Jorrit F. de Kieviet

Brain development of very preterm and very low‐birthweight children in childhood and adolescence: a meta‐analysis

Aim  The aim of this article was to clarify the impact and consequences of very preterm birth (born <32wks of gestation) and/or very low birthweight ([VLBW], weighing <1500g) on brain volume development throughout childhood and adolescence.

Attention Problems of Very Preterm Children Compared with Age-Matched Term Controls at School-Age

OBJECTIVES To clarify the severity, specificity, and neurocognitive underpinnings of attention problems in very preterm children. STUDY DESIGN A sample of 66 preterm (<32 weeks gestation), mean (SD) age 7.5 (0.4) years, and 66 age-matched term controls participated. Symptoms of inattention were assessed using parent and teacher-rated questionnaires, and neurocognitive measures included speed and consistency in speed of information processing, lapses of attention (tau), alerting, orienting, and executive attention, as well as verbal and visuospatial working memory. Group differences were investigated using ANOVA, and Sobel tests were used to clarify the mediating role of neurocognitive impairments on attention problems. RESULTS There was a large decrease in visuospatial working memory abilities (P < .001, d = .87), and medium increases in tau (P = .002, d = 0.55) as well as parent and teacher ratings of inattention (range d = 0.40-0.56) in very preterm children compared with term peers. Tau and visuospatial working memory were significant predictors of parent (R(2) = .161, P < .001 and R(2) = .071, P = .001; respectively) and teacher (R(2) = .152, P < .001 and R(2) = .064, P = .002; respectively) ratings of inattention, and completely explained the effects of very preterm birth on attention problems. CONCLUSIONS Increased lapses of attention and poorer visuospatial working memory fully account for the attention problems in very premature children at school-age.

Perinatal Infections and Neurodevelopmental Outcome in Very Preterm and Very Low-Birth-Weight Infants: A Meta-Analysis

IMPORTANCE Perinatal infections are commonly present in preterm and very low-birth-weight (VLWB) infants and might contribute to adverse neurodevelopmental outcome. OBJECTIVE To summarize studies evaluating the effect of perinatal infections on neurodevelopmental outcome in very preterm/VLBW infants. EVIDENCE REVIEW On December 12, 2011, we searched Medline, PsycINFO, Embase, and Web of Knowledge for studies on infections and neurodevelopmental outcome. All titles and abstracts were assessed for eligibility by 2 independent reviewers. We also screened the reference lists of identified articles to search for additional eligible studies. Preselected criteria justified inclusion in this meta-analysis: (1) the study included infants born very preterm (≤32 weeks) and/or with VLBW (≤1500 g); (2) the study compared infants with and without perinatal infection; (3) there was follow-up using the Bayley Scales of Infant Development 2nd edition; and (4) results were published in an English-language peer-reviewed journal. The quality of each included study was assessed using the Newcastle-Ottawa Scale. FINDINGS This meta-analysis includes 18 studies encompassing data on 13.755 very preterm/VLBW infants. Very preterm/VLBW infants with perinatal infections had poorer mental (d = -0.25; P < .001) and motor (d = -0.37; P < .001) development compared with very preterm/VLBW infants without infections. Mental development was most impaired by necrotizing enterocolitis (d = -0.40; P < .001) and meningitis (d = -0.37; P < .001). Motor development was most impaired by necrotizing enterocolitis (d = -0.66; P < .001). Chorioamnionitis did not affect mental (d = -0.05; P = .37) or motor (d = 0.19; P = .08) development. CONCLUSIONS AND RELEVANCE Postnatal infections have detrimental effects on mental and motor development in very preterm/VLBW infants.

Placental pathology and long-term neurodevelopment of very preterm infants

OBJECTIVE The objective of the study was to compare neonatal morbidity and long-term neurodevelopmental outcome between very preterm infants with placental underperfusion and very preterm infants with histological chorioamnionitis. STUDY DESIGN We measured the mental and motor development at age 2 and 7 years in 51 very preterm infants with placental underperfusion and 21 very preterm infants with histological chorioamnionitis. RESULTS At 2 years, very preterm infants with placental underperfusion had poorer mental development than very preterm infants with histological chorioamnionitis (mean [SD] 90.8 [18.3] vs 104.1 [17.2], adjusted d = 1.12, P = .001). Motor development was not different between both groups (92.8 [17.2] vs 96.8 [8.7], adjusted d = 0.52, P = .12). At 7 years, large, although nonsignificant, effects were found for better mental and motor development and fewer behavioral problems in infants with histological chorioamnionitis. CONCLUSION Placental pathology contributes to variance in mental development at 2 years and should be taken into account when evaluating neurodevelopmental outcome of very preterm infants.

A crucial role of altered fractional anisotropy in motor problems of very preterm children.

BACKGROUND Very preterm children (<32 weeks of gestation) are characterized by impaired white matter development as measured by fractional anisotropy (FA). This study investigates whether altered FA values underpin the widespread motor impairments and higher incidence of developmental coordination disorder (DCD) in very preterm children at school-age. METHODS Thirty very preterm born children (mean (SD) age of 8.6 (0.3) years) and 47 term born controls (mean [SD] age 8.7 [0.5] years) participated. Motor development was measured using the Movement Assessment Battery for Children. A score below the 15th percentile was used as a research diagnosis of DCD. FA values, as measure of white matter abnormalities, were determined for 18 major white matter tracts, obtained using probabilistic diffusion tensor tractography. RESULTS Large-sized reductions in FA of the cingulum hippocampal tract right (d = 0.75, p = .003) and left (d = 0.76, p = .001), corticospinal tract right (d = 0.56, p = .02) and left (d = 0.65, p = .009), forceps major (d = 1.04, p < .001) and minor (d = 0.54, p = .02) were present in very preterms, in particular with a research diagnosis of DCD. Reduced FA values moderately to strongly related to motor impairments. A ROC curve for average FA, as calculated from tracts that significantly discriminated between very preterm children with and without a research diagnosis of DCD, showed an area under curve of 0.87 (95% CI 0.74-1.00, p = .001). CONCLUSIONS This study provides clear evidence that reduced FA values are strongly underpinning motor impairment and DCD in very preterm children at school-age. In addition, outcomes demonstrate that altered white matter FA values can potentially be used to discriminate between very preterm children at risk for motor impairments, although future studies are warranted.

