Influence of Additional Ankle Weights on Kinematic Variables of Late Preterm Infants Aged 3–4 Months

The authors analyzed and compared the effect of additional weight on the spatiotemporal parameters of the kicking movement of late preterm and full-term infants. The experiment was divided into 4 conditions: training, baseline, weight, and postweight. In the W condition, a weight of one third the lower limb mass was added to the infant's ankle. During the baseline and postweight conditions, the ankle weight was removed. Late preterm infants do not differ from full-term infants in relation to spatiotemporal variables at 3 and 4 months. However, during the weight condition, the straightness index and the hip-ankle and knee-ankle correlations decreased in the preterm infants at both ages. In contrast, the straightness index increased in the postweight condition compared to the baseline values at both ages.     

The contribution of visual processing to academic achievement in adolescents born extremely preterm or extremely low birth weight

Children born extremely preterm (EP, <28 weeks) and/or extremely low birth weight (ELBW, <1000 g) have more academic deficiencies than their term-born peers, which may be due to problems with visual processing. The aim of this study is to determine (1) if visual processing is related to poor academic outcomes in EP/ELBW adolescents, and (2) how much of the variance in academic achievement in EP/ELBW adolescents is explained by visual processing ability after controlling for perinatal risk factors and other known contributors to academic performance, particularly attention and working memory. A geographically determined cohort of 228 surviving EP/ELBW adolescents (mean age 17 years) was studied. The relationships between measures of visual processing (visual acuity, binocular stereopsis, eye convergence, and visual perception) and academic achievement were explored within the EP/ELBW group. Analyses were repeated controlling for perinatal and social risk, and measures of attention and working memory. It was found that visual acuity, convergence and visual perception are related to scores for academic achievement on univariable regression analyses. After controlling for potential confounds (perinatal and social risk, working memory and attention), visual acuity, convergence and visual perception remained associated with reading and math computation, but only convergence and visual perception are related to spelling. The additional variance explained by visual processing is up to 6.6% for reading, 2.7% for spelling, and 2.2% for math computation. None of the visual processing variables or visual motor integration are associated with handwriting on multivariable analysis. Working memory is generally a stronger predictor of reading, spelling, and math computation than visual processing. It was concluded that visual processing difficulties are significantly related to academic outcomes in EP/ELBW adolescents; therefore, specific attention should be paid to academic remediation strategies incorporating the management of working memory and visual processing in EP/ELBW children.     

Prereading skills of very-low-birth-weight prematurely born Finnish children

Our objective was to study the prereading skills of very-low-birth-weight (VLBW; ≤ 1500 g) prematurely born children at the age of five years. A regional cohort of 89 VLBW children and 152 full-term (FT) born children was assessed for letter knowledge, phonological processing, and speeded naming. Full-scale IQ (FSIQ) was assessed using a short version of WPPSI-R. The associations of parental and neonatal factors, and FSIQ with prereading skills were assessed. VLBW group had poorer prereading skills, and there were more VLBW children at-risk (performing < ?1 SD) compared to FT children in phonological processing (23% vs. 9%, p = .002), letter knowledge (27% vs. 14%, p = .017), and the accuracy of speeded naming (26% vs. 13%, p = .020). VLBW children had lower average FSIQ and Performance IQ (both comparisons p < .001) than FT controls, but Verbal IQ did not differ. When FSIQ was used as a covariate, VLBW children did not differ from the FT group in prereading skills indicating that they are at risk for more global developmental problems. Lower parental level of education as well as parent's reading problems were negatively associated with VLBW children's prereading skills. Positively, about 75% of VLBW children performed within the normal range in each individual prereading skill.     

A comparative analysis of the validity of several approaches to the scoring of the behavior of the preterm infant

A group of very low birthweight preterm infants (mean WEIGHT = 1193.6 g; mean gestational AGE = 31.1 weeks) were examined with the PREMIE. The PREMIE is a modification of the scoring system of the full term Brazelton Neonatal Behavioral Assessment (BNBAS) examination for use with preterm infants. Infants were assessed during the acute phase of cardio-respiratory illness (mean AGE = 7 days) and during the recovery phase (mean AGE = 22 days). Many modifications in procedure were required. Several analyses were performed to assess the redundancy and the comparative validity of the scoring systems of the PREMIE, the BNBAS, and the BNBAS + (the BNBAS plus a set of five additional preterm items). Results indicated that the three scoring systems were highly redundant, that they were equally related to physiologic and clinical variables, and that they were similar in their sensitivity to behavioral change and stability. Overall the results offered little in the way of differentiating among these three scoring systems with this group of infants, raising doubts about the need to use the PREMIE or other scoring systems like it for many research purposes.     

The effect of mother-infant skin-to-skin contact on plasma cortisol and β-endorphin concentrations in preterm newborns

The aim of this study was to assess the effect of mother-infant skin-to-skin contact on plasma β- endorphin and cortisol concentrations in stable, preterm infants on a newborn intensive care unit. Blood samples were obtained before and at the end of a 20-min period of skin-to-skin contact. Similarly paired samples, obtained at the same times and after the same interval, without skin-to- skin contact, were obtained on another day and served as controls. Both cortisol and β-endorphin concentrations fell significantly after the skin-to-skin session (cortisol: geometric mean change 66%, p=0.008; β-endorphin: geometric mean change 74%, p=0.002). There was also a significant fall in cortisol levels during the control session (geometric mean change 78%, p=0.02), in contrast to β-endorphin levels, in which there was no significant change. Analysis of variance showed that the fall in β-endorphin, but not the fall in cortisol, during the skin-to-skin session was significant when compared with the control session. These results emphasize the hormonal responsiveness of the preterm newborn to relatively minor interventions. We conclude that maternal skin-to-skin contact results in a significant reduction in circulating β-endorphin in the newborn; there was no evidence of any adverse effect.     

Poorer divided attention in children born very preterm can be explained by difficulty with each component task,not the executive requirement to dual-task

Children born very preterm (VP, ≤ 32 weeks) exhibit poor performance on tasks of executive functioning. However, it is largely unknown whether this reflects the cumulative impact of non-executive deficits or a separable impairment in executive-level abilities. A dual-task paradigm was used in the current study to differentiate the executive processes involved in performing two simple attention tasks simultaneously. The executive-level contribution to performance was indexed by the within-subject cost incurred to single-task performance under dual-task conditions, termed dual-task cost. The participants included 77 VP children (mean age: 7.17 years) and 74 peer controls (mean age: 7.16 years) who completed Sky Search (selective attention), Score (sustained attention) and Sky Search DT (divided attention) from the Test of Everyday Attention for Children. The divided-attention task requires the simultaneous performance of the selective- and sustained-attention tasks. The VP group exhibited poorer performance on the selective- and divided-attention tasks, and showed a strong trend toward poorer performance on the sustained-attention task. However, there were no significant group differences in dual-task cost. These results suggest a cumulative impact of vulnerable lower-level cognitive processes on dual-tasking or divided attention in VP children, and fail to support the hypothesis that VP children show a separable impairment in executive-level abilities.     

Social determinants of health,prenatal maternal stress,and earlier birth during the COVID-19 pandemic

During the COVID-19 pandemic, pregnant women, especially those from socioeconomically disadvantaged and marginalized groups, experienced unprecedented stress. Prenatal stress and social determinants of health (SDoH) such as lower education and lack of a relationship partner are known to contribute to earlier birth. However, whether SDoH and stress independently contribute or whether the harmful impact of SDoH is mediated by stress is unknown. Moreover, the contributions of these factors has not been investigated in the context of a communal health crisis such as the COVID-19 pandemic. To examine these processes, we used a longitudinal cohort of 2473 women pregnant during the COVID-19 pandemic who reported a live birth. We compared structural equation models predicting gestational age at birth from SDoH (race/ethnicity, education, financial security, health insurance, relationship status, and lifetime abuse) and from prenatal maternal stress related and unrelated to the COVID-19 pandemic. Results indicate that the association of SDoH with earlier birth was partially mediated by prenatal stress. These findings help uncover mechanisms explaining health disparities in the U.S. and highlight the need to address both SDoH and the stress that these factors produce in under-resourced and marginalized communities.