of children born preterm in comparison with their term peers at the ages of 9 and 16 years

The linguistic abilities of children born preterm at 32 weeks' gestation or earlier at Kuopio University Hospital during 1984 to 1986 were evaluated during successive phases of a prospective study. The study protocol included the Rapid Automatic Naming test and Wechsler Intelligence Scale for Children - Revised at 9 years of age and a modified Stroop Color-Word test and the Wechsler Intelligence Scale - Revised at the age of 16 years. Fifty-one children born preterm (26 males, 25 females) and 51 age-matched and sex-matched term controls (26 males, 25 females) were studied at the age of 9 years. At the age of 16 years, 40 children born preterm (19 males, 21 females) and 31 term controls (14 males, 17 females) participated in the study. The children born preterm scored significantly lower in two naming tasks than the controls at the age of 9 years. However, there was no difference between the study groups in naming skills at the age of 16 years or in verbal IQ in either study phase. Maternal education level was not associated with naming skills. Thus, the consequences of preterm birth seem to be minor in relation to linguistic skills during school age and diminish by adolescence.

Development and behavior of non-handicapped preterm children from a developing country

BACKGROUND

There are many studies, mainly conducted in industrialized countries, concerning developmental and behavioral outcomes of preterm children. However, little is known about the outcomes of preterm children from developing countries.

METHOD

Forty-three non-handicapped Turkish preterm children, 15 with very low birth weight and 28 with low birth weight at preschool age, as well as 36 term controls were compared on rates of developmental, emotional and behavioral impairments. Data were collected by review of hospital records and application of various questionnaires and inventories to both children and their parents.

RESULTS

Preterm children had significant delays in general development and significant rise in somatic complaints with unknown medical etiologies. The very low birth weight group also had significant delay in language and cognitive development. Parents of the preterm children displayed significantly higher rates of democratic attitudes. Developmental outcome was significantly associated with birth weight and authoritarian parental attitudes where behavioral outcome was significantly influenced by birth weight.

CONCLUSION

Presence of developmental delay is in accordance with existing data on the outcomes of preterm children from industrialized countries. An isolated increase in somatic complaints is an uncommon finding which might also be related to cultural factors.

Physical growth and neurodevelopmental outcome of nonhandicapped low-risk children born preterm

BACKGROUND

Outcome studies on the effects of prematurity are increasingly restricted to extremely immature infants with birth weight below 1000 g or gestational age below 26 weeks. In contrast, studies comprising low-risk preterm infants are rare.

AIM

To examine growth and neurodevelopmental outcome, 70 low-risk low birth weight (LBW) children without neurological impairment were followed from birth to 7 years of age. At 7 years of age, LBW children were compared to a matched control group born at term.

METHODS

Postnatal growth was measured at 20 months in the LBW group and at 7 years in LBW and control children. At 20 months, the LBW group was assessed with the Griffiths Scales. At 7 years, LBW and control children were assessed with a neuropsychological test battery comprising tests for language, visual-perceptual, visual-motor, fine and gross motor abilities.

RESULTS

At 7 years of age, the frequency of children with low (3rd-9th percentile) or subnormal (<3rd percentile) growth parameters was increased in the LBW group. The Mean Griffiths Developmental Quotient (DQ) of the preterm group was normal (102.3+/-8.4), and there were only two results below DQ 85. There was no difference between 49 children appropriate for gestational age and 21 small for gestational age (SGA) children. At 7 years of age, reduced mean test results in the range of -0.5 SDS were observed for language and visual-motor abilities in the preterm group. This was due to an increased frequency of LBW children with moderately (SDS -1.0 to -2.0 SDS) subnormal test results. Even for the slightly LBW group (2000 to 2499 g), poorer language abilities were confirmed.

CONCLUSION

All LBW infants, including low-risk populations, should be included in a follow-up program in order to detect deficits early in life and begin treatment before school entry.

Motor skills in adolescents with low birth weight

BACKGROUND

Minor motor problems have been reported in low birthweight children, but few studies have assessed motor skills in adolescents.

OBJECTIVE

To examine the prevalence of motor problems in adolescents with low birth weight.

METHOD

Fifty four very low birthweight (VLBW: birth weight < or = 1500 g), 59 term small for gestational age (SGA: birth weight < 10th centile), and 83 control (birth weight > or = 10th centile at term) children were assessed with the Movement assessment battery for children (Movement ABC) at the age of 14 in a population based study.

RESULTS

One in four VLBW children (odds ratio (OR) 9.3, 95% confidence interval (CI) 2.5 to 34.5) and one in six SGA children (OR 4.7, 95%CI 1.2 to 18.4) had motor problems compared with controls (3.7%). There were no sex differences in motor problems in the VLBW group, and the increased risk was consistent across the continuum of the Movement ABC. For SGA children, the increased risk of motor problems was particularly in manual dexterity in boys.

CONCLUSION

VLBW and SGA adolescents have increased risk of motor problems compared with control children.

Quality of motor performance in preterm and full-term 3-year-old children

BACKGROUND

A combined assessment of motor performance and behaviour (CAMPB) was introduced previously for use in a longitudinal study of children who needed neonatal intensive care (NIC) and were born very preterm (n = 68), moderately preterm (n = 81) and full-term (n = 77) and in a reference group of neonatally healthy full-term children (n = 72). Aim To follow up the quality of motor performance at 3 years of age in the above groups of children.

METHOD

A detailed assessment of motor performance and an assessment of co-ordination were performed according to the CAMPB protocol. The results were compared between the different groups of children, and the relation between the two ways of assessing quality of motor performance was examined.

RESULTS

The detailed assessment showed that the very preterm children had a significantly higher total score of deviations than any of the other gestational age groups of children. Also, some types of deviations were much more frequently observed in the very preterm children than in the other three groups. Some types of deviations were more often seen in children with pronounced incoordination than in children with no incoordination. The results from the two ways of assessing motor performance were strongly correlated.

CONCLUSION

At 3 years of age, NIC children born very preterm have a lower quality of motor performance than NIC children born at a higher gestational age and healthy children born at term. The two ways of assessing quality of motor performance proved useful in identifying children with deviations indicating minor motor impairments.

[A comparative study of the perceptual and motor performance at school age of preterm and full term children]

The objective of this study was to compare the perceptualmotor performance in school age children who were born preterm and full term. Two groups of children, ages 5 to 7, participated in this study. Group I had 35 children, from low-income families, born up to the 34 week of gestation and/or weight bellow 1500 g. Group II had 35 full-term children, matched by age, gender and socioeconomic status to the children in Group I. Children were tested on the Bender gestalt, the motor accuracy test and on balance and postural responses measures. The preterm group obtained significantly lower scores in the majority of the tests. These besides reinforcing the importance of the follow-up of preterm children up to school age, also indicate the need to stimulate the fine motor and postural control Devment, even among preterm children who do not show evidence of neurological impairment.

Kinematic quality of reaching movements in preterm infants

Many preterm infants may experience so-called minor developmental disorders; however, in general, the problems in motor behavior are not detected until school age. To introduce therapies aimed at the prevention of these problems, we need to increase our knowledge of motor function and dysfunction at early age. The present study focused on the organization of reaching movements in full-term and preterm infants without cerebral palsy. The reaching behavior of premature infants (n = 63) was assessed longitudinally at the corrected ages of 4 and 6 mo. Clinical assessments were made at 6 and 12 mo of age. On the basis of the infant's morbidity during the early stay in the neonatal intensive care unit, the preterm infants were allocated into a high-risk and a low-risk group. Results from a previous study in full-term infants (n = 13) were included. Kinematics of reaching movements in supine position were measured, and the analysis focused on movement velocity and movement units. A compound parameter of kinematic variables was created, reflecting the quality of reaching movements. The present study showed that at the age of 4 mo, low-risk preterm infants showed more often optimal reaching behavior than full-term and preterm high-risk infants. This better reaching performance was related to a better general motor and behavioral development during the first year of life. At the age of 6 mo, the advantage of the low-risk group in reaching behavior had disappeared and a disadvantage in the form of nonoptimal reaching behavior of the high-risk group emerged.

General Certificate of Secondary Education performance in very low birthweight infants

AIM

To compare children of very low birth weight with matched controls for their performance in the General Certificate of Secondary Education (GCSE).

METHODS

GCSE examination results of 167 children of birth weight < or =1500 g attending mainstream schools and without clinical disability and 167 individually matched classroom controls were analysed.

RESULTS

In 143 instances, both children of a matched pair were entered for examination in one or more GCSE subjects. The total points score obtained was greater in the comparison group than in the index cases (difference between means 4.45: 95% CI 0.95 to 7.94; p = 0.01). The mean point score per examination subject was also significantly greater in the comparison group than in the index cases (mean of differences 0.43: 95% CI 0.12 to 0.73; p < 0.01).

CONCLUSIONS

As the children were closely matched for school and several social variables, factors acting during fetal or early postnatal development of very low birthweight infants probably compromise performance in the GCSE examination to a greater extent than school or childhood social environmental factors.

Motor performance and behaviour in preterm and full-term 3-year-old children

AIM

To compare the motor performance and behaviour at 3 years of age of very preterm, moderately preterm and full-term children (n = 221), who needed neonatal intensive care (NIC), and of 72 neonatally healthy full-term children (reference group).

METHOD

A model for combined assessment of motor performance and behaviour (CAMPB) was used. The children's performance was assessed on the basis of observations and documentation of categories of co-ordination, attention and social behaviour included in CAMPB.

RESULTS

Significantly more very preterm children showed deviations in co-ordination than children in the other groups, and this difference was most evident in comparison with the reference group. No differences were found between the groups regarding attention and social behaviour during the assessment.

CONCLUSION

Very preterm children differ from moderately preterm and full-term children in their motor performance at 3 years of age. By means of CAMPB, individual children with pronounced incoordination were identified in all groups, and some of them also showed pronounced lack of attention.

Exercise and the child born prematurely

With the increase in survival rates of children born prematurely, issues related to their active pursuits and responses to exercise have been gaining increasing attention. In some preterm children with an extremely low birthweight, bronchopulmonary dysplasia or cerebral palsy exercise capacity may be limited, especially in tasks requiring good neuromotor coordination. Deficiencies in aerobic and anaerobic performance, strength and coordination may even occur in children without overt manifestations of a neuromuscular or pulmonary disease. However, as a rule, children born prematurely may engage in physical activities and competitive sports without limitations. Exercise is safe in almost all such children as long as precautions are taken to avoid exercise-induced bronchoconstriction. However, to date there are no studies that have determined the efficacy of training. A wide variety of activities should be encouraged in all children born prematurely at an early age, to support the development of skills and to compensate for the possible effects of their premature birth on coordination.

Cognitive development, temperament and behavior at 2 years as indicative of language development at 4 years in pre-term infants

This study focuses on the early temperamental (TTQ = toddler temperament questionnaire), behavioral (IBR = infant behavior record), and cognitive precursors of impaired language functioning in preschool-age pre-terms infants. The study group consisted of 63 pre-term infants with a mean birth weight of 1246 +/- 437 g born in 1989-1991 in the University Central Hospital of Helsinki. Children with major disabilities (CP or mental retardation) were excluded. At the age of 4 years, 22% showed impaired language function. Logistic regression analysis showed that the Bayley MDI score was the best predictor in identifying an increased risk for language impairment. Behavioral characteristics were more strongly associated with subsequent language impairment than temperament.

School-age consequences of birth weight less than 750 g: a review and update

Recent advances in perinatal care have led to the survival of increasing numbers of children born at the lower limits of viability. Children with very low birth weight (LBW; less than 1,500 g, 3 lb 5 oz) have been studied extensively. Findings document poorer outcomes relative to normal birth weight term-born controls in neurologic and health status, cognitive-neuropsychological skills, school performance, academic achievement, and behavior. This report reviews current knowledge regarding LBW children, with special emphasis on outcomes for children with birth weight less than 750 g (1 lb 10 oz). Results from an ongoing longitudinal study suggest a gradient of sequelae, with poorer outcomes in less than 750 g birth weight children compared to both 750 g to 1,499 g birth weight children and term-born controls. Children with less than 750 g birth weight fail to catch up with their peers over time and may even be at risk for age-related increases in sequelae. Outcomes are highly variable but related to neonatal medical complications of prematurity and social risk factors. Further research is needed to understand the etiology and neuropathological basis of sequelae, the long-term developmental implications of LBW, and treatment needs.

Mediators of behavioral problems in 7-year-old children born after 24 to 28 weeks of gestation

We tested the hypothesis that prematurity acts through its association with neuromotor and intellectual functioning to explain behavior problems at school age. Sixty-one extremely preterm (EP) very low birth weight (VLBW) children (< 29 wk and < 1,500 g) born in 1987-1990 and 44 normal birth weight children (NBW) (> 37 wk and > 2,500 g) were matched for age, sex, and socioeconomic status (SES). Mediator variables were evaluated at a hospital at 5 years and 9 months. Behaviors were evaluated at school at 7 years by peers, teachers, and parents. When compared with NBW children, EP/VLBW children had poorer IQ and neuromotor development. At school, EP/VLBW children were evaluated by peers as more sensitive/ isolated, and by teachers and parents as more inattentive and hyperactive than NBW. When mediators were introduced, the previously significant relation between prematurity and behavior problems disappeared. Hyperactive and inattentive behaviors were explained by a specific working memory factor for the latter, and by a general intellectual delay for the former, whereas sensitive/isolated behaviors were best explained by neuromotor delays. Inattentive behaviors were also related to family adversity. At school age, extreme prematurity had thus an indirect effect on behaviors via specific and nonspecific intellectual and neuromotor delays.

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.

Visual-motor, visual-perceptual, and fine motor outcomes in very-low-birthweight children at 5 years

The prevalence and severity of visual-motor deficits and the relation of visual-motor function to visual perception and fine motor skills was examined in a group of 83 neurologically and intellectually normal (IQ >84) very-low-birthweight (VLBW) children at age 5. Fifteen children (17%) had below average visual motor scores (<1SD below mean). While relatively few children (N=9) had below average scores in visual perception (11%), 58 (71%) had below average scores for fine motor skills. Nineteen (23%) were considered impaired (<1.5SD); of these, eight were severely impaired (<2SD). Fine motor scores were significantly lower in children who had been born <28 weeks' gestation, with hyaline membrane disease, or had required a longer period of ventilation. There was significant correlation between visual-motor and fine motor scores (r = 0.50, P < 0.001) and between visual-motor and visual perception scores (r = 0.42, P < 0.001). The implications of these findings and management of these 'normal' children need further research. Previous reports of visual-motor dysfunction in school-age VLBW children could be related to fine motor difficulties.

Neuropsychological analysis of the visuomotor problems in children born preterm at < or = 32 weeks of gestation: a 5-year prospective follow-up

Forty-six intellectually normal children born preterm (< or =32 weeks of gestation) without major neurological disabilities and a control group of term children matched for age, sex, and parental educational and occupational status were assessed at the age of 5 years using neuropsychological tests emphasizing perceptual and visuomotor functions. The results show that in terms of cognitive functions these preterm children are a very heterogenous group, but many of them still have problems in visuospatial and sensorimotor functions. The preterm children achieved lower mean scores in tests where coordination and voluntary control of hands in combination with tactile, kinaesthetic, and visuospatial perception were needed. They had most difficulty with drawing directions of lines and in integrating two or more forms. They also had problems with 3-dimensional constructions as well as visual perception of rotated shapes or slopes of lines.

Neurodevelopmental profile in low-risk preterm infants at 5 years of age

The goal of this study is to determine the neurodevelopmental profile of a group of low-risk preterm infants and to determine whether the potentially unfavourable outcome is due to a few infants with moderate to severe impairments or to a majority of infants with only slight impairments. In a prospective study 44 low-risk preterm infants, i.e. infants with a neonatal risk score indicating a favourable outcome, born between 25-34 weeks gestational age, and 18 healthy term infants were examined neurologically and tested neuropsychologically at 5 years of age. The more unfavourable outcome in the group of low-risk preterm infants compared with the term infants was largely attributable to a poorer outcome in 12 of the 44 low-risk preterm infants. The remaining low-risk preterm infants showed similar test scores compared with the term infants. From these results we conclude that the unfavourable neurodevelopmental outcome of low-risk preterm infants is due to moderate to severe impairment in a few low-risk preterm infants, rather than slight impairment in the majority. The low-risk preterm infants with an unfavourable outcome showed particular impairment on measures of visual-motor integration, concentration and auditory memory in combination with integrative functions.

Speech perception and speech comprehension investigations of pre-term newborns and high-risk neonates of pre-school age

The purpose of this study is to establish whether there is any connection between neonatal morbidity and speech perception and comprehension in children of pre-school age who have previously been treated as newborn infants in an intensive care unit. The test applied is a method invented in Hungary for the analysis of global hearing, speech perception and comprehension. The authors summarize the results of their follow-up studies of 52 children with respiratory disorders as newborns, some of whom were born as pre-term and some as full-term newborns with asphyxia. The children have been put into three groups according to their maturity and their birthweight. Newborns with hearing loss and mental retardation were excluded from this study. Of the various neonatal factors the results show: complications of delivery, birthweight, hypoxia, persistent ductus arteriosus, duration of ventilation and complications of respiratory treatment are found to be correlated to perception and comprehension. Incidences of poor achievement obtained in the most characteristic subtests have been compared among the different groups of newborns. The intelligence level of pre-school children is found to be closely correlated to speech perception and comprehension.

Diagnostic and predictive value of auditory evoked responses in preterm infants: I. Patient characteristics and long-term neurodevelopmental outcome

The diagnostic and predictive value of brainstem, middle latency, and cortical auditory evoked responses, obtained in the neonatal period, in 81 preterm infants was assessed in relation to neurodevelopmental outcome. Eighteen healthy term infants served as a control group. In this report the patient characteristics and neurodevelopmental outcome are presented. The preterm infants were neonatally classified according to risk category and gestational age. At 5 y of age the neurodevelopmental outcome was assessed based on neurologic and neuropsychologic evaluations. The neuropsychologic test results showed the highest IQ scores in term infants, intermediate IQ scores in low risk preterm infants, and lowest IQ scores in high risk preterm infants. The intermediate IQ scores in the low risk preterm group were due to significantly lower test scores in a small subgroup of low risk preterm infants. In a post hoc analysis 12 low risk preterm infants with an unfavorable outcome could be identified. The neuropsychologic test results of the remaining low risk infants showed no clear differences compared with the term infants. The results suggest that the unfavorable outcome of the low risk preterm group as a whole is due to moderate to severe impairment of the few, rather than slight impairment of the majority.

Neurophysiological assessment of brain function and maturation: I. A measure of brain adaptation in high risk infants

Neurophysiologic assessments using EEG/polysomnographic studies permit the clinician to recognize expected patterns of brain maturation in the healthy neonate. By comparison, one can detect encephalopathic behaviors of newborns who are medically at risk. Severe physiologic expressions of encephalopathy are associated with neuropathologic lesions on postmortem examinations, brain lesions documented on neuroimaging studies, and major neurodevelopmental sequelae of survivors. However, such patterns are observed for only a minority of high risk neonates; less severe encephalopathies occur more frequently in neonates without evidence of brain lesions on imaging studies who either recover from medical illness or who manifest no findings of neurological dysfunction. These subtle and persistent brain disorders are obviously more difficult to detect and grade. This is specifically relevant for preterm infants in whom various degrees of encephalopathy may exist, but whose physiologic behaviors must be distinguished form expected behavioral and neurophysiologic patterns of prematurity. Neonates may express brain dysfunction as altered rates of brain maturation, as compared with expected patterns for a given conceptional age. Neurophysiologic expressions of brain dysmaturity, either from prenatal and/or postnatal stresses, may actually occur in a substantially larger segment of the high risk neonatal population than has been anticipated. EEG-sleep studies can serve as a noninvasive neurophysiologic probe of brain organization and maturation to extend clinical observations to assess the severity and persistence of brain dysfunction in a neonate who may be at risk for later neurodevelopmental compromise.

Randomized study of the effect of antenatal dexamethasone on growth and development of premature children at the corrected age of 2 years

The objective of the series was to study the effect of prenatal dexamethasone therapy on the growth and neurological development of preterm children until the age of 2 years. Eighty-two children with a mean gestational age of 30 (24-33) weeks and a mean weight of 1291 (530-2360) g at birth, treated antenatally with either dexamethasone (n = 50) or placebo (n = 32), were examined at the adjusted age of 24 months by a paediatric neurologist, a neuropsychologist and a speech therapist. Neurological development was defined as normal if all scores of neuropaediatric, neuropsychological and verbal tests were within the normal range. Normal neurological development was found in 52% of the dexamethasone-treated and in 34% of the placebo-treated children. The incidence of cerebral palsy was 10% in the dexamethasone group and 22% in the placebo group. Minor developmental delay was found in 42% of dexamethasone-treated and in 53% of placebo-treated children. Our follow-up results indicate that the beneficial effect of prenatal glucocorticoid treatment on cerebral complications (intraventricular haemorrhage or periventricular leucomalacia) demonstrated during the neonatal period may be followed by a lower incidence of cerebral palsy in surviving premature children.

The contribution of risk factors to the effect of early otitis media with effusion on later language, reading, and spelling

A cohort of 946 children who were screened for otitis media with effusion (OME) from the ages of 2 to 4 were studied for language, reading, and spelling at 7 years of age. The effects of OME in combination with single risk factors and with increasing numbers of risk factors were investigated. An interaction with an additional risk factor was found only for gender and OME, with boys' spelling influenced negatively by a history of OME. OME in combination with preterm birth and low birthweight also appears to put children at risk for later language and educational problems. Although a negative linear relation between the number of risk factors and later functioning was found, it is suggested that OME, even when combined with a number of other risk factors, produces only minor effects on later language, reading, and spelling.

Neuropsychological consequences of very low birth weight and asphyxia at term: follow-up until school-age

This prospective, longitudinal study examined neuropsychological consequences of different conditions associated with risks of perinatal asphyxia. Four groups of children, 5 to 9 years of age, were studied: (1) very low birth weight (VLBW) children born small for gestational age (SGA) (n = 34); (2) VLBW children born appropriate for gestational age (AGA) (n = 43); (3) children with signs of birth asphyxia at term (birth asphyxia) (n = 36), and (4) control children (n = 45). Moderately and severely disabled children were excluded. The WISC-R and the NEPSY, a new neuropsychological assessment consisting of attention, language, motor, sensory, visuospatial, and memory subtests, were administered. The VLBW-SGA group had the poorest test results. The VLBW-AGA group was somewhat less impaired, whereas the birth asphyxia group performed at the control group level. Impairment, when present, tended to be diffuse in all groups, affecting psychometric intelligence, naming, visuo-motor performance, tactile finger discrimination, attention, and phonological analysis.

Prediction of lower developmental performances of healthy neonates by neonatal EEG-sleep measures

Previous neurophysiologic studies from our laboratory have demonstrated altered EEG-sleep behavior at conceptional term ages in healthy preterm infant compared with a term cohort. Developmental assessments at 12 and 24 months of age of 16 children in each cohort were compared using MANOVA. Differences were detected on MANOVA between each cohort on Bayley mental and motor performance scores, while social skills (Vineland) and temperament (Carey) were similar. Healthy preterm infants had lower scores at 12 months of age (P < .0001) and 24 months (P < .04) than term infants before adjustment for prematurity. No group differences were observed after adjustment. For the combined cohort of 32 healthy neonates, specific neonatal EEG-sleep measures were included as predictor variables in regression analyses with Bayley mental scores as outcome variables. Lower Bayley mental scores at 12 and 24 months were associated with higher spectral EEG correlations, lower spectral EEG energies in the beta frequency ranges, fewer arousals per minute, lower rapid eye movements per minute, and shorter sleep latencies from awake state to active sleep. Significant associations were observed before adjustment for prematurity at both 12 and 24 months, and after adjustment at 12 months of age for lower spectral beta EEG energies. Lower socioeconomic class also correlated with lower developmental scores. Even in the absence of major neonatal illnesses, brain adaptation to prematurity influences later developmental outcome. Adjustment for "age equivalency" may be required up to at least 24 months of age even in a healthy preterm population.

Development of a regional cohort of very-low-birthweight children at six years: cognitive abilities are associated with neurological disability and social background

The authors studied the intelligence, memory, visuomotor skills and la nguage of 298 six-year-old children with very low birthweight (VLBW) (less that 1500g). Of 591 VLBW childern born July 1983 to June 1986 within 50km of the centre of Hamburg, Germany, 330 were traceable at age six years and 298 of these were seen by a neuropaediatrician and a psychologist; the other 19 were too severely disabled for psychological assessment with the standardized tests used. The mean memory performance of VLBW children at age six years was below the standard mean in all diagnostic and socio-economic subgroups. As expected, visuomotor development was clearly influenced by neurological but not socio-economic status. Intelligence and language skills were much more closely related to socio-economic background that to neurological morbidity. However, VLBW children with hyperactivity, clumsiness or cerebral palsy differed significantly in intelligence and visuomotor performance from those without neurological symptoms.

Hearing loss at the age of 5 years of children born preterm--a matter of definition

The effect of three common hearing impairment criteria on the prevalence of hearing loss was evaluated in 58 prospectively followed-up 5-year-old children born preterm at < or = 32 weeks of gestation. Audiological assessment was done as part of an extensive neurodevelopmental evaluation at the age of 5 years. With the criterion based on the classification of the World Health Organization (average threshold hearing level > 25 dB at frequencies of 0.5, 1 and 2 kHz, classified according to the less impaired side) there were two preterm children with mild hearing impairment. With Clark's criterion (unilateral average threshold hearing level > 15 dB at frequencies of 0.5, 1 and 2 kHz) eight children had slight hearing impairment; seven of these had conductive hearing problems. With the criterion of a single frequency-specific deficit > 15 dB for 0.25-4 kHz the number of hearing-impaired children was 28 out of 54 (51.9%), most of whom had conductive or unspecified hearing deficits. Moreover, of the four multiply handicapped, retarded children whose pure tone thresholds were not assessed monaurally, three would belong to the hearing-impaired group according to Clark's criterion and four according to the frequency-specific criterion.

Parents' estimation of psychomotor development in very low birthweight (VLBW) infants

BACKGROUND

Within a longitudinal developmental surveillance project we tested the accuracy of the Revised Prescreening Developmental Questionnaire (R-PDQ) to detect developmental retardation in very low birthweight (VLBW) infants.

METHODS

Seventy surviving VLBW-infants born between July 1992 and December 1993 were re-examined at 6 months corrected age. The parent-completed questionnaires (n = 67) were compared with developmental assessment using the Griffiths Developmental Scale.

RESULTS

At 6 months corrected age, normal results of the Griffiths Developmental Scale (developmental quotient > or = 81) were found in 61/67 (91%) VLBW-infants and in 45/67 (67%) questionnaires (no or one 'delay'). The parents identified all six infants with psychomotor retardation on the Griffiths Developmental Scale (co-positivity 100%). However, only 45/61 infants with normal development were so identified with the R-PDQ (co-negativity 74%, positive predictive value 27%).

CONCLUSIONS

The R-PDQ discovered all infants whose developmental quotient was two standard deviations below the mean on the Griffiths Developmental Scale. The relatively high proportion of false positive R-PDQ results corresponded to lower developmental quotients within the normal range. Therefore, the R-PDQ provides a useful screening instrument for VLBW-infants.