Lower limb muscle strength (LLMS): Why sedentary life should never start? A review

Aging coincides with a decline in LLMS. Preserving LLMS may be considered a very important determinant of functional independence in the elderly. To maintain LLMS the question arises whether habitual physical activities (HPA) can prevent a decline in LLMS. This review aims to determine the relationship between HPA throughout life and LLMS above age 50. Using relevant databases and keywords, 70 studies that met the inclusion criteria were reviewed and where possible, a meta-analysis was performed. The main findings are: (1) the present level of HPA is positively related to LLMS; (2) HPA in the past has little effect on present LLMS; (3) HPA involving endurance have less influence on LLMS compared to HPA involving strength; (4) people with a stable habitually physically active life are able to delay a decline in LLMS. In conclusion, to obtain a high amount of LLMS during aging, it is important to achieve and maintain a high level of HPA with mainly muscle-strengthening activities.

A crucial role for white matter alterations in interference control problems of very preterm children

Background:Attention problems are among the most prominent behavioral deficits reported in very preterm children (below 32 wk of gestation) at school age. In this study, we aimed to elucidate the brain abnormalities underlying attention problems in very preterm children by investigating the role of abnormalities in white and gray brain matter during interference control, using functional magnetic resonance imaging (fMRI)–guided probabilistic diffusion tensor tractography.Methods:Twenty-nine very preterm children (mean (SD) age: 8.6 (0.3) y), and 47 term controls (mean (SD) age: 8.7 (0.5) y), performed a fMRI version of the Eriksen Flanker task measuring interference control.Results:Very preterm children showed slower reaction times than term controls when interfering stimuli were presented, indicating poorer interference control. Very preterm children and term controls did not differ in mean activation of the cortical regions involved in interference control. However, impaired fractional anisotropy (FA) was found in very preterm children in specifically those fiber tracts that innervate the cortical regions involved in interference control. Lower FA was related to poorer interference control in very preterm children.Conclusion:White matter alterations have a crucial role in the interference control problems of very preterm children at school age.

Academic performance of children born preterm: a meta-analysis and meta-regression

Background Advances in neonatal healthcare have resulted in decreased mortality after preterm birth but have not led to parallel decreases in morbidity. Academic performance provides insight in the outcomes and specific difficulties and needs of preterm children. Objective To study academic performance in preterm children born in the antenatal steroids and surfactant era and possible moderating effects of perinatal and demographic factors. Design PubMed, Web of Science and PsycINFO were searched for peer-reviewed articles. Cohort studies with a full-term control group reporting standardised academic performance scores of preterm children (<37 weeks of gestation) at age 5 years or older and born in the antenatal steroids and surfactant era were included. Academic test scores and special educational needs of preterm and full-term children were analysed using random effects meta-analysis. Random effects meta-regressions were performed to explore the predictive role of perinatal and demographic factors for between-study variance in effect sizes. Results The 17 eligible studies included 2390 preterm children and 1549 controls. Preterm children scored 0.71 SD below full-term peers on arithmetic (p<0.001), 0.44 and 0.52 SD lower on reading and spelling (p<0.001) and were 2.85 times more likely to receive special educational assistance (95% CI 2.12 to 3.84, p<0.001). Bronchopulmonarydysplasia explained 44% of the variance in academic performance (p=0.006). Conclusion Preterm children born in the antenatal steroids and surfactant era show considerable academic difficulties. Preterm children with bronchopulmonarydysplasia are at particular risk for poor academic outcome.

Visual search and attention in five-year-old very preterm/very low birth weight children

INTRODUCTION This study aimed to establish visual search performance and attention functioning in very preterm/very low birth weight (VP/VLBW) children using novel and well established measures, and to study their contribution to intellectual functioning. METHODS Visual search and attention network efficiency were assessed in 108 VP/VLBW children and 72 age matched term controls at 5.5 years corrected age. Visual search performance was investigated with a newly developed paradigm manipulating stimulus density and stimulus organization. Attention functioning was studied using the Attention Network Test (ANT). Intellectual functioning was measured by a short form of the Wechsler Preschool and Primary Scale of Intelligence. Data were analyzed using ANOVAs and multiple regression analyses. RESULTS Visual search was less efficient in VP/VLBW children as compared to term controls, as indicated by increased search time (0.31 SD, p = .04) and increased error rate (0.36 SD, p = .02). In addition, VP/VLBW children demonstrated poorer executive attention as indicated by lower accuracy for the executive attention measure of the ANT (0.61 SD, p < .001). No differences were found for the alerting (0.06 SD, p = .68) and orienting attention measures (0.13 SD, p = .42). Visual search time and error rate, and executive attention, collectively, accounted for 14% explained variance in full scale IQ (R(2) = .14, p < .001). DISCUSSION VP/VLBW children were characterized by less efficient visual search ability and reduced executive attention. Visual attention dysfunctions contributed to intelligence, suggesting the opportunity to improve intellectual functioning by using interventions programs that may enhance attention capacities.

The crucial role of the predictability of motor response in visuomotor deficits in very preterm children at school age

We aimed to clarify the underpinnings of widespread visuomotor deficits in very preterm children